Predictive modeling and experimental implementation of organic acids in stream recovery by reactive extraction in membrane contactors

F. Chemarin (1, 2) , V. Athès (1) , W. Buquet (2) , M. Bedu (1) , F. Allais (2) , A.F. Teixeira (2) , Marwen Moussa (1) , Ioan-Cristian Trelea (1)

1 SayFood - Paris-Saclay Food and Bioproduct Engineering
2 ABI - Agro-Biotechnologies Industrielles

Membrane-based reactive extraction as an in situ product recovery technique is a promising strategy for process intensification, in particular in the case of the bioproduction of organic acids. Reactive extraction allows a high selectivity for the extraction of the targeted acid and the microporous membrane keeps biocatalysts in the aqueous broth while implementing a large liquid–liquid surface area and ensuring a dispersion-free contact, without problems of emulsion formation. This paper deals specifically with the extraction of biobased 3-hydroxypropionic acid using tri-n-octylamine in n-decanol. In order to maintain an effective driving force for 3-HP transfer into the organic phase, this latter was continuously regenerated by recovering the acid in a back-extraction aqueous phase, giving a complete pertraction process. A mass transfer model for this process was developed. It is based on the boundary layer theory and takes into account chemical and physical equilibria of complexation/dissociation and partitioning, species diffusion in the membrane pores and viscosity variations in the organic phase. Viscosity highly depends on acid concentration, increasing up to 50% when 3-HP concentration reaches 28 g.L-1. Thus, it was possible to predict different experimental results with R2 ≥ 0.99, totally neglecting chemical kinetics and interfacial resistance for both extraction and back-extraction steps. The model allows the prediction of extraction kinetics with (1) fixed initial concentrations and (2) with gradual 3-HP feed (mimicking a bioconversion) in transient and steady states coupled with back-extraction (globally also called pertraction). Model based analysis of mass transfer mechanisms led to the construction of a nomogram giving 3-HP stationary concentration in the case of a typical production rate, enabling for example a rapid organic phase selection or membrane sizing.

Keywords: Solvent extraction; Membrane contactor; Mass transfer modeling; Extractive bioconversion; In situ product recovery; Organic acids

Domains: Chemical engineering

F. Chemarin, V. Athès, W. Buquet, M. Bedu, F. Allais, et al.. Predictive modeling and experimental implementation of organic acids in stream recovery by reactive extraction in membrane contactors. Chemical Engineering Journal, 2022, 431 (part 2), pp.134067. ⟨10.1016/j.cej.2021.134067⟩. ⟨hal-03516921⟩