Hydrogen Production by Ethanol Reforming on Supported Ni-Cu Catalysts.

Abstract

Supported bimetallic Ni–Cu catalysts with different Ni–Cu loadings on alumina (Al2O3), alumina–silica (Al2O3–SiO2), alumina–magnesia (Al2O3–MgO), alumina–zinc oxide (Al2O3–ZnO), and alumina–lanthanum oxide (Al2O3–La2O3) were prepared and tested in ethanol steam reforming for the production of hydrogen (H2). These catalysts were characterized by X-ray diffraction, H2-temperature-programmed reduction, ammonia-temperature-programmed desorption, X-ray photoelectron spectroscopy, thermogravimetry, and differential scanning calorimetry. Cu addition improved the reducibility of NiO. Among the as-prepared catalysts, 30Ni5Cu/Al2O3–MgO and 30Ni5Cu/Al2O3–ZnO demonstrated much higher H2 selectivity and excellent coke resistance compared to the other investigated catalysts. Over 30Ni5Cu/Al2O3–MgO and 30Ni5Cu/Al2O3–ZnO, the respective H2 selectivity was 73.3 and 63.6% at 450 °C and increased to 94.0 and 95.2% at 600 °C. The strong interaction of Ni–Cu and Al2O3–ZnO (or Al2O3–MgO) led to the formation of smaller and highly dispersed CuO and NiO species on the carrier, which is conducive to improved catalytic performance. These Al2O3–MgO- and Al2O3–ZnO-supported bimetallic Ni–Cu materials can be promising catalysts for hydrogen production from ethanol steam reforming.