Control of Co0/Co2C dual active sites for higher alcohols synthesis from syngas

Abstract

Dual active sites play a vital role in higher alcohols synthesis (HAS) from syngas and the relative proportion of each active sites may greatly affect the contact boundaries between the dual active sites and the reaction network. Herein, we regulated the ratio of Co0/Co2C dual active sites by changing the content of Na promoter, and investigated the structure-performance relationship of Co0/Co2C for HAS. It was found that both of the catalytic activity and paraffins selectivity increased with the increase of Co0/Co2C ratio, while the formation of olefins was inhibited. However, the oxygenates selectivity exhibited a volcano variation trend. The results suggested that only when the Co0/Co2C ratio was in the appropriate range, the strong synergistic effect of Co0/Co2C dual-site could be obtained, and the CO insertion rate can thus match well with hydrogenation rate and chain-growth rate, which benefited for the oxygenates formation.