BackgroundEnantioselective liquid-liquid extraction is a very attractive technology for the production of enantiomerically pure compounds. The objective of this research is to investigate enantioselective liquid-liquid extraction of valine (Val) enantiomers with metal-BINAP complexes as enantioselective extractants. ResultsResults show that BINAP complex with copper(I) as central ion allows the separation of Val enantiomers with the highest operational selectivity. Efficiency of the extraction depends, often strongly, on a number of process variables, including types of organic solvents, pH of the aqueous phase, concentration of host and substrate, and temperature. Extraction performance of the system can be accurately predicted by the model. By modeling and experiment, an optimal extraction condition was obtained at a pH of 8 and the host concentration of 2.0x10(-3)molL(-1) with the highest enantioselective () of 3.65 and performance factor (pf) of 0.086. ConclusionsThe presented data indicate that Val enantiomers can be efficiently separated by enantioselective liquid-liquid extraction. The model provides a powerful tool for calculating distribution ratio, enantioselectivity, enantiomeric excess and performance factor. It can be used for optimization of the reactive extraction systems. This paper can provide some valuable fundamental data for the production of enantiomerically pure amino acid enantiomers. (c) 2013 Society of Chemical Industry