Kinetics of Fischer-Tropsch synthesis on titania-supported cobalt

Rate data have been obtained for CO hydrogenation on a well-characterized 1 1.7% Co/TiO2 catalyst in a differential fixed bed reactor at 20 atm, 180-24 0 degrees C, and 5% conversion over a range of reactant partial pressures. The resulting kinetic parameters can be used to model precisely and accurat ely the kinetics of this reaction within this range of conditions. Turnover frequencies and rate constants determined from this study are in very good to excellent agreement with those obtained in previous studies of other co balt catalysts, when the data are normalized to the same conditions of temp erature and partial pressures of the reactants. Based on this comparison CO conversion and the partial pressure of product water apparently have littl e effect on specific rate per catalytic site. The data of this study are fi tted fairly well by a simple power law expression of the form -r(CO) = kp(H 2)(0.74)P(CO)(-0.24), where k=5.1x 10(-3) s(-1) at 200 degrees C, P=10 atm, and H-2/CO=2/1; however, they are best fitted by a simple Langmuir-Hinshel wood (LH) rate form -r(CO) = aP(H2)(0.74) P-CO/(1 + bP(CO))(2) similar to t hat proposed by Yates and Satterfield. (C) 2000 Elsevier Science B.V. All r ights reserved.