| Heavy aromatics hydrogenation to benzene, toluene, xylene preparation (BTX) were studied in this paper. A series of catalysts which are on the heavy aromatics hydrodealkylation with different MoO3and NiO as primarily active components and with HMCM-56and Hβ as supporters were prepared through different methods, and hydrodealkylation catalyst performance were investigation and research.In the early of experiment, it is the main task to look for a method which could load the active component to disperse on the surface of zeolite.In the late of the experiment, A series of catalysts with MoO3and NiO as active component,CeO2as auxiliaries were prepared and their performance were investigated in the heavy aromatics hydrodealkylation and looked for the optimal conditions of the reaction.The results showed that:The active component could be well introduced into the molecular sieves with the ion exchange process method and the catalysts have a good catalytic activity. However, the most amount of active component is about0.7%with the method. It could load more MoO3component with the method which combines the ion exchange process method with impregnation.The catalyst that has the best activity is loaded by the ion exchange process of introducing the MoO3of0.63%content and the content of0.5%by impregnation. Compared to the ion-exchange program introduction, the combined method has no obvious advantage. These indicates it is more important that the dispersion of the active ingredient than the content of the active component on the catalyst performance. In the surface of the catalyst, the MoO3and NiO could form a good synergy. The composite catalyst is modified by CeO2, and it has the best performance with the content of0.7%CeO2. In the process conditions:T=460℃, P=3.0MPa, WHSV=3.62h-1, V (H2):V (C9+)=1600, the conversion of the heavy aromatics hydrodealkylation was67.74%, the yield of BTX was62.24%,and the selectivity of BTX was67.74%. |
PDF Full Text Request