Preparation and activity of Cu/ZnO-CNTs nano-catalyst on steam reforming of methanol

A novel Cu/ZnO-CNTs (carbon nano-tubes) nano-catalyst was prepared by a chemical reduction and wet impregnation method, and was applied to catalyze the steam reforming reaction of methanol. If one uses CNT as the support, the CNTs should be pre-treated by nitric acid and sulfuric acid at 60 °C for 24 h to create defects on its surface; the hydrophilicity of CNTs was improved by adding a suitable amount of ethanol. The catalysts were characterized by TEM, XRD, FTIR and TGA. A good dispersion of Cu nano-particles on the surface of CNTs with particle size about 10 nm is identified by TEM analysis. Using 23 wt% Cu80ZnO20-CNTs as the catalyst, we obtained the hydrogen yield for steam reforming of methanol of 83% at 280 °C and near 100% at temperatures higher than 320 °C with 1.5 of molar ratio of water to methanol. The higher hydrogen production (larger than 400mmol/(s kg cat)), higher selectivity of CO2 and lower CO concentration were also observed.

Graphical abstractA novel Cu/ZnO-CNTs (carbon nano-tubes) nano-catalyst was prepared by chemical reduction and wet impregnation method, and was applied to catalyze the steam reforming reaction of methanol.CH3OH + H2O ⇌ CO2 + 3H2XRD analysis of 23 wt% Cu/ZnO-CNTs catalysts; (▾) CNT, (▿) CuO, (♦) ZnO, (●) Cu. Figure optionsDownload full-size imageDownload as PowerPoint slide