Electrode Processes and Electrochemical Engineering

I. Introduction to Electrochemistry.- 1. Concept and Role of Electrochemical Engineering.- 1.1. Electrochemical Science and Technology.- 1.2. Features of Electrochemical Processes.- 2. Thermodynamics of Electrochemical Processes.- 2.1. Electromotive Force and Decomposition Voltage.- 2.1.1. Example 1: Formation and Electrolysis of Hydrochloric Acid.- 2.1.2. Example 2: Electrolysis of Water.- 2.2. Reversible Potential.- 2.2.1. Example 1: Anodic and Cathodic Reactions of HCl Electrolysis.- 2.2.2. Example 2: Hydrogen Electrode Reaction versus Oxygen Electrode Reaction.- 2.2.3. Example 3: Chlorine Electrode Process.- 2.2.4. Example 4: Sodium Amalgam Electrode.- 2.2.5. Example 5: Solid - Phase Electrodes of Mercury Compounds.- 2.2.6. Example 6: The Pourbaix Diagram for the Iron-Water System.- 3. Kinetics of Electrochemical Processes.- 3.1. The Rate of Electrochemical Process.- 3.2. Electrode Processes Controlled by a Reaction Step.- 3.2.1. Example 1: Hydrogen Electrode Process.- 3.2.2. Example 2: Oxygen Electrode Process.- 3.2.3. Example 3: Chlorine Electrode Process.- 3.2.4. Example 4: Iron Electrode Process.- 3.3. Electrode Processes Controlled by a Mass Transfer Step.- 3.3.1. Example 1: Copper Electrode Process.- 3.3.2. Example 2: Oxygen Cathode Reaction.- 3.3.3. Example 3: Fe2+ /Fe3+ Redox System.- 3.3.4. Example 4: Sodium Amalgam Electrode.- 3.4. More Complicated Electrode Processes.- 3.4.1. Electrode Process Controlled by Chemical and Mass Transfer Steps.- 3.4.2. Dimensional Analysis of Mass Transfer on an Electrode.- 4. Voltage Balance and Energy Balance in an Electrolytic Cell.- 4.1. Conductivity of Electrolytic Solutions.- 4.1.1. Specific Conductance, Molar and Equivalent Conductivities.- 4.1.2. Example 1: Conductivity of Concentrated KCl Solutions.- 4.1.3. Example 2: Conductivity of the Mixed Solution of HCl and CuCl2.- 4.1.4. Example 3: Conductivity of the Electrolyte Solutions Containing Gas Bubbles.- 4.2. Current Efficiency and Energy Efficiency.- 4.2.1. Current Efficiency.- 4.2.2. Energy Balance.- 4.3. Voltage Balance.- 4.3.1. Example 1: Electrolysis of NaCl Solutions— Comparison between the Amalgam Process and the Diaphragm Process.- 4.3.2. Example 2: Electrorefining and Electrowinning of Copper.- 4.3.3. Example 3: Application of the Oxygen Cathode to HCl Electrolysis.- II Electrochemical Industries.- 5 Water Electrolysis.- 5.1. Water Electrolyzer.- 5.2. Production of Heavy Water.- 5.3. Prospects of Water Electrolysis.- 6. Electrolysis of Hydrochloric Acid Solution.- 6.1. HCl Electrolyzers.- 6.2. Recovery of Chlorine from Hydrochloric Acid.- 7. Amalgam-Type Chlor-Alkali Industry.- 7.1. Flowsheet.- 7.2. Amalgam Cell.- 7.3. Amalgam Decomposition.- 7.3.1. Minimum Sectional Area.- 7.3.2. Minimum Height.- 7.3.3. Notes for Convenience.- 7.4. Effects of Impurities and Necessity of Brine Purification.- 8. Chlor-Alkali Industry Using Diaphragm Cells.- 8.1. Diaphragm-type Chlorine Cells.- 8.2. Ion-Exchange Membrane Cells.- 8.3. Amalgam Process vs. Diaphragm Process.- 9. Fused Salt Electrolysis and Electrothermics.- 9.1. Background of Fused Salt Electrolysis.- 9.2. Production of Aluminum.- 9.2.1. The Bayer Process for Production of Alumina.- 9.2.2. The Hall-Heroult Process for Aluminum Production.