{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T10:09:54Z","timestamp":1775124594382,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2018,11,1]],"date-time":"2018-11-01T00:00:00Z","timestamp":1541030400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education, Malaysia under the Fundamental Research Grant Scheme","award":["FRGS\/1\/2012\/SG01\/UTP\/02\/01"],"award-info":[{"award-number":["FRGS\/1\/2012\/SG01\/UTP\/02\/01"]}]},{"DOI":"10.13039\/501100004386","name":"University of Malaya","doi-asserted-by":"publisher","award":["NANOCAT RU-2017 Grant"],"award-info":[{"award-number":["NANOCAT RU-2017 Grant"]}],"id":[{"id":"10.13039\/501100004386","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Pre-treating the multi-walled carbon nanotubes (CNTs) support by refluxing in 35 vol% nitric acid followed by heating at the temperature of 600 to 900 \u00b0C resulted in the formation of defects on the CNTs. Increasing the temperature of the pre-treatment of the CNTs from 600 \u00b0C to 900 \u00b0C, enhanced the fraction of cobalt-oxide nanoparticles encapsulated in the channels of CNTs from 31% to 70%. The performance of Co\/CNTs in Fischer-Tropsch synthesis (FTS) was evaluated in a fixed-bed micro-reactor at a temperature of 240 \u00b0C and a pressure of 2.0 MPa. The highest CO conversion obtained over Co\/CNTs.A.900 was 59% and it dropped by ~3% after 130 h of time-on-stream. However, maximum CO conversion using Co\/CNTs.A.600 catalysts was 28% and it decreased rapidly by about 54% after 130 h of time-on-stream. These findings show that the combined acid and thermal pre-treatment of CNTs support at 900 \u00b0C has improved the stability and activity of the Co\/CNTs catalyst in FTS.<\/jats:p>","DOI":"10.3390\/sym10110572","type":"journal-article","created":{"date-parts":[[2018,11,1]],"date-time":"2018-11-01T11:31:47Z","timestamp":1541071907000},"page":"572","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["Effect of Cobalt Catalyst Confinement in Carbon Nanotubes Support on Fischer-Tropsch Synthesis Performance"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0904-5593","authenticated-orcid":false,"given":"Omid","family":"Akbarzadeh","sequence":"first","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6145-8643","authenticated-orcid":false,"given":"Noor Asmawati","family":"Mohd Zabidi","sequence":"additional","affiliation":[{"name":"Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"}]},{"given":"Yasmin","family":"Abdul Wahab","sequence":"additional","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Nor Aliya","family":"Hamizi","sequence":"additional","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Zaira Zaman","family":"Chowdhury","sequence":"additional","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3462-8894","authenticated-orcid":false,"given":"Zulkifli","family":"Merican Aljunid Merican","sequence":"additional","affiliation":[{"name":"Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"}]},{"given":"Marlinda","family":"Ab Rahman","sequence":"additional","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Shamima","family":"Akhter","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Elisa","family":"Rasouli","sequence":"additional","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Mohd Rafie","family":"Johan","sequence":"additional","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1016\/S0926-860X(99)00275-6","article-title":"Fischer-Tropsch reactions and the environment","volume":"189","author":"Dry","year":"1999","journal-title":"Appl. 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