Pilot scale processing of detergent-based aqueous two-phase systems

✍ Scribed by T. Minuth; H. Gieren; U. Pape; H. C. Raths; J. Thömmes; M. R. Kula

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 176 KB
• Volume: 55
• Category: Article
• ISSN: 0006-3592
• DOI: 10.1002/(sici)1097-0290(19970720)55:2<339::aid-bit11>3.0.co;2-c

✦ Synopsis

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 µN/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.