Model‐Based Analysis and Optimization of an ISPR Approach Using Reactive Extraction for Pilot‐Scale l ‐Phenylalanine Production

Based on experimental data from fermentation runs, as well as from l ‐phenylalanine ( l ‐Phe) separation studies, a simple model is presented that describes the total ISPR approach for on‐line l ‐Phe separation. While fermentation process modeling via a macrokinetic model revealed an l ‐Phe inhibition constant of 20 ± 1.35 g/L using recombinant E. coli cells, the reactive‐extraction process modeling identified the l ‐Phe cation diffusion in the aqueous donor film and the transport of the lowly soluble carrier/ l ‐Phe complex in the aqueous acceptor film as the most dominant transfer steps. The corresponding mass transfer coefficients were estimated as k PheD = 128 × 10 −7 cm/s (extraction) and k CPheA = 178 × 10 −5 cm/s (back‐extraction). Simulation studies were performed for the total ISPR approach, which gave hints for strategies of further process optimization.