Ammonia Synthesis through a Pulse Feeding Strategy Provides Insight into Catalytic Reactor Dynamics

Ammonia Synthesis through a Pulse Feeding Strategy Provides Insight into Catalytic Reactor Dynamics | 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 Ammonia Synthesis through a Pulse Feeding Strategy Provides Insight into Catalytic Reactor Dynamics Deniz Üner, Mustafa Yasin Aslan, Justin S. J. Hargreaves This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9245636/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 role of pore condensation on the ammonia synthesis rates is investigated through pulse feeding of the reactants over two different catalysts. One of the catalysts was a 1 wt% Ru/SBA-15, offering a very high and porous surface area. The second catalyst was a very low surface area Co 3 Mo 3 N catalyst with well-defined bulk and surface properties. By sending alternative pulses of H 2 and N 2 mixed with Ar, it was possible to differentiate the role of a porous support and observe surface events. Through a pulse feeding strategy, both reactor hydrodynamics and some of the surface events could be monitored. The transients of Ar in an empty reactor and a reactor packed with Co 3 Mo 3 N exhibited similar behaviours. On the other hand, delayed signals as tails in the derivative response curves over Ru/SBA15 packed reactor indicated pore diffusion effects, even for Ar. Time derivatives of the mass spectrometer signals represent the rates, revealing system-based responses of the reactive species. Ammonia signal from Ru/SBA15 catalyst was congruent with the pulses during the initial period, becoming erratic suggesting cycles of pore condensation, saturation and desorption and finally reaching a steady value reflecting a steady desorption from the pores. On the other hand, ammonia signal from Co 3 Mo 3 N revealed NH 3 signals congruent with the pulses, consistent with the absence of pore condensation. Full Text Additional Declarations No competing interests reported. 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9245636","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":615330832,"identity":"cd240630-36d0-414c-962c-297ee8825403","order_by":0,"name":"Deniz Üner","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAsklEQVRIiWNgGAWjYLCCD1BagmgdjDOgqoGEAXFamHlI0mJwu/nYZ9scmzqDA8wHb/Mw/MknrOXOseTZudvSJAwOsCVb8zAYWDYQ1HIjx5g5d9thoBYeM2mgFsIuM7iR/5nZctt/oBb+b8RqyWFmZtx2AGQLG3FaJG+kGTP2bkuWnHmYzdhyjoExYS18N5IfM/zcZsfPd7z54Y03FXJERgwYMIPdSYKGUTAKRsEoGAW4AQANZTJiOQ1qdAAAAABJRU5ErkJggg==","orcid":"","institution":"Middle East Technical University","correspondingAuthor":true,"prefix":"","firstName":"Deniz","middleName":"","lastName":"Üner","suffix":""},{"id":615330833,"identity":"691c5972-f2b3-452e-9f38-28be52762aeb","order_by":1,"name":"Mustafa Yasin Aslan","email":"","orcid":"","institution":"Middle East Technical University","correspondingAuthor":false,"prefix":"","firstName":"Mustafa","middleName":"Yasin","lastName":"Aslan","suffix":""},{"id":615330834,"identity":"246f7671-362a-4d10-9e66-5d44d799e097","order_by":2,"name":"Justin S. 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One of the catalysts was a 1 wt% Ru/SBA-15, offering a very high and porous surface area. The second catalyst was a very low surface area Co\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN catalyst with well-defined bulk and surface properties. By sending alternative pulses of H\u003csub\u003e2\u003c/sub\u003e and N\u003csub\u003e2\u003c/sub\u003e mixed with Ar, it was possible to differentiate the role of a porous support and observe surface events. Through a pulse feeding strategy, both reactor hydrodynamics and some of the surface events could be monitored. The transients of Ar in an empty reactor and a reactor packed with Co\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN exhibited similar behaviours. On the other hand, delayed signals as tails in the derivative response curves over Ru/SBA15 packed reactor indicated pore diffusion effects, even for Ar. 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