ADVANCES IN CHEMICAL ENGINEERING Editor-in-Chief GUY B. MARIN Department of Chemical Engineering Ghent University Ghent, Belgium Editorial Board DAVID H. WEST Research and Development The Dow Chemical Company Freeport, Texas, U.S.A. JINGHAI LI Institute of Process Engineering Chinese Academy of Sciences Beijing, P.R. China SHANKAR NARASIMHAN Department of Chemical Engineering Indian Institute of Technology Chennai, India Advances in CHEMICAL ENGINEERING MICROSYSTEMS AND DEVICES FOR (BIO)CHEMICAL PROCESSES VOLUME 38 Edited by J C SCHOUTEN Eindhoven University of Technology Eindhoven, The Netherlands Amsterdam • Boston • Heidelberg • London • New York • Oxford Paris • San Diego • San Francisco • Singapore • Sydney • Tokyo Academic Press is an imprint of Elsevier Academic Press is an imprint of Elsevier Linacre House, Jordan Hill, Oxford OX2 8DP, UK 32 Jamestown Road, London NW1 7BY, UK Radarweg 29, PO Box 211, 1000 AE Amsterdam, The Netherlands 30 Corporate Drive, Suite 400, Burlington, MA 01803, USA 525 B Street, Suite 1900, San Diego, CA 92101-4495, USA First edition 2010 Copyright � 2010, Elsevier Inc. 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Alternatively you can submit your request online by visiting the Elsevier web site at http://www.elsevier.com/locate/permissions, and selecting: Obtaining permission to use Elsevier material Notice No responsibility is assumed by the publisher for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein ISBN: 978-0-12-374458-6 ISSN: 0065-2377 For information on all Academic Press publications visit our website at elsevierdirect.com Printed and bound in USA 10111213 10987654321 Working together to grow libraries in developing countries www.elsevier.com | www.bookaid.org | www.sabre.org CONTRIBUTORS AnılAg˘ıral, Mesoscale Chemical Systems, MESA + Institute for Nanotechnol­ ogy, University of Twente, 7500 AE Enschede, The Netherlands Arata Aota, Institute of Microchemical Technology, and Micro Chemistry Group, Kanagawa Academy of Science and Technology, 3-2-1 Sakado, Takatsu, Kawasaki, Kanagawa 213-0012, Japan A.J. deMello, Department of Chemistry, Imperial College London, South Ken­ sington, London SW7 2AY, UK J. C. deMello, Department of Chemistry, Imperial College London, South Ken­ sington, London SW7 2AY, UK Han J.G.E. Gardeniers, Mesoscale Chemical Systems, MESA + Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands Takehiko Kitamori, Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan, and Micro Chemistry Group, Kanagawa Academy of Science and Technology, 3-2-1 Sakado, Takatsu, Kawasaki, Kanagawa 213-0012, Japan S. Krishnadasan, Department of Chemistry, Imperial College London, South Kensington, London SW7 2AY, UK Paul Watts, Department of Chemistry, The University of Hull, Cottingham Road, Hull HU6 7RX, UK Charlotte Wiles, Department of Chemistry, The University of Hull, Cottingham Road, Hull HU6 7RX, UK; Chemtrix BV, Burgemeester Lemmensstraat 358, 6163JT Geleen, The Netherlands A. Yashina, Department of Chemistry, Imperial College London, South Ken­ sington, London SW7 2AY, UK vii PREFACE This volume of Advances in Chemical Engineering has “microsystems and devices for (bio)chemical processes” as its central theme. Four chapters are presented that cover different aspects of this theme, ranging from contin­ uous flow processing in microsystems to nanoparticle synthesis in micro- fluidic reactors. This field of microprocess technology has experienced a very large growth during the last two decades as is reflected by the even still today continuously increasing number of scientific journal publica­ tions, reviews, patents, text books, and monographs. Significant develop­ ments in the field of miniaturization of lab-scale systems and even complete plants for chemicals and materials production have been achieved. Microreactors and microfluidic devices are now being used at the industrial level in widely diverse areas, such as fuel processing, fine chemicals synthesis, functional material synthesis, high-throughput cata­ lyst screening, polymerization, and sensors and process analytics. The application field is still expanding as chemists and engineers more and more acknowledge the benefits of taking advantage of the microscale in the efficient and controlled production of chemicals and materials at so far often unprecedented operating conditions. The advantages of continuous operation at the microscale in chemicals and materials