Influence of Sonication and Graphene Nanoplatelets Concentration on Rheological and Filtration Properties of Water-based Mud

Influence of Sonication and Graphene Nanoplatelets Concentration on Rheological and Filtration Properties of Water-based Mud | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Influence of Sonication and Graphene Nanoplatelets Concentration on Rheological and Filtration Properties of Water-based Mud Kai Chen Wong, Sathiasegkaran Muthumanickam, Veeradasan Perumal, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7692464/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The rising complexity of drilling under high-pressure and high-temperature (HPHT) conditions creates substantial challenges in fluid loss control, thermal stability, and rheological performance for drilling fluids. Nanoparticles, particularly graphene, have garnered tremendous attention as a promising additive to improve the performance of drilling fluids. This study investigates graphene nanoplatelets (GNPs) as a potential novel application to enhance the rheological performance and fluid loss control of WBMs. A comparative analysis of the impact of rheological performance, low-pressure, and low-temperature (LPLT) filtration test, high-pressure, and high-temperature (HPHT) filtration test is presented on WBMs with as-received and sonicated GNPs before tested with varying GNPs concentrations, ranging from 0.1 ppb to 0.5 ppb, under a 9 ppg mud weight. The samples were hot rolled at 250°F and 100psi for 16 hours to evaluate the influence of thermal aging on the properties of the GNPs water-based muds (WBMs). The experimental findings reveal that the mud with sonicated GNPs exhibits better performance, with 9.09% and 26.39% greater reductions in HPHT fluid loss and filter cake thickness, respectively. Besides, optimum concentration of 0.4ppb of GNPs results in a lower filtrate volume in HPHT conditions by 16.36%, and mud cake thickness in both LPLT and HPHT conditions by 17.08% and 21.44% respectively. The yield point has increased by 36.36%, while the plastic viscosity remains unchanged. Overall, this research demonstrates the capabilities of GNPs, particularly when sonicated, in enhancing the performance of WBMs, even at low concentrations, especially under HPHT conditions. Graphene nanoplatelets high-pressure high-temperature sonication water-based muds thermal aging fluid loss Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 1.0 Introduction Drilling fluid is defined as a composite fluid that facilitates the formulation and abstraction of cuttings from a drilling borehole. It serves as a lubricant for the drilling bits, maintaining the subsurface pressure, reducing friction between the drilling string and the wellbore side, and carrying the cuttings from beneath the bit, transporting them up to the annulus [ 1 ], [ 2 ]. Over the past few decades, research on drilling fluid formulations has continued to evolve to address the fluid loss control and rheology optimization associated with high-pressure, high-temperature (HPHT) drilling environments [ 3 ], [ 4 ], [ 5 ]. With the declining oil and gas reserves in onshore and shallow offshore regions, coupled with the rising demand for natural gas and crude oil worldwide, deeper well drilling, especially under HPHT conditions, has become increasingly vital. Currently, three drilling fluids are widely considered for the wellbore drilling process, namely Oil-based Mud (OBM), Water-based Mud (WBM), and Synthetic-based Mud (SBM). While water-based muds (WBMs) are more cost-effective [ 6 ] and environmentally friendly than oil-based alternatives, they often underperform in extreme conditions due to shale swelling [ 7 ], [ 8 ]. Shale swelling elevates the equivalent circulation density (ECD), which may lead to a significant operational challenge, such as stuck pipe, reduction of hole cleaning efficiency, and the possible collapse of the wellbore when the level surpasses the formation’s fracture gradient [ 9 ], [ 10 ], [ 11 ]. In earlier days, polymeric additives such as polyanionic cellulose (PAC), carboxymethyl cellulose (CMC), and xanthan gum (XC) were commonly used to enhance the performance of WBMs. However, they demonstrated limited thermal stability [ 4 ], [ 12 ], and poor rheological and filtration properties under harsh condition [ 13 ]. Moreover, fine calcium carbonate asphalt that is used conventionally as a plugging agent is of a micron scale, which limits its effectiveness in forming a compact and impermeable filter membrane in preventing excessive filtrate loss [ 7 ]. A detailed comparison is provided in Table S1 . Based on these notions, several studies have investigated the potential of nanomaterials as promising additives[ 14 ], [ 15 ], [ 16 ], [ 17 ] with GNPs standing out due to their excellent thermal stability up to 650°C, high specific surface area, and mechanical strength [ 16 ]. Research indicates that GNPs can improve plastic viscosity (PV), yield point (YP), and reduce both mud cake thickness and fluid loss [ 18 ], [ 19 ]. Graphene is a single layer of two-dimensional (2D) carbon atoms arranged in a tightly packed hexagonal honeycomb lattice [ 20 ]. Due to its unique structure, the 2D lattice structure of graphene can be wrapped up into fullerene (zero-dimensional, 0D), rolled up into a carbon nanotube (one-dimensional, 1D), or stacked to form graphite [ 21 ]. Graphene itself appears in black, fine, shiny powder. It is hydrophobic and chemically inert. There are several types of graphene due to the variations in the number of layers, lateral dimension, and surface chemistry of graphene materials. These include graphene nanoplatelets (GNP), graphene oxide (GO), few layers of graphene, etc [ 21 ]. While preparing the graphene, mechanical exfoliation via ultrasonic sonication is widely used in drilling fluid studies because it is cost-effective and simple, despite the struggles for large-scale production [ 22 ], [ 23 ]. While several studies have reported the parameters employed in the sonication preparation of GNPs and other graphene-based materials [ 23 ], [ 24 ], [ 25 ], [ 26 ], the methodologies, including time, power, and temperature vary considerably, and it is not clearly reported. In particular, although sonication is frequently applied as a dispersion technique, there has been no systematic investigation comparing the performance of sonicated versus as-received GNPs in drilling fluid formulations. This gap raises uncertainty regarding the necessity of sonication and its actual impact on drilling fluid performance. On the contrary, some studies provide only qualitative descriptions of GNP preparation, such as manual stirring to ensure apparent homogeneity, without systematic consideration of key parameters. Certain cases of research even only apply stirring with a high-speed mixer for as little as 15 minutes to confirm the homogeneous dispersion of graphene [ 14 ], [ 27 ]. Table S2 shows the summary of graphene sonication parameters and observation details from a few studies. In addition, a study conducted by Zhang on the dispersion effect of GNPs found that temperature control contributes to the exfoliation degree of the GNPs [ 28 ]. Temperatures higher than 35℃ will reduce the degree of exfoliation, but none of this was mentioned in the studies of graphene-added materials used for drilling fluids. This study aims to provide a new insight into investigating the performance of as-received and sonicated GNPs on rheological and filtration properties of WBMs. GNPs are first characterised by SEM-EDX analysis. Besides, independent variables including sonication power, temperature, duration, and GNPs concentration are well-optimised to produce quality sonicated GNPs. The latter that exhibits a better performance is further analysed across varying concentrations from 0.1g to 0.5g to assess the influence of GNPs concentration on the rheological and filtration properties. Overall, the structure of the study takes the form of four chapters, including introduction, methodology, results and discussion, as well as conclusion. 