Effect of Reduction Temperature and Time on Catalytic Performance of 10Ni-6K/CeO2 Catalyst in Medium Temperature Shift Reaction

Abstract

In order to produce purified hydrogen, after natural gas steam reforming, the medium temperature shift (MTS) reaction was carried out using 10Ni-6K/CeO2 catalyst. Catalyst was prepared by simultanious impregnation of Ni and K on ceria support and characterized by XRD and TPR. Reactor tests were done with steam to carbon ratio of 3, GHSV of 12000 h-1 in temperature range of 320-380 °C. effect of reduction temperatures of 300, 400 and 450 °C and reduction times of 1 and 2 h were investigated on CO conversion and CH4 and CO2.selectivities. It was determined that 300 °C is a low temperature for complete reduction and at 450 °C catalyst is sintered and reduction temperature of 400 °C and reduction time of 1 h for nickel promoted by K over cerium oxide has the best catalytic performance (CO conversion of about 90 % with methane selectivity of about 3% at 360 °C).