Quenching and Flooding

Some reactions can be stopped by adding a suitable component. This is sometimes possible for catalytic reactions where a catalyst killer can be added in small amounts. For pH-sensihve reactions, a pH modification may also slow down or even stop the reaction. In these cases, the addition of only a small amount of a compound will suffice. Agitation is a critical factor, especially to ensure that a small amount of an inhibitor must be dispersed homogeneously in a large volume of reaction mixture. In order to achieve a fast and homogenous dispersion, often the vessel containing the inhibitor is pressurized, for example, nitrogen and nozzles are used to spray it into the reaction mass. 

Calorimetric methods are of great help in designing such measures, since they measure the heat of mixing, which is often important They also verify that the resulting mixture is thermally stable. 

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