Insight into the methanol steam reforming behavior of Cu-containing spinels CuB2O4 (B Co, Al, Mn, La, Cr)

Co-precipitation method was applied to prepare five Cu-containing spinels CuB2O4 with different B-sites (CuCo2O4, CuAl2O4, CuMn2O4, CuLa2O4, CuCr2O4) and the physicochemical properties of the spinels were characterized comprehensively. The Cu-containing spinels were then washcoated on Cu foams to fabricate monolithic catalysts and the catalytic performance of the catalysts under different reaction conditions was investigated in a methanol steam reforming microreactor. The effects of B-site on the structure-activity relationship and sustained release catalysis were discussed in detail. Results showed that the CuCo2O4 spinel with small particles, excellent reducibility, low acidity, large specific surface area and superior surface chemical state led to the best performance of the monolithic catalyst loaded with CuCo2O4. The B-site resulted in completely different characteristics of spinels, leading to diverse sustained release properties during the catalysis. Owing to the sustained release behavior, the catalytic stability of the Cu-containing spinel was significantly improved compared with the conventional Cu-based catalyst.