Additives Modification Process Research Of CoMo/TiO₂-Al₂O₃ Hydrodesulfurization Catalyst

In recent years,more and more human demand for petroleum products,with the oil production increase year by year,heavy oils phenomenon more and more serious,and increasingly strict environmental laws in many countries around the world.At present our country's gasoline and diesel quality is bad,how to removing more sulfur is the key to improve the quality of gasoline,diesel and produce clean oil chemical products.The traditional Ni Mo,CoMo base catalyst,in normal operation,it is difficult to reach the standard of low sulfur content.Unless,reducing the liquid hourly space velocity,increasing the reaction temperature and higher pressure,but these methods can lead to catalyst deactivation quickly,low life expectancy and low productivity.Therefore,an urgent need to develop a highly active hydrodesulfurization?HDS?catalysts to meet the depth of the oil hydrodesulfurization.This paper studied the CoMo/TiO₂-Al₂O₃ catalyst,mainly from the preparation of hydrodesulfurization catalyst carrier,active component of the dosage of additives and modification,etc.CoMo/TiO₂-Al₂O₃ catalyst mainly TiO₂-Al₂O₃ compound oxide as the catalyst carriers load active component,investigated the influence of different methods on the physical properties of the composite carrier,using improved sol-gel method?SG?,coprecipitation method?CP?,the surface precipitation?PR?and mechanical kneading method?ME?to prepare TiO₂-Al₂O₃ cpmposite carrier.After determined the preparation methods of composite carrier,we measured the experiment determined the active components in composite carrier TiO2 and the best ratio of Al2O3 by the same load.Under the condition of molybdenum cobalt atom ratio 0.4,active component by co-impregnation method to load on the composite carrier,we optimization of the load of molybdenum cobalt.This paper explores the influence of complexing agent on CoMo/TiO₂-Al₂O₃ catalyst,we analysed the catalyst by XRD,BET and SEM methods and evaluation of hydrodesulfurization catalyst activity.The experiment mainly from the selection of complexing agent,the load of complexing agent,the order of complexing agent and whether the catalyst calcined after adding complexing agent,etc.This paper also explores the effect of the phosphorus on CoMo/TiO₂-Al₂O₃ catalyst,we analysed the catalyst by XRD,BET and SEM methods.We studied the phosphorus add the order and add quantity,the result show that the best add order is co-impregnation and the best load quantity is 3%wt,the thiophene conversion rate reaching 98.66%.