采用专利方法制备出一种新型的γ-Al2O3,并以其为载体,制备出加氢处理催化剂MoNiP/Al2O3.用PASCA,XPS,DRS,TPR和微型反应色谱等技术对γ-Al2O3和催化剂进行了表征,考察了Ni和P两种助剂的作用.结果表明,γ-Al2O3具有较大的孔径,集中的孔分布和较高的机械强度;活性金属Mo在γ-Al2O3表面上的化学分散量(分散阈值)可达5.04～5.82μmol/m2.因而特别适合用作高活性加氢处理催化剂的载体.引入的Ni主要是同Mo/Al2O3催化剂表面上较稳定的金属-载体相互作用复合物反应,并生成类NiMoO4化合物;在MoNi/Al2O3催化剂中引入P,有利于抑制四面体配位结构的物种Mo[T],增加八面体配位结构的物种Mo[O],改善催化剂的还原性能,从而提高催化剂的加氢处理活性.助剂Ni和P的最佳含量分别为w(Ni)=4.0%和w(P)=2.6%.
Based on the characterization of a series of commercial γ-Al2O3,a new type of γ-Al2O3 has been developed. The γ-Al2O3 has larger CDA for active metal (such as Mo or W) from 5.04 to 5.82 μmol/m2, and also has larger pore diameter, concentrated pore volume distribution and higher mecha nical strength, so it can be used as a good support for hydrotreating catalysts. The MoNiP/Al2O3 catalyst has been prepared and the effect of promoters Ni a nd P was studied by means of PASCA in conjunction with XPS, DRS, TPR and microre action-chromatography. The results showed that the promoter Ni combined with 2 types of stronger metal-support interaction centers, resulting in formation of NiMoO4-like compound. The optimum Ni content is w(NiO)=4.0 % (n(Ni)/n(Mo)=0.323) in the catalyst. The promoter P plays a role in inhibiting the formation of tetrahedral structure Mo [T] and in promoting the formation of octahedral structure Mo[O]. The optimu m P content is w(P)=2.6% (n(P)/n(Mo)=0.084) in the catalyst.
参考文献
| [1] | Nag N K;Graham J R;Johns W F.NPRA Annual Meeting[M].San Fran cisco,1989:AM-89-32. |
| [2] | Scheffer B;Molhoek P;Moulijn J A .[J].Applied Catalysis,1989,46(01):11. |
| [3] | Mickelson G A .[P].USP 3-749 663,1973. |
| [4] | 何金海;罗锡辉 .[P].CN 93/107?376,1993. |
| [5] | Ache H J.Positronium and Muonium Chemistry[M].Washington D C:Am Chem Soc,1979:1. |
| [6] | Somojai G A .[J].Science,1978,201:789. |
| [7] | Luo X H;Ai J Sh;He J H .[J].Reaction Kinetics and Catalysis Letters,1991,43(01):55. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%