ABSTRACT
The application of external energy in the pulsing form has, for a long time, been a common practice to improve mass transfer rates in chemical engineering units. The general principles about pulsing columns were established by Van Dijk (1935), who developed several systems to improve the efficiency of solid-liquid extraction processes at the Royal Dutch/Shell Laboratory in Amsterdam, in the 1930’s. Since then, a number of techniques, based on several principles, have been developed and adapted for their application to very different fields.
