Production of iminodiacetic acid by electrodeionization with bipolar membrane

In view of some inherent disadvantage of traditional technique, a special electrodeionization(BMEDI) process coupled with bipolar membrane was developed to produce iminodiacetic acid (IDA) from iminodiacetic acid disodium salt (IDANa₂). The BMEDI stack comprises three compartments which are separated with two bipolar membranes, one cation exchange membrane and one anion exchange membrane. The influences of operation time, current density and IDANa₂ concentration on the operating performances were investigated. The results show that with current density of 10 mA-cm^-2 and IDANa₂ concentration of 0.1 mol-L^-1, the recovery rate of IDA could reach 86.7%. It was indicated that the recovery rate of IDA and energy consumption increased as current density increased, and current efficiency increased as IDANa₂ concentration increased.