Hydrogen production from steam reforming of methanol over Cu-based catalysts: The behavior of ZnxLaxAl1-xO4 and ZnO/La2O3/Al2O3 lined on cordierite monolith reactors

Abstract

The effect of ceramic support on the performance of methanol reforming process catalysts was studied by synthesizing Cu/Zn1.11La1.26Al0.5O4.27 and comparing it with optimized, conventional γAl2O3 based catalyst in a monolithic reactor. The physicochemical properties of the synthetic catalysts were studied using BET, FESEM, FTIR, XRD, TGA, TPR, TEM and XPS analyses for better evaluation of their catalytic performance. The results showed that the sponge like ceramic support Cu/Zn1.11La1.26Al0.5O4.27 catalyst is very highly efficient and active, has a lower reduction temperature and possess better pore size and pore volume compared with γ-Al2O3 based catalysts. Comparison of Cu/γAl2O3, Cu/La-γAl2O3, Cu-Zn/La-γAl2O3 and Cu-Zn/γAl2O3 catalysts shows that the presence of Zn undesirably affects methanol conversion at higher temperatures while positively affecting the conversion at lower temperatures. Unlike Zn, La functions better at higher temperatures with respect to conversion and selectivity to H2. Therefore, Cu-Zn/La-γAl2O3 catalyst function better works uniformly at all temperatures. The conversion and selectivity to H2 of the new Cu/Zn1.11La1.26Al0.5O4.27 catalyst (97% and 91% respectively) are greater than the alumina supported catalysts such as Cu-Zn/La-γAl2O3 (90% and 73% respectively). The obtained results show that in this process, the designed Monolith/Zn1.11La1.26Al0.5O4.27 structure has a remarkable impact on methanol conversion and carbon monoxide selectivity.