插层阴离子对以类水滑石为前体Ni-Al2O3催化剂催化乙酰丙酸加氢性能的影响

分别以\mathrm{N}{\mathrm{O}}_{\mathrm{3}}^{-}以及\mathrm{C}{\mathrm{O}}_{\mathrm{3}}^{\mathrm{2}-}插层类水滑石为前体制备了Ni/Al摩尔比为3∶1的NiAl-N-R以及NiAl-C-R催化剂，并考察了其催化乙酰丙酸加氢性能。采用N₂-物理吸附、ICP-OES、TG/DTG、XRD、H₂-TPR/TPD、TEM、NH₃-TPD、in-situ Py-FTIR等表征手段对前体及催化剂进行了表征。研究结果表明，类水滑石插层阴离子对催化剂中活性金属-载体相互作用、活性金属分散度、表面酸性质以及催化乙酰丙酸加氢性能有重要影响。以\mathrm{C}{\mathrm{O}}_{\mathrm{3}}^{\mathrm{2}-}插层类水滑石为前体的催化剂表现出高的金属分散度、丰富的L酸酸性中心、高的CO加氢活性和高的循环使用稳定性。当以甲醇为溶剂、160℃、4 MPa氢气压力条件下反应1 h时，γ-戊内酯收率可达71.8%。

Effect of intercalation anions on catalytic performance of hydrotalcite-like precursor Ni-Al2O3 catalyst for levulinic acid hydrogenation

Ni₃Al-N-R and Ni₃Al-C-R catalysts with Ni/Al mole ratio of 3∶1 were prepared by using \mathrm{N}{\mathrm{O}}_{\mathrm{3}}^{-} and \mathrm{C}{\mathrm{O}}_{\mathrm{3}}^{\mathrm{2}-} intercalated hydrotalcites as precursors respectively, and their catalytic properties for the hydrogenation of levulinic acid were investigated. The precursors and catalysts were characterized by N₂-physical adsorption, ICP-OES, TG/DTG, XRD, H₂-TPR / TPD, TEM, NH₃-TPD, in-situ Py-FTIR and other characterization methods. The results showed that the intercalation anions played an important effect on the active metal-support interaction, active metal dispersion, surface acid properties, and catalytic performance of catalysts for levulinic acid hydrogenation. The catalyst derived from \mathrm{C}{\mathrm{O}}_{\mathrm{3}}^{\mathrm{2}-} intercalated hydrotalcite exhibited high metal dispersion, rich L acid acidic centers, high CO hydrogenation activity, and high recycle stability. When methanol was used as the solvent at 160℃ and 4 MPa hydrogen pressure for 1 h, the yield of γ-valerolactone could reach 71.8%.