ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Application of vacuum membrane distillation for concentration of organic solutions‡

Marek Gryta and Marta Waszak

^aInstitute of Inorganic Technology and Environment Engineering, West Pomeranian University of Technology, Ul. Pułaskiego 10, 70-322 Szczecin, Poland

E-mail: marek.gryta@zut.edu.pl

Abstract: Vacuum membrane distillation was used to concentrate organic solutions containing mainly 1,3-propanediol, ethanol and carboxylic acids. The studied solutions were permeates obtained from nanofiltration process applied for the separation of broths from the fermentation of glycerol with the Citrobacter freundii bacteria. The presence of organic solutes decreased the surface tension of permeates to the value of 47 mN m⁻¹. However, the pores inside the used polypropylene membranes were not wetted by the post-fermentation solutions, and they were concentrated to over five-fold. It was shown that vacuum membrane distillation has over twice higher thermal efficiency compared to that obtained by direct contact membrane distillation.

Keywords: acuum membrane distillation – fermentation broth – glycerol – 1,3-propanediol

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2016-0002

Chemical Papers 70 (6) 737–746 (2016)