Advantages of synthesis in continuous flow include faster scaling from lab to production, enhanced heat and mass transfer characteristics, safer synthesis of potentially dangerous compounds, isolation of air and moisture sensitive chemistry, and reduction of hazardous waste.
Synthesis applications are further enhanced by optimization as well as mechanistic and kinetic information gained from integrating reaction components with sensors, actuators, and automated fluid handling. Moreover, flow systems allow experiments on well-defined samples at conditions not easily accessed by conventional means, such as reaction at high pressure and temperatures. Opportunities arising from on-line measurements are illustrated with studies of reaction screening, determination of chemical kinetics, and optimization of reaction conditions.
Flow chemistry also provides opportunities for continuous synthesis of nanostructures of interest as active elements in many applications, including photovoltaics, displays, and bio-chem sensing. In particular the technique promises to resolve difficulties irreproducibility of size, size distribution, and quality of the nanomaterial associated with batch synthesis. The ability to work at elevated temperatures and pressures while confining potentially toxic, high reactive starting materials is particularly important for the synthesis of novel nanostructured materials.
Cases studies are drawn from chemical synthesis and nanoparticle synthesis (metals, ceramics, and semiconductors) with particular focus on reactions enabled by flow systems and are difficult to perform by conventional techniques. Extraction and distillation are incorporated as examples of work-up techniques enabling small scale multistep chemical synthesis. Handling of solids in flow often present difficulties and is discussed along with examples of chemical transformations involving solid formation and nucleation studies.
Biography
Professor Klavs F. Jensen is the Warren K Lewis Professor and Head of the Department of Chemical Engineering at Massachusetts Institute of Technology. He received his MSc from Technical University of Denmark in 1976 and his PhD from the University of Wisconsin – Madison in 1980, in chemical engineering. He then joined the department of Chemical Engineering and Materials Science at the University of Minnesota when he became a Professor in 1988, eventually moving to MIT in 1989.
Professor Jensen’s research interests are in microfabrication, testing, integration and scale-up of microfluidic systems for chemical and biochemical discovery, synthesis and processing. He received the Allan P. Colburn Award in 1987, the Charles M.A. Stine Award of the Materials Engineering and Sciences in 1995 and the R. H. Wilhem Award in 2000, from the American Institute of Chemical Engineers. A member of National Academy of Engineering (2002), a Fellow of the Royal Society of Chemistry (2004), he became a Member of the American Academy of Arts and Sciences in 2008 and a Fellow of the American Institute of Chemical Engineers in 2009. In 2008, he was named one of the “One Hundred Chemical Engineers of the Modern Era” as part of the American Institute of Chemical Engineers Centennial.