The catalytic cracking of palm oil to fuels was studied in a fixed bed microreactor operated at atmospheric pressure, a reaction temperature of 350−450 °C and weight hourly space velocities (WHSVs) of 1−4 h-1. HZSM-5, zeolite β, and ultrastable Y (USY) zeolites with different pore sizes were used to study the effects of reaction temperature and WHSV on the conversion of palm oil and yields of gasoline. The performances of HZSM-5−USY and HZSM-5−zeolite β hybrid catalysts containing 10, 20, and 30 wt % HZSM-5 were investegated. Potassium-impregnated K−HZSM-5 catalysts with different potassium loadings were used to study the effect of acidity on the selectivity for gasoline formation. The major products obtained were organic liquid product (OLP), hydrocarbon gases, and water. HZSM-5 catalyst gave conversion of 99 wt % and a gasoline yield of 28 wt % at a reaction temperature of 350 °C and WHSV of 1 h-1 and was the best among the three zeolites tested. The HZSM-5−USY hybrid catalyst performed better than USY catalyst as it resulted in a higher gasoline yield, whereas HZSM-5−zeolite β hybrid catalyst gave lower conversion compared to that of zeolite β. The selectivity for gasoline decreased from 45 to 10 wt % with an increase in potassium concentration from 0 to 1.5 wt %.

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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.

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