Catalytic Activity of Electroexplosive Cobalt Nanopowder in Hydrocarbon Synthesis by the Fischer–Tropsch Method

The study aims to develop a method for obtaining a high-performance catalyst for the synthesis of liquid hydrocarbons using the Fischer–Tropsch method based on ultradisperse cobalt powders obtained by the electric explosion method. To determine the catalytic activity of the obtained catalyst samples, the main process parameters, like temperature in the catalyst bed, the process pressure, the feedstock space velocity, and the ratio of reagents in the synthesis gas, were varied. It has been established that highly dispersed cobalt powder obtained by the electrical explosion method is a fairly active catalyst for the synthesis of liquid hydrocarbons via the Fischer–Tropsch process. It has been established that the overall CO conversion rate in the temperature range from 230 to 330 °C ranges from 25 to 90%. However, the formation of the main byproduct of the synthesis, carbon dioxide, is not observed below 270 °C. It was determined that for the developed catalyst sample, the optimal temperature range is from 230 to 260 °C, in which the yield of by-products of synthesis and gaseous hydrocarbons is quite low—the selectivity for methane does not exceed 20%, with the proportion of C5+ hydrocarbons in the liquid phase at the level of 80%. The CO conversion rate increases proportionally with growing pressure. It has been established that cobalt nanopowder exhibits high catalytic activity in reactions of liquid hydrocarbon formation with low hydrogen content in the initial synthesis gas. This fact allows us to conclude that it has potential for use in processing gases obtained during the pyrolysis of biomass or other non-traditional sources of synthesis gas, characterized by an H2:CO ratio of 1:1 to 1.25:1. Catalysts obtained from ultradisperse cobalt powders were shown to be resistant to rapid deactivation under synthesis conditions at operating temperatures for 30 h. During long-term testing, CO conversion remained at 23.5% at 230 °C for the entire duration of the experiment.