Promotion of lanthanum-supported cobalt-based catalysts for the Fischer-Tropsch reaction

This paper focuses on the effect of the La/Co ratio on the structure of alumina cobalt supported catalysts for Fischer-Tropsch synthesis. Catalysts are prepared by wetness impregnation of alumina followed by calcination in air. The catalysts contain 10 wt% of cobalt and between 0 and 20 wt% of La (0, 5, 10, 15, 20). The catalysts were activated by reduction in hydrogen at 673 K and the catalytic performance was evaluated in a fixed bed reactor at 20 bar and 493 K. A wide range of techniques (BET, XRD, TPR, and XPS) were used for catalyst characterization at each preparation step and showed strong impact of the La/Co ratio on the structure, reducibility of supported cobalt phases. It was shown that 10 wt% of lanthanum allows reducing cobalt aluminate and improving catalytic performances. (C) 2016 Academie des sciences. Published by Elsevier Masson SAS.