真空紫外光降解五氯酚钠以及过硫酸盐对反应的促进作用

研究了真空紫外光(VUV,185 am)对于水溶液中五氯酚钠的降解,反应2 h后,初始浓度为10 mg/L的五氯酚钠的去除率达到99%以上,有机氯的脱除率达到70%以上,有效地实现了五氯酚钠的脱毒.溶液初始pH值对五氯酚钠的真空紫外光解有很大影响,pH=10.9时的降解速率常数是pH=3.1时的3倍.表观一级反应速率常数随初始浓度的增加而线性下降.在反应溶液中加入过硫酸盐,可有效提高五氯酚钠的真空紫外光降解速率和矿化速率,过硫酸盐和五氯酚钠摩尔比为24时,降解速率提高3倍,反应4 h后TOC去除率达到95%.

Photodegradation of sodium pentachlorophenate by VUV and enhancement by peroxydisulphate

The photodegradation of sodium pentachlorophenate (PCP-Na) under illumination of the vacuum ultraviolet light (VUV, 185nm) was investigated. After 2h reaction,PCP-Na with initial concentration of 10 mg/L was degraded more than 99%,and dechlorination was up to 70%. The VUV photodegradation of PCP-Na was greatly dependent on initial pH value of the solution. The degradation rate constant at pH 10.9 was 3 times as that at pH 3.1. Moreover, the apparent first order reaction rate constant linearly decreased with increase of initial PCP-Na concentration. The addition of peroxydisulphate effectively improved the degradation rate and mineralization of PCP-Na by VUV photodegradation. When the mole ratio of peroxydisulphate and PCP-Na was 24, the reaction rate constant was increased 3 times,and TOC removal was up to 95% after 4 h reaction.