2.0 Methodology 2.1 Materials Graphene nanoplatelets (GNPs) with CAS Number 7782-42-5 were procured from Nanografi. They appeared as a fine black powder with an average diameter of 30µm, 5nm size, and an average surface area of 170 \(\:{m}^{2}\) /g. Table S3 shows the function of the mud additives for the drilling mud. Drill water was used as a base fluid to dissolve other mud additives for the preparation of drilling mud. API bentonite was added to provide wellbore stability, while potassium chloride served as a shale inhibitor and provided salinity, and sodium hydroxide functioned to increase the alkalinity of the drilling mud. Xanthan gum functioned as the primary viscosifier and high-purity polyanionic cellulose (PAC-HP) as the secondary viscosifier. Fluid loss control agents included low-viscosity polyanionic cellulose (hydro-PAC-LV), high-purity polyanionic cellulose (PAC-HP), modified starch (OPTA-STAR), and GNPs. Calcium carbonate was incorporated as a bridging agent, and barite was used as a weighing agent, contributing to the desired mud density of the drilling fluids. 2.2 Equipment All the mud additives were weighed using an electronic balance before it is mixed to ensure uniform distribution. The mixing process was carried out using a Fann Five Spindle Multimixer Model 9B. Sonication of the GNPs was performed using an Xiang Yi Ultrasonic Homogeniser. Rheological properties of the WBMs were then determined by using a Fann 35SA Viscometer following mud density measurement using a FANN Mud Balance Model 140. In addition, the filtration properties of the WBMs were evaluated using the TEMCO LPLT Filter Press and OFITE HPHT Filter Press. The entire procedure was repeated after hot rolling of mud using the Fann Roller Oven. 2.3 GNPs Preparation The preparation method for GNPs is done by mechanical exfoliation through sonication, referencing a few research papers. GNPs with a weight ranging from 0.1g to 0.5g were sonicated in 100 mL of water for 1 hour. 100 ml of water is treated with 0.1g of surfactants (sodium carboxymethyl cellulose) to ensure a better dispersion of GNPs [ 29 ]. Prior to sonication, magnetic stirrer was used to stir and dissolve the surfactants for about 15 minutes. Sonication was performed using a pulsed mode of 10 seconds on and 10 seconds off, with a power output of 400W and a probe frequency of around 22kHz. The temperature of the solution is controlled below 35℃ to ensure better deflocculation efficiency. 2.4 Mud Preparation The drilling muds were prepared according to the procedures outlined in Table S4 and Table S5. Initially, 230ml of drill water was placed into the multimixer cup, followed by the addition of 0.2g of soda ash and 5g of API bentonite. Next, 0.2g of sodium hydroxide and 12g of potassium chloride were added to the formulation. 1.5g of hydro-PAC-LV and 1g of PAC-HP were then added to the mud before adding 0.8g of xanthan gum, 0.25g of CMC-LV, and 1g of OPTASTAR. Each of the additives added above was mixed for 5 minutes before another additives were added. After that, 10g of calcium carbonate was added and mixed for 15 minutes, followed by 17g of barite, which was mixed for 25 minutes. The procedure above was repeated to prepare mud containing different concentrations of GNPs, varying from 0.1g to 0.5g. 2.5 Rheological Testing Rheology tests were conducted in accordance with API RP 13B-1 [ 30 ] using a Fann 35A Viscometer, where dial readings at \(\:{\theta\:}_{600}\) , \(\:{\theta\:}_{300}\) , \(\:{\theta\:}_{200}\) , \(\:{\theta\:}_{100}\) , \(\:{\theta\:}_{6}\) , and \(\:{\theta\:}_{3}\) were recorded for analysis. The readings of 10s gel strength and 10 min gel strength were taken at \(\:{\theta\:}_{3}\) rpm after the formulated drilling muds were allowed to rest for 10 seconds and 10 minutes. Plastic viscosity (PV), and yield point (YP) can then be calculated using the following formula: $$\:PV=\:{\theta\:}_{600}-\:{\theta\:}_{300}$$ $$\:YP=\:{\theta\:}_{300}-PV$$ 2.6 Filtration Testing Filtration characteristics of the drilling mud were evaluated in accordance with API RP 13B-1 [ 30 ] using the TEMCO LPLT Filter Press Cell and the OFITE HPHT Filter Press Cell. For the LPLT tests, a filter paper with an effective area of 7.1 \(\:{\text{i}\text{n}}^{2}\) was employed, while the HPHT tests utilized a filter paper with an effective area of 3.5 \(\:{\text{i}\text{n}}^{2}\) . The LPLT filtration tests were conducted at ambient temperature under a pressure of 100 psi, while the HPHT filtration tests were conducted at a 500 psi differential pressure and a temperature of 250°F. The selected HPHT conditions served as a preliminary screen to quantify the baseline impact of GNPs on filtration properties before subsequent evaluation at ultra HPHT conditions. After 30 minutes of testing, the volume of filtrate loss was recorded. Subsequently, the filter cake was carefully retrieved, and its average thickness was measured using a digital vernier calliper. 2.7 GNPs Characterisation Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Analysis (EDX) was used for the analysis of the GNPs. By directing a finely focused beam of high-energy electrons onto the surface of the specimen and capturing the signals from secondary electrons and backscattered electrons, SEM can generate high-resolution images up to the magnification of 5.00 kx. Besides, EDX analysis provides an elemental analysis and chemical characterisation of the sample. 3.0 Results and Discussion 3.1 Characterisation of GNPs Figure S1 illustrates the images from scanning electron microscopy (SEM) and Energy Dispersive X-ray Analysis (EDX). Figure S1 (a) of SEM micrographs revealed that the GNPs exhibit a broad size distribution with agglomerated morphologies. Further detailed picture in Figure S1 (b) shows stacked multilayer GNP sheets with overlapping regions, further confirming the occurrence of agglomeration. The stacked and agglomerated structure of GNPs suggests a reduced surface interaction with the surrounding medium, which may influence its dispersibility. Nevertheless, sharp edges and smooth surfaces observed in the SEM images highlight the distinctive features of GNPs [ 27 ] The latter characteristics is particularly beneficial in drilling applications, as smooth graphene planes can reduce the friction between the drill pipe and the wellbore, thereby lowering the torque and drag [ 31 ]. Additionally, the EDX analysis in Figure S1 (c) confirmed the high purity of the GNPs, with carbon and oxygen contents measured at 82.12 wt.% and 17.88 wt.%, respectively. This composition suggests minimal contamination from metallic catalysts or other residues, thereby ensuing the chemical stability under downhole conditions. Overall, the morphological features of GNPs observed are expected to play a crucial role in improving fluid loss control and rheological optimization of WBMs. 3.2 Performance of as-received GNPs and Sonicated GNPs with the same Concentration Rheological Properties The rheological properties of mud with sonicated and as-received GNPs were tested under two conditions: before hot rolling (BHR) and after hot rolling (AHR). The rheological readings were measured following hot rolling at 250°F and 150 psi for 16h. Hot rolling simulates the mud performance under elevated temperature and pressure of the borehole. During dynamic rolling, WBMs are constantly circulating to simulate the shear stress experienced by the drilling fluids when circulating the wellbore. It provides a more realistic representation of downhole conditions compared with static hot rolling. Therefore, the AHR value is commonly given more emphasis compared to the BHR value as it simulates more accurate downhole conditions and the chemical changes experienced by the drilling mud. Conversely, BHR reading serves as a baseline to assess the extent of the performance drawback of the drilling mud after thermal degradation. Figure 2 presents the rheological properties of WBMs with 0.5g of sonicated and as-received GNPs compared with the controlled WBMs. The overall rheological properties of controlled mud and GNPs added WBMs exhibited a reduction under AHR. The reduction is primarily due to the degradation of viscosifier effectiveness, such as xanthan gum and PAC-HP, under elevated temperature and pressure. Similar findings have been observed in study [ 9 ], [ 23 ], [ 32 ]. Nevertheless, the mud containing sonicated GNPs demonstrates a notable improvement with an 18% increase in YP, followed by a 33.33% improvement in gel strength. These improvements are attributed to the formation of a network structure between the well-dispersed GNPs with the remaining polymer clay materials, contributing to a greater rheological performance under AHR conditions. In contrast, mud formulated with as-received GNPs exhibited greater improvement across rheological parameters. This behaviour is attributed not to enhanced structural interactions but rather to agglomeration. Poorly dispersed GNPs formed large clusters with polymers and weighting