Microstructured Devices for Chemical Processing

Dr. Madhvanand Kashid, Chemical Engineer, at Syngenta Crop Protection Monthey SA, Switzerland. He secured PhD in Chemical Engineering from Technical University of Dortmund, Germany, on "liguid-liquid slug flow capillary microreactors". Prior to joining Syngenta, he worked at Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland. He had been extensively working on different aspects of microprocess engineering such as design and characterization of microstructured devices both by mathematical modelling and experimental validation, development of continuous process with industrial partners, and application of microdevices for educational purpose. He is the co-author of 25 scientific publications, reviews and book chapters.Prof. Dr. Albert Renken, Professor Emeritus, secured PhD and habilitation from University of Hannover and joined EPFL in 1977. He has been working on variety of topics related to chemical and polymer reaction engineering such as multiphase reactions, heterogeneous and enzymatic catalysis and micro reactor technology. He represents Switzerland in the Working Party on Chemical Reaction Engineering in the European Federation of Chemical Engineering. In 2007 he got the DECHEMA-Titan-Medal for his pioneering contributions to Chemical Reaction Engineering and Microreaction Technology. He is author or co-author of more than 450 scientific publications, 3 textbooks and co-author of the "Handbook of Micro Process Engineering". His actual research and teaching is focused on sustainable chemical production and process intensification.Prof. Dr. Lioubov Kiwi-Minsker, Head of the Group of Catalytic Reaction Engineering, GGRC, at Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland . Prof. Kiwi-Minsker received her PhD in 1982 in physical & colloidal chemistry from Moscow University, her habilitation in 1992 from the Novosibirsk University in Physical Chemistry and joined EPFL in 1994. Her teaching and research activities continue to be in the field of Heterogeneous Catalysis and Reactor technology, in particular, the reactors with structured catalytic beds and micro-reactors. She is the co-author of more than 200 scientific publications, patents and book chapters. She is currently a member of the Working party on "Chemical Reaction Engineering" and "Process Intensification" of the European Federation of Chemical Engineering (EFCE) and of the European Federation of Catalysis (EFCATS).

• Preface XIList of Symbols XIII1 Overview of Micro Reaction Engineering 11.1 Introduction 11.2 What are Microstructured Devices? 21.3 Advantages of Microstructured Devices 21.3.1 Enhancement of Transfer Rates 21.3.2 Enhanced Process Safety 51.3.3 Novel OperatingWindow 71.3.4 Numbering-Up Instead of Scale-Up 71.4 Materials and Methods for Fabrication of Microstructured Devices 91.5 Applications of Microstructured Devices 101.5.1 Microstructured Reactors as Research Tool 111.5.2 Industrial/Commercial Applications 111.6 Structure of the Book 131.7 Summary 13References 142 Basis of Chemical Reactor Design and Engineering 192.1 Mass and Energy Balance 192.2 Formal Kinetics of Homogenous Reactions 212.2.1 Formal Kinetics of Single Homogenous Reactions 222.2.2 Formal Kinetics of Multiple Homogenous Reactions 242.2.3 Reaction Mechanism 252.2.4 Homogenous Catalytic Reactions 262.3 Ideal Reactors andTheir Design Equations 292.3.1 Performance Parameters 292.3.2 BatchWise-Operated Stirred Tank Reactor (BSTR) 302.3.3 Continuous Stirred Tank Reactor (CSTR) 352.3.4 Plug Flow or Ideal Tubular Reactor (PFR) 392.4 Homogenous Catalytic Reactions in Biphasic Systems 452.5 Heterogenous Catalytic Reactions 492.5.1 Rate Equations for Intrinsic Surface Reactions 502.5.2 Deactivation of Heterogenous Catalysts 572.6 Mass and Heat Transfer Effects on Heterogenous Catalytic Reactions 592.6.1 External Mass and Heat Transfer 602.6.2 Internal Mass and Heat Transfer 692.6.3 Criteria for the Estimation of Transport Effects 832.7 Summary 842.8 List of Symbols 86References 873 Real Reactors and Residence Time Distribution (RTD) 893.1 Nonideal Flow Pattern and Definition of RTD 893.2 Experimental Determination of RTD in Flow Reactors 913.2.1 Step Function Stimulus-Response Method 923.2.2 Pulse Function Stimulus-Response Method 933.3 RTD in Ideal Homogenous Reactors 953.3.1 Ideal Plug Flow