Life time ultrasound

Hydrogenation of xylose to xylitol is an important process in the production of sweeteners, and the sponge nickel catalyst (often called Raney-Ni) deactivates in the slurry reactor. In successive batches, the catalyst activity declines, and it has to be removed after a few batches and replaced by a new one. However, by applying in situ ultrasound treatment, the catalyst deactivation was considerably suppressed as illustrated in Figure 9.32. In this way, the catalyst life time can be considerably prolonged [23]. 

Ultrasound can also be used to enhance chemical processes, for instance instead of UV or transducers and sensors can be used together for different kinds of processes. The ideal future state would be implanting micro-electrodes in the membrane and visualizing the state of the membrane and its expected life-time. Problems could arise to keep the transducers/sensors clean. 

---