Hydrodenitrogenation Performance Of MoP Catalysts Modifided By Rare Earth Oxides

Hydrofining includes hydrodesulfurization(HDS),hydrodenitrogenation(HDN)and hydrodeoxygenation(HDO)is an essential step of clean fuels' production.HDN and HDS always react on the catalyst simultaneously.Excellent hydrogenation capacity was request for HDN as compared with HDS,and developing catalysts with outstanding catalytic performance is indispensable.As the industrial HDN catalyst,the supported Ni(Co)-Mo-S or Ni(Co)-W-S perform low hydrogenation activity and result in weak HDN activity.Previous results confirmed that bulk MoP has excellent HDN performance.One of the most effective way to improve HDN activity is modification.So modified bulk MoP catalyst to inprove HDN performance have been studied.The content mainly include the follows.Bulk MoP and Ce(La)-modified MoP catalysts were prepared by a co-precipitation method(Ce(La)-MoP(x),where x presents the La/Mo atomic ratio)followed by XRD and N2 adsorption–desorption characterization.The characterization results indicated that bulk MoP and Ce(La)-modified MoP catalysts have been successfully synthesized,the introduction of cerium(lanthanum)oxide could enlarge surface area of catalyst and enhance the dispersion.The effect of cerium oxide on HDN reaction over MoP catalyst is studied.The HDN performances of the catalysts were studied using quinoline and decahydroquinoline(DHQ)as the model compounds.The results showed that the introduction of cerium oxide can help to improve the hydrogenation activity and C-N bond cleavage activity of MoP but inhibited the dehydrogenation of DHQ.Cerium oxide didn't change the pathway of quinoline HDN over MoP catalyst.The effect of lanthanum oxide on HDN reaction over MoP catalyst is also studied.The HDN performances of the catalysts were studied using quinoline and decahydroquinoline(DHQ)as the model compounds.The HDN results indicate that the introduction of lanthanum oxide promoted the HDN of quinoline over bulk MoP catalyst,but didn't change the pathway of quinoline HDN over MoP catalyst.The best La/Mo molar ratio is 0.3.The HDN of quinoline over the MoP catalysts occurred mainly through the DHQ pathway,and the HDN of quinoline was more enhanced by the addition of lanthanum oxide than the HDN of DHQ.Compared with lanthanum oxide,the cerium oxide is more effective on kuinoline HDN activity improvement over MoP catalyst.