The Preparation Methods Affect Ru/C Catalyst Hydrogenation Performance Study

Supported Ru catalyst was in the precious metal catalyst that its cost was relatively lower,and its activity and stability was relatively higher than the transition metal catalyst,especially in the field of catalytic hydrogenation on the benzene ring and heterocyclic research field,it had a great application prospect.In this article,we prepared a serice of catalysts with four different methods.Namely,RuCl₃ was reduced by KBH₄ method,RuCl₃ was reduced by hydrazine hydrate method,RuCl₃ was reduced by H₂ in liquid phase and RuCl₃ was reduced by H₂ in gas phase.Then we studied the catalysts' activity on hydrogenation for benzene and heterocyclic,etc.The properties of the synthesized catalysts were characterized using X-ray diffraction?XRD?,X-ray photoelectron spectroscopy?XPS?,N2 adsorption-desorption?Brunauer-Emmett-Teller?BET?method?,and transmission electron microscope?TEM?.The main research contents and results are as follows:Adopting four different methods which had been mentioned above to prepare supported Ru catalyst?carrier such as activated carbon,TiO₂ and SiO₂ and Al₂O₃?,and studying these catalysts' activity of quinoline hydrogenation.The carrier?C,TiO₂?had higher activity than The carrier?Al₂O₃,SiO₂?.Especially,activated carbon was the best support for quinoline hydrogenation.Activated carbon as supporter,there is a small effect on the activity of Ru adding assistant Co and Fe,however,adding Cu and Ni may inhibit the activity of Ru.The catalytic properties of Ru/C prepared by four different methods:RuCl₃ was reduced by KBH₄ method,RuCl₃ was reduced by hydrazine hydrate method,RuCl₃ was reduced by H₂ in liquid phase and RuCl₃ was reduced by H₂ in gas phase.As a result,With water as solvent,0.78 mol/L quinoline,at 100 ?,2 MPa hydrogen pressure,reacting 1h,the yield of product is 100%,69%,91%,and 94%,respectively.Four of the hydrogenation activity consistent with corresponding characterization results.Then with KBH₄ reduction with high relative activity of catalyst,prepared by investigating the influence of solvent,temperature,pressure and time in the reaction,and the catalyst stability test.The activated carbon as the carrier showed better catalytic activity,so further study of Ru/C catalysts get through the catalytic hydrogenation of benzene compounds such as toluene,terephthalic acid?PTA?and phthalic acid methyl esters.The catalytic properties of Ru/C prepared by four different methods:RuCl₃ was reduced by KBH₄ method,RuCl₃ was reduced by hydrazine hydrate method,RuCl₃ was reduced by H₂ in liquid phase and RuCl₃ was reduced by H₂ in gas phase.As a result,with phthalic acid dibutyl hydrogenation at 2 Mpa hydrogen pressure,at 130 ?,reacting 1.5h,the yield of product was 99.5%,99.5%,97.2% and 7.95% respectively.Activity of KBH₄ reduction of catalysts,prepared by changing the influence of the load of Ru,assistants and the temperature of phthalic acid methyl esters hydrogenation has a certain degree of impact.With dimethyl phthalate to test its stability,the result was good.Studying the influence of different preparation methods of terephthalic acid hydrogenation,among them,RuCl₃ was reduced by KBH₄ method,its activity was up to 103.9h^-1,RuCl₃ was reduced by H₂ in gas phase,the yield of product was 82%.Because Ru/C prepared by KBH₄ is higher activity,with toluene explorating on the factors affecting the catalyst preparation,its activity was up to 2122h^-1.