Unit operations, liquid systems reactivation

Reactive distillation is a unit operation in which chemical reaction and distillation are carried out simultaneously within a fractional distillation apparatus. Reactive distillation may be advantageous for liquid-phase reaction systems when the reaction must be carried out with a large excess of one or more of the reactants, when a reaction... 

Reactive distillation columns incorporate both phase separation and chemical reaction in a single unit. In some systems, they have economic advantages over conventional reac-tor/separation/recycle flowsheets, particularly for reversible reactions in which chemical equilibrium constraints limit conversion in a conventional reactor. Because both reaction and separation occur in a single vessel operating at some pressure, the temperatures of reaction and separation are not independent. Therefore, reactive distillation is limited to systems in which the temperatures conducive for reaction are compatible with temperatures conducive for vapor-liquid separation. 

The reactor system may consist of a number of reactors which can be continuous stirred tank reactors, plug flow reactors, or any representation between the two above extremes, and they may operate isothermally, adiabatically or nonisothermally. The separation system depending on the reactor system effluent may involve only liquid separation, only vapor separation or both liquid and vapor separation schemes. The liquid separation scheme may include flash units, distillation columns or trains of distillation columns, extraction units, or crystallization units. If distillation is employed, then we may have simple sharp columns, nonsharp columns, or even single complex distillation columns and complex column sequences. Also, depending on the reactor effluent characteristics, extractive distillation, azeotropic distillation, or reactive distillation may be employed. The vapor separation scheme may involve absorption columns, adsorption units,... 

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