A preliminary evaluation of ZSM-5/SBA-15 composite supported Co catalysts for Fischer–Tropsch synthesis

Abstract

a b s t r a c t a r t i c l e i n f oA series of ZSM-5/SBA-15 composite supported Co catalysts were prepared and evaluated for the Fischer-Tropsch synthesis (FTS) aimed to maximise the selectivity of C 5 -C 22 hydrocarbons in the product. The composite support was prepared by physically mixing ZSM-5 and SBA-15 of varying proportions and the finished catalysts had a constant Co loading of 15wt.%. The catalysts were tested for their performance in a high pressure fixed-bed reactor operating at T = 240°C, P = 2.0 MPa, H 2 /CO = 2 and GHSV = 1000 h −1. The composite supported catalysts were shown to have much improved catalytic performance over the respective single material supported catalysts. The catalyst with 20wt.% ZSM-5 in the composite support gave the maximum CO conversion (90.6%), maximum selectivity of C 5 -C 22 hydrocarbons (70.0%) and minimum selectivity of light hydrocarbons (13.3% for CH 4 and 7.0% for C 2 -C 4 alkanes). The catalysts were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy with an energy dispersive X-ray spectrometer, temperature programmed desorption and temperature programmed reduction. It was revealed that the superior catalytic performance can be attributed to the large pore size and high dispersion of Co 3 O 4 , which afforded an optimum reducibility and acid site density.

RETRACTED: The Influence of Texture on Co/SBA–15 Catalyst Performance for Fischer–Tropsch Synthesis

“…[17,18]. García et al explored the effects of the Co-SiO2 interaction, and thought that SBA could suppress the aggregation of metal particles and promote the metal dispersion [19]. In this paper, the effect of the texture of Co/SBA-15 on FTS performance was investigated.…”

“…Cai et al and Wang et al reported that the CO conversion was 6.51%-20.51%, and C 5+ selectivity was 42.43%-77.14% when Ru promoted Co/SBA-15 catalysts was used in FTS [17,18]. García et al explored the effects of the Co-SiO 2 interaction, and thought that SBA could suppress the aggregation of metal particles and promote the metal dispersion [19].In this paper, the effect of the texture of Co/SBA-15 on FTS performance was investigated. Moreover, the reaction temperature and Co loading were also discussed.…”

Effects of titanium silicalite and TiO2 nanocomposites on supported Co‐based catalysts for Fischer–Tropsch synthesis

“…But with the addition of TiO 2 , the pore volume shows a ‘volcano’ type of trend with highest point for TS–TiO 2 ‐0.1, the same trend also being found in previous research . The reason may be attributed to the formation of new pores in the process of support accumulation . Similar to the corresponding supports, the Co‐loaded catalysts show the same changing tendency in pore volume.…”

“…The reason may be the TiO 2 additive with lower surface area and larger pore diameter. But with the addition of TiO 2 , the pore volume shows a ‘volcano’ type of trend with highest point for TS–TiO 2 ‐0.1, the same trend also being found in previous research . The reason may be attributed to the formation of new pores in the process of support accumulation .…”

Fischer–Tropsch Synthesis Bifunctional Catalysts: Cobalt Supported on 3D Mesoporous Cellular Silica Foams Assembled by Using ZSM‐5 Seeds

“…Microporous zeolites with long‐path micropores have strong acidity, although they cause over‐cracking of hydrocarbons and give high selectivity to methane owing to the slow transportation of products to/from acidic sites . Furthermore, strong interactions between cobalt and pure zeolites usually cause low CO conversions . A recent study has attempted to synthesize large pore Co/zeolite bifunctional catalysts for FTS, such as mesopore/macropore zeolites .…”