大气压垂直流动液体地电极制备等离子体活化溶液的理化特性

Physicochemical Properties of Plasma Activated Liquid Generated by an Atmospheric Pressure Vertical Falling Liquid Ground Electrode

大气压气液放电制备的等离子体活化溶液(plasma activated liquid,PAL)是一种富含多活性物种的溶液。该研究以流动水柱替换传统线筒式电极结构内的中心金属电极,设计出利用垂直流动水柱产生放电的电极结构,以实现高效制备PAL的目的。通过改变溶液(水柱)的初始电导率和施加电压,研究了利用该电极所制备PAL的理化特性及灭菌效果,计算了在不同放电参数下产生活性物种的能量效率,并讨论了该电极与液面下鼓泡法电极放电产生活性物种能量效率的差异。结果表明,随着施加电压和溶液初始电导率的增加,PAL的p H值逐渐下降,而平均电导率呈逐渐升高趋势,NO_(3)^(-)、H2O_(2)、O_(3)的浓度逐渐增大。当溶液初始电导率在2~200 mS/cm的范围内,NO_(2)^(-)的浓度随施加电压的升高呈现出先增加后降低的趋势。但当溶液初始电导率<2 m S/cm时,NO_(2)^(-)的浓度随施加电压的增加单调升高。PAL的灭菌效率随着施加电压的升高而增大。该研究将为气液放电技术在不同环境中应用选取适宜电极提供新的思路。

Plasma activated liquid(PAL)produced by atmospheric pressure gas-liquid discharge is a solution containing a variety of reactive oxygen and nitrogen species(RONS).Here,vertical falling water is used as the ground electrode to re-place the inner center electrode in a conventional wire barrel discharge device.The effects of different applied voltage and initial solution conductivity on the physicochemical properties,inactivation efficacy and energy efficiency of PAL are in-vestigated.The results show that the pH value of PAL decreases and the conductivity of PAL increases with the increase of applied voltage and initial solution conductivity.When the initial solution conductivity is 0.05~200 mS/cm,the con-centrations of NO_(3)^(-),H2O_(2) and O_(3) in the PAL increase with increasing the applied voltage and the initial solution conductivity.The NO_(2)^(-)concentration first increases and then decreases with increasing the applied voltage when the ini-tial solution conductivity is 2.0~200 mS/cm.The NO_(2)^(-)concentration increases with the increase of applied voltage at the initial solution conductivity of lower than 2 mS/cm.PAL shows inactivation efficacy on bacteria with the increase of ac-tivation time.This study provides a new idea for selecting suitable electrodes for different environmental applications of gas-liquid discharge technology.