Cyclic voltammetric behavior of electrooxidation of Mn(Ⅱ) under ultrasound and without ultrasound were compared. With the ultrasound irradiation the reduction peak potential of Pb(Ⅳ)/ Pb(Ⅱ) was found shifted negatively about 0.14 V, initial electrolytic potential reduced 0.2 V and reduction peak current increased. At the same conditions,the conversion of Mn(Ⅱ) was increased. The optimum conditions for electrooxidation were 0.3 mol/L solution of Mn(Ⅱ), 6 mol/L H 2SO 4, electrolysis potential 2.3 V and 44 W ultrasound.
A simultaneously potentiometric titration method for determinating benzaldehyde and benzoic acid in electrosynthesis product is reported. The interferences from benzyl alcohol and toluene were examined. The determination method has advantages of high precision, good reproducibility, easiness in operation and rapidity. The RSD and recovery of benzaldehyde and benzoic acid in synthesis sample is 0.33%, 1.30% and 97.76%, 101.27%, repectively.