materials, which restricted fluid movement. This mechanical resistance resulted in higher apparent viscosity and gel strength, reflecting mud thickening by physical clumping rather than true reinforcement of the fluid microstructure. Filtration Properties Figure 3 presents the LPLT and HPHT filtrate loss and mud cake thickness of GNPs added mud and base mud after 30 minutes. Overall, the incorporation of GNPs into the WBMs demonstrates a reduction in the filtrate volume and mud cake thickness compared to the base mud. Under LPLT conditions, sonicated GNPs in particular demonstrate a better performance in AHR with the reduction in fluid loss by 4% from 7.5ml to 7.2ml and mud cake thickness by 21.39% from 0.72mm to 0.566mm. Additionally, Figs. 3 (c) and 3(d) show that the addition of 0.5g sonicated GNPs resulted in a fluid loss reduction by 13.6% from 22ml to 19ml and mud cake thickness by 36.7% from 4.85mm to 3.07mm under HPHT conditions. A summary of the percentage improvements between as-received and sonicated GNPs is provided in Table S6. The improvement in filtrate loss control and mud cake thickness is attributed to the nanoscale dimensions of GNPs, which enable them to occupy micropores within the polymer matrix and filter medium, forming a compact and impermeable barrier that restricts filtrate invasion. In contrast, as-received GNPs show a limited contribution to the filtration properties of mud attributed to their larger lateral size, which hinders their ability to fit tightly into micropores between the polymer matrix and bridging materials such as calcium carbonate, as evidenced by the SEM images in Fig. 4 (a) and 4(c). SEM analysis revealed that as-received GNPs show a bigger lateral size of 10.16µm and 9.825µm compared with the sonicated GNPs of 5.695µm and 2.680µm. The loose fit of the larger GNPs particles resulted in small voids in between that still allow the filtrate to penetrate through, thereby reducing their sealing efficiency. Another notable finding is that GNPs exhibited a better performance under HPHT conditions compared with LPLT. This improvement is attributed to higher pressure driving the network sheets of nanoscale GNPs to compress more tightly and plugging the pores of the filter medium. 3.3 Performance of WBMs with Varying Concentration of Sonicated GNPs Rheological Properties Figure 5 presents the overall rheological properties consisting of PV, YP, and gel strength for WBMs with varying concentrations of sonicated GNPs. PV is defined as the measurement of the fluid resistance to flow due to the mechanical friction between the fluid. It shows an infinitesimal increase from 12cP to a maximum of 13 cP with the addition of GNPs concentrations. This increment is attributed to the gelatinization of starch molecules, which absorb water, swell, and form partial crosslinking networks with graphene, thereby contributing to higher PV [ 33 ]. However, this effect is limited, attributed to the degradation of starch molecules during hot rolling at 250°F (121°C), which reduces their viscosity contribution. With the degraded starch molecules, the cross-linking effect with the GNPs is weak and does not yield as obvious an effect of PV as before. Referring to Fig. 5 , YP, which measures the initial stress required to initiate the flow in the drilling mud [ 14 ] shows a 36.36% increase from 11lb/100 \(\:{\text{f}\text{t}}^{2}\) to 15lb/100 \(\:{\text{f}\text{t}}^{2}\) . Proper sonication deflocculates the GNPs into a large surface area with a high aspect ratio, and they engage with other polymer additives and solid particles through van der Waals forces of interactions that might help in increasing the YP [ 19 ]. These nanoscale and thin-plate-like GNPs can physically interlock or entangle with the clay particles and polymer chains in creating a network structure, which increases the stress and structural resistance that are needed to break the initial static structure. GS is defined as the drilling fluid’s ability to suspend the drill cuttings under static conditions. Figure 5 shows a modest increment of GS with 33% improvement from 3cP to 4cP. However, given the low baseline values, the improvement falls within the potential range of experimental error, suggesting that a higher baseline of GS values would allow for more conclusive analysis. Taking into consideration PY, YP, and GS, 0.4g of GNPs shows a better rheological enhancement. Further increase in the GNPs concentration resulted in agglomeration of GNPs. It shows a reduction in PV and YP and does not contribute positively to the rheological properties [ 27 ]. Importantly, the rheological properties fall within the recommended performance specifications outlined in Table S7, as suggested by Katende et.al., indicating that the formulated mud is suitable for field application. Filtration Properties Filtration loss refers to the volume of filtrate that migrates from drilling fluid into the formation. Excessive filtrate invasion can destabilize the wellbore by inducing clay swelling in WBMs, leading to elevated equivalent circulating density (ECD) and the possibility of stuck pipe [ 17 ]. Figure 6 presents an overview of the mud filtration properties under AHR and BHR conditions. AHR value is given more emphasis compared to the BHR value as it reflects downhole conditions and the chemical changes experienced by the drilling mud. Overall, the increase in GNPs concentration reduced both filtration loss and mud cake thickness. Referring to Fig. 6 , 0.4 g of GNPs shows a 6.67% reduction in LPLT fluid loss from 7.5ml to 7.0ml and a 16.36% reduction in HPHT fluid loss from 22.0ml to 18.4ml. These reductions are attributed to the rapid sealing of the pores by GNPs [ 17 ], [ 22 ], [ 27 ]. At 0.5g of GNPs, the filtration volume increased slightly, recorded at 7.2ml, indicating that concentrations beyond the optimum level promote GNPs agglomeration, thereby reducing sealing efficiency. Filter cake thickness refers to the layers of solid particles that form on the wall of the borehole or filter paper, which helps in bridging and plugging the pores of the formation [ 17 ]. With 0.4g of GNPs. Figure 6 shows a 17.08% and 21.44% reduction in LPLT and HPHT filter cake thickness. This improvement is attributed to the rapid bridging of the filter cake due to an increase in GNPs concentration, resulting in a thinner, impermeable, and more compact filter cake. Furthermore, a greater reduction in mud cake thickness was observed under HPHT conditions with similar concentrations of GNPs added. High pressure compacted the nanosheet network of GNPs into micropores, forming a tighter and more compact filter cake [ 17 ]. Although 0.5g of GNPs yielded further reduction of filter cake thickness, the overall performance, considering rheological properties and filtrate control, indicated that 0.4 g was the optimal concentration. Most importantly, the filtration properties fall within the recommended performance specifications outlined in Table S8. Overall, the findings demonstrate that the incorporation of GNPs significantly improves the rheological and filtration properties of WBMs. Tested under AHR conditions, the addition of 0.4 g sonicated GNPs resulted in the most significant improvements, with up to 36.36% increase in yield point and reductions of 16.36% in HPHT fluid loss and 21.44% in mud cake thickness. Sonication effectively deflocculated the two-dimensional layered structures, increasing their surface area and enabling stronger interactions with both the base fluid and mud additives through van der Waals forces. This enhanced interaction promoted higher yield point and gel strength, as the nanoplatelets formed interconnected networks capable of stabilizing cuttings and weighting agents in suspension under static and low-shear conditions. Simultaneously, the crosslinking effects and intrinsic lubricating nature of graphene layers supported shear-thinning behaviour, maintaining plastic viscosity at manageable levels for efficient pumping. In addition, nanoscale size GNPs tended to align under differential pressure and filled the micropores of the polymer matrix, forming a compact, low-permeability filter cake that reduced filtrate invasion. Collectively, these mechanisms highlight the synergistic role of GNPs in improving both the flow behaviour and filtration control of WBMs. 4.0 Conclusion In conclusion, this research has demonstrated the potential of GNPs as an alternative rheological optimization and fluid loss control agent, particularly under HPHT conditions. In this study, WBMs