title: Fractional reactive extraction for symmetrical separation of 4-nitro-D,L-phenylalanine in centrifugal contactor separators: experiments and modeling.
abstract: The enantioselective liquid-liquid extraction of 4-nitro-D,L-phenylalanine (D,L-Nphy) using PdCl2 {(s)-BINAP} as extractant in dichloroethane was studied experimentally in a countercurrent cascade of 10 centrifugal contactor separators (CCSs) at 5°C, involving flow ratio, extractant concentration, and Cl(-) concentration. The steady-state enantiomeric excess (ee) in both stream exits was 90.86% at a 93.29% yield. The predicted value was modeled using an equilibrium stage approach. The correlation between model and experiment was satisfactory. The model was applied to optimize the production of both enantiomers in >97% ee and >99% ee. 14 stages and 16 stages are required for 97% ee and 99% ee for both enantiomers, respectively.
authors.affiliation: Department of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Hunan, China.
authors.forename: Kewen
authors.initials: K
authors.lastname: Tang
authors.forename: Ping
authors.initials: P
authors.lastname: Wen
authors.forename: Panliang
authors.initials: P
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
keywords: 4-nitro-D,L-phenylalanine; enantioselective liquid-liquid extraction; multistage model; optimization; simulation