Reactor 953.3.2 Ideal Continuously Operated Stirred Tank Reactor (CSTR) 953.3.3 Cascade of Ideal CSTR 963.4 RTD in Nonideal Homogeneous Reactors 983.4.1 Laminar Flow Tubular Reactors 983.4.2 RTD Models for Real Reactors 1003.4.3 Estimation of RTD in Tubular Reactors 1053.5 Influence of RTDon the Reactor Performance 1073.5.1 Performance Estimation Based on Measured RTD 1083.5.2 Performance Estimation Based on RTD Models 1103.6 RTD in Microchannel Reactors 1153.6.1 RTD of Gas Flow in Microchannels 1173.6.2 RTD of Liquid Flow in Microchannels 1183.6.3 RTD of Multiphase Flow in Microchannels 1223.7 List of Symbols 126References 1274 Micromixing Devices 1294.1 Role of Mixing for the Performance of Chemical Reactors 1294.2 Flow Pattern and Mixing in Microchannel Reactors 1364.3 Theory of Mixing in Microchannels with Laminar Flow 1374.4 Types of Micromixers and Mixing Principles 1434.4.1 Passive Micromixer 1444.4.2 Active Micromixers 1544.5 Experimental Characterization of Mixing Efficiency 1584.5.1 Physical Methods 1584.5.2 Chemical Methods 1594.6 Mixer Efficiency and Energy Consumption 1714.7 Summary 1724.8 List of Symbols 173References 1735 Heat Management by Microdevices 1795.1 Introduction 1795.2 Heat Transfer in Microstructured Devices 1815.2.1 Straight Microchannels 1815.2.2 Curved Channel Geometry 1895.2.3 Complex Channel Geometries 1915.2.4 Multichannel Micro Heat Exchanger 1915.2.5 Microchannels with Two Phase Flow 1935.3 Temperature Control in Chemical Microstructured Reactors 1955.3.1 Axial Temperature Profiles in Microchannel Reactors 1975.3.2 Parametric Sensitivity 2015.3.3 Multi-injection Microstructured Reactors 2125.4 Case Studies 2215.4.1 Synthesis of 1,3-Dimethylimidazolium-Triflate 2215.4.2 Nitration of Dialkyl-Substituted Thioureas 2225.4.3 Reduction of Methyl Butyrate 2235.4.4 Reactions with Grignard Reagent in Multi-injection Reactor 2245.5 Summary 2265.6 List of Symbols 226References 2286 Microstructured Reactors for Fluid–Solid Systems 2316.1 Introduction 2316.2 Microstructured Reactors for Fluid–Solid Reactions 2326.3 Microstructured Reactors for Catalytic Gas-Phase Reactions 2336.3.1 Randomly Micro Packed Beds 2336.3.2 Structured Catalytic Micro-Beds 2356.3.3 CatalyticWall Microstructured Reactors 2386.4 Hydrodynamics in Fluid–Solid Microstructured Reactors 2396.5 Mass Transfer in Catalytic Microstructured Reactors 2436.5.1 Randomly Packed Bed Catalytic Microstructured Reactors 2446.5.2 Catalytic Foam Microstructured Reactors 2456.5.3 CatalyticWall Microstructured Reactors 2466.5.4 Choice of Catalytic Microstructured Reactors 2536.6 Case Studies 2556.6.1 Catalytic Partial Oxidations 2556.6.2 Selective (De)Hydrogenations 2576.6.3 Catalytic Dehydration 2596.6.4 Ethylene Oxide Synthesis 2596.6.5 Steam Reforming 2606.6.6 Fischer–Tropsch Synthesis 2616.7 Summary 2616.8 List of Symbols 262References 2627 Microstructured Reactors for Fluid–Fluid Reactions 2677.1 Conventional Equipment for Fluid–Fluid Systems 2677.2 Microstructured Devices for Fluid–Fluid Systems 2687.2.1 Micromixers 2697.2.2 Microchannels 2717.2.3 Microstructured Falling Film Reactor for Gas–Liquid Reactions 2727.3 Flow Patterns in Fluid–Fluid Systems 2737.3.1 Gas–Liquid Flow Patterns 2737.3.2 Liquid–Liquid Flow Patterns 2807.4 Mass Transfer 2847.4.1 Mass Transfer Models 2857.4.2 Characterization of Mass Transfer in Fluid–Fluid Systems 2867.4.3 Mass Transfer in Gas–Liquid Microstructured Devices 2877.4.4 Mass Transfer in Liquid–Liquid Microstructured Devices 2967.4.5 Comparison with Conventional Contactors 2997.5 Pressure Drop in Fluid–Fluid Microstructured Channels 3007.5.1 Pressure Drop in Gas–Liquid Flow 3017.5.2 Pressure Drop in Liquid–Liquid Flow 3047.6 Flow Separation in Liquid–Liquid Microstructured Reactors 3077.6.1 Conventional Separators 3087.6.2 Types of Microstructured Separators 3087.6.3 Conventional Separator Adapted for Microstructured Devices 3157.7 Fluid–Fluid Reactions in Microstructured Devices 3157.7.1 Examples of Gas–Liquid Reactions 3177.7.2 Examples of Liquid–Liquid Reactions 3197.8 Summary 3237.9 List of Symbols 324References 3258 Three-Phase Systems 3318.1 Introduction 3318.2 Gas–Liquid–Solid Systems 3318.2.1 Conventional Gas–Liquid–Solid Reactors 3318.2.2 Microstructured Gas–Liquid–Solid Reactors 3338.3 Gas–Liquid–Liquid Systems 3468.4 Summary 3478.5 List of Symbols 347References 348Index 351