间接电氧化合成对溴苯甲醛  

Synthesis of p-Bromobenzaldehyde by Indirect Electrooxidation

作　　者：胡瑞省[1] 张宏坤[1] 顾登平[1] 

机构地区：[1]河北师范大学化学学院

出　　处：《精细化工》2003年第3期169-171,181,共4页Fine Chemicals

摘　　要：提出采用间接电合成法以Ce4+/Ce3+为媒质,在高剪切混合乳化机搅拌下使Ce4+氧化对溴甲苯合成对溴苯甲醛工艺,使用后的媒质再生循环使用,无三废排放。在隔膜电解槽中Ce3+电氧化的最佳条件是c(Ce3+)=0 8mol/L;c(H2SO4)=0 3mol/L;电流密度200A/m2;电量1 0F/mol,Ce4+的电解收率90 9%。槽外合成对溴苯甲醛的最佳条件是n(Ce4+)∶n(p Br—C6H4—CH3)=4∶1;c(H2SO4)=0 3mol/L;反应温度85℃,对溴苯甲醛反应收率78 5%,Ag+催化下对溴苯甲醛反应收率90 3%。Ce3+ in sulphuric acid solution is electrooxidized to Ce4+ in a membrane electrolytic cell.Then the Ce4+ solution is mixed with pbromotoluene to produce pbromobenzaldehyde in an emulsifying stirrer.The purified mother liquid returns to the cell to be used cyclically without pollution.The optimum conditions of electrolysis are Ce3+ 08 mol/L,sulfuric acid 03 mol/L,current density 200 A/m2 and electric quantity 10 F/mol.Under these conditions the electrolytic yield is 909%.The optimum conditions of outside cell reaction are n(Ce4+)∶n(pBr-C6H4-CH3)=4∶1,sulfuric acid 03 mol/L and reaction temperature 85 ℃.Yield of pbromobenzaldehyde is 785%.With Ag+ catalyzer,the yield of pbromobenzaldehyde reaches 903%.

关 键 词：间接电氧化合成 对溴苯甲醛 对溴甲苯 

分 类 号：TQ244.4[化学工程—有机化工]