Ni基双金属催化剂加氢脱氧性能的研究

Studies on nickel-based bimetallic catalysts for hydrodeoxygenation

考察了Ni-M/γ-Al2O3(M=Co、Cu、Fe、La)双金属催化剂对醇、酸、酮有机含氧化合物(丁醇、丁酸、丁酮)的加氢脱氧性能,并对其中间产物进行了考察。通过TPR、XRD表征手段对Ni基催化剂的还原性能、表面分散度等特性进行了研究。结果表明,Ni基催化剂中第二活性组分相对不同有机含氧化合物表现出不同的加氢活性和选择性。对于丁酸,在Ni基催化剂中加入Fe表现出较好的活性;对于丁醇,加入La有较好的加氢脱氧性能;而对于丁酮,加入Cu更有利于提高催化剂的脱除性能。醇和酯是有机酸在Ni/γ-Al2O3催化剂上加氢转化的中间产物。

The products from Fischer-Tropsch synthesis process, without S, N and aromatic hydrocarbons, are clean and environmentally friendly. But they contain a large number of alkene and oxygenates, especially acid oxygenates, which erode equipment and need to be hydrorefined. Therefore, the study on the novel hydrodeoxygenation catalysts for F-T synfuels is of great significance. Hydrodeoxygenation of oxygenates （n-butanonide, butyric acid and butanone） and intermediate products were investigated over Ni-M/γ -Al2O3 （ M = Co, Cu, Fe, La） catalysts. The influences of reducing behavior and surface dispersion of the catalysts on the catalytic performance were intensively studied. The results show that Cu and La facilitate the reduction of the NiO, but adding Co makes it difficult to be reduced. Co, Cu, Fe and La all increase the dispersion degree of NiO on the surface of the catalysts in the order of Co 〉 Fe 〉 La 〉 Cu, which can improve the catalytic activity. The Ni/γ -Al2O3 catalysts added different metals show different activity and selectivity. Nickel-based catalyst with Fe as a promoter demonstrates better activity to butyric acid;adding La in nickel-based catalyst results in better performance of hydrodeoxygenation to n-butanonide; nickel-based catalyst with Co metal is more beneficial to improve the deoxygenation to butanone. Besides, n-butanonide and butyric ester are intermediate products in the course of hydrogenation of butyric acid.