with GNPs added at a concentration of 0.1ppb – 0.5ppb are tested after the hot rolling with the conditions of (250°F, 150 psi, and dynamic rolling of 16h). At the optimum concentration of 0.4g GNPs, the results show that drilling mud can effectively improve its yield point (YP) by 36.36%, accompanied by 6.67% and 17.08% reduction in LPLT fluid loss and filter cake thickness. A similar effect was observed under HPHT conditions with a 16.36% reduction in fluid loss and 21.44% reduction in mud cake thickness. These enhancements are attributed to the stronger interaction of GNPs with the polymer clay matrix and the ability of their nanoscale size to clog the micropores of the filter medium. Sonication was shown to play a critical role in enhancing GNP performance by deflocculating platelets into thinner sheets and improving dispersion within the WBM. Compared with as-received GNPs, sonicated GNPs achieved additional reductions of 2.7% and 13.5% in LPLT filtrate loss and mud cake thickness, as well as 9.1% and 26.4% in HPHT filtrate loss and mud cake thickness. In contrast, as-received GNPs exhibited limited improvements due to agglomeration and poor dispersion, where viscosity increases were primarily attributed to mechanical thickening rather than structural reinforcement. Overall, these findings highlight that proper dispersion and optimum concentration of GNPs are critical for maximizing their performance in drilling fluid applications. Sonicated GNPs not only improve the rheological stability of WBMs but also significantly enhance fluid loss and mud cake thickness control, making them a promising additive for WBMs formulations in HPHT drilling operations. Declarations Declaration of Interest Statement The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Author Contribution Kai Chen Wong – Main contributor; performed the experiments, data analysis, and led the writing of the manuscript.Veeradasan Perumal – Provided guidance, conceptualization, review, and critical revisions.Muhammad Aslam Bin Md Yusof – Provided technical guidance, methodology support, and manuscript review.Sathiasegkaran Muthumanickam – Contributed practical insights, resources, and validation from an industrial perspective.Mark Ovinis – Contributed to manuscript review, technical feedback, and editing.Saravanan Karuppanan – Contributed to validation and technical discussions.Pandian Bothi Raja – Contributed to resources, conceptualization, and reviewing.Mohamad Nasir Mohamad Ibrahim – Contributed to resources and review.Natarajan Arumugam – Contributed to manuscript review, suggestions, and additional technical input. Acknowledgements The authors would like to acknowledge funding from Malaysia Thailand Joint Authority-MTJA (Grant No: 015QB0-349). The contributions and efforts of the team and staff at UTP’s Department of Mechanical Engineering, UTP’s Department of Petroleum Engineering, and the Centre for Innovative Nanostructures & Nanodevices (COINN) are deeply appreciated. The authors also extend their sincere gratitude to the Ongoing Research Funding Program (ORF-2025-143), King Saud University, Riyadh, Saudi Arabia. References A. S. Apaleke, A. Al-Majed, and M. E. Hossain, “SPE-153676 STATE OF THE ART AND FUTURE TREND OF DRILLING FLUID: AN EXPERIMENTAL STUDY,” 2012. C. Zamora-Ledezma et al. , “Vermiculite and graphene oxide 2D layered nanoparticle for improving rheology and filtration in water-based drilling fluids formulations,” Results in Engineering , vol. 26, Jun. 2025, doi: 10.1016/j.rineng.2025.104796. A.Belani and S. Orr, “A systematic approach to hostile environments,” Journal of Petroleum Technology, vol. 60, no. 07, pp. 34–39, Jul. 2008, doi: 10.2118/0708-0034-jpt. S. Davoodi, M. Al-Shargabi, D. A. Wood, V. S. 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Lu et al. , “Research and Test on the Device of Downhole Near-Bit Temperature and Pressure Measurement While Drilling,” Processes , vol. 11, no. 8, Aug. 2023, doi: 10.3390/pr11082238. S. U. Kadam, B. K. Tiwari, and C. P. O’Donnell, “Improved thermal processing for food texture modification,” in Modifying Food Texture: Novel Ingredients and Processing Techniques , 2015. doi: 10.1016/B978-1-78242-333-1.00006-1. Additional Declarations No competing interests reported. Supplementary Files Supplementary.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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1","display":"","copyAsset":false,"role":"figure","size":241766,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic illustration of the procedure to prepare sonicated GNPs.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-7692464/v1/0fc3711658c18a43b2b8bcf0.png"},{"id":94701295,"identity":"b2ef8bd9-eeec-44dc-9441-37f480730138","added_by":"auto","created_at":"2025-10-29 19:53:51","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":404494,"visible":true,"origin":"","legend":"\u003cp\u003eThe effect of as-received GNPs and sonicated GNPs on rheological properties.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-7692464/v1/924648fd4069dc5ceba995c0.png"},{"id":94701311,"identity":"f29aa552-9f75-4cf2-af09-60f69443431b","added_by":"auto","created_at":"2025-10-29 19:53:54","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":595435,"visible":true,"origin":"","legend":"\u003cp\u003eLPLT (a) fluid loss, (b) mud cake thickness, and HPHT (c) fluid loss, (d) mud cake thickness of as-received, sonicated GNPs, and control mud.\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-7692464/v1/7eaa0bb2f9938250267bda74.png"},{"id":94701315,"identity":"7309717c-318b-49d5-8cf9-c7e2b5c1f806","added_by":"auto","created_at":"2025-10-29 19:53:54","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":645755,"visible":true,"origin":"","legend":"\u003cp\u003eSEM images of LPLT mud cake with (a) as-received GNPs and (b) sonicated GNPs.\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-7692464/v1/3e51167ef73cc7df826fa8cf.png"},{"id":94701309,"identity":"6966d77d-b6bb-4fe7-90b6-52da671e32cc","added_by":"auto","created_at":"2025-10-29 19:53:54","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":629471,"visible":true,"origin":"","legend":"\u003cp\u003eThe effect of varying concentrations of GNPs on rheological properties (AHR).\u003c/p\u003e","description":"","filename":"Figure5.png","url":"https://assets-eu.researchsquare.com/files/rs-7692464/v1/320eef59fdea5632ea2fd908.png"},{"id":94701303,"identity":"e0ed6737-5ce6-4b6c-9894-74b56187a3e9","added_by":"auto","created_at":"2025-10-29 19:53:53","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":873687,"visible":true,"origin":"","legend":"\u003cp\u003eLPLT (a) fluid loss, (b) mud cake thickness, and HPHT (c) fluid loss, (d) mud cake thickness of varying concentrations of GNPs.\u003c/p\u003e","description":"","filename":"Figure6.png","url":"https://assets-eu.researchsquare.com/files/rs-7692464/v1/65420bdb235c2af06f177e25.png"},{"id":96246364,"identity":"f7d03e52-5ce5-470d-bdef-3f7ddef01ff2","added_by":"auto","created_at":"2025-11-19 07:25:37","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4044034,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7692464/v1/1fd26461-f89b-4bd6-a992-f7d2c8bc2b7b.pdf"},{"id":94701312,"identity":"1d737f2e-309c-4902-8b2b-5e96a8d93201","added_by":"auto","created_at":"2025-10-29 19:53:54","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":424965,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementary.docx","url":"https://assets-eu.researchsquare.com/files/rs-7692464/v1/150c96fab7c2f71e0924b355.