Study On The Preparation Of SPE Membrane Electrode And The Regulation Of Selective Adsorption Of Benzene

As a clean,high-energy and abundant renewable energy,hydrogen energy has a broad application prospect in many fields such as hydrogen power generation and hydrogen fuel cell.However,the industrialization process of hydrogen energy is restricted by the development of hydrogen preparation,storage and transportation technology.The integrated hydrogen production and storage technology combining electrolytic hydrogen production and organic liquid hydrocarbon storage can maximize the selectivity of electrode and improve the hydrogenation efficiency.The precondition is to obtain the solid Polymer Electrolyte Membrane Electrode with high catalytic activity,high selectivity and chemical stability.Pt has excellent catalytic activity,but easy toxic,and its application is limited by its price.Some studies have shown that the addition of Ti can reduce the Pt load and improve the inhibition of hydrogen evolution performance of Pt based catalyst.The surface morphology and structure formed after acid treatment also have a great impact on its performance.Therefore,the key of Pt based catalyst application is to prepare binary alloy catalyst,and adjust its selective catalytic performance by post-treatment technology,which is of great significance for the development of hydrogen production and storage integration technology.In this paper,Pt Ti alloy catalyst was prepared by ion beam sputtering（IBS）.Electrochemical corrosion of the electrode carried out by adjusting the post-treatment conditions（corrosion time,corrosion concentration and corrosion temperature）in three kinds of acid etching systems（sulfuric acid,hydrochloric acid and perchloric acid）.The optimal corrosion conditions were determined by orthogonal experiment.Then Pt Ti catalyst and Nafion film were pressed in hot pressing process to get SPE membrane electrode.The catalytic activity of the electrode and the effect of temperature on the hydrogenation reaction were tested by benzene hydrogenation experiment.Characteriz Pt Ti catalyst’s inhibition of hydrogen evolution by CV and LSV.XRD,ICP-OES,SEM,HR-TEM were used to characterize the crystalline state and surface morphology.The main results are as follows:（1）Electrochemical analysis shows that the hydrochloric acid system is the best among the three corrosion systems,followed by sulfuric acid and perchloric acid.In this system,the corrosion time has the greatest influence on the sample performance,followed by the concentration of corrosion solution,and the corrosion temperature has the least influence.After 0.7mol/L hydrochloric acid and 1.5h corrosion in a constant temperature water bath at 40℃,the samples showed the best inhibition of hydrogen evolution.（2）The hydrogenation potential obtained by CV curve test is-0.5V,and the Pt Ti/C/Nafion membrane electrode has good performance tested by the benzene hydrogenation unit （liquid/liquid）.Pt Ti/C/Nafion benzene hydrogenation catalyzed reaction is diffusion controlled irreversible chemical reaction process;the exchange current density of Pt Ti/C/Nafion is 7.81×10^-7 A/cm²,which is higher than that of C/Nafion(3.42×10^-7 A/cm²).It has the characteristics of selective catalytic hydrogenation.（3）With the increase of temperature,the hydrogenation efficiency first increases and then decreases.The temperature condition is 75℃,which is more conducive to the hydrogenation reaction.At this time,the yields of cyclohexane and hydrogen are 1.040% and 0.278%,respectively.