Effect of citric acid content on the hydrothermal synthesis of CuO/Ce_0.8Zr_0.2O₂ catalytic water gas shift hydrogen production performance

Ce_0.8Zr_0.2O₂ solid solutions were synthesized by hydrothermal method, and active components were loaded by impregnation method to get CuO/Ce_0.8Zr_0.2O₂ catalysts. Effects of citric acid content on the structure, properties and hydrogen production performance of CuO/Ce_0.8Zr_0.2O₂ catalysts were investigated. CuO/Ce_0.8Zr_0.2O₂ catalysts prepared with different citric acid content are distinct in Cu surface area, reduction performance and interaction between Ce_0.8Zr_0.2O₂ solid solution and CuO. Among them, the catalyst prepared with a citric acid concentration of 0.04 mol/L has a large Cu surface area, a low CuO reduction temperature and a strong interaction between Ce_0.8Zr_0.2O₂ solid solution and CuO, which has the best catalytic activity and the highest CO conversion in the water gas shift conversion process. At 320 ℃, water/gas molar ratio n(H₂O)/n(CO) = 2, total volume velocity GHSV = 6600 h⁻¹, its CO conversion is 96.9% close to thermodynamic equilibrium value.