Effect of the Reduction Temperature of Co-La-Zr/AC on the Synthesis of Higher Alcohols from Syngas

CO hydrogenation over a Co-La-Zr/AC catalyst prepared by co-impregnation and reduced at different temperatures was studied. The catalyst reduced at 703 K showed good activity at 3.0 MPa, 495 K, H-2-/CO(V/V) = 2, and GHSV = 500 h(-1). CO conversion and selectivity for total alcohols were 59.1% and 42.0%, respectively, and C-6-C-18 higher alcohols were 50.4% of the alcohols. Metallic cobalt and cobalt carbide were detected by XRD as the main cobalt species. The reduction temperature affects both the cobalt dispersion and formation of cobalt carbide. Cobalt carbide may play an important role in the synthesis of higher alcohols on Co-La-Zr/AC.