{"title":"Atomistic investigation of porous amorphous materials for CH4/H2 separation","authors":"","doi":"10.1016/j.ces.2024.120741","DOIUrl":null,"url":null,"abstract":"<div><p>Revealing the gas separation capabilities of amorphous porous materials remains a critical challenge in the materials community for their development as novel adsorbents. This work aims to unlock the potential of amorphous materials for adsorption-based CH<sub>4</sub>/H<sub>2</sub> separation at pressure swing adsorption (PSA) condition using grand canonical Monte Carlo (GCMC) simulations. Several adsorbent performance evaluation metrics, including adsorption selectivity, working capacity, adsorbent performance score (APS) and regenerability (R%) were computed at 298 K for polymers of intrinsic microporosity (PIMs), amorphous carbons, kerogens, and amorphous zeolitic imidazole frameworks (ZIFs). The CH<sub>4</sub>/H<sub>2</sub> selectivities and CH<sub>4</sub> working capacities of the amorphous materials were estimated to be 9–62 and 0.1–5 mol/kg under PSA condition. Kerogens exhibited the highest APS, and most of the structures provided high R%>80 %. However, none of the materials could reach the maximum APS (802 mol/kg) of crystalline MOFs. Diffraction pattern analysis of crystalline and amorphous ZIF-4 was also performed, and the structural changes were monitored to independently confirm the amorphization. Although crystalline ZIFs exhibited higher adsorption selectivities for CH<sub>4</sub>/H<sub>2</sub> separation than amorphous ZIFs, their R% were significantly lower. Gas mixture adsorption isotherms of promising amorphous materials were also computed to reveal gas adsorption mechanism. The developed computational approach will be useful in predicting the performance of amorphous materials for CH<sub>4</sub>/H<sub>2</sub> separation under industrial conditions and monitoring amorphization by diffraction analysis during mass production.</p></div>","PeriodicalId":271,"journal":{"name":"Chemical Engineering Science","volume":null,"pages":null},"PeriodicalIF":4.1000,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0009250924010418/pdfft?md5=39c3e507809a218616c9997298a5a7ee&pid=1-s2.0-S0009250924010418-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemical Engineering Science","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0009250924010418","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Revealing the gas separation capabilities of amorphous porous materials remains a critical challenge in the materials community for their development as novel adsorbents. This work aims to unlock the potential of amorphous materials for adsorption-based CH4/H2 separation at pressure swing adsorption (PSA) condition using grand canonical Monte Carlo (GCMC) simulations. Several adsorbent performance evaluation metrics, including adsorption selectivity, working capacity, adsorbent performance score (APS) and regenerability (R%) were computed at 298 K for polymers of intrinsic microporosity (PIMs), amorphous carbons, kerogens, and amorphous zeolitic imidazole frameworks (ZIFs). The CH4/H2 selectivities and CH4 working capacities of the amorphous materials were estimated to be 9–62 and 0.1–5 mol/kg under PSA condition. Kerogens exhibited the highest APS, and most of the structures provided high R%>80 %. However, none of the materials could reach the maximum APS (802 mol/kg) of crystalline MOFs. Diffraction pattern analysis of crystalline and amorphous ZIF-4 was also performed, and the structural changes were monitored to independently confirm the amorphization. Although crystalline ZIFs exhibited higher adsorption selectivities for CH4/H2 separation than amorphous ZIFs, their R% were significantly lower. Gas mixture adsorption isotherms of promising amorphous materials were also computed to reveal gas adsorption mechanism. The developed computational approach will be useful in predicting the performance of amorphous materials for CH4/H2 separation under industrial conditions and monitoring amorphization by diffraction analysis during mass production.
期刊介绍:
Chemical engineering enables the transformation of natural resources and energy into useful products for society. It draws on and applies natural sciences, mathematics and economics, and has developed fundamental engineering science that underpins the discipline.
Chemical Engineering Science (CES) has been publishing papers on the fundamentals of chemical engineering since 1951. CES is the platform where the most significant advances in the discipline have ever since been published. Chemical Engineering Science has accompanied and sustained chemical engineering through its development into the vibrant and broad scientific discipline it is today.