Synthesis and characterization of Cr-Co/γ-alumina catalyst for ethanol dehydration

Primary alcohol dehydration reaction catalysis by using γ-Al2O3 catalyst can produce ether compounds and alkenes. The combination chrome-cobalt and alumina catalyst could convert ethanol to diethyl ether in the ethanol dehydration process. The purpose of this study was to determine the performance of Cr-Co with the support of γ-Al2O3 catalyst for ethanol dehydration to diethyl ether. Cr-Co/γ-Al2O3 catalyst was prepared using incipient wetness impregnation. γ-Al2O3 catalyst was impregnated with chrome and cobalt metals at various metal loading 5 and 10% and impregnated ratio of Cr-Co (1:1; 1:2; and 2:1). The samples were calcined at 550°C for 3 hours in nitrogen and then reduced continuously by hydrogen at 600°C for 5 hours. Then catalyst was analyzed for characterization using BET, XRD, and SEM-EDX. Treatment of γ-Al2O3 in various ratio of chrome and cobalt impregnation decreased the total surface area. Increasing metal loading in Cr-Co impregnation on γ-Al2O3 decreased total surface area and increased average pore diameter. Impregnation process lowered the crystallinity but still maintained the material crystal structure. The reduced surface area of the catalyst does not mean the effectiveness of the catalyst is reduced, but the metal will actually increase the active site of the catalyst and will affect the rate of reaction in the catalyst.