Modified PAM/CMC bipolar membrane was prepared after carboxymethyl cellulose (CMC) and polyacrylamide (PAM) were cross-linked by Fe3＋and glutaraldehyde, respectively. Meanwhile the ion exchange capacity and the I-V curves of the bipolar membrane as well as its co-ion transport properties were investigated. SEM photographs show that the mPAM/mCMC bipolar membrane consists of the anion layer (mPAM) and the cation layer (mCMC) with a clear interface. FTIR was applied to analyse the function group in the bipolar membrane. Furthermore, TG result exhibited a good thermal stability. The mPAM/mCMC bipolar membrane was used as a separator in the electrolysis cell for electro-generation of glyceraldehyde by using MnO2/Mn2＋as a medium in a supersonic wave bath. The electro-generated nanometer MnO2 was dispersed in the solution and used for the selective oxidation of glycerine to glyceraldehyde. Under the function of electric field, the water in the bipolar membrane (BPM) was dissociated to produce H＋and OH－. OH－ migrates in the anode chamber to neutralize H＋, which promotes the positive reaction process by eliminating the accumulation of H＋. The yield was 91.6% and the current of efficiency reached 65.5%.

Key words: bipolar membrane, polyacrylamide, carboxymethyl cellulose, glyceraldehyde, electro-catalytic oxidation, nanometer MnO2