A series of NiW/γ-Al2O3 catalysts with different P contents were prepared by equal volume impregnation with γ-Al2O3 as carrier.Catalytic hydrogenation was carried out by using fixed bed hydrogenation unit.The physical and chemical properties of the catalyst and the product oil were characterized by XRD,N2 adsorption-desorption,NH3-TPD,SEM,FTIR and GC-MS.The results show that the specific surface area and pore size of the catalyst after P modification are decreased,the mesopores and macropores are increased,the content of P is in the range of 0.8％-1.6％(w),and the catalyst sulfide component is evenly distributed on the catalyst surface.The addition of additive P increased the total acid amount of the catalyst first and then decreased,and NiWP-0.8 was the largest.The acidity distribution changed.The results show that the addition of auxiliaries to the catalyst contributes to the hydrogenation of coal tar.When the amount of additive P is 0.8％,the content of paraffins and naphthenes in the product oil is the maximum,while the content of aromatics and other compounds is the minimum.The activity of hydrodesulfurization,hydrodenitrogenation,aromatic hydrogenation and hydrodeoxygenation were the highest.The removal rate of S and N in the oil was more than 97％.%以γ-Al2O3为载体,采用等体积浸渍法制备了一系列不同P含量的NiW/γ-Al2O3催化剂,并采用固定床加氢装置对催化剂进行评价.通过XRD、N2吸附-脱附、NH3-TPD、SEM、FTIR、GC-MS等方法对催化剂的物化性质及产品油进行了表征.表征结果显示,P改性后催化剂的比表面积和孔径减小,中孔和大孔增多;助剂P含量(w)在0.8％～1.6％的范围内,催化剂硫化态组分在催化剂表面分布均匀;助剂P的加入使催化剂总酸量先增加后降低,催化剂NiWP-0.8的总酸量最大;酸性分布发生变化.实验结果表明,催化剂中加入助剂P有助于煤焦油的加氢轻质化.当助剂P的加入量为0.8％(即催化剂NiWP-0.8)时,产品油中链烷烃和环烷烃含量为最大值,而芳烃和其他化合物含量为最小值;加氢脱硫、加氢脱氮、芳烃饱和加氢和加氢脱氧反应活性最高;产品油中S,N脱除率均达到了97％以上.
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