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Influence of Sonication and Graphene Nanoplatelets Concentration on Rheological and Filtration Properties of Water-based Mud","fulltext":[{"header":"1.0 Introduction","content":"\u003cp\u003eDrilling fluid is defined as a composite fluid that facilitates the formulation and abstraction of cuttings from a drilling borehole. It serves as a lubricant for the drilling bits, maintaining the subsurface pressure, reducing friction between the drilling string and the wellbore side, and carrying the cuttings from beneath the bit, transporting them up to the annulus [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Over the past few decades, research on drilling fluid formulations has continued to evolve to address the fluid loss control and rheology optimization associated with high-pressure, high-temperature (HPHT) drilling environments [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. With the declining oil and gas reserves in onshore and shallow offshore regions, coupled with the rising demand for natural gas and crude oil worldwide, deeper well drilling, especially under HPHT conditions, has become increasingly vital. Currently, three drilling fluids are widely considered for the wellbore drilling process, namely Oil-based Mud (OBM), Water-based Mud (WBM), and Synthetic-based Mud (SBM). While water-based muds (WBMs) are more cost-effective [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] and environmentally friendly than oil-based alternatives, they often underperform in extreme conditions due to shale swelling [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Shale swelling elevates the equivalent circulation density (ECD), which may lead to a significant operational challenge, such as stuck pipe, reduction of hole cleaning efficiency, and the possible collapse of the wellbore when the level surpasses the formation\u0026rsquo;s fracture gradient [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn earlier days, polymeric additives such as polyanionic cellulose (PAC), carboxymethyl cellulose (CMC), and xanthan gum (XC) were commonly used to enhance the performance of WBMs. However, they demonstrated limited thermal stability [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], and poor rheological and filtration properties under harsh condition [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Moreover, fine calcium carbonate asphalt that is used conventionally as a plugging agent is of a micron scale, which limits its effectiveness in forming a compact and impermeable filter membrane in preventing excessive filtrate loss [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. A detailed comparison is provided in Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e. Based on these notions, several studies have investigated the potential of nanomaterials as promising additives[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] with GNPs standing out due to their excellent thermal stability up to 650\u0026deg;C, high specific surface area, and mechanical strength [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Research indicates that GNPs can improve plastic viscosity (PV), yield point (YP), and reduce both mud cake thickness and fluid loss [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Graphene is a single layer of two-dimensional (2D) carbon atoms arranged in a tightly packed hexagonal honeycomb lattice [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Due to its unique structure, the 2D lattice structure of graphene can be wrapped up into fullerene (zero-dimensional, 0D), rolled up into a carbon nanotube (one-dimensional, 1D), or stacked to form graphite [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Graphene itself appears in black, fine, shiny powder. It is hydrophobic and chemically inert. There are several types of graphene due to the variations in the number of layers, lateral dimension, and surface chemistry of graphene materials. These include graphene nanoplatelets (GNP), graphene oxide (GO), few layers of graphene, etc [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eWhile preparing the graphene, mechanical exfoliation via ultrasonic sonication is widely used in drilling fluid studies because it is cost-effective and simple, despite the struggles for large-scale production [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. While several studies have reported the parameters employed in the sonication preparation of GNPs and other graphene-based materials [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e], [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e], [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], the methodologies, including time, power, and temperature vary considerably, and it is not clearly reported. In particular, although sonication is frequently applied as a dispersion technique, there has been no systematic investigation comparing the performance of sonicated versus as-received GNPs in drilling fluid formulations. This gap raises uncertainty regarding the necessity of sonication and its actual impact on drilling fluid performance.\u003c/p\u003e\u003cp\u003eOn the contrary, some studies provide only qualitative descriptions of GNP preparation, such as manual stirring to ensure apparent homogeneity, without systematic consideration of key parameters. Certain cases of research even only apply stirring with a high-speed mixer for as little as 15 minutes to confirm the homogeneous dispersion of graphene [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Table S2 shows the summary of graphene sonication parameters and observation details from a few studies. In addition, a study conducted by Zhang on the dispersion effect of GNPs found that temperature control contributes to the exfoliation degree of the GNPs [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Temperatures higher than 35℃ will reduce the degree of exfoliation, but none of this was mentioned in the studies of graphene-added materials used for drilling fluids.\u003c/p\u003e\u003cp\u003eThis study aims to provide a new insight into investigating the performance of as-received and sonicated GNPs on rheological and filtration properties of WBMs. GNPs are first characterised by SEM-EDX analysis. Besides, independent variables including sonication power, temperature, duration, and GNPs concentration are well-optimised to produce quality sonicated GNPs. The latter that exhibits a better performance is further analysed across varying concentrations from 0.1g to 0.5g to assess the influence of GNPs concentration on the rheological and filtration properties. Overall, the structure of the study takes the form of four chapters, including introduction, methodology, results and discussion, as well as conclusion.\u003c/p\u003e"},{"header":"2.0 Methodology","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1 Materials\u003c/h2\u003e\u003cp\u003eGraphene nanoplatelets (GNPs) with CAS Number 7782-42-5 were procured from Nanografi. They appeared as a fine black powder with an average diameter of 30\u0026micro;m, 5nm size, and an average surface area of 170 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{m}^{2}\\)\u003c/span\u003e\u003c/span\u003e/g. Table S3 shows the function of the mud additives for the drilling mud. Drill water was used as a base fluid to dissolve other mud additives for the preparation of drilling mud. API bentonite was added to provide wellbore stability, while potassium chloride served as a shale inhibitor and provided salinity, and sodium hydroxide functioned to increase the alkalinity of the drilling mud. Xanthan gum functioned as the primary viscosifier and high-purity polyanionic cellulose (PAC-HP) as the secondary viscosifier. Fluid loss control agents included low-viscosity polyanionic cellulose (hydro-PAC-LV), high-purity polyanionic cellulose (PAC-HP), modified starch (OPTA-STAR), and GNPs. Calcium carbonate was incorporated as a bridging agent, and barite was used as a weighing agent, contributing to the desired mud density of the drilling fluids.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2 Equipment\u003c/h2\u003e\u003cp\u003eAll the mud additives were weighed using an electronic balance before it is mixed to ensure uniform distribution. The mixing process was carried out using a Fann Five Spindle Multimixer Model 9B. Sonication of the GNPs was performed using an Xiang Yi Ultrasonic Homogeniser. Rheological properties of the WBMs were then determined by using a Fann 35SA Viscometer following mud density measurement using a FANN Mud Balance Model 140. In addition, the filtration properties of the WBMs were evaluated using the TEMCO LPLT Filter Press and OFITE HPHT Filter Press. The entire procedure was repeated after hot rolling of mud using the Fann Roller Oven.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3 GNPs Preparation\u003c/h2\u003e\u003cp\u003eThe preparation method for GNPs is done by mechanical exfoliation through sonication, referencing a few research papers. GNPs with a weight ranging from 0.1g to 0.5g were sonicated in 100 mL of water for 1 hour. 100 ml of water is treated with 0.1g of surfactants (sodium carboxymethyl cellulose) to ensure a better dispersion of GNPs [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Prior to sonication, magnetic stirrer was used to stir and dissolve the surfactants for about 15 minutes. Sonication was performed using a pulsed mode of 10 seconds on and 10 seconds off, with a power output of 400W and a probe frequency of around 22kHz. The temperature of the solution is controlled below 35℃ to ensure better deflocculation efficiency.