关键词: 超声波, SO2解吸, 添加剂, 缓冲溶液, 解吸效率

Abstract: Introducing ultrasonic wave as an external field into the process of desorbing sulfur dioxide in sodium citrate buffer solution is a new approach. In this work, based on the characteristics of ultrasonification and the solution properties, the desorption mechanism of sulfur dioxide and the influence of the additives (surfactants and inert gases) on ultrasonic desorption are investigated. Experiments are performed to verify the analytical results. The results show that lauryl sodium sulfate, sodium dodecyl benzene sulfonate and dodecyl trimethyl ammonium chloride can all significantly reduce the surface tension of sodium citrate solution, thus the desorption efficiency of sulfur dioxide can be improved. Among these three surfactants, lauryl sodium sulfate gives the best effect. However, when the surfactant concentration is over 0.1 g/L, the surface tension of citrate solution can be hardly decreased further and the desorption rate of sulfur dioxide increases very slowly. It is also found that adding inert gases in the desorption system can also increase the desorption efficiency of sulfur dioxide by as much as 20%.

Key words: ultrasonic wave, sulphur dioxide, additives, buffer solution, desorption efficiency