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BESE Seminar - Professor Geert-Jan Witkamp

Start Date: May 21, 2017
End Date: May 21, 2017

TITLE: Research for concepts for production processes or separations with minimised footprint
DATE: Sunday, May 21, 2017
TIME: 1:30 - 2:30 p.m.
LOCATION: Building 2 · Level 5 · Room 5220

In a likely future, a significant part of the energy required by mankind (currently 2.1013 W useful energy or exergy) will be harvested directly from the overwhelming 2.1017 W of solar radiation which reaches the earth. Inorganic materials like metals, salts, or water are to be recycled or drawn from almost infinite source, while the replenishment of organic products such as plastics or transportation fuels drives a strong desire for renewable organic material replacing fossil sources. Ideally, the (bio-)chemical and physical processes creating these materials are atom-  and energy-efficient processes. The below described activities are all meant to contribute to such a framework.
The presentation will, after a quick introduction on global exergy flows, cover activities in the group on crystallisation, supercritical carbon dioxide, and natural deep eutectic solvents, and subsequently focus on crystallisation from aqueous solutions. Finally, a selection of new potential leads is presented.
Crystallisation is, after distillation, the most widely applied industrial process, and its occurrence in nature does not need any further elaboration. 
With a complete water cycle in mind, recovery of pure water, salts, trace elements and valuable compounds from aqueous streams at a certain concentration factor inevitably involves crystallisation. There can for instance be scaling of sparingly soluble salts on membranes or on the walls of pipes or reactors, suspension crystallisation of compounds as sodium chloride, and trace impurities will also fall out at a certain point as solids.
As a cheaper alternative to evaporative crystallisation, eutectic freeze crystallisation has been developed in Delft up to the point of industrial demonstrations in a full continuous 200 L crystalliser at location for various applications: magnesium sulfate winning, soda winning from a stream ex petrochemical industry, nickel sulfate winning and purification, liquid manure separation. Other applications include sodium chloride crystallisation from brine concentrate ex-groundwater purification, ammonium sulfate, ammonium phosphate, copper sulfate, oil coproduced brine (Kuwait), shale gas produced water (Shell), product recovery from fermentation etc. 
Combinations of bulk crystallisation with extraction, ion exchange or trace compound crystallisation will be discussed. 
These new technologies might bring an ideal closer, where aqueous streams are completely split into useful compounds, consuming not much more than what is thermodynamically required using solar energy, thus allowing for desalination of 0.5 m3 of seawater per 24 hrs per m2. 
Examples of potential new research leads are: finding natural deep eutectic solvents in nature, e.g. in drought and heat resistant plants; demonstrate a phosphoric acid plant featuring element recovery and production of construction grade calcium sulfate byproduct; development of light-driven selective trace element recovery with separation factors >1010; development of surfaces containing a matrix of sensors and actuators to locally detect and treat scaling e.g. with ultrasound; apply ultra-trace elements as natural tracers in process systems and nature studies; work out irreversible thermodynamics of cryogenic crystallisation processes, etc.
Prof.dr. Geert-Jan Witkamp has been since 1998 full professor at the Delft University of Technology, Chair of Process Equipment at the Mechanical Engineering faculty. Currently, his position is at the Biotechnology Dept. of the Delft University of Technology.
CV: MSc Chemistry (Leiden), Ph.D. (Delft), Academy of Arts and Sciences  KNAW research fellow (1990-95), industry (consultant, company, fertiliser industry), associate professor (till 1997). Since 1998 full professor (Delft), mainly in crystallisation technology and in sustainable industrial solvents (supercritical carbon dioxide, ionic liquids, natural deep eutectic solvents).
  About 50 PhD's, >20 patents, >200 journal publications, founded Eutectic Freeze Crystallisation programme, cofounder of  NADES  (Natural Deep Eutectic Solvents) concept, delivered best TU Delft MSc of 2005 (Kroon) and 2009 (Pingen), received KNAW DOW Energy Prize, Young Chemist's Award (KNCV, Royal Dutch Chemical Society), Most Entrpreneurial Scientist Award of TU Delft and the  Environmental Chemistry Prize (KNCV) for dissertation. 

More Information:

​​EMAIL: g.j.witkamp@tudelft.nl​