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003e2.4 Mud Preparation\u003c/h2\u003e\u003cp\u003eThe drilling muds were prepared according to the procedures outlined in Table S4 and Table S5. Initially, 230ml of drill water was placed into the multimixer cup, followed by the addition of 0.2g of soda ash and 5g of API bentonite. Next, 0.2g of sodium hydroxide and 12g of potassium chloride were added to the formulation. 1.5g of hydro-PAC-LV and 1g of PAC-HP were then added to the mud before adding 0.8g of xanthan gum, 0.25g of CMC-LV, and 1g of OPTASTAR. Each of the additives added above was mixed for 5 minutes before another additives were added. After that, 10g of calcium carbonate was added and mixed for 15 minutes, followed by 17g of barite, which was mixed for 25 minutes. The procedure above was repeated to prepare mud containing different concentrations of GNPs, varying from 0.1g to 0.5g.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003e2.5 Rheological Testing\u003c/h2\u003e\u003cp\u003eRheology tests were conducted in accordance with API RP 13B-1 [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e] using a Fann 35A Viscometer, where dial readings at \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\theta\\:}_{600}\\)\u003c/span\u003e\u003c/span\u003e, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\theta\\:}_{300}\\)\u003c/span\u003e\u003c/span\u003e, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\theta\\:}_{200}\\)\u003c/span\u003e\u003c/span\u003e, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\theta\\:}_{100}\\)\u003c/span\u003e\u003c/span\u003e, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\theta\\:}_{6}\\)\u003c/span\u003e\u003c/span\u003e, and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\theta\\:}_{3}\\)\u003c/span\u003e\u003c/span\u003e were recorded for analysis. The readings of 10s gel strength and 10 min gel strength were taken at \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\theta\\:}_{3}\\)\u003c/span\u003e\u003c/span\u003e rpm after the formulated drilling muds were allowed to rest for 10 seconds and 10 minutes. Plastic viscosity (PV), and yield point (YP) can then be calculated using the following formula:\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$\\:PV=\\:{\\theta\\:}_{600}-\\:{\\theta\\:}_{300}$$\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Equb\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equb\" name=\"EquationSource\"\u003e\n$$\\:YP=\\:{\\theta\\:}_{300}-PV$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003e2.6 Filtration Testing\u003c/h2\u003e\u003cp\u003eFiltration characteristics of the drilling mud were evaluated in accordance with API RP 13B-1 [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e] using the TEMCO LPLT Filter Press Cell and the OFITE HPHT Filter Press Cell. For the LPLT tests, a filter paper with an effective area of 7.1 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\text{i}\\text{n}}^{2}\\)\u003c/span\u003e\u003c/span\u003e was employed, while the HPHT tests utilized a filter paper with an effective area of 3.5 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\text{i}\\text{n}}^{2}\\)\u003c/span\u003e\u003c/span\u003e. The LPLT filtration tests were conducted at ambient temperature under a pressure of 100 psi, while the HPHT filtration tests were conducted at a 500 psi differential pressure and a temperature of 250\u0026deg;F. The selected HPHT conditions served as a preliminary screen to quantify the baseline impact of GNPs on filtration properties before subsequent evaluation at ultra HPHT conditions. After 30 minutes of testing, the volume of filtrate loss was recorded. Subsequently, the filter cake was carefully retrieved, and its average thickness was measured using a digital vernier calliper.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\u003ch2\u003e2.7 GNPs Characterisation\u003c/h2\u003e\u003cp\u003eScanning Electron Microscopy (SEM) with Energy Dispersive X-ray Analysis (EDX) was used for the analysis of the GNPs. By directing a finely focused beam of high-energy electrons onto the surface of the specimen and capturing the signals from secondary electrons and backscattered electrons, SEM can generate high-resolution images up to the magnification of 5.00 kx. Besides, EDX analysis provides an elemental analysis and chemical characterisation of the sample.\u003c/p\u003e\u003c/div\u003e"},{"header":"3.0 Results and Discussion","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e3.1 Characterisation of GNPs\u003c/h2\u003e\u003cp\u003eFigure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e illustrates the images from scanning electron microscopy (SEM) and Energy Dispersive X-ray Analysis (EDX). Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e(a) of SEM micrographs revealed that the GNPs exhibit a broad size distribution with agglomerated morphologies. Further detailed picture in Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e(b) shows stacked multilayer GNP sheets with overlapping regions, further confirming the occurrence of agglomeration. The stacked and agglomerated structure of GNPs suggests a reduced surface interaction with the surrounding medium, which may influence its dispersibility. Nevertheless, sharp edges and smooth surfaces observed in the SEM images highlight the distinctive features of GNPs [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] The latter characteristics is particularly beneficial in drilling applications, as smooth graphene planes can reduce the friction between the drill pipe and the wellbore, thereby lowering the torque and drag [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eAdditionally, the EDX analysis in Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e(c) confirmed the high purity of the GNPs, with carbon and oxygen contents measured at 82.12 wt.% and 17.88 wt.%, respectively. This composition suggests minimal contamination from metallic catalysts or other residues, thereby ensuing the chemical stability under downhole conditions. Overall, the morphological features of GNPs observed are expected to play a crucial role in improving fluid loss control and rheological optimization of WBMs.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003e3.2 Performance of as-received GNPs and Sonicated GNPs with the same Concentration\u003c/h2\u003e\u003cp\u003e\u003cb\u003eRheological Properties\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe rheological properties of mud with sonicated and as-received GNPs were tested under two conditions: before hot rolling (BHR) and after hot rolling (AHR). The rheological readings were measured following hot rolling at 250\u0026deg;F and 150 psi for 16h. Hot rolling simulates the mud performance under elevated temperature and pressure of the borehole. During dynamic rolling, WBMs are constantly circulating to simulate the shear stress experienced by the drilling fluids when circulating the wellbore. It provides a more realistic representation of downhole conditions compared with static hot rolling. Therefore, the AHR value is commonly given more emphasis compared to the BHR value as it simulates more accurate downhole conditions and the chemical changes experienced by the drilling mud. Conversely, BHR reading serves as a baseline to assess the extent of the performance drawback of the drilling mud after thermal degradation.\u003c/p\u003e\u003cp\u003eFigure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e presents the rheological properties of WBMs with 0.5g of sonicated and as-received GNPs compared with the controlled WBMs. The overall rheological properties of controlled mud and GNPs added WBMs exhibited a reduction under AHR. The reduction is primarily due to the degradation of viscosifier effectiveness, such as xanthan gum and PAC-HP, under elevated temperature and pressure. Similar findings have been observed in study [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e], [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Nevertheless, the mud containing sonicated GNPs demonstrates a notable improvement with an 18% increase in YP, followed by a 33.33% improvement in gel strength. These improvements are attributed to the formation of a network structure between the well-dispersed GNPs with the remaining polymer clay materials, contributing to a greater rheological performance under AHR conditions.