| Carbon dioxide(CO2)is one of the most abundant and inexpensive Ci resources in the nature.It is also one of the most important factors leading to the greenhouse effect.Thus,it is of great value and significance to fix and utilize the carbon dioxide.Because of the stable physical and chemical properties of CO2,Electrochemical method of directly converting CO2 into free radicals is a more reasonable reaction route.Besides,the process is relatively simple and safe;the reaction conditions are mild and pollution-free.Therefore,the electrochemical method to fix CO2 is a very effective method.In this paper,the electrochemical reduction reaction and mechanism of benzyl bromide,methanol and chalcone was studied based on electrochemical method.The main contents are as follows:1.The copper source and the nickel source were electrodeposited into a Cu-Ni alloy with a mass ratio of 3:1 by electrodeposition method,which were manufactured into the electrode under the sintering of muffle furnace,and the electrode performance was tested by cyclic voltammetry.2.The solubility of CO2 in different solvent systems was studied.The higher the solubility was,the higher the reaction yield would be reached.When the volume ratio of ionic liquid BMIMBF4 and benzyl bromide is 2:1,the solubility of CO2 is the highest,and the solubility is 7.25 mg in the ionic liquid BMIMBF4-benzyl bromide solution system.When the volume ratio of ionic liquid BMIMBF4 and methanol is 1.5:1,the dissolution effect is the best,and the solubility is 9.36 mg in the ionic liquid BMIMBF4-methanol solution system.3.Under mild conditions,benzyl acetate was successfully synthesized by electrochemical reduction of benzyl bromide and CO2 with ionic liquid BMIMBF4 acting as solvent and catalyst in a single cell electrolytic cell.By optimizing the experimental conditions,the optimum reaction conditions are ascertained:the reaction temperature was at room temperature(25 ?),the electrode reaction system was composed of the Cu-Ni alloy electrode acting as the working electrode and A1 rod acting as a sacrificial anode,the amount of electricity that passed through the reaction was 2.5 F-mol-1.When the electrolysis potential was controlled at-1.4 V,the reaction rate of benzyl bromide was the highest.The yield.of ethyl benzyl acetate,dimerized benzene ethane and benzyl ether were 39.4%,12.5%and 4.6%,respectively.4.The electrochemical reduction behavior of methanol and CO2 was studied by cyclic voltammetry with ionic liquid BMIMBF4 as the medium,and the dimethyl carbonate(DMC)was successfully synthesized.The experimental results show that the yield of the final product DMC was 48%when the Cu-Ni alloy was used as electrode material,the reaction temperature was 25 ?the electrolytic potential and the electrolytic power were-1.5 V and 2.0 F·mol-1,respectively.5.In the single chamber electrolytic cell,ionic liquid BMIMBF4 was used as solvent and catalyst,and ?-benzylacetophenone and 1-phenylalcohol were synthesized successfully by electrochemical reduction of chalcone.The optimal reaction conditions were determined as follows:the reaction temperature was 25 ? the Ag electrode was used as the working electrode,the Mg rod was used as the sacrificial anode,the reaction power was 2.5 F-mol"1,the electrolysis potential was-1.7 V,the electrochemical reaction rate of chalcone reached the highest.The yield of the obtained ?-benzylacetophenone was 45.2%and the yield of 1-phenylphenylpropanol was 16.2%. |
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