Study on catalytic hydrogenation of carbon dioxide to dimethyl ether

A bifunctional catalyst for one step synthesis of methanol and dimethyl ether via carbon dioxide hydrogenation was prepared from CNJ202 methanol synthesis catalyst and HZSM 5. Experimental results showed that the appropriate HZSM-5/CNJ202 ratio is 0.5(wt/wt); optimum calcination temperatureis 550℃; recommended reduction condition for the catalyst is at atmospheric pressure, 250℃, in N 2 stream containing 2%H 2 for 6h. Particle size of the bifunctional catalyst and GHSV has no evident effect on its selectivity to dimethyl ether ,but higher temperature favours selectivity to dimethyl ether. It was shown that further improvement on the bifunctional catalyst may greatly enhance CO 2 conversion to meet the requirement of commercial production.