Improvement on Coke Formation of CaO-Ni/Al2O3 Catalysts in Ethylene Production via Dehydration of Ethanol

Carbon deposition during ethanol dehydration remains an issue that needs a conceivable solution as ethylene is coke-precursor for acidic-type catalysts. This research is focused on bimetallic CaO-Ni/Al2O3 catalyst to increase the resistance of coke formation on catalyst which mainly due to decomposition of carbon. Using wet impregnation procedure, various metal loadings of CaO and Ni (2-10wt%) were introduced onto γ-alumina support. The prepared catalysts then were subjected to in-situ activation in a fixed-bed reactor using H2/N2 gas mixture before underwent the ethanol dehydration process in the same reactor. Catalysts were characterized using TEM, FTIR and FESEM. While CHNS Elemental Analyzer was used to observe coke formation before and after reaction. Based on the results obtained, the catalyst composition 6wt%CaO-10wt%Ni/Al2O3 shows the best conversion of ethylene (87.89%) at 450oC of reaction temperature. It also suppressed the carbon formation only 13.28% carbon content after the reaction.