Chair: Prof. Dr. Hans-Jörg Bart, Technische
Universität Kaiserslautern
Vice Chair: Dipl.-Ing. Werner
Bäcker, Bayer Technology Services GmbH, Leverkusen
I. Aims
The working committee extraction (founded 1976) converted 1992 to the
first common DVCV-committee of DECHEMA and GVC and is nowadays a ProcessNet
Subject Division. The primary goal is to bring together chemists and engineers in
the field of extraction. A superior task is a scientific analysis of extraction
topics and further improvement of this unit operation. However, included are
other subjects, like coalescence and break-up of droplets and droplet swarms.
In that respect all aspects related to solvent extraction and phase
separation are research issues, including hydrodynamics, mass transfer,
modeling, scale-up and apparatus design. In that respect is already a strong
initiative to model the behavior of coalescence phenomena and extraction
columns on the basis of single droplet experiments and to use non-invasive
methods (spectroscopy, flow visualization) for basic research and validations.
II. Link to other
Working Parties and Subject Divisions
The Subject Division "Extraction" usually meets once a year. Reviews or
oral presentations of current work from PhD students (20 min) are there
presented and discussed. In common events together with other working parties
plenary or keynote lectures are invited . Also reports from the triennial 'International
Solvent Extraction Conference - ISEC' are given. Here the 'Carl Hanson' medal,
a common award of DECHEMA, Frankfurt, and SCI, London, dignifies outstanding
personalities in the extraction field.
Triennially the Subject Division meeting is in conjunction with the
Subject Division "Fluid Separations", inbetween it is with other working parties or
will be hosted by industry or universities. The ProcessNet portal "Extraction"
(http://www.processnet.org/Extraktion)
gives information on the next meeting, data bases, test systems, conferences
etc.
III. Topics
The focus in the extractive application shifted from physical to
reactive systems. As an example, 20 % of the primary copper recovery is
established via reactive extraction. A new area is tailor-made chiral
selectors in its application in pharmaceutical and nutraceutical industry. Here
also deriving the raw material source from a bio-feedstock has attracted
attention. For instance, the world-wide basis for medicinal plant raw material
according FAO is 1 billion US $ per anno with a rate of growth of 6 to 8 %.
However, topics including correlation and prediction of phase
equilibria, investigations in regard to mass transfer, droplet formation and
coalescence, influence of surfactants etc. are of interest. Alternative process
concepts, like hollow fibre or micro contractors, liquid membranes, alternative
solvents (liquid CO2, ionic liquids etc.) up to solvent impregnated
resins are topics in respect to basic research or process intensification.
Phase equilibria and interfacial phenomena (Thermodynamics of complex mixtures, reactive and
ionic systems, mass transfer and kinetics, interfacial adsorption and
instabilities…)
Process engineering (Separation sequence, process simulation, permeation,
extraction, high pressure extraction, reactive extraction, hybrid systems,
on-line analytics…)
Bench scale topics (Miniplant technique, scale-up from single droplet,
coalescence…)
Apparatus selection and design (Columns, percolator, demister, decanter, population
balance modeling, CFD…)
The topics above need the co-operation of chemists and engineers with
other disciplines (interfacial physics, biotechnology, pharmacy etc.) to
further develop the scientific basis in the extraction field.
