{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T10:09:56Z","timestamp":1775124596805,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,1,4]],"date-time":"2019-01-04T00:00:00Z","timestamp":1546560000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Malaya, Nanotechnology and Catalysis Research Centre","award":["RU011-2017"],"award-info":[{"award-number":["RU011-2017"]}]},{"name":"Universiti Teknologi PETRONAS &amp; Ministry of Education of 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"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Multiwalled carbon nanotubes (CNT) supported cobalt oxide was prepared as a catalyst by strong electrostatic adsorption (SEA) method. The CNT support was initially acid- and thermal-treated in order to functionalize the support to uptake more Co clusters. The Co\/CNT were characterized by a range of analytical methods including transmission electron microscopy (TEM), temperature programmed reduction with hydrogen (H2-TPR), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, atomic absorption spectroscopy (AAS), Zeta sizer particle size analysis and Brunauer\u2013Emmett\u2013Teller (BET) surface area analysis. TEM images showed cobalt particles were highly dispersed and impregnated at both exterior and interior walls of the CNT support with a narrow particle size distribution of 6\u20138 nm. In addition, the performance of the synthesized Co\/CNT catalyst was tested using Fischer\u2013Tropsch synthesis (FTS) reaction which was carried out in a fixed-bed micro-reactor. H2-TPR profiles indicated the lower reduction temperature of 420 \u00b0C was required for the FTS reaction. The study revealed that cobalt is an effective metal for Co\/CNT catalysts at pH 14 and at 900 \u00b0C calcination temperature. Furthermore, FTS reaction results showed that CO conversion and C5+ selectivity were recorded at 58.7% and 83.2% respectively, which were higher than those obtained using a Co\/CNT catalyst which pre-treated at a lower thermal treatment temperature and pH.<\/jats:p>","DOI":"10.3390\/sym11010050","type":"journal-article","created":{"date-parts":[[2019,1,4]],"date-time":"2019-01-04T11:34:26Z","timestamp":1546601666000},"page":"50","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Effect of pH, Acid and Thermal Treatment Conditions on Co\/CNT Catalyst Performance in Fischer\u2013Tropsch Reaction"],"prefix":"10.3390","volume":"11","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"}]},{"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":"Nor Aliya","family":"Hamizi","sequence":"additional","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Yasmin","family":"Abdul Wahab","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 Merican","family":"Aljunid Merican","sequence":"additional","affiliation":[{"name":"Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1543-9887","authenticated-orcid":false,"given":"Wageeh A.","family":"Yehya","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, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Md.","family":"Shalauddin","sequence":"additional","affiliation":[{"name":"Nanotechnology &amp; Catalysis Research Centre, 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":[[2019,1,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8938","DOI":"10.1021\/ie0712434","article-title":"Fischer\u2212Tropsch Synthesis:\u2009 Comparison of Performances of Iron and Cobalt Catalysts","volume":"46","author":"Davis","year":"2007","journal-title":"Ind. 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