The Effect of Gas Circulation on the High-Pressure Synthesis of Long-Chain С35+ Hydrocarbons from CO and H2

Abstract

The effect of gas recirculation on the production of long-chain C35+ hydrocarbons over supported Co-Al2O3/SiO2 catalyst at a pressure of 6.0 MPa, temperature 225 °C and gas hourly space velocity 1000 h–1 was studied. It was shown that the circulation mode provides isothermicity of the catalyst bed and increases the selectivity to C35+ hydrocarbons and their output. The study revealed that the catalyst deactivation rate decreases by a factor of 8 when the circulation ratio is raised from 2.2 to 6; therewith, the content of unsaturated hydrocarbons in the synthesis products increases twofold.