- 9.2.3. Production of High-Purity Aluminum by Means of Electrorefining.- 9.3. Electrolytic Production of Magnesium.- 9.4. Electrochemical Production of Sodium.- 9.5. Production of Calcium Carbide.- 10. Electrorefining and Electrodeposition of Metals.- 10.1. Electrochemical Production of Copper.- 10.1.1. Electrorefining of Copper.- 10.1.2. Electrochemical Winning of Copper.- 10.2. Electrodeposition of Less Noble Metals.- 10.3. Electrolytic Production of Pure Zinc.- 10.4. Initiation, Growth, and Morphology of Electrodeposited Metal.- 11. Batteries.- 11.1. Leclanché-Type Batteries.- 11.2. Lead-Acid Batteries.- 11.3. Alkali Storage Batteries.- 11.4. Fuel Cells and Application of Fuel Cell Concepts to Chemical Processes.- III. Electrochemical Engineering.- 12. Configuration of Electrolyzers.- 12.1. Configuration and Type of Electrolyzers.- 12.1.1. Case Study of Configuration of Chlor-Alkali Cells.- 12.1.2. Monopolar Cells vs. Bipolar Cells.- 12.1.3. Some Cell Configurations of Interest.- 12.2. Diaphragms and Separators.- 12.2.1. Electrochemical Systems Having Liquid Junction Potential.- 12.2.2. Mass Transfer through a Diaphragm.- 12.3. Anode Materials.- 12.3.1. Example 1: Graphite Anode for Chlorine Evolution.- 12.3.2. Example 2: Precious-Metal-Coated Anodes.- 12.3.3. Example 3: The Oxide-Coated Metal Anodes.- 12.4. Cathode Materials.- 12.4.1. Effects of Brine Impurities on the Amalgam Cathode.- 12.4.2. Low Hydrogen Overvoltage Cathodes in Alkali Solutions.- 12.4.3. Oxygen Cathodes for Chlor-Alkali Cells.- 13. Current Distribution and Potential Distribution.- 13.1. Primary Current Distribution.- 13.1.1. Example 1: Effects of the Side Wall of an Electrolytic Cell on the Current Distribution.- 13.1.2. Example 2: Effects of the Back Wall of an Electrolytic Cell on the Current Distribution.- 13.2. Effect of the Electrode Resistance.- 13.3. Secondary Current Distribution.- 13.3.1. Effect of the Overvoltage on the Current Distribution on a Resistant Electrode.- 13.3.2. Effect of the Overvoltage on the Current Distribution on a Finite-Plate Electrode.- 14. Optimum Design of an Electrolytic Cell.- 14.1. Size of Electrolyzer and Optimum Current Density—A Case Study.- 14.1.1. Optimum Size and Number of Cells.- 14.1.2. Optimum Current Density.- 14.1.3. Optimum Number of Stand-by Electrolyzers.- 14.2. Energy Saving in the Chlor-Alkali Industry.- 14.2.1. Use of off-peak Electricity.- 14.2.2. Reduction of Consumption of the Overall Energy for Processing.- 14.2.3. Reduction of the Power Consumption for Electrolysis.- 14.2.4. Voltage Balance.- 14.2.5. Bubble Effects.- 14.2.6. New Technology.- 14.3. Use of Computers.- 15. Feasibility of Electrochemical Processes.- 15.1. Production of Chlorate.- 15.1.1. Capacity, Production, and Market.- 15.1.2. Technology.- 15.1.3. Reaction Mechanisms for Electrolytic Production of Chlorate.- 15.1.4. Anode Materials.- 15.2. Electrolytic Production of Organic Compounds.- 15.2.1. Introduction.- 15.2.2. Electrochemical Synthesis of Adiponitrile: an Example of Electroorganic Chemistry.- 15.3. Safety Problems and Environmental Protection in Electrochemical Industries.- 15.3.1. Safety Problems in Electrochemical Industries.- 15.3.2. Abatement of Mercury Discharge from Chlor-Alkali Plants.- 15.4. Feasibility and Prospects of Electrochemical Processes— Conclusion.