摘要
为了提高正构烷烃加氢异构化性能,分别采用机械复合法和原位复合法制备ZSM-5+SAPO-11分子筛和ZSM-5/SAPO-11分子筛,采用等体积浸渍法制备了以分子筛和无定型硅铝(ASA)为载体,Ni、W为活性金属的加氢裂化催化剂。通过X-射线粉末衍射(XRD)、扫描电子显微镜(SEM)、N_(2)物理吸-脱附分析仪、红外光谱仪(IR)、吡啶红外光谱仪(Py-IR)对分子筛的晶型结构、形貌、孔结构和酸性质等进行了表征,利用N_(2)物理吸-脱附分析仪和紫外-可见漫反射光谱仪(UV-Vis)对催化剂的孔结构和活性金属配位状态等进行了表征。结果表明,ZSM-5/SAPO-11分子筛更能表现出2种分子筛互相依附的形态,具有更加适宜的酸强度与酸类型分布,更有利于BrÖnsted(B)酸和Lewis(L)酸的协同作用。在相同反应条件下,以ZSM-5/SAPO-11分子筛为载体的NiW催化剂异构选择性比以ZSM-5分子筛或ZSM-5+SAPO-11分子筛为载体的NiW催化剂有明显提高。
ZSM-5+SAPO-11 molecular sieves and ZSM-5/SAPO-11 molecular sieves were prepared to improve the hydroisomerization performance of normal alkanes by mechanical compounding method and in-situ compounding method respectively.The hydrocracking catalysts were prepared using various zeolites and amorphous silica alumina(ASA)as the support and Ni,W as active metals by incipient wetness impregnation method.The framework structures,morphologies,pore structures and acid properties of the various zeolites were characterized by X-ray diffraction(XRD),scanning electron microscope(SEM),N_(2) adsorption-desorption,infrared spectroscopy(IR),pyridine adsorbed infrared spectroscopy(Py-IR),and the pore structures and the coordination state of the active metals of the corresponding catalysts were determined by N_(2) adsorption-desorption and ultraviolet and visible spectroscopy(UV-Vis).The results show that ZSM-5/SAPO-11 molecular sieves prepared by in-situ method was more capable of presenting the form of two kinds of molecular sieves attached to each other,and had a more suitable acid strength and acid type distribution,which was conducive to the synergistic effect of BrÖnsted(B)and Lewis(L)acids.Under the same reaction conditions,the isomerization selectivity of NiW catalyst with ZSM-5/SAPO-11 molecular sieve as support was significantly higher than that of NiW catalyst with ZSM-5 molecular sieve or ZSM-5+SAPO-11 molecular sieve as supports.
作者
黄文斌
魏强
周亚松
张晴
HUANG Wen-bin;WEI Qiang;ZHOU Ya-song;ZHANG Qing(State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing 102249,China;SINOPEC Engineering Incorporation,Beijing 100101,China)
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2022年第3期398-406,共9页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金(22078360)。
关键词
分子筛
催化剂
原位复合法
加氢裂化
异构选择性
molecular sieve
catalyst
in-situ composite method
hydrocracking
isomerization selectivity
