A study on the mechanical strength of Fe2O3/Cr2O3/CuO catalyst for high temperature water gas shift reaction

Abstract

The present study aims to investigate the effects of iron (hydr)oxide phases formed during precipitation and the addition of different binders on the mechanical and catalytic performance of the catalyst. A series of Fe2O3/Cr2O3/CuO catalysts were synthesized via the oxidation-precipitation method. MgCO3, aluminous cement, calcium magnesium aluminate cement and a casting repair paste (CRP) were used as the binder. XRD, SEM, BET, BJH, and TPR analyses were performed to characterize the prepared samples. Also, the Weibull model was used to analyze the crushing strength data of the fresh and used catalysts. The results show that the synthesis of the catalyst by oxidation of Fe2+ ions in low pH media could modify the mechanical strength of the catalyst. Also, it was found that the addition of binder affects the crystallinity, reducibility and activity of the HTS catalysts, as well as the mechanical strength. Among the fresh catalysts, the sample prepared by MgCO3 showed the best mechanical behavior. In comparison, binder CRP exhibited the highest crush strength after reduction and reaction processes and the slightest side effects on the structure and performance of the catalyst. The activity loss during the reaction was found to be significant for the cement binders.