Effect of chemical reactions on separation

Chemical reactions occur in many commonly practiced separation processes. By chemical reactions, we mean those molecular interactions in which a new species results (Prausnitz et al, 1986). In a few processes, there will he hardly any separation without a chemical reaction (e.g. isotope exchange processes). In some other processes, chemical reactions enhance the extent of separation considerably (e.g. scrubbing of acid gases with alkaline absorbent solutions, solvent extraction with complexing agents). In still others, chemical reactions happen whether intended or unintended estimation of the extent of separation requires consideration of the reaction. For example, in solvent extraction of organic acids, the extent of acid dissociation in the aqueous phase at a given pH should be taken into account (Treybal, 1963, pp. 38-41). Chemical equilibrium has a secondary role here, yet sometimes it is crucial to separation. 

The relation between the extent of separation and the extent of reaction is briefly considered in Section 5.1. How chemical reactions alter the separation equilibria in gcts-liquid, vapor-liquid, liquid-liquid, solid-liquid, surface adsorption equilibria, etc., is described in Section 5.2. The role of chemical reactions in aitering the separation in 

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This book has 118 separate numerical examples spread over Chapters 1-4 and 6-9. The numerical examples are not in finer print. Chapter 5 has sometimes employed numerical calculations to illustrate the effect of chemical reactions on separations without formal numerical examples. Chapter 10 follows this strategy as well to illustrate the amount of energy required for a particular separation. The total number of problems provided at the ends of all the chapters is 299. The specific separation process relevant for the problem is generally obvious from the introductory sentence in the problem. Further, the sequence of appearance of a problem on a given separation process reflects/follows the sequences of appearance of that separation process in the text. 

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