重质芳烃油选择性加氢工艺研究

Studies on selective hydrogenation of heavy aromatic oil

以油浆抽提得到的重质芳烃油为原料,通过选择性加氢工艺降低其中有害的稠环芳烃(PAHs)化合物,得到的精制油为橡胶用环保芳烃油。实验分别对反应温度、压力、时间以及一段、二段加氢工艺对PAHs转化率的影响进行了考察,同时运用BET及EDS对2种硫化态催化剂进行了表征,以考察催化剂的活性及选择性。结果表明,Ni-W/γ-Al2O3催化剂活性及选择性较Ni-Mo/γ-Al2O3高。实验证明:通过选择性加氢可大幅度降低重质芳烃油中PAHs质量分数,一段加氢采用Ni-W/γ-Al2O3催化剂,在反应温度280℃、压力8 MPa、时间6 h的条件下,原料PAHs转化率达到46.24%;二段加氢采用Ni-Mo/γ-Al2O3催化剂,在与一段相同的反应条件下,PAHs转化率达到32.94%。经2段加氢后,产物中PAHs质量分数由起始的58.13%降到21.05%,总转化率达到63.79%,液体总收率91.72%。

With the heavy aromatic oil extracted from slurry as raw material,the polycyclic aromatic hydrocarbons（PAHs） were converted to light aromatics through selective hydrogenation.The refined oil obtained could be treated as environmental aromatic oil for rubber.The influences of reaction temperature,pressure,time and two-stage hydrogenation process on the conversion of PAHs were investigated respectively in the experiment.Moreover,the catalyst activity and selectivity were examined by BET and EDS characterization.The result shows that the activity and selectivity of Ni-W/γ-Al2O3 were higher than that of Ni-Mo/γ-Al2O3.It proves that the mass fraction of PAHs can be decreased significantly by selective hydrogenation.For the first-stage hydrogenation with Ni-W/γ-Al2O3 catalyst,the PAHs conversion rate reaches 46.24% under the optimized operating conditions of reaction temperature 280 ℃,reaction pressure 8 MPa and reaction time 6 h.For the second-stage with Ni-Mo/γ-Al2O3 catalyst,the PAHs conversion rate is 32.94% under the same conditions.After two-stage hydrogenation,PAHs mass fraction decreases from 58.13% to 21.05%;the total PAHs conversion rate can reach 63.79%,and the total yield of liquid is 91.72%.