{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T18:59:08Z","timestamp":1790881148575,"version":"4.1.0"},"reference-count":13,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,18]],"date-time":"2018-10-18T00:00:00Z","timestamp":1539820800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Coalbed methane (CBM) is a kind of unconventional gas. CBM often contains a great deal of air when it comes out of the well. So, it must be condensed and purified before it can be applied. In this paper, raw clinoptilolite (Cp) was treated with grinding, gravimetric concentration, and ion-exchange using different aqueous solutions of salts. Then, the modified Cp powder was prepared into particles as adsorbents. Then, the adsorbents were used for nitrogen\/methane separation in pressure swing adsorption (PSA) at the same condition of 0.2 MPa and 298 K. Research results indicated that there were micropores and lots of mesopores in the Cp, and the pores were mainly slit holes formed by sheet stacking. The adsorbents of NH4-Cp, Cs-Cp, and Cu-Cp showed good equilibrium selectivity for CH4, and the equilibrium separation factors of CH4 and N2 were 2.56, 2.31, and 1.95, respectively. The adsorbents of Na-Cp and Ag-Cp showed good equilibrium selectivity for N2, and the equilibrium separation factors of N2 and CH4 were 7.25 and 6.53, respectively. Consequently, the adsorbent of Na-Cp was suitable for nitrogen\/methane mixture separation, which could make the concentration of methane concentrated from 19.7% to 30.72%.<\/jats:p>","DOI":"10.3390\/ma11102024","type":"journal-article","created":{"date-parts":[[2018,10,18]],"date-time":"2018-10-18T10:55:41Z","timestamp":1539860141000},"page":"2024","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Adsorption Properties of Modified Clinoptilolite for Methane and Nitrogen"],"prefix":"10.3390","volume":"11","author":[{"given":"Xiaofei","family":"Hao","sequence":"first","affiliation":[{"name":"Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China"},{"name":"Zhengzhou Fulong Science and Technology of New materials Co., Ltd., Zhengzhou Institute of Multipurpose Utilization of Mineral Resourse, China Academy of Geological Sciences, Zhengzhou 450006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongjie","family":"Hu","sequence":"additional","affiliation":[{"name":"Zhengzhou Fulong Science and Technology of New materials Co., Ltd., Zhengzhou Institute of Multipurpose Utilization of Mineral Resourse, China Academy of Geological Sciences, Zhengzhou 450006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhen","family":"Li","sequence":"additional","affiliation":[{"name":"Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Limei","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Shenyang Jianzhu University, Shenyang 110168, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1614-9980","authenticated-orcid":false,"given":"Xueqin","family":"Liu","sequence":"additional","affiliation":[{"name":"Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yinnian","family":"Zhang","sequence":"additional","affiliation":[{"name":"Zhengzhou Fulong Science and Technology of New materials Co., Ltd., Zhengzhou Institute of Multipurpose Utilization of Mineral Resourse, China Academy of Geological Sciences, Zhengzhou 450006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"474","DOI":"10.1205\/026387603765173736","article-title":"Methane separation from coal mine methane gas by vacuum pressure swing adsorption","volume":"81","author":"Olajossy","year":"2003","journal-title":"Chem. Eng. Res. Des."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2648","DOI":"10.1021\/ef060119e","article-title":"Removal of carbon dioxide from natural gas vacuum pressure swing adsorption","volume":"20","author":"Cavenati","year":"2006","journal-title":"Energy Fuels"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/j.seppur.2010.11.004","article-title":"Numerical simulation of a three-bed PSA cycle for the methane\/nitrogen separation with silicatlite","volume":"77","author":"Delgado","year":"2011","journal-title":"Sep. Purif. Technol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1016\/j.cej.2014.05.034","article-title":"Selective adsorption of N2 over CH4 in flexible Sr2+ and Ba2+ UPRM-5 (TEA) titianium silicates: Effect of activation temperature","volume":"252","author":"Yu","year":"2014","journal-title":"Chem. Eng. 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Purif."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/11\/10\/2024\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:26:30Z","timestamp":1760196390000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/11\/10\/2024"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,10,18]]},"references-count":13,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2018,10]]}},"alternative-id":["ma11102024"],"URL":"https:\/\/doi.org\/10.3390\/ma11102024","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,10,18]]}}}