氯甲烷与偶氮染料混合废水的超声脱色

Decolorization of chloromethane and azo dyes mixed wastewater by ultrasound

使用40 kHz超声(US)脱色氯甲烷(包括CCl4、CHCl3和CH2Cl2)与偶氮染料(包括甲基橙与铬黑T)混合模拟废水,考察了氯甲烷初始浓度对偶氮染料超声脱色和TOC去除的影响。结果表明:偶氮染料的单独超声脱色速率很慢;而在CCl4与CHCl3存在时超声能使偶氮染料短时间内脱色至无色,但对其TOC的超声去除促进作用较差;CH2Cl2对偶氮染料的超声脱色促进作用很小。使用0.392 W/cm2的超声处理24 mg/L铬黑T水溶液,当CCl4和CHCl3初始浓度分别为6.22 mmol/L和8.30 mmol/L时,20 min脱色率均达到90.86%,但相应的TOC去除率只有22.72%和17.76%。同样条件下,甲基橙处理效果比铬黑T稍优。

The decolorization of azo dyes（including methyl orange and eriochrome black T） and methyl chloride（including CCl4,CHCl3 and CH2Cl2） simulated wastewaters by using 40 kHz ultrasound was studied.The effect of initial chloromethane concentration on azo dyes decolorization and TOC removal of sonication was investigated.The results showed that the ultrasonic decolorization rates of azo dyes were very slow.The ultrasound could make azo dyes to colorless in a short time in the presence of CCl4 and CHCl3,but had less effect of its TOC ultrasonic removal.The sonochemical decolorization of azo dyes was very poor in the presence of CH2Cl2.When the initial eriochrome black T concentration was 24 mg/L,the ultrasonic intensity was 0.392 W/cm^2,the initial concentration of CCl4 and CHCl3 was 6.22 mmol/L and 8.30 mmol/L,the 20 min decolorization rate reached 90.86%,but the corresponding TOC removal rate was only 22.72% and 17.76%.Under the same conditions,the treatment effect of methyl orange was slightly superior than eriochrome black T.