Effect of Cobalt Catalyst Confinement in Carbon Nanotubes Support on Fischer-Tropsch Synthesis Performance

• Main Authors: Pivehzhani, Omid Akbarzadeh, Mohd Zabidi, Noor Asmawati, Wahab, Yasmin Abdul, Hamizi, Nor Aliya, Chowdhury, Zaira Zaman, Merican, Zulkifli Merican Aljunid, Marlinda, Ab Rahman, Akhter, Shamima, Rasouli, Elisa, Johan, Mohd Rafie
• Format: Article
• Published: MDPI 2018
• Subjects: Q Science (General); QD Chemistry
• Online Access: http://eprints.um.edu.my/22611/; https://doi.org/10.3390/sym10110572

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 °C resulted in the formation of defects on the CNTs. Increasing the temperature of the pre-treatment of the CNTs from 600 °C to 900 °C, 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 °C 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 °C has improved the stability and activity of the Co/CNTs catalyst in FTS.