Synthesis of Nanocellulose Aerogels and Cu-BTC/Nanocellulose Aerogel Composites for Adsorption of Organic Dyes and Heavy Metal Ions

MOFs compounds have great adsorption potential and catalysis applications. However, the powdery morphology limits its applications. To overcome this problem, they can be trapped in a flexible aerogel matrix to form hierarchical porous structures. In this work, Cu-BTC/CNC (crystalline nanocellulose) and Cu-BTC/NFC (nanofibrillated cellulose) aerogel composites were synthesized using a direct mixing method by the addition of Cu-BTC powder to the liquid precursor solution followed by gelation and freeze-drying. Also, pure CNC and NFC aerogels were synthesized using cellulose isolated from peanut shells. All structure and morphology were scrutinized by Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). The adsorption ability of pure CNC and Cu-BTC/NFC for Congo Red (CR) and Mn7 + was studied and determined by the UV-Vis spectrophotometry and inductively-coupled plasma optical emission spectrometry (ICP-OES). The results revealed that Cu-BTC/NFC has excellent adsorption capacity for CR. The adsorption process is well described by the pseudo-second-order kinetic model and Langmuir isotherm, with a maximum adsorption capacity of 39 mg/g for CR. Both CNC and Cu-BTC/NFC act as a solid monolithic reducer and remove MnO4- from aqueous solution by reducing them to manganese dioxide, without releasing any side product.