Effect of promoter on performance of hydrogen production from steam reforming of dimethyl ether with a metal foam microreactor

The CuO-ZnO-Al2O3/HZSM-5 catalyst prepared by co-precipitation and mechanical mixing with HZSM5 was used for hydrogen production from steam reforming of dimethyl ether.The effects of Cr,Zr,Co and Ce promoters on catalyst performance were investigated by means of X-ray diffraction(XRD),temperature programmed reduction(H2-TPR),SEM and BET.The results showed that addition of promoter Cr can reduce the average pore diameter and reduction temperature of catalyst effectively,and inhibited the form of Zn(OH)2 in the catalyst preparation process.The conversion of dimethyl ether and hydrogen yield reaches 99% and 95% respectively at low reaction temperature.The effects of reaction termperature,space velocity and steam-to-DME ratio were investigated.At the conditions of 250 ℃,the space velocity of 3 884 mL/g.h),H2O/DME=5,over 97% of DME conversion was obtained over the CuO-ZnO-Al2O3-Cr2O3/HZSM-5 catalyst and the catalytic activity has no obvious deactivation during 50 h durability test.