Ni-Mo/TiO_2催化剂上二苯并噻吩与4,6-二甲基二苯并噻吩的加氢脱硫反应规律

Hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene over Ni-Mo/TiO_2 catalyst

采用高压滴流床反应器,以二苯并噻吩(DBT)与4,6-二甲基二苯并噻吩(4,6-DMDBT)的正辛烷溶液作为模型溶液,在不同的反应温度、氢压、氢油体积比、液时空速(LHSV)、模型化合物初始质量分数的条件下,考察了DBT和4,6-DMDBT在Ni-Mo/TiO2催化剂上的加氢脱硫反应(HDS)规律。结果表明:提高反应温度以及增大氢油体积比均有利于DBT和4,6-DMDBT加氢脱硫反应的进行;氢分压对DBT和4,6-DMDBT转化率的提升也有很大影响,对4,6-DMDBT转化率的提升效果较大,但当氢分压较大时,增大氢分压对两者转化率的影响均较小。在反应温度350℃、氢压7 MPa、液时空速6 h-1、氢油体积比450、DBT和4,6-DMDBT初始质量分数分别为2.0%和0.2%的条件下,DBT的转化率可达98.80%,4,6-DMDBT的转化率可达98.12%。

Hydrodesulfurization（HDS） reaction of dibenzothiophene（DBT） and 4,6-dimethyldibenzothiophene（4,6-DMDBT） was studied over Ni-Mo/TiO2 catalyst in a high-pressure trickle-bed reactor.The HDS activity of Ni-Mo/TiO2 catalyst was examined using the model solution of DBT,4,6-DMDBT and n-octane as raw materials at various reaction temperatures,hydrogen pressures,hydrogen/oil volume ratios,liquid hourly space velocities,and initial concentrations of model compounds.The results showed that the conversion of DBT and 4,6-DMDBT increased with the increase of reaction temperature and volume ratios of hydrogen/oil.It was found that hydrogen pressure had great influence on the conversion of DBT and 4,6-DMDBT,especially for 4,6-DMDBT.However,when the hydrogen pressure was high enough,it exerted little influence on both.The conversion of DBT and 4,6-DMDBT could reach 98.80% and 98.12%,under conditions of the reaction temperature of 350 ℃,hydrogen pressure of 7 MPa,hydrogen/Oil volume ratio of 450,liquid hourly space velocity of 6 h-1,initial DBT mass fraction of 2.0%,and initial 4,6-DMDBT mass fraction of 0.2%.