分子筛调变氧化铝载体对Ni-Mo催化剂加氢脱氮活性的影响

分别以SAPO-5,Beta,Y分子筛与拟薄水铝石打浆成型制备载体,然后在载体上负载Ni-Mo金属组分制备成加氢催化剂,考察了氧化铝载体中引入不同类型分子筛对催化剂酸性、金属形貌与加氢脱氮性能的影响。NH_3-TPR,Py-IR,H_2-TPR,HR-TEM等表征结果表明:与单纯采用氧化铝载体制备的催化剂相比,载体中引入分子筛提高了催化剂的酸强度与酸量,调变了载体表面性质,减小了MoS_2片晶长度,增加了片晶的堆积层数,分子筛类型不同对催化剂的酸性与金属形貌影响程度亦有所差异。4种催化剂对焦化蜡油加氢脱氮性能的评价结果表明:氧化铝载体中引入分子筛可提高催化剂的加氢脱氮活性,加氢活性高的催化剂对非碱性氮脱除的选择性高,氢解活性高的催化剂对碱性氮脱除的选择性高。

EFFECT OF ADDING MOLECULAR SIEVE ON HYDRODENITROGENATION ACTIVITY OF Ni-Mo/Al2O3 CATALYST

The carriers were prepared by beating and modeling SAPO-5, Beta, Y molecular sieves and pseudo-boehmite, respectively. The hydrodenitrogenation (HDN) catalysts were prepared by loading Ni-Mo metal components on the prepared carriers. The influence of different types of molecular sieves adding into alumina carrier on catalyst acidity, metal morphology and HDN performance were investigated. The characterization results of NH3-TPR, Py-IR, H2-TPR, HR-TEM indicated that compared with pure alumina carrier catalysts, the introduction of molecular sieve increases catalysts acidity amount and strength, modifies carrier surface property, decreasing MoS2 lamella length but increasing stacked layers number. Different types of molecular sieves have different impacts on the catalysts acidity and metal morphology. The evaluation results of HDN of coke gasoil illustrated that introducing molecular sieves into alumina carrier improves the HDN activity of catalysts; the catalysts with high hydrogenation activity have a higher selectivity to non-basic nitrogen removal, while the catalysts with high hydrogenolysis activity have a higher selectivity to basic nitrogen removal.