纳滤技术分离谷氨酸和盐混合液的研究

Separation of L-Glu from NaCl solution by nanofiltration

考察了五种纳滤膜在高盐浓度下对溶液的脱盐性能,选择NF270进一步考察了pH值、氯化钠浓度、膜通量、搅拌速度对纳滤膜分离性能的影响.实验结果表明,虽然高盐浓度对膜表面的电荷屏蔽作用严重,但随着pH值的增加,NF270对谷氨酸的截留率增加,膜的分离选择性也同时增加,而跨膜压力随着pH值的增加而减小.在选择合适的膜通量和搅拌速度时,NF270对谷氨酸的截留率达到95.0%,膜的分离选择性达到18.8,可以实现高盐浓度下谷氨酸溶液的脱盐.

Separation of L-Glu from highly concentrated NaCI solution by nanofiltration （NF） was investigated with five nanofiltration membranes. The effect of various experimental parameters such as pH, concentration of NaCI, permeate flux and stirring speed on the separation performance of NF270 was studied. The results showed that the rejection of L - Glu and membrane selectivity of NF270 increased with increase in pH, though the existence of large amount of salt shielded the electrostatic interaction between electrolytes and the membrane. However, the transmembrane pressure decreased with increasing pH. Under suitable conditions, the rejection of L- Glu and membrane selectivity of NF270 were 95.0% and 18.8, respectively ,suggesting that it is possible to effectively separate L- Glu from highly concentrated NaCI solution.