A Ni-Cu-CaO Catalyst for Producing Hydrogen with Very Low CO Concentration By Sorption-Enhanced Steam Reforming of Glycerol

Sorption-enhanced steam reforming of glycerol (SESRG) is attractive for producing high-purity hydrogen and utilizing the by-product of biodiesel. However, the CO concentration in the product gas is usually high (>10000 ppm), which is prohibitive for its direct application for H₂-O₂ fuel cells. It is highly desired to yield high purity of H₂ and simultaneously to minimize the concentration of CO.

In this contribution, we developed a bi-functional catalyst composed of calcium aluminate, calcium oxide and active metal for SESRG. Calcium aluminate (Ca₁₂Al₁₄O₃₃) was designed as a spacer to prevent CaO sintering. High-purity hydrogen, > 96%, and low concentration of CO, ~ 30 ppm, were achieved simultaneously by manipulating the catalytic performance of the bi-functional catalyst during the SESRG reaction through suppressing side reactions, such as methanation and rWGS. The stability has been proved by ten cycle of reaction-desorption experiments, showing the promise to producing high quality H₂.