论文部分内容阅读
采用等体积浸渍法制备了NiO质量分数6%、La2O3添加量不同的La2O3-NiO/HMCM-56催化剂,考察了La2O3添加量和工艺条件对C9+重芳烃加氢脱烷基反应性能的影响,并采用XRD、H2-TPR、NH3-TPD和BET等技术对催化剂的物化性质进行了研究。实验结果表明,添加La2O3可以提高NiO在催化剂上的分散性,改变催化剂的酸性分布与酸量,改善了催化剂的加氢脱烷基性能;在实验范围内,随La2O3添加量的增加,加氢脱烷基反应的深度增加,C9+重芳烃转化率及苯、甲苯和二甲苯(统称BTX)收率增大,但二甲苯的选择性在La2O3添加量(质量分数)为3%时达到最大。采用La2O3添加量为3%的La2O3-NiO/HMCM-56催化剂,在460℃、3.0MPa、重量空速3.62h-1及V(H2)∶V(C9+)=1600的条件下,C+9重芳烃的转化率、BTX收率及BTX选择性分别为75.23%,63.36%,84.23%。
La2O3-NiO / HMCM-56 catalysts with 6% NiO content and different La2O3 additions were prepared by the same volume impregnation method. The effects of La2O3 dosage and process conditions on the hydrodealkylation of C9 + heavy aromatics were investigated. The physicochemical properties of the catalysts were investigated by XRD, H2-TPR, NH3-TPD and BET techniques. The experimental results show that the addition of La2O3 can improve the dispersibility of NiO on the catalyst, change the acid distribution and the acid content of the catalyst, and improve the hydrodealkylation performance of the catalyst. In the experimental range, with the addition of La2O3, hydrogenation The depth of dealkylation increased, the conversion of C9 + heavy aromatics and the yield of benzene, toluene and xylene (collectively BTX) increased, but the selectivity of xylene reached the maximum when the content of La2O3 was 3% (mass fraction). Using La2O3-NiO / HMCM-56 catalyst with 3% La2O3 dosage, C + 9 (C9 +) was obtained under the conditions of 460 ℃, 3.0MPa, WHSV 3.62h-1 and V The conversion of heavy aromatics, BTX yield and BTX selectivity were 75.23%, 63.36% and 84.23%, respectively.