助剂对顺酐加氢制备γ-丁内酯催化剂页硅酸镍性能的影响

采用蒸氨法制备含Mo、Ce、Zn助剂的页硅酸镍催化剂,考察助剂对催化剂催化顺酐加氢制备γ-丁内酯的影响。结合N₂吸附-脱附、XRD、H₂-TPR、NH₃-TPD、TEM 、XPS等表征和活性评价对催化剂的织构性质及其催化性能进行研究。结果表明,不同性质的助剂对催化剂结构及其催化性能具有显著影响。助剂Mo的掺杂,提高催化剂中镍物种的还原,增加催化剂表面金属Ni⁰的数目,在金属和酸性位协同催化下,促进催化剂催化顺酐C≡O基加氢的能力,在反应温度160 ℃、氢气压力5 MPa、反应时间180 min条件下,γ-丁内酯产率可达21.3%,是未掺杂催化剂催化活性的1.5倍。助剂Zn和Ce的加入,降低催化剂酸性,进而降低其催化活性。

Effects of promoters on catalytic performance of nickel phyllosilicate for maleic anhydride hydrogenation to γ-butyrolactone

Effects of Mo,Ce and Zn promoters on nickel phyllosilicate (Ni-PS) catalyst prepared by ammonia distillation for hydrogenation of maleic anhydride to γ-butyrolactone were investigated.N₂ adsorption-desorption,XRD,H₂-TPR,NH₃-TPD,TEM and XPS characterization techniques combined with activity tests were carried out to explore the physicochemical properties and catalytic performance of the catalysts.The results indicated that promoters had significantly influence on structure and catalytic activity of the catalysts.The doping of Mo enhanced the reduction degree of Ni and led to more metal Ni⁰ on the catalyst surface.Due to the synergistic effect between the surface Ni⁰ and acid sites,the doping of Mo remarkably improved the activity of Ni-Si catalyst for the hydrogenation of C≡O group in maleic anhydride.At reaction temperature of 160 ℃,H₂ pressure of 5 MPa an reaction time of 180 min,yield of γ-butyrolactone was up to 21.3%,which was about 1.5 times than that of catalyst without doping.However,addition of Zn and Ce greatly reduced the acidity of the catalyst and then reduced catalytic activity.