Biphasic sonoelectrosynthesis. A review

Abstract

Electrosynthesis can be carried out in emulsions formed in situ via sonication of otherwise immiscible liquid/liquid systems. The basic physical principles underlying these experiments are introduced and illustrated via three examples: the electroreduction of liquid olefins, the Kolbe electrooxidation, and the electrogeneration of leuco-methylene green.

Electrochemistry for Biofuel Generation: Transformation of Fatty Acids and Triglycerides to Diesel‐Like Olefin/Ether Mixtures and Olefins

“…One may speculate that the glycerol oxidation leads to the formation of reaction products that, for instance, block the electrode surface for the further decarboxylation of the fatty acids. [25] HPLC analysis also confirmed the formation of glycerolderived but unidentified products. A further understanding of these processes is required to achieve a complete conversion of the starting material.…”

Electrochemical Applications of Power Ultrasound

“…There are several examples [11,57] where the increased mass transport accentuates the Faradaic processes compared to other background currents (Figure 4.5).…”

Ultrasonically Enhanced Voltammetric Analysis and Applications: An Overview

“…Examples are several [12,58] in which the beneficial effect are exemplified by the inherent increased mass transport to the electrode in which useful Faradaic processes are accentuated in comparison with −background× currents. Ultrasound is also a powerful technique for creating emulsions in immiscible systems; transient collapse at the biphasic interface creates effective homogenization.…”

“…Sonoemulsions or −acoustic emulsions× are of high potential for electrosynthesis due to the avoidance of stabilizing reagents; suspended depolarizers are added as droplets in water, which under insonation are forcefully transported to the electrode surface which will allow otherwise impossible electrochemistry. Furthermore, water is ideal as a reaction environment for organic electrochemical processes with good conductivity and polarity and straight forward product isolation by extraction or filtration [58]. This is exemplified by the electrosynthesis of methylene green in which the organic phase constantly extracts the products preventing any possible electrode passivation [58].…”

“…Furthermore, water is ideal as a reaction environment for organic electrochemical processes with good conductivity and polarity and straight forward product isolation by extraction or filtration [58]. This is exemplified by the electrosynthesis of methylene green in which the organic phase constantly extracts the products preventing any possible electrode passivation [58]. …”