Description:
<jats:title>Abstract</jats:title><jats:p><jats:bold>Recent results in mathematical modelling of liquid/liquid extraction columns</jats:bold>. Flow in extraction columns is so complicated that it defies exact description. Methods have to be found for approximating the actual state, which can be accomplished by modelling. Approximations should be sought which closely approach reality, and yet can be formulated mathematically and solved by expenditure of a reasonable amount of effort. The development of models proceeded from the plug flow assumption via the theory of back‐mixing to mechanistic models, which should also correctly describe the fundamentals of the various processes. It is now also possible to simulate complicated processes, such as parameter changes along the height of the column. The models described in this article can be readily solved numerically. Only standard procedures are used which can be managed by minicomputers.</jats:p>