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The objective of our work
is the development of novel chemical reactors and a fundamental
understanding of complex chemical reaction / mass-transfer systems with an
emphasis on pharmaceutical and environmental applications. Research
projects usually include experimental and numerical studies.
Reactive Mass Transfer at Dynamic
Interfaces and Multiphase Flows
Reactive flows are found in a wide variety
of industrial processes, including many chemical reactors such as
gas/liquid/solid reactors or fluidized beds. Industrial demands require the
description of complex reaction networks, viscous fluids and multiphase
flows. A strong coupling of mass and heat transfer with the flow field and
the reactive processes require sophisticated simulation methods and
experimental tools, which are developed in our group.
Specific research projects include the
analysis of fast gas-liquid-solid reactions close to interfaces (bubbles,
films), the impact of hydrodynamics on reaction selectivity in density
driven flow, and reactive mixing in catalytic monolith systems.
This research effort is supported by a
2001 NSF CAREER Award, a NSF Grant, North American Mixing Forum Young
Faculty Award, and a DuPont Young Professor Grant.
Chiral Catalysis and Pharmacaceutical
Reaction Engineering
A recent, significant increase in the use of
chiral catalysts for pharmaceutical processes, mainly due to "racemic
switches" of various drugs, requires development of new and more
active enantio-selective catalytic systems. These catalysts are typically
homogenous organo-metallic complexes. Heterogeneous catalysts, on the other
hand, offer numerous advantages over homogeneous systems, such as simple
separation and recycling of the often expensive catalyst. Our research
focuses on heterogenizing homogenous asymmetric catalysts, while increasing
stereo-selectivity, activity, and stability.
Specific research projects include the
development of heterogeneous catalysts for asymmetric hydrogenations of
imines (chiral amines), an important functional group in many
pharmaceuticals, agrochemicals, flavors, and fragrances. Other projects are
concerned with the development of leaching-free Pd Catalysts for Suzuki
Coupling Reactions. Investigations are exploring novel strategies for
anchoring current asymmetric homogeneous organometallic ligands and
catalysts onto various inorganic and polymer supports (alumina, silica,
& polymers). Reactive Calorimetry (RC1), in-situ FTIR, LC/MS,
NMR, X-Ray, and UV-Analysis are being used to monitor the catalytic system,
as well as the asymmetric reaction. Quantumchemical computations are
perfomed to study and improve catalytic cycles. Nanotemplating
of surfaces and molecular deposition techniques allow a precise control of
the location of the complex on the surface.
Other projects include sheared drying of
pharmaceuticals and nano-materials, where we are developing experimental
tools to study the agitated drying of crystals. .
Research is supported by American Chemical
Society, Bristol-Myers Squibb, Merck, Pfizer, Schering-Plough, and
Novartis.
Catalyst Manufacture
More than 90% of all chemical, agrochemical and pharmaceutical production
processes use catalysts in at least one chemical step. While there has been
significant advance in the understanding of catalysis on a fundamental
level, the highly complex process of manufacturing, i.e., the most
important step, has attracted little attention.. This situation has
recently led to the formation of the Rutgers Consortium for Catalyst
Manufacturing Science and Engineering which is directed by our group.
Experimental, computational, and theoretical tools are being used to
develop a predictive understanding of catalyst manufacture processes,
including Impregnation, Drying, Catalyst Functionalization,
Heterogenization of Organometallics and other operations. Several other
faculty are involved in this program, which is funded by the member
companies Akzo-Nobel, ChevronTexaco, Davison Catalysts Engelhard, and
UOP.
Numerical Analysis of Large Dynamical
Systems
Models of chemical reactors vary from a pair of ODEs (CSTR) to a large set
of 3-D PDEs (reactive flows). Due to the strong transport/reaction coupling
and the nonlinear dependence of the reaction rates on temperature and
concentration these models exhibit a very complex bifurcation behavior.
Multiple steady-states, spatio-temporal oscillations, and chaos are
frequently encountered. The goal of our research is to develop numerical
methods and bifurcation techniques especially for models of high dimension
by application of direct linearization and operator methods together with
novel numerical techniques (wavlet analysis, front-tracking, domain
decomposition, subspace iteration, multi-level preconditioning for iterative
solvers, etc.).
Specific projcts include development
multi-resolution/multi-domain (MRMD) methods for PDEs, bifurcation tools
using optimization and stochastic sampling, and model reduction methods.
Recently, we were the first group to be able to carry out a bifurcation
study of a 3D fixed bed reactor.
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Recent Publications
Koynov, A., Tryggvason G.
and J.G. Khinast (2005), Mass Transfer and Chemical Reactions in Bubble
Swarms with Dynamic Interfaces, AIChE J. 51
Vassylyev O., Panarello A. and J.G. Khinast, (2005) Review:
Enantioselective Hydrogenations with Chiral Titanocenes, Molecules,
10, 518–550
Panarello, A. , Vassylyev, O. and J.G.
Khinast, (2005), Preparation of Derivatized Ethylene- bis-(indenyl) Ligands
via Homogeneous Suzuki Couplings on Pd, Tet. Letters, 46, 1353-1356
Panarello, A., Vassylyev
O. and J. G. Khinast, (2005) Use of Oxirane Ring-Opening Reactions for
Synthesis of Ethylene-bis(indenyl) Ligands Containing Alkene Tethers,
SynLett 5, p.797-800
G. Viswanathan,
A. Bindal, Luss D., and J. Khinast , (2005), Stationary transversal hot
zones in adiabatic packed bed reactors, AIChEJ. 51
Koynov, A. and J.G.
Khinast (2004), Effects of hydrodynamics and Lagrangian Transport on
Chemically Reacting Bubble Flows, Chem. Eng. Sci. 59(18)
3907-3927
Wang, J. and J.G. Khinast
(2004), Analysis of the Complex Nonlinear Behavior of Reacting Bubbly
Flows, in print, Chem. Eng. Sci, 59, 5575-5585
Lekhal A., Girard K. P., Brown, M. A.,
Kiang S. , Khinast J.G. and B. J. Glasser, (2004), The Effect of
Agitated Drying on Crystal Morphology of L-Threonine, Intl. J. of
Pharmaceutics, 270, 263-277
Lekhal A., Glasser B.J. and J. G.
Khinast, Influence of pH and ionic strength on the Activity Profile of
Imprgenation Catalysts, (2004) Chem. Eng. Sci. 59,
1063-1077
Panarello, A. and J.G. Khinast (2003), Synthesis
of a novel ethylene-bis(tetrahydroindenyl) ligand containing a
functionalized four-carbon tether for heterogenizing onto solid supports,
Tetrahedron Letters, 44, 4095-4098
Khinast, J.G. , A. Koynov, and T.M. Leib,
(2003), Reactive Mass Transfer at Gas-Liquid Interfaces: Impact of
Micro-Scale Fluid Dynamics on Yield and Selectivity of Liquid-phase
Cyclohexane Oxidation, Chem. Eng. Sci., 58, 3961-3971
Raffensberger J., Koynov A., Glasser B.
and J.G. Khinast, (2003), Influence of Particle Properties on the
Yield and Selectivity of Fast Heterogeneously Catalyzed Gas-Liquid
Reactions, International Journal of Reactor Engineering, 1: A15
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