Investigation of the Effect of Cu-Based Catalyst Acidity on Hydrogen Production from the Water-Gas Shift Reaction

The Water Gas Shift reaction is essential to numerous activities, including the production of Hydrogen and the reforming of natural gas. This reaction is enhanced by various catalysts. However, the catalyst acidity is a crucial parameter that affects catalyst performance. In this work, using the co-precipitation method, the effects of catalyst acidity on the low-temperature Water Gas Shift (WGS) reaction were examined. In this way, ternary Cu/ZnO/ZrO2 and Cu/ZnO/Al2O3 catalysts were selected and made. XRD, SEM, BET, NH3-TPD, CO-TPD, and TGA studies were used to characterize the catalysts. The catalytic performance was tested at atmospheric pressure, 180°C, and space velocity 3600 /h, with the inlet gas composition H2O/CO= 1/1 in a fixed bed micro-reactor for around 6 hours. Weak and moderately acidic sites were shown to be preferable to strong sites for the water gas shift reaction. The Cu/ZnO/ZrO2 catalyst was the best one to use in the WGS process because of its acidity, which mostly consisted of mildly acidic sites.  Based on the experimental results, Cu/ZnO/ZrO2 had a hydrogen selectivity and conversion of around 61% and 98%, respectively.