title: Measurement of oxygen transfer from air into organic solvents.
abstract: The use of non-aqueous organic media is becoming increasingly important in many biotechnological applications in order to achieve process intensification. Such media can be used, for example, to directly extract poorly water-soluble toxic products from fermentations. Likewise many biological reactions require the supply of oxygen, most normally from air. However, reliable online measurements of oxygen concentration in organic solvents (and hence oxygen transfer rates from air to the solvent) has to date proven impossible due to limitations in the current analytical methods.
  
  
  
  For the first time, online oxygen measurements in non-aqueous media using a novel optical sensor are demonstrated. The sensor was used to measure oxygen concentration in various organic solvents including toluene, THF, isooctane, DMF, heptane and hexane (which have all been shown suitable for several biological applications). Subsequently, the oxygen transfer rates from air into these organic solvents were measured.
  
  
  
  The measurement of oxygen transfer rates from air into organic solvents using the dynamic method was established using the solvent resistant optical sensor. The feasibility of online oxygen measurements in organic solvents has also been demonstrated, paving the way for new opportunities in process control. © 2015 The Authors.Journal of Chemical Technology & Biotechnologypublished by JohnWiley & Sons Ltd on behalf of Society of Chemical Industry.
authors: Department of Chemical and Biochemical Engineering Technical University of Denmark DK-2800 Kgs Lyngby Denmark.
authors: Hemalata
authors: H
authors: Ramesh
authors: Institute of Analytical Chemistry and Food Chemistry Graz University of Technology 8010 Graz Austria.
authors: Torsten
authors: T
authors: Mayr
authors: Institute of Analytical Chemistry and Food Chemistry Graz University of Technology 8010 Graz Austria.
authors: Mathias
authors: M
authors: Hobisch
authors: Institute of Analytical Chemistry and Food Chemistry Graz University of Technology 8010 Graz Austria.
authors: Sergey
authors: S
authors: Borisov
authors: Institute of Analytical Chemistry and Food Chemistry Graz University of Technology 8010 Graz Austria.
authors: Ingo
authors: I
authors: Klimant
authors: Department of Chemical and Biochemical Engineering Technical University of Denmark DK-2800 Kgs Lyngby Denmark.
authors: Ulrich
authors: U
authors: Krühne
authors: Department of Chemical and Biochemical Engineering Technical University of Denmark DK-2800 Kgs Lyngby Denmark.
authors: John M
authors: JM
authors: Woodley
keywords: optical sensor; organic solvents; oxygen transfer