Sep. Purif. Technol.

Two electrodialysis processes: two-compartment bipolar membranes electrodialysis and modified traditional electrodialysis, were developed to recover glutamic acid from isoelectric supernatant. High recovery ratio of glutamic acid was obtained by these two methods. The pretreatment degree of isoelectric supernatant, initial concentration of glutamic acid and operation voltage significantly affected the average transfer rate of glutamic acid, average current efficiency and energy consumption. Energy consumption was reduced by gradually adjusting the operation voltage in the modified traditional electrolysis. Comparison of the two electrodialysis processes indicated that the modified traditional electrodialysis was more efficient method than two-compartment BMED. Higher recovery ratio of glutamic acid and lower energy consumption were obtained by the modified traditional electrodialysis. (c) 2007 Elsevier B.V. All rights reserved.Two electrodialysis processes: two-compartment bipolar membranes electrodialysis and modified traditional electrodialysis, were developed to recover glutamic acid from isoelectric supernatant. High recovery ratio of glutamic acid was obtained by these two methods. The pretreatment degree of isoelectric supernatant, initial concentration of glutamic acid and operation voltage significantly affected the average transfer rate of glutamic acid, average current efficiency and energy consumption. Energy consumption was reduced by gradually adjusting the operation voltage in the modified traditional electrolysis. Comparison of the two electrodialysis processes indicated that the modified traditional electrodialysis was more efficient method than two-compartment BMED. Higher recovery ratio of glutamic acid and lower energy consumption were obtained by the modified traditional electrodialysis. (c) 2007 Elsevier B.V. All rights reserved