Research On Prepare Hydrogenolysis Of Dibenzofuran To O-phenylphenol Catalyst And Reaction Process

O-Phenylphenol is a widely used fine chemical that can produce antiseptic fungicides,fruit preservatives and new flame retardant materials.The method of industrial production of o-phenylphenol is cyclohexanone dimer dehydrogenation method.The catalyst for cyclohexanone dimer dehydrogenation reaction has been extensively studied,and the production process is relatively mature.The process of hydrogenation of by-product dibenzofuran in coal chemical industry to obtain o-phenylphenol is rarely studied.The hydrogenation catalyst is the key to the production of o-phenylphenol from dibenzofuran,and few people had studied this catalyst.Therefore,this paper study an hydrogenation catalyst,which opens up a new path for the production of o-phenylphenol.In this paper,a dibenzofuran hydrogenation catalyst with magnesium oxide as the carier and metal platinum as the active point was studied.The main content of the paper includes the preparation process of Pt-MgO catalyst,doping of active sites,active metal loading process and reaction process conditions.Through orthogonal experiments,the four main variables affecting the performance of the catalyst preparation process were explored.The main steps of the catalyst preparation process include preparation of magnesium oxide mixture,drying,tabletting,roasting and active metal loading.The four variables that affect the performance of the catalyst are the water content in the magnesium oxide mixture,the content of polyethylene glycol-6000,the calcination temperature,and the platinum loading.The orthogonal experiment was designed using an orthogonal table with four levels and five factors.Through the experiment,the reaction process of No.04 catalyst with a water content of 7.5 g/10g MgO,no PEG-6000,a calcination temperature of 600℃and a Pt content of 0.4%wt was obtained.Among them,the yield of o-phenylphenol is the highest,which is 38.49%wt.Characterization methods such as nitrogen adsorption desorption,carbon dioxide desorption,and hydrogen temperature programmed reduction are used to characterize the four representative groups of catalysts,revealing the relationship between the preparation process and the catalyst carrier structure.The active point doping and active metal loading process of the catalyst with better catalytic effect were investigated.The experimental results showed that the active point doping did not significantly improve the performance of the catalyst.The particle size of the catalyst and the reduction time of the catalyst have a certain influence on the catalytic reaction.It is known that the particle size of the catalyst is 20-40 mesh and the yield of o-phenylphenol is large,and the increase of the reduction time can make the catalyst tend to stable.It can be concluded that the active point doping has little effect on the performance of the catalyst,so in the later part of this paper,Explore the reaction process is mainly carried out with the catalyst No.04 that is not doped with palladium,has a particle size of 20-40 mesh and a reduction time of 4h.The main conditions of the catalytic hydrogenation include reaction temperature,reaction pressure,hydrogen flow ratio,and catalytic reaction throughput.The influence of the reaction conditions on the performance of the catalyst was investigated by a single factor method.The experiments show that the performance of the catalyst is better when the reaction temperature is 400℃,the reaction pressure is 1.0 MPa,the hydrogen flow ratio is 300,and the catalytic treatment amount is 0.5 gDBF/g-cat/h.Under good reaction conditions,the yield of o-phenylphenol was 38.16%wt.