Department of Environmental Engineering, Kumoh National Institute of Technology, Gumi 39177, Republic of Korea.
Department of Environmental Engineering, Kumoh National Institute of Technology, Gumi 39177, Republic of Korea.
Ultrason Sonochem. 2020 Jul;65:105065. doi: 10.1016/j.ultsonch.2020.105065. Epub 2020 Mar 11.
The use of a 20-kHz probe-type sonicator irradiating downward in a 500 mL vessel was optimized for the enhancement of the sonochemical activity in terms of the geometric and operational factors. These factors included the probe immersion depth (the vertical position of the probe), input power, height of the liquid from the bottom, horizontal position of the probe, and thickness of bottom plate The sonochemical oxidation reactions were investigated both quantitatively and qualitatively using calorimetry, KI dosimetry, and luminol (Sonochemiluminescence, SCL) techniques. The sonochemical activity was very positively affected by the vertical boundaries. The highest sonochemical activity was obtained when the probe was placed close to the bottom of the vessel (immersion depth of 60 mm), with a high input power (input power of 75%), and optimal liquid height condition (liquid height of 70 mm). The SCL image analysis showed that the cavitational activity zone gradually expanded around the probe body and changed into a circular shape as the experimental conditions were optimized, and consequently the sonochemical activity increased. The formation of a large bright circular-shaped activity zone could be attributed to the strong reflections of the ultrasound firstly, at the vessel bottom and secondly, at the liquid surface. On the other hand, the cavitational activity zone and the sonochemical activity were negatively affected by the horizontal boundaries when the probe was placed close to the side wall of the vessel. In addition, it was found that the sonochemical activity was also significantly affected by the thickness of the support plate owing to the reflection and transmission of the ultrasound at the boundary between the liquid and the solid media.
使用 20 kHz 探头式超声处理器，在 500 mL 容器中向下辐射，从几何和操作因素方面优化了声化学活性的增强。这些因素包括探头浸入深度（探头的垂直位置）、输入功率、距底部的液体高度、探头的水平位置和底板的厚度。使用量热法、KI 剂量法和鲁米诺（声化学发光，SCL）技术对声化学氧化反应进行了定量和定性研究。声化学活性受到垂直边界的极大影响。当探头靠近容器底部（浸入深度 60 mm）、输入功率高（输入功率为 75%）且液体高度最佳（液体高度为 70 mm）时，可获得最高的声化学活性。SCL 图像分析表明，随着实验条件的优化，空化活性区逐渐在探头体周围扩展，并变成圆形，因此声化学活性增加。大而明亮的圆形活性区的形成可归因于首先在容器底部，其次在液体表面，对超声波的强烈反射。另一方面，当探头靠近容器侧壁时，空化活性区和声化学活性受到水平边界的负面影响。此外，还发现由于液体和固体介质之间边界处的超声反射和透射，声化学活性也受到支撑板厚度的显著影响。
