MO-PROMOTED FE ACTIVATED CARBON CATALYSTS FOR CARBON-MONOXIDE HYDROGENATION

Iron and molybdenum mono- and bimetallic catalysts supported on activated carbon have been prepared using iron pentacarbonyl and molybdenum hexacarbonyl as metal precursors. They have been characterized by temperature programmed reduction (TPR) and carbon monoxide chemisorption at 195 K and 298 K, and their catalytic activity for carbon monoxide hydrogenation at atmospheric pressure was studied under differential conditions, after reduction in hydrogen at several temperatures. Carbon monoxide chemisorption on the monometallic molybdenum catalyst was found to be strongly temperature dependent. On the other hand, the irreversible carbon monoxide chemisorption was largely decreased in the bimetallic catalyst in relation to the monometallic iron sample. The effect of molybdenum on the catalytic activity of FeMo/C is very important, producing an increase in catalytic activity which is very dependent on the reduction temperature. The selectivity of the monometallic iron catalyst is strongly modified by molybdenum addition, which produces a great increase in the yield to methane and a decrease in the alkenes to alkanes (C2 + C3) ratio.