TH2685A - Process for preparing hydrocarbons - Google Patents

Abstract

Syngas with an H2/CO molar ratio between 0.25 and 1.0 is converted into hydrocarbons by exposure to a mixture of a special cobalt-containing Fischer-Tropsch catalyst and a CO-Shift catalyst containing Cu and Zn. Both catalysts are present in amounts that satisfy the following relationship (chemical formula): M is the atomic ratio of (Cu + Zn)/Co in the catalyst mixture, and F is the H2/CO molar ratio in the syngas.

Claims (8)

1. The process for preparing hydrocarbons by catalytic reaction of carbon monoxide with hydrogen is characterized as follows: a feedstock containing H2 and CO with a molar ratio of H2/CO(F) in the range of 0.25 and 1.0 is exposed to a mixture of two catalysts at high temperature and pressure. One catalyst is composed of 3–60 p.m. of cobalt and at least one other metal selected from a group consisting of zirconium, titanium, and chromium in amounts of 0.1–100 p.m. of silica-alumina or silica-alumina in amounts of 100 p.m. of silica and alumina, which has been prepared by kneading and/or saturated diffusion; and the other catalyst is composed of copper and zinc. Containing a Cu/Zn atomic ratio in the range between 0.1 and 10, and that two types of catalysts are present in the catalyst mixture in ratios that satisfy the relationship (chemical formula) where M is the atomic ratio of (Cu+Zn)/CO in the catalyst mixture. 2. The process as claimed in claim 1, which characterizes the cobalt catalyst to follow the relationship (3+4R > L/S > (0.3+0.4R)), where L = total amount of cobalt present on the catalyst, expressed in mg of Co/ml of catalyst; S = surface area of the catalyst, expressed in m²/ml of catalyst; and R = weight ratio of the amount of cobalt adhering to the support by kneading to the total amount of cobalt present on the catalyst. 3. The process as claimed in claim 1 or 2, which shows that to 100 parts by weight of the support, the cobalt catalyst will consist of 15-50 parts by weight of cobalt and 0.1-5 parts by weight of another metal, if during preparation the cobalt is deposited first and the other metal is deposited next, or vice versa. 4. The process, as enshrined in one of the claims of Claims 1-3, exhibits the characteristic that the cobalt catalyst has zirconium as a secondary metal and silica as a supporting material. 5. A process that provides for one of the claims in claims 1-4 that characterizes a copper-zinc-containing compound with a Cu/Zn atomic ratio in the range between 0.25 and 4. 6. The process is entitled under one of the claims in Claims 1-5, which describe the characteristics of a process performed at temperatures of 125-350°C and pressures of 5-100 bar. 7. The process is as claimed in claim 6, which describes the characteristics of a process performed at a temperature of 175-275°C and a pressure of 10-75 bar. 8. The process described in one of the claims of Claims 1-7, which characterizes the preparation of a central distillate from the products obtained on a catalyst mixture, where at least the fraction with an initial boiling point higher than the final boiling point of the heaviest central distillate to be the final product is hydrocracking by contact with a catalyst containing one or more noble metals of Group VIII supported on a support at high temperature and pressure.