{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T11:22:36Z","timestamp":1777288956447,"version":"3.51.4"},"reference-count":70,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2023,11,24]],"date-time":"2023-11-24T00:00:00Z","timestamp":1700784000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Tunisian Ministry of Higher Education and Scientific Research","award":["PID2019\u2013111219RB-100"],"award-info":[{"award-number":["PID2019\u2013111219RB-100"]}]},{"name":"Tunisian Ministry of Higher Education and Scientific Research","award":["PID 2022-143180OB-I00"],"award-info":[{"award-number":["PID 2022-143180OB-I00"]}]},{"name":"Tunisian Ministry of Higher Education and Scientific Research","award":["PRE2020-094027"],"award-info":[{"award-number":["PRE2020-094027"]}]},{"name":"Tunisian Ministry of Higher Education and Scientific Research","award":["BES-2017-080240"],"award-info":[{"award-number":["BES-2017-080240"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PID2019\u2013111219RB-100"],"award-info":[{"award-number":["PID2019\u2013111219RB-100"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PID 2022-143180OB-I00"],"award-info":[{"award-number":["PID 2022-143180OB-I00"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PRE2020-094027"],"award-info":[{"award-number":["PRE2020-094027"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["BES-2017-080240"],"award-info":[{"award-number":["BES-2017-080240"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PID2019\u2013111219RB-100"],"award-info":[{"award-number":["PID2019\u2013111219RB-100"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PID 2022-143180OB-I00"],"award-info":[{"award-number":["PID 2022-143180OB-I00"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PRE2020-094027"],"award-info":[{"award-number":["PRE2020-094027"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["BES-2017-080240"],"award-info":[{"award-number":["BES-2017-080240"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This work is dedicated to the study of the effect of the synthesis conditions (drying and calcination) of sulfated zirconia on the final catalytic behavior of bifunctional composite catalysts prepared by the physical mixing of the sulfated zirconia (methanol dehydration catalyst) with Cu\/ZnO\/Al2O3 (CZA; methanol synthesis catalyst). The main objective was to optimize the CZA-ZrO2\/SO42\u2212 composite catalyst for its use in the direct production of dimethyl ether (DME) from syngas. Sulfated zirconia aerogel (AZS) and xerogel (XZS) were prepared using the sol\u2013gel method using different solvent evacuation conditions and calcination temperatures, while the Cu-ZnO(Al) catalyst was synthesized using the coprecipitation procedure. The effectivity of CZA-ZrO2\/SO42\u2212 composite catalysts for the direct production of dimethyl ether (DME) from syngas was evaluated in a flow reactor at 250 \u00b0C and 30 bar total pressure. The characterization of the sulfated zirconia aerogels and xerogels using different techniques showed that the mesoporous aerogel (AZS0.5300) exhibited the best textural and acidic properties due to the gel drying under supercritical conditions and calcination at 300 \u00b0C. As a result, the composite catalyst CZA-AZS0.5300 exhibited seven times higher DME production than its xerogel-containing counterpart (364 vs. 52 \u03bcmolDME\u00b7min\u22121\u00b7gcat\u22121). This was attributed to its well-matched metal surface, mesoporous structure, optimal crystallite size and, most importantly, its higher acidity.<\/jats:p>","DOI":"10.3390\/ma16237328","type":"journal-article","created":{"date-parts":[[2023,11,24]],"date-time":"2023-11-24T10:10:39Z","timestamp":1700820639000},"page":"7328","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Improved Dimethyl Ether Production from Syngas over Aerogel Sulfated Zirconia and Cu-ZnO(Al) Bifunctional Composite Catalysts"],"prefix":"10.3390","volume":"16","author":[{"given":"Hela","family":"Lassoued","sequence":"first","affiliation":[{"name":"Laboratory of Material Chemistry and Catalysis, Department of Chemistry, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis 2092, Tunisia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Noelia","family":"Mota","sequence":"additional","affiliation":[{"name":"Instituto de Cat\u00e1lisis y Petroleoqu\u00edmica (CSIC), c\/Marie Curie 2, Cantoblanco, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0259-9825","authenticated-orcid":false,"given":"Elena","family":"Mill\u00e1n Ord\u00f3\u00f1ez","sequence":"additional","affiliation":[{"name":"Instituto de Cat\u00e1lisis y Petroleoqu\u00edmica (CSIC), c\/Marie Curie 2, Cantoblanco, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0710-3577","authenticated-orcid":false,"given":"Sahar","family":"Raissi","sequence":"additional","affiliation":[{"name":"Laboratory of Material Chemistry and Catalysis, Department of Chemistry, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis 2092, Tunisia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohamed Kadri","family":"Younes","sequence":"additional","affiliation":[{"name":"Laboratory of Material Chemistry and Catalysis, Department of Chemistry, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis 2092, Tunisia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carlos","family":"Quilis Romero","sequence":"additional","affiliation":[{"name":"Instituto de Cat\u00e1lisis y Petroleoqu\u00edmica (CSIC), c\/Marie Curie 2, Cantoblanco, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rufino M.","family":"Navarro Yerga","sequence":"additional","affiliation":[{"name":"Instituto de Cat\u00e1lisis y Petroleoqu\u00edmica (CSIC), c\/Marie Curie 2, Cantoblanco, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1016\/j.fuproc.2013.10.018","article-title":"Emissions from DME combustion in diesel engines and their implications on meeting future emission norms: A review","volume":"119","author":"Thomas","year":"2014","journal-title":"Fuel Process. 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