The activity of the CoSiO2 catalyst in relation to pretreatment Original Research Article

The activity and characteristics of the nitrate derived CoSiO2 were determined in relation to reductive pretreatment. With increasing reduction temperature (300–450°C), the extent of reduction increased. This increase was not, however, accompanied with increased chemisorption capacity. Namely, the hydrogen chemisorption was highest at a reduction temperature of approx. 300°C. Also, the carbon monoxide adsorption was almost constant at 200–400°C, and decreased drastically thereafter. Thus, the results suggest that cobalt agglomerated at temperatures above 400°C. The activity in toluene hydrogenation correlated well with the hydrogen uptake for reduction temperatures of above 300°C. Also, the CO hydrogenation activity of the catalyst decreased with increasing temperature of reduction (400–450°C) due to the decrease in the number of active sites.