Cu/ZrO2 Catalyst for Low-Temperature Water-Gas Shift Reaction: Preparation, Characterization and Performance

A series of Cu/ZrO2 catalyst samples with excellent catalytic performance for low-temperature water-gas shift (WGS) reaction were prepared by a two-step method. First, pure monoclinic ZrO2 support was prepared by hydrothermal synthesis, and then a certain amount of CuO was deposited on the support by deposition-precipitation. The catalyst samples were characterized by X-ray diffraction, N-2-physisorption, H-2 temperature-programmed reduction, X-ray fluorescence elemental analysis, high resolution transmission electron microscopy, and scanning electron microscopy, aiming to know the effect of preparation parameters on the catalytic performance of these samples. The relationship between their catalytic performance and structures was discussed. The crystalline size and dispersity of the Cu particles, texture of Cu/ZrO2 catalyst samples as well as the interaction between ZrO2 and Cu are greatly influenced by the preparation conditions, such as the CuO amount, precipitation temperature, precipitant and calcination temperature. And the optimal preparation parameters are ZrO2 loaded with 25% CuO, precipitation at 65 degrees C with KOH as precipitant, and calcination at 300 degrees C for 2 h purging with H-2.