BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:Kinetic modelling of batch slurry reactions
DTSTART:20120622T101500
DTEND:20120622T111500
DTSTAMP:20260405T202936Z
UID:dad036676716dfdd8bbae7fb7e09fb2f510bc1cb2f980dea3c330441
CATEGORIES:Conferences - Seminars
DESCRIPTION:Prof. Paul J. Gemperline\, Department of Chemistry\, East Caro
 lina University\, Greenville\, USA.\nSlurries are widely used in important
  chemical and pharmaceutical manufacturing processes. In this presentation
  we report chemical monitoring and modeling of batch slurry reactions usin
 g optical and calorimetric measurement where key analytes are present in b
 oth the solid and liquid phases.  Experimental studies were performed to:
 \n\n(1)      Generate supersaturated solutions for the development of
  kinetic models of seeded crystallization\, crystal growth\, and dissoluti
 on\;\n\n(2)      Generate unseeded crystallization from homogeneous r
 eaction mixtures for the development of kinetic models of reacting systems
 \, including crystal growth as well as measurement of crystallization driv
 en by cooling of reaction mixtures including the necessary corresponding s
 olubility curves as a function of temperature\;\n\n(3)      Reproduce
  at laboratory scale\, a commercially relevant slurry reaction starting wi
 th heterogeneous reaction mixture\, producing a product slurry.\n\n\n\nSim
 ultaneous UV/visible attenuated total reflectance (ATR) and NIR reflectanc
 e measurements enabled reliable characterization of reaction mixtures and 
 detection of the onset of crystallization. Kinetic models for dissolution\
 , seeded crystallization\, unseeded crystallization\, homogeneous reaction
  and crystallization driven by cooling were successfully developed relatin
 g the mass of substance in the solution phase and solid phase to UV/Vis AT
 R and NIR reflectance measurements. Reactive crystallization experiments w
 ith kinetic modeling demonstrated that simultaneous measurements of slurri
 es with UV/Vis ATR and NIR reflectance is an effective means of characteri
 zing the dissolved fraction and the onset of nucleation and crystallizatio
 n.\n\n\n\nWork with research partner DuPont Crop Protection Science includ
 ed development of a 4 L glass reactor with a recirculation loop and sampli
 ng system for off-line HPLC analysis. Several different sampling strategie
 s were tested to develop a robust\, reproducible method for off-line HPLC 
 analysis.  NIR reflectance measurements of slurry reactions at DuPont wer
 e demonstrated to be relevant to the property of interest. Kinetic models 
 were obtained for product and reactant from NIR reflectance measurements. 
 Reaction progression was followed by depletion of triazine heterocycle\, a
 s indicated by N-H overtone band dissipation. Spectroscopic evidence of a 
 precipitation event was also observed and confirmed by focused beam reflec
 tance measurements (FBRM). Kinetic models of reaction measurements provide
 d clear resolution of two components\, the solid phase reactant and solid 
 phase product. Initial product appearance in the kinetic model concentrati
 on profile estimates corresponded temporally with the spectroscopic eviden
 ce of precipitation. Estimation of spectral profiles from kinetic models i
 nclude an N-H overtone band observed around 2010nm.
LOCATION:ME C2 405 http://plan.epfl.ch/?room=ME%20C2%20405
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR