L-色氨酸的气浮络合萃取及其分离机制

Flotation complexation extraction of L-tryptophane and the mechanism of its separation

应用气浮络合萃取技术(FCE),实现了水溶液中微量L-色氨酸的分离富集。对气浮络合萃取工艺进行了研究,并对L-色氨酸气浮络合萃取的动力学以及机制进行了探讨。结果表明,与传统的络合萃取技术相比,气浮络合萃取在萃取效率和有机溶剂用量上都有明显的优势;在常温、L-色氨酸水溶液300 mL、质量浓度为20 mg/L、初始pH 6.0、浮选溶剂为P204-正己烷溶液(P204体积分数为80%)10.00 mL、NaC l摩尔浓度0.20 mol/L、通N2流速40mL/m in的条件下,气浮络合萃取分离水溶液中L-色氨酸的分配系数可达80;L-色氨酸的气浮络合萃取过程符合2.5级动力学,且主要受L-色氨酸与P204之间的络合反应控制。

Flotation complexation extraction （FCE） has been successfully employed to separate and concentrate trace amounts of L-tryptophane from aqueous solution and the kinetics and mechanism of the separation process have been investigated. The principles of the FCE technique have also been studied. Compared to traditional complexation extraction （ CE）, FCE is significantly better in terms of both separation efficiency and volume of organic solvent required. For separation at room temperature, using 300 mL of 20 mg/L L-tryptophane aqueous solution, with an initial pH of 6.0, 10. 00 mL of n-hexane solution containing bis （2-ethylhexyl） phosphate （P204） （ φ （P204） = 80% ）, NaCI with a concentration of 0.20 mol/L and a nitrogen flow rate of 40 mL/min, the distribution ratio of L- tryptophane with FCE aqueous solution can reach as high as 80. The investigation of FCE kinetics indicated that the FCE separation process for L-tryptophane had order 2.5, and is mainly controlled by the complexation reaction between L-tryptophane and P204.