production are well described in the literature. Many exam­ ples are known in which the high rates of mass and heat transfer under well-defined and well-controlled fluid flow regimes contribute signifi­ cantly to improved conversions and yields. As a result, also new process windows are explored and new chemistries are discovered. This volume of Advances in Chemical Engineering addresses a few of these develop­ ments. In the first chapter, Arata Aota and Takehiko Kitamori discuss the need for general concepts for the integration of microunit operations in microchemical systems that are used for continuous flow processing. They focus in particular on analysis, synthesis, and construction of bio­ chemical systems on microchips, which show superior performance in the sense that these systems provide rapid, simple, and highly efficient pro­ cessing opportunities. ix x Preface In the second chapter, Anil Ag ˘iral and Han J.G.E. Gardeniers take us to a fascinating world wherein “chemistry and electricity meet in narrow alleys.” They claim that microreactor systems with integrated electrodes provide excellent platforms to investigate and exploit electrical principles as a means to control, activate, or modify chemical reactions, or even preparative separations. Their example of microplasmas shows that the chemistry can take place at moderate temperatures where the reacting species still have a high reactivity. Several electrical concepts are presented and novel principles to control adsorption and desorption, as well as the activity and orientation of adsorbed molecules are described. The rele­ vance of these principles for the development of new reactor concepts and new chemistry is discussed. The third chapter by Charlotte Wiles and Paul Watts addresses high- throughput organic synthesis in microreactors. They explain that one of the main drivers for the pharmaceutical industry to move to continuous production is the need for techniques which have the potential to reduce the lead time taken to generate prospective lead compounds and translate protocols into production. The rapid translation of reaction methodology from microreactors employed within R&D to production, achieved by scale-out and numbering-up, also has the potential to reduce the time needed to take a compound to market. The authors discuss many exam­ ples of liquid phase, catalytic, and photochemical reactions and they conclude the chapter with a selection of current examples into the synth­ esis of industrially relevant molecules using microreactors. The last chapter by A.J. deMello and his coworkers gives an overview of microfluidic reactors for nanomaterial synthesis. The authors explain that the difficulty of preparing nanomaterials in a controlled, reproducible manner is a key obstacle to the proper exploitation of many nanoscale phenomena. In the chapter, they describe recent advances in the develop­ ment of microfluidic reactors for controlled nanoparticle synthesis. In particular, recent work of their group aimed at developing an automated chemical reactor capable of producing on demand and at the point of need, high-quality nanomaterials, with optimized physicochemical prop­ erties, is highlighted. This automated reactor would find applications in areas such as photonics, optoelectronics, bioanalysis, targeted drug deliv­ ery, and toxicology where it is essential to characterize the physiological effects of nanoparticles not only in terms of chemical composition but also size, shape, and surface functionalization. The developments described in these four chapters are all part of what we call today “process intensification” which aims at process equipment innovation, enabling new manufacturing and processing methods. This has led already to interesting foresight scenarios in which it is envisaged that future leading process technology will be based on a widespread implementation and use of intensified, high-precision process equipment Preface xi and devices, including corresponding adaptation of plant management, supply chain organization, and business models. New reactor engineering options and solutions are foreseen with considerably improved energy and process efficiencies and economics. Challenging concepts are envi­ saged such as multipurpose, self-adapting, and modular process devices using advanced sensor and process analyzer technologies and program­ mable chemical reactors, whose local operating conditions adapt automa­