Investigating the effects of synthesis parameter on textural and catalytic properties of ZnO–CuO–Al2O3–Cr2O3 mixed oxide in water gas shift reaction

Abstract

The present study has investigated the influence of preparing conditions, including aging temperature and time, pH, and Tcalcination, on the co-precipitated ZnO–CuO–Al2O3–Cr2O3 mixed oxide at a high-temperature water gas shift reaction. XRD, BET, FTIR, TG-DTA, SEM, TEM, and H2-TPR were used to characterize the relationships between the synthesis parameters and the physicochemical features. The investigation proved that the activity in aging 5 h could be related to higher pore volume and lower crystalline size of 0.24 cm3g-1 and 6.4 nm, respectively. Also found that increasing the aging temperature to 60 °C results in a rise in the surface area and particle size of less than 6 nm, enhancing the catalyst activity. The findings showed that raising the Tcalcination reduced the surface area from 132 to 65 m2 g−1. It has been concluded that the CO conversion of 70 % was obtained when aged at 60 °C and calcination temperature of 400 °C.