Research On Catalytic Hydrogenation Of Acetophenone By Metal Supported SBA-15

Acetophenone is by-product of many productive technologies, forexample, the effective utilization of C4hydrocarbon. Generated acetophenonegreatly reduced the utilization of raw materials and the economic value ofindustrial production.1-phenethyl alcohol is a kind of aromatic alcohol, whichis important perfume and fine chemical intermediate. The approach ofpreparation1-phenethyl alcohol from acetophenone has great economic valueand social significance, because this approach is most consistent with atomeconomy.SBA-15is mesoporous molecular sieve, which has large surface area,regular pore structure. In recent years, SBA-15has a good prospect inindustrial catalysis. In this paper, with SBA-15as carrier, a series ofmonofuctional catalysts samples and bifunctional SBA-15catalysts sampleswere prepared by the rotary evaporation method. The catalytic performancefor hydrogenation of acetophenone was investigated in a continuous flowmicro reactor. The reaction conditions are T=100℃,P=2.5MPa,LHSV=2.5h-1.The catalysts samples are characterized by XRD, N2adsorption, TEM, H2-TPR as well as activity test for acetophenone hydrogenation reaction. Theloaded metal had a little impact on the structure of SBA-15. However, bothBET surface area and total pore volume of the samples after metal loadingbecome lower to a certain extent.Among monofuctional catalysts samples modified with10wt%metal(Mn, Co, Ni, Cu and Sr), Ni/SBA-15exhibited the best activity,andCo/SBA-15showed the best stability. The activity of the catalysts is in thefollowing order: Ni/SBA-15>> Co/SBA-15> Sr/SBA-15≈Cu/SBA-15>Mn/SBA-15. For15%Ni/SBA-15, the highest conversion of acetophenone is88.91%, and the selectivity of1-phenethyl alcohol can reach82.69%as wellas the yield of1-phenethyl alcohol up to73.51%.Among bifunctional SBA-15catalysts samples modified with5wt%alkaline earth metal (Mg, Ca, Sr), rare earth metal (La, Ce) or transitionmetal (Co, Cu), with acetophenone conversion rate as standard, the activityof the catalysts is in the following order:10%Ni-5%Co/SBA-15>10%Ni-5%Sr/SBA-15>10%Ni-5%Ca/SBA-15>10%Ni-5%La/SBA-15>10%Ni-5%Mg/SBA-15>10%Ni-5%Ce/SBA-15>10%Ni-5%Cu/SBA-15.The catalyst with5%Co exhibited the best activity, over whichacetophenone conversion increased by15%. Meanwhile, the textural andchemical properties of the catalysts were characterized by XRD, TEM, BETand H2-TPR techniques. It was found that the modification of Co promoterimproved the dispersion of Ni species resulting in the higher stability. Additionally, a interaction between Ni, Co promoter and SBA-15supportwere found, which strongly enhanced the redox properties and the catalyticactivity of the catalysts. For bifunctional SBA-15catalysts modified withalkaline earth metal, the conversion of acetophenone and the selectivity of1-phenethyl alcohol both increased obviously. For bifunctional SBA-15catalysts modified with rare earth metal, the selectivity of1-phenethylalcohol increased.