Foam fractionation applications

Biotechnological downstream processing faces several challenges, such as dilute product streams and contained target products which are sensitive to heat, oxidation, other chemicals, etc. State-of-the-art separation methods, e.g. chromatography, are not always the best option due to variable yield losses and high costs. Foam fractionation appears as a promising alternative unit operation in biotechnological downstream processing. From its applications in metal industry and on fish farms, it was developed further towards the recovery of phytonutrients, metabolites and proteins. However, no large scale applications of foam fractionation in biotechnological downstream processing exist yet. This is due to the complexity of various biotechnological media, which makes a universalized approach for systematic process design of protein separations difficult. Ongoing research in the fields of process engineering, surface chemistry and protein chemistry can help to close this gap. Although many different substances, such as detergents, have been separated or recovered using foam fractionation, this review focuses mainly on biotechnological applications, more specifically on protein separation.

► Foam fractionation is an effective process for purification and concentration.
► Target solutes are low concentration metal ions, tensides or proteins.
► The collapsed foam represents a concentrated solute solution.
► Many interdependent parameters influence the process.