以Cr2O72-/Cr3+作为间接氧化剂电氧化环己醇制备己二酸.应用正交实验优化工艺条件,得出在原料比n(环己醇)∶n(Cr2O72-)=0.4∶1,t=35℃和CH2SO4=5mol.L-1条件下己二酸的收率可达70.29%.同时研究了Ag2SO4、(NH4)2SO4、H2SO4浓度、电流密度对Cr3+电氧化为Cr2O72-的影响,Cr3+的转化率可达82.52%.
Adipic acid was synthesized by electro-oxidation of cyclohexanol taking Cr2O72-/Cr3+ as indirect oxidant.The best technological conditions were optimized by orthogonal experiment.The optimum condition are as follows: the temperature is 35℃,ratio of crude material is n(cyclohexanol)∶n(Cr2O72-)=0.4∶1 and concentration of H2SO4 is 4 mol·L-1.Under these conditions,the yield of adipic acid can reach 70.29%.Moreover,The effects of concentration of Ag2SO4,(NH4)2SO4,H2SO4and current density on the formation of Cr2O72-were also explored.The rate of Cr3+ conversion can reach 82.52%.
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