反萃分散组合液膜分离提取氨基酸

Separation and Extraction of Amino Acids with Strip Dispersion Hybrid Liquid Membrane

建立了分离提取蛋氨酸、亮氨酸、苯丙氨酸和色氨酸的磷酸二(2-乙基己基)酯(D2EHPA)-煤油-HCl反萃分散组合液膜体系,考察了料液相pH值、载体D2EHPA浓度、液膜相与反萃相体积比、反萃相组成、料液相与反萃分散相流速、传输时间以及支撑膜重复使用次数对氨基酸渗透系数和传输效率的影响。在优化的条件下,建立的反萃分散组合液膜体系对4种氨基酸均可以获得大于35%的传输效率,其中色氨酸和亮氨酸的传输效率超过了79%,且传输效率呈Et,Trp>Et,Leu>Et,Phe>Et,Met的趋势。支撑膜重复使用25次,对氨基酸的传输效率没有明显改变。建立的液膜体系对考察的氨基酸展示了较高传输效率和优越的传输选择性,是一种简单和环境友好的分离技术。

A method on the separation and extraction of L-methionine （Met）, L-leucine （Leu）, L-phenylalanine （Phe）, and L-tryptophan（ Trp）, using a strip dispersion hybrid liquid membrane（SDHLM） containing di-（2- ethylhexyl） phosphoric acid（D2EHPA） with kerosene as the organic liquid membrane phase and HC1 solution as the aqueous strip solution, is developed. The effects of pH in the feed solution, the concentration of the carrier（ D2EHPA）, the volume ratio of the organic liquid membrane solution to the aqueous strip solution, the strip solution composition, the flow rates of the feed solution and the strip dispersion phase, the extraction time, and reuse times of the support membrane on the permeability coefficient and the transport efficiency of amino acids were investigated. Under the optimal conditions, the transport efficiencies obtained for the four 0 amino acids, Met, Leu, Phe, and Trp were all higher than 35% , and ＇more than 79% of transport efficiencies were obtained for Leu and Trp. The transport efficiency exhibits a trend of E1.Trp 〉 Et.Leu 〉 Et,phe 〉 Et,Met. With the 12 h-extraction time, the support membrane could be reused for at least 25 times with little decrease in the transport efficiency of amino acids. The developed method with high transport efficiency and excellent transport selectivity for the studied amino acids is simple and environmental friendly.