title: Pilot scale processing of detergent-based aqueous two-phase systems.
abstract: Detergent based aqueous two-phase systems have several specific properties, e.g., extreme small density differences between the two liquid phases (0.003-0.005 g/cm(3)), low interfacial tensions (5-10 microN/m) and complex rheological behavior of the product containing detergent-rich phase, which make processing difficult. We describe the successful separation of these aqueous two-phase systems in the pilot scale (1-20 kg) in the presence and absence of microbial cells, either by settling under gravity or in centrifugal separators. The performance of self-desludging liquid-liquid separators and of a nozzle separator was analyzed in detail to judge large scale application. With a feed rate of 16 L/h, stable operation was possible in the desludging machine. Up to 56 L/h could be processed with very close control of the hydrodynamic balance. In a small nozzle separator, feed rates of 90 L/h could be realized, but the purity of the separated phases and the yield of the top phase was slightly lower than in the liquid-liquid separator. The presence of surface-active components in the feed may alter the separation characteristics of the phase systems significantly. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 339-347, 1997.
authors.affiliation: Institute für Enzymtechnologie der Heinrich-Heine Universität Düsseldorf, Forschungszentrum Jülich, D-52426 Julich, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Minuth
authors.forename: H
authors.initials: H
authors.lastname: Gieren
authors.forename: U
authors.initials: U
authors.lastname: Pape
authors.forename: H C
authors.initials: HC
authors.lastname: Raths
authors.forename: J
authors.initials: J
authors.lastname: Thömmes
authors.forename: M R
authors.initials: MR
authors.lastname: Kula