制备因素对Ni－W／C催化剂活性及结构的影响

THE EFFECT OF PREPARATION PARAMETERS ON THE ACTIVITIES AND STRUCTURE OF Ni-W/C CATALYST

研究了以沥青活性炭为载体的Ｎｉ－Ｗ催化剂制备参数与其加氢脱硫（ＨＤＳ）、加氢脱氮（ＨＤＮ）和加氢脱芳（ＨＤＡ）活性的关系，并利用广延Ｘ射线吸收精细结构．（ＥＸＡＦ）、透射电镜（ＴＥＭ）研究了金属原子的近程配位情况及金属的分散状况．发现金属原子比、催化剂焙烧气氛和温度等对催化剂活性有较大影响．浸渍液ＰＨ值与载体ＰＨＩＥＰ的相对关系对催化活性的影响与浸渍方式有关．表征结果表明，“类ＷＳ２”结构的完整性影响了催化剂活性，焙烧气氛温度影响了金属硫化物的分散度．

The relationship between the preparation parameters of Ni--W/C catalysts and their HDS, HDN and HDA activities were studied. The structure of 'WS2-like' species and metal dispersion were investigated by EXAFS and TEM. Atomic ratio, atmosphere and temperature of calcination affect the activities of catalysts greatly. The relationship between the pH of impregnation solution and the pHIEP of supports affect the activities of catalysts in different ways, depending on impregnation sequence. EXAFS results show that Nw-s of 'WS2-like' structure is related to the activities of catalysts. Atmosphere and temperature of calcination influence the dispersion of metal sulfide.