Fischer-Tropsch synthesis over alumina-supported cobalt catalysts: effects of different spray temperature of aluminum slurry

Aluminum slurry was obtained by precipitating Al(NO3)(3)center dot 9H(2)O and ammonium carbonate, and the slurry was dried by adopting spray means. The effects of different spray temperature on the as-synthesised aluminum precursors, calcined alumina, and the supported cobalt catalysts were investigated by the characterizations of SEM, XRD, TG-DTA, H-2-TPD, H-2-TPR, etc., and the activity and stability of the as-prepared catalysts for Fischer-Tropsch synthesis were also studied. It indicated that the aluminum precursor spray dried at 250 degrees C exhibited homogeneous microspheres, the calcined alumina exhibited single-particle size distribution and monomodal pore distribution, and the corresponding supported cobalt catalyst possessed proper cobalt particles (6.4 nm), which was benefitial for acquiring a high conversion rate (the turnover frequency is 17.2 x 10(-3)/s) and excellent stability (the deactivation rate is 0.31%) for Fischer-Tropsch synthesis.