About the Janus double-horn sonicator and its use in quantitative homogenous sonochemistry

Quantitative sonochemical studies in the 20–100 kHz-frequency range are essentially performed by using immersion horn systems. With these systems several problems are encountered, rendering it difficult to interpret the sonochemical effects. In this paper, a new kind of sonochemical device is described: the Janus sonicator, which consists of a double immersion horn, acted on by a single pair of piezoelectric ceramics. This instrument is well adapted to the quantitative measure of effects, i.e. variations in the rate constant of a specific reaction associated to the change of an experimental parameter. Its utility will be illustrated through the study of a gas effect, a temperature effect and a surfactant effect.