Synthesis of lower carbon mixed alcohols directly from syngas is one of the most promising approaches for utilizing coal resources cleanly and efficiently. The intrinsic kinetics for this reaction

in which the effects of internal and external diffusion had been excluded

was studied over CoCu/SiO2 catalysts prepared by the impregnation method in a fixed-bed reactor at 503—543 K with molar ratios of H2/CO varying from 4 to 0.5. The apparent activation energies and the reaction orders with respect to H2 and CO for products were calculated through power law models. With the combination of chain growth probability and kinetics

the effect of temperature on reaction mechanism was discussed.