Degradation of Phthalates in Soil by Zero-valent Iron Activated Persulfate
To explore the degradation efficiency,optimal degradation conditions and soil properties of di(2-ethylhexyl)phthalate(DEHP)by zero-valent iron(ZVI)-activated persulfate(PS),the effects of initial pH value,soil soil ratio,PS concentration,ZVI addition amount and reaction time on DEHP degradation efficiency were studied by single factor and orthogonal experiments.The effects of oxidation system on soil physicochemical properties and available nutrients were also discussed.The results showed that the influence degree of five factors on DEHP degradation rate was PS＞initial pH＞ZVI addition amount＞soil and water ratio＞reaction time.When the initial pH was 3,water/soil ratio 4:1,PS concentration was 1 mmol/g,ZVI dