Author(s): Dingkang Xia; Kunpeng Su; Jianhua Wu; Xinming Zhang
Linked Author(s): Jianhua Wu
Keywords: Cavitation intensity; Sonochemical yields; Particle size; Particle concentration; Acoustic attenuation
Abstract: Since the cavitation intensity in solid-liquid mixtures is difficult to predict, it is of necessity to investigate the influence of suspended solids on sonochemical reactions. Tests were carried out using an ultrasonic apparatus and glass beads were fully suspended in water, considering three volume fractions (0.05, 0.075, and 0.10 v/v) and two particle sizes (0.28 and 0.45 mm). Based on iodometry, the I3 - concentration was measured, which is used to investigate the production of free radicals (‧OH) whose quantities indicate cavitation intensity. Results reveal that, with the addition of solid particles, the I3 - concentrations are lower than the solids-free case. When volume fraction increases or particle diameter decreases, the I3 - concentration decreases accordingly, which indicates lower intensity of cavitation. The attenuation of ultrasonic waves propagating in solids suspensions is theoretically investigated, and may act as a reasonable explanation for the reduction in sonochemical yields.