\u003c/p\u003e\u003cp\u003eIn contrast, mud formulated with as-received GNPs exhibited greater improvement across rheological parameters. This behaviour is attributed not to enhanced structural interactions but rather to agglomeration. Poorly dispersed GNPs formed large clusters with polymers and weighting materials, which restricted fluid movement. This mechanical resistance resulted in higher apparent viscosity and gel strength, reflecting mud thickening by physical clumping rather than true reinforcement of the fluid microstructure.\u003c/p\u003e\u003cp\u003e\u003cb\u003eFiltration Properties\u003c/b\u003e\u003c/p\u003e\u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e presents the LPLT and HPHT filtrate loss and mud cake thickness of GNPs added mud and base mud after 30 minutes. Overall, the incorporation of GNPs into the WBMs demonstrates a reduction in the filtrate volume and mud cake thickness compared to the base mud. Under LPLT conditions, sonicated GNPs in particular demonstrate a better performance in AHR with the reduction in fluid loss by 4% from 7.5ml to 7.2ml and mud cake thickness by 21.39% from 0.72mm to 0.566mm. Additionally, Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e(c) and 3(d) show that the addition of 0.5g sonicated GNPs resulted in a fluid loss reduction by 13.6% from 22ml to 19ml and mud cake thickness by 36.7% from 4.85mm to 3.07mm under HPHT conditions. A summary of the percentage improvements between as-received and sonicated GNPs is provided in Table S6.\u003c/p\u003e\u003cp\u003eThe improvement in filtrate loss control and mud cake thickness is attributed to the nanoscale dimensions of GNPs, which enable them to occupy micropores within the polymer matrix and filter medium, forming a compact and impermeable barrier that restricts filtrate invasion. In contrast, as-received GNPs show a limited contribution to the filtration properties of mud attributed to their larger lateral size, which hinders their ability to fit tightly into micropores between the polymer matrix and bridging materials such as calcium carbonate, as evidenced by the SEM images in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e(a) and 4(c). SEM analysis revealed that as-received GNPs show a bigger lateral size of 10.16\u0026micro;m and 9.825\u0026micro;m compared with the sonicated GNPs of 5.695\u0026micro;m and 2.680\u0026micro;m. The loose fit of the larger GNPs particles resulted in small voids in between that still allow the filtrate to penetrate through, thereby reducing their sealing efficiency.\u003c/p\u003e\u003cp\u003eAnother notable finding is that GNPs exhibited a better performance under HPHT conditions compared with LPLT. This improvement is attributed to higher pressure driving the network sheets of nanoscale GNPs to compress more tightly and plugging the pores of the filter medium.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003e3.3 Performance of WBMs with Varying Concentration of Sonicated GNPs\u003c/h2\u003e\u003cp\u003e\u003cb\u003eRheological Properties\u003c/b\u003e\u003c/p\u003e\u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e presents the overall rheological properties consisting of PV, YP, and gel strength for WBMs with varying concentrations of sonicated GNPs. PV is defined as the measurement of the fluid resistance to flow due to the mechanical friction between the fluid. It shows an infinitesimal increase from 12cP to a maximum of 13 cP with the addition of GNPs concentrations. This increment is attributed to the gelatinization of starch molecules, which absorb water, swell, and form partial crosslinking networks with graphene, thereby contributing to higher PV [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. However, this effect is limited, attributed to the degradation of starch molecules during hot rolling at 250\u0026deg;F (121\u0026deg;C), which reduces their viscosity contribution. With the degraded starch molecules, the cross-linking effect with the GNPs is weak and does not yield as obvious an effect of PV as before.\u003c/p\u003e\u003cp\u003eReferring to Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e, YP, which measures the initial stress required to initiate the flow in the drilling mud [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] shows a 36.36% increase from 11lb/100\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\text{f}\\text{t}}^{2}\\)\u003c/span\u003e\u003c/span\u003e to 15lb/100\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\text{f}\\text{t}}^{2}\\)\u003c/span\u003e\u003c/span\u003e. Proper sonication deflocculates the GNPs into a large surface area with a high aspect ratio, and they engage with other polymer additives and solid particles through van der Waals forces of interactions that might help in increasing the YP [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. These nanoscale and thin-plate-like GNPs can physically interlock or entangle with the clay particles and polymer chains in creating a network structure, which increases the stress and structural resistance that are needed to break the initial static structure.\u003c/p\u003e\u003cp\u003eGS is defined as the drilling fluid\u0026rsquo;s ability to suspend the drill cuttings under static conditions. Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e shows a modest increment of GS with 33% improvement from 3cP to 4cP. However, given the low baseline values, the improvement falls within the potential range of experimental error, suggesting that a higher baseline of GS values would allow for more conclusive analysis.\u003c/p\u003e\u003cp\u003eTaking into consideration PY, YP, and GS, 0.4g of GNPs shows a better rheological enhancement. Further increase in the GNPs concentration resulted in agglomeration of GNPs. It shows a reduction in PV and YP and does not contribute positively to the rheological properties [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Importantly, the rheological properties fall within the recommended performance specifications outlined in Table S7, as suggested by Katende et.al., indicating that the formulated mud is suitable for field application.\u003c/p\u003e\u003cp\u003e\u003cb\u003eFiltration Properties\u003c/b\u003e\u003c/p\u003e\u003cp\u003eFiltration loss refers to the volume of filtrate that migrates from drilling fluid into the formation. Excessive filtrate invasion can destabilize the wellbore by inducing clay swelling in WBMs, leading to elevated equivalent circulating density (ECD) and the possibility of stuck pipe [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e presents an overview of the mud filtration properties under AHR and BHR conditions. AHR value is given more emphasis compared to the BHR value as it reflects downhole conditions and the chemical changes experienced by the drilling mud.\u003c/p\u003e\u003cp\u003eOverall, the increase in GNPs concentration reduced both filtration loss and mud cake thickness. Referring to Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e, \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e0.4\u003c/span\u003eg of GNPs shows a 6.67% reduction in LPLT fluid loss from 7.5ml to 7.0ml and a 16.36% reduction in HPHT fluid loss from 22.0ml to 18.4ml. These reductions are attributed to the rapid sealing of the pores by GNPs [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. At 0.5g of GNPs, the filtration volume increased slightly, recorded at 7.2ml, indicating that concentrations beyond the optimum level promote GNPs agglomeration, thereby reducing sealing efficiency.\u003c/p\u003e\u003cp\u003eFilter cake thickness refers to the layers of solid particles that form on the wall of the borehole or filter paper, which helps in bridging and plugging the pores of the formation [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. With 0.4g of GNPs. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e shows a 17.08% and 21.44% reduction in LPLT and HPHT filter cake thickness. This improvement is attributed to the rapid bridging of the filter cake due to an increase in GNPs concentration, resulting in a thinner, impermeable, and more compact filter cake. Furthermore, a greater reduction in mud cake thickness was observed under HPHT conditions with similar concentrations of GNPs added. High pressure compacted the nanosheet network of GNPs into micropores, forming a tighter and more compact filter cake [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Although 0.5g of GNPs yielded further reduction of filter cake thickness, the overall performance, considering rheological properties and filtrate control, indicated that 0.4 g was the optimal concentration. Most importantly, the filtration properties fall within the recommended performance specifications outlined in Table S8.