Effect of calcination/reduction temperature of Ni impregnated CeO2–ZrO2 catalysts on hydrogen yield and coke minimization in low temperature reforming of ethanol

Abstract

CeO2–ZrO2 was proven to be a quite effective catalyst support for steam reforming of ethanol (SRE). In this study, properties of Ni impregnated mesoporous CeO2–ZrO2 catalysts of different compositions were optimized by changing the calcination/reduction temperature. Increase of calcination/reduction temperature from 400 °C to 650 °C caused significant decrease in surface area and redox ability of the catalysts, yielding higher coke formation and lower hydrogen yields. Results proved that, very high hydrogen selectivity values with negligible coke formation can be achieved at a SRE reaction temperature of 450 °C, over the Ni impregnated ceria zirconia mixed oxide catalyst, which was also calcined/reduced at 450 °C. Considering its high hydrogen selectivity values with negligible coke formation, the catalyst containing a CeO2/ZrO2 ratio of 6:1 was found as the best catalyst for low temperature SRE. Achievement of high hydrogen yields with negligible coke formation at SRE temperatures as low as 400 °C was quite promising from the point of view of hydrogen economy.