Performance of Pd/Al2O3 catalyst prepared by the deposition of triphenyl phosphine ligand onto catalyst in high pressure acetylene selective hydrogenation
1Sharif University of Technology
2Catalyst Senior Researcher
Selective hydrogenation of acetylene, by using proper catalyst, is an important industrial process with the aim of removing the traces of acetylene in the ethylene rich flow. In this research, palladium catalyst was synthesized over alumina support, exposed to triphenyl phosphine as a ligand, and applied for high pressure tail-end selective hydrogenation of acetylene in an ethylene-rich stream. Catalysts were prepared by impregnation method with different ligand contents (several PPh3 : Pd ratio including 0.02, 1 and 2.5). Their results were compared to non-refined catalyst which showed that the modified catalyst with triphenyl phosphine ligand resulted in higher acetylene conversion (more than 99%) and the extent of over-hydrogenation of ethylene to ethane was lower which means improved selectivity. This catalyst was able to maintain its activity after 22 hours, which is crucial in producing industrial catalysts. Moreover coke deposition was analyzed by fourier transform infrared spectroscopy (FTIR) and showed that increasing the ligand content, could cause decrease in coke deposition.