Pd-M(Ce、Ca、Fe)/γ-Al_2O_3催化2,5-二氢呋喃加氢性能

通过分步浸渍法制备了Pd含量为0.3%,M含量为3.0%的Pd-M(M=Ce、Ca、Fe)/γ-Al_2O_3催化剂,采用XRD、N_2物理吸附-脱附、H_2-TPR、H_2-TPD和Py-IR等对催化剂进行表征,并研究了助剂对Pd/γ-Al_2O_3催化剂催化2,5-二氢呋喃加氢性能的影响。结果表明,在Pd/γ-Al_2O_3催化剂中引入助剂,降低了Pd与金属相互作用,同时减少了表面暴露L酸位点;促进了2,5-二氢呋喃加氢转化为四氢呋喃,抑制了异构化产物2,3-二氢呋喃的产生。特别是Fe的引入,与Pd之间的协同作用,使CC双键在Pd表面吸附增强,2,5-二氢呋喃转化率大幅提高。该催化剂在反应温度30℃,氢压0.5 MPa和反应时间1 h的加氢条件下,2,5-二氢呋喃转化率达到94.25%,目标产物四氢呋喃选择性达到99.97%。

Hydrogenation of 2,5-dihydrofuran catalyzed by Pd-M(Ce、Ca、Fe)/γ-Al2O3

Pd-M (Ce,Ca,Fe) /γ-Al₂O₃ catalysts with Pd content of 0.3% and M content of 3.0% were prepared by step impregnation.The effects of promoters on the hydrogenation of dihydrofuran over Pd/γ- Al₂O₃ catalysts were studied by XRD,N₂ physical adsorption-desorption,H₂-TPR,H₂-TPD and Py-IR.The results showed that the introduction of additives in Pd/γ-Al₂O₃ reduced the interaction between Pd and metal,reduced the surface exposed L acid sites,promoted the hydrogenation of 2,5-dihydrofuran(2,5-DHF) to tetrahydrofuran(THF),and inhibited the production of 2,3-dihydrofuran.In particular,the introduction of Fe and the synergistic effect between Fe and Pd enhanced the adsorption of C=C double bond on the surface of Pd, and greatly improved the conversion of 2,5-DHF.The conversion of 2,5-DHF and the selectivity of THF were 94.25% and 99.97% respectively under the hydrogenation reaction temperature of 30 ℃,H₂ pressure of 0.5 MPa and reaction time of 1 h .