存在4,6-DMDBT时喹啉、吲哚和咔唑在Ni-Mo加氢催化剂上加氢脱氮自抑制作用

 在S质量分数(w(S))为849μg/g的4,6-DMDBT甲苯溶液中，分别添加不同量的喹啉、吲哚和咔唑，采用Ni-Mo加氢催化剂，在280℃、总压力2 MPa、V(H2)/V(Oil)为300、液时空速5 h-1的条件下进行加氢实验，考察4,6-DMDBT存在时喹啉、吲哚和咔唑在Ni-Mo加氢催化剂上加氢脱氮自抑制作用。结果表明，添加喹啉当N质量分数达到455 μg /g时没有出现加氢脱氮自抑制现象，脱氮率在3种氮化物中最低。喹啉的部分加氢产物四氢喹啉是产生自抑制的主要物质。添加吲哚和咔唑在实验的N质量分数范围内均出现加氢脱氮自抑制现象，其部分加氢产物二氢吲哚、吲哚氮烷基取代产物N-乙基-吲哚、四氢咔唑是产生自抑制的主要物质。咔唑的加氢脱氮自抑制作用比吲哚低。

SELF-INHIBITION FOR HDN OF QUINOLINE,INDOLE AND CARBAZOLE OVER Ni-MO CATALYST IN THE PRESENCE OF 4,6-DMDBT

The hydrodenitrogenation (HDN) experiments of quinoline, indole and carbazole, respectively, in the 4,6-DMDBT toluene solution with w(S) of 849 g/g were carried out under the conditions of 280℃，total pressure 2MPa, V(H2)/V(Oil) 300 and the liquid hourly space velocity 5 h-1, to investigate self-inhibition for HDN of the three nitrogen-containing compounds over Ni-Mo catalyst in the presence of 4,6-DMDBT. According to the rate of HDN, the pathways of reaction and the change of products, quinoline had no self-inhibition effect for HDN, even the N mass fraction was 455 μg/g in the presence of 4,6-DMDBT. The conversion of quinoline was 97% and the rate of HDN was 7%, which was the lowest in the three-containing compounds. The product of part hydrogenation of quinoline, tetrahydroquionline, had self-inhibition effect for HDN. In the range of N mass fraction used in this experiment, indole and carbazole both had self-inhibition effect for HDN, which was mainly from their part hydrogenation products, indoline and tetrahydrocarbazole, also the product of N alkyl substitution of indole, N-ethyl-indole. The self-inhibition effect for HDN of carbazole was lower than that of indole.