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Ion Exchangers

  1. François de Dardel1,
  2. Thomas V. Arden2

Published Online: 15 APR 2008

DOI: 10.1002/14356007.a14_393.pub2

Ullmann's Encyclopedia of Industrial Chemistry

Ullmann's Encyclopedia of Industrial Chemistry

How to Cite

de Dardel, F. and Arden, T. V. 2008. Ion Exchangers. Ullmann's Encyclopedia of Industrial Chemistry. .

Author Information

  1. 1

    Rohm and Haas, Paris, France

  2. 2

    Cobham, United Kingdom

Publication History

  1. Published Online: 15 APR 2008

Chemistry Terms

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Abstract

The article contains sections titled:

1.Introduction
2.Structures of Ion-Exchange Resins
2.1.Polymer Matrices
2.2.Functional Groups
2.2.1.Cation-Exchange Resins
2.2.2.Anion-Exchange Resins
2.2.3.Other Types of Ion-Exchange Resins
2.3.Adsorbent Resins and Inert Polymers
3.Properties
3.1.Degree of Cross-Linking and Porosity
3.2.Exchange Capacity
3.3.Stability and Service Life
3.4.Density
3.5.Particle Size
3.6.Moisture Content
4.Ion-Exchange Reactions
4.1.Cation Exchange
4.2.Anion Exchange
4.3.Cation and Anion Exchange in Water Treatment
5.Ion-Exchange Equilibria
5.1.Dissociation and pK Value
5.2.Mono - Monovalent Exchange
5.3.Mono - Divalent Exchange (Water Softening)
5.4.General Case
6.Exchange Kinetics
6.1.Principles
6.2.Kinetic Curves
6.3.Strongly Acidic or Strongly Basic Resins
6.3.1.Film Diffusion
6.3.2.Particle Diffusion
6.4.Weakly Acidic or Weakly Basic Resins
7.Practical Consequences of Ion-Exchange Equilibrium and Kinetics
7.1.Operating Capacity, Regeneration Efficiency, and Regenerant Usage
7.2.Permanent Leakage
7.3.Water Analysis
7.4.Calculations in the Design of Ion-Exchange Plants for Water Purification
7.5.Example of Calculation
7.5.1.Principle
7.5.2.Basic Data
7.5.3.Demineralization Unit
7.5.4.Polishing Unit
8.Industrial Use of Ion Exchange
8.1.Description of the Ion-Exchange Cycle
8.2.Methods for Overcoming Equilibrium Problems
9.Ion-Exchange Resin Combinations
9.1.Pretreatment
9.2.Softening
9.3.Demineralization (Primary System)
9.4.Polishing
9.5.Choice of Resin
10.Plant Design
10.1.General Considerations
10.2.Fixed-Bed Ion-Exchange Units
10.2.1.Column Diameter and Bed Depth
10.2.2.Small-Scale Units
10.2.3.Industrial Co- and Counterflow Plants
10.2.4.Mixed Beds
10.2.5.Other Ion-Exchange Polishers
10.3.Continuously Circulated Ion-Exchange Resins
10.4.External Valves and Pipework
10.5.Control Systems
11.Special Processes in Water Treatment
11.1.Removal of Organic Matter
11.2.Treatment of Potable Water
11.3.Treatment of Brackish Water
11.4.Processes Involving Sea Water
11.5.Treatment of Condensates
11.5.1.Conventional Resins
11.5.2.Powdered Resins
11.6.Water Treatment in the Nuclear Industry
11.7.Production of Ultrapure Water
12.Special Applications of Ion Exchange
12.1.Processing Steps
12.1.1.Purification
12.1.2.Ion Substitution
12.1.3.Recovery and Concentration
12.1.4.Separation
12.1.5.Diffusion
12.1.6.Catalysis
12.1.7.Dehydration
12.1.8.Coalescence on Oleophilic Resins
12.1.9.Liquid Ion Exchangers
12.1.10.Ion-Exchange Membranes
12.2.Technical Considerations