介质阻挡放电低温等离子体降解甲基红模拟染料废水的研究

Study on degradation of methyl red dye wastewater by dielectric barrier discharge low temperature plasma

利用介质阻挡放电低温等离子体技术对甲基红模拟染料废水进行降解研究,降解反应在同心管式反应器中进行。考察了放电功率、溶液初始浓度、初始pH、处理时间、气氛条件等单因素的改变对甲基红降解效果的影响,通过测定甲基红521 nm处的吸光度值、溶液pH及颜色变化,分析了甲基红降解历程,并推测了降解机理。研究结果表明:在本实验中,溶液在115 W低放电功率下的处理效果更好,由于处理效果受温度、湿度等影响,放电功率与处理效果间并不呈正相关关系;溶液的初始浓度越高,达到同样的降解效果所需的时间越长;相同条件下,模拟废水的初始pH越低,其处理后的降解效果越好,即酸性条件下更有利于甲基红断键降解。

The degradation of simulated methyl red dye wastewater in a concentric tubular reactor using dielectric barrier discharge low-temperature plasma technology was studied.The effects of discharge power,initial solution concentration,initial pH,treatment time,and atmospheric conditions on the degradation efficiency were studied.The color,pH,and absorbance of methyl red at 521 nm were used to detect the dye concentration,analyze the degradation process,and propose a degradation mechanism for methyl red.The results indicate that(1)in this experiment,the discharge power affects the degradation of methyl red but is limited by temperature and humidity,such that there is no positive correlation between the discharge power and the treatment effect.Therefore,the treatment of the solution at a low discharge power of 115 W is preferable;(2)the higher the initial concentration,the longer the time needed to achieve the same degradation rate as that achieved at lower concentrations;and(3)under the same conditions,a low pH is conducive to the degradation of methyl red,and acidic conditions are conducive to the bond breaking of methyl red.