Effect of particle size on carbon monoxide hydrogenation activity of silica supported cobalt catalysts

Abstract

Two series of silica supported cobalt catalysts were prepared by incipient wetness impregnation, one by varying the calcination temperature (200-400{degree}C, 3 wt % Co) and the other by changing the cobalt loading (1-10 wt % Co). Examination by ESCA, XRD, and H{sub 2} chemisorption showed that Co{sub 3}O{sub 4} is the dominant phase. The cobalt phase is reduced to cobalt metal at 400{degree}C. The cobalt particle sizes obtained from ESCA correlated well with those derived from H{sub 2} chemisorption and XRD line broadening. The turnover frequency of Co/SiO{sub 2} for CO hydrogenation was invariant with cobalt dispersion in the range of 6-20% dispersion.