\u003c/p\u003e\u003cp\u003eOverall, the findings demonstrate that the incorporation of GNPs significantly improves the rheological and filtration properties of WBMs. Tested under AHR conditions, the addition of 0.4 g sonicated GNPs resulted in the most significant improvements, with up to 36.36% increase in yield point and reductions of 16.36% in HPHT fluid loss and 21.44% in mud cake thickness. Sonication effectively deflocculated the two-dimensional layered structures, increasing their surface area and enabling stronger interactions with both the base fluid and mud additives through van der Waals forces. This enhanced interaction promoted higher yield point and gel strength, as the nanoplatelets formed interconnected networks capable of stabilizing cuttings and weighting agents in suspension under static and low-shear conditions. Simultaneously, the crosslinking effects and intrinsic lubricating nature of graphene layers supported shear-thinning behaviour, maintaining plastic viscosity at manageable levels for efficient pumping. In addition, nanoscale size GNPs tended to align under differential pressure and filled the micropores of the polymer matrix, forming a compact, low-permeability filter cake that reduced filtrate invasion. Collectively, these mechanisms highlight the synergistic role of GNPs in improving both the flow behaviour and filtration control of WBMs.\u003c/p\u003e\u003c/div\u003e"},{"header":"4.0 Conclusion","content":"\u003cp\u003eIn conclusion, this research has demonstrated the potential of GNPs as an alternative rheological optimization and fluid loss control agent, particularly under HPHT conditions. In this study, WBMs with GNPs added at a concentration of 0.1ppb – 0.5ppb are tested after the hot rolling with the conditions of (250°F, 150 psi, and dynamic rolling of 16h). At the optimum concentration of 0.4g GNPs, the results show that drilling mud can effectively improve its yield point (YP) by 36.36%, accompanied by 6.67% and 17.08% reduction in LPLT fluid loss and filter cake thickness. A similar effect was observed under HPHT conditions with a 16.36% reduction in fluid loss and 21.44% reduction in mud cake thickness. These enhancements are attributed to the stronger interaction of GNPs with the polymer clay matrix and the ability of their nanoscale size to clog the micropores of the filter medium.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSonication was shown to play a critical role in enhancing GNP performance by deflocculating platelets into thinner sheets and improving dispersion within the WBM. Compared with as-received GNPs, sonicated GNPs achieved additional reductions of 2.7% and 13.5% in LPLT filtrate loss and mud cake thickness, as well as 9.1% and 26.4% in HPHT filtrate loss and mud cake thickness. In contrast, as-received GNPs exhibited limited improvements due to agglomeration and poor dispersion, where viscosity increases were primarily attributed to mechanical thickening rather than structural reinforcement.\u003c/p\u003e\n\u003cp\u003eOverall, these findings highlight that proper dispersion and optimum concentration of GNPs are critical for maximizing their performance in drilling fluid applications. Sonicated GNPs not only improve the rheological stability of WBMs but also significantly enhance fluid loss and mud cake thickness control, making them a promising additive for WBMs formulations in HPHT drilling operations.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eDeclaration of Interest Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eKai Chen Wong \u0026ndash; Main contributor; performed the experiments, data analysis, and led the writing of the manuscript.Veeradasan Perumal \u0026ndash; Provided guidance, conceptualization, review, and critical revisions.Muhammad Aslam Bin Md Yusof \u0026ndash; Provided technical guidance, methodology support, and manuscript review.Sathiasegkaran Muthumanickam \u0026ndash; Contributed practical insights, resources, and validation from an industrial perspective.Mark Ovinis \u0026ndash; Contributed to manuscript review, technical feedback, and editing.Saravanan Karuppanan \u0026ndash; Contributed to validation and technical discussions.Pandian Bothi Raja \u0026ndash; Contributed to resources, conceptualization, and reviewing.Mohamad Nasir Mohamad Ibrahim \u0026ndash; Contributed to resources and review.Natarajan Arumugam \u0026ndash; Contributed to manuscript review, suggestions, and additional technical input.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e\u003cp\u003eThe authors would like to acknowledge funding from Malaysia Thailand Joint Authority-MTJA (Grant No: 015QB0-349). The contributions and efforts of the team and staff at UTP\u0026rsquo;s Department of Mechanical Engineering, UTP\u0026rsquo;s Department of Petroleum Engineering, and the Centre for Innovative Nanostructures \u0026amp; Nanodevices (COINN) are deeply appreciated. The authors also extend their sincere gratitude to the Ongoing Research Funding Program (ORF-2025-143), King Saud University, Riyadh, Saudi Arabia.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eA. S. Apaleke, A. Al-Majed, and M. E. Hossain, \u0026ldquo;SPE-153676 STATE OF THE ART AND FUTURE TREND OF DRILLING FLUID: AN EXPERIMENTAL STUDY,\u0026rdquo; 2012.\u003c/li\u003e\n\u003cli\u003eC. 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Tiwari, and C. P. O\u0026rsquo;Donnell, \u0026ldquo;Improved thermal processing for food texture modification,\u0026rdquo; in \u003cem\u003eModifying Food Texture: Novel Ingredients and Processing Techniques\u003c/em\u003e, 2015. doi: 10.1016/B978-1-78242-333-1.00006-1.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Graphene nanoplatelets, high-pressure high-temperature, sonication, water-based muds, thermal aging, fluid loss","lastPublishedDoi":"10.21203/rs.3.rs-7692464/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7692464/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe rising complexity of drilling under high-pressure and high-temperature (HPHT) conditions creates substantial challenges in fluid loss control, thermal stability, and rheological performance for drilling fluids. Nanoparticles, particularly graphene, have garnered tremendous attention as a promising additive to improve the performance of drilling fluids. This study investigates graphene nanoplatelets (GNPs) as a potential novel application to enhance the rheological performance and fluid loss control of WBMs. A comparative analysis of the impact of rheological performance, low-pressure, and low-temperature (LPLT) filtration test, high-pressure, and high-temperature (HPHT) filtration test is presented on WBMs with as-received and sonicated GNPs before tested with varying GNPs concentrations, ranging from 0.1 ppb to 0.5 ppb, under a 9 ppg mud weight. The samples were hot rolled at 250\u0026deg;F and 100psi for 16 hours to evaluate the influence of thermal aging on the properties of the GNPs water-based muds (WBMs). The experimental findings reveal that the mud with sonicated GNPs exhibits better performance, with 9.09% and 26.39% greater reductions in HPHT fluid loss and filter cake thickness, respectively. Besides, optimum concentration of 0.4ppb of GNPs results in a lower filtrate volume in HPHT conditions by 16.36%, and mud cake thickness in both LPLT and HPHT conditions by 17.08% and 21.44% respectively. The yield point has increased by 36.36%, while the plastic viscosity remains unchanged. Overall, this research demonstrates the capabilities of GNPs, particularly when sonicated, in enhancing the performance of WBMs, even at low concentrations, especially under HPHT conditions.\u003c/p\u003e","manuscriptTitle":"Influence of Sonication and Graphene Nanoplatelets Concentration on Rheological and Filtration Properties of Water-based Mud","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-29 19:53:31","doi":"10.21203/rs.3.rs-7692464/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b91deac8-818f-4f65-b929-0a2b1b0e5920","owner":[],"postedDate":"October 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-15T06:53:47+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-29 19:53:31","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7692464","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7692464","identity":"rs-7692464","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}