Abstract :
In sonochemistry the effects of high power ultrasound in liquids are harnessed for chemical benefit. Apart from streaming, which induces local mixing in the process medium, the main sonophysical effect is cavitation, which not only enhances local mass transfer, but brings about mechanical damage at solid-liquid interfaces, localised extremes of temperature and pressure (the `hot-spot´ mechanism), and transient electrical effects. Depending upon the process in question, these effects manifest themselves in increased reaction rate, easier initiation, less extreme process conditions and changes in reaction path or selectivity. For some technologists, perhaps less familiar with recent advances, there remain, some questions regarding the usefulness of ultrasound to developing processes and the feasibility of using the technique at scale in demanding industrial environments. It is these two questions which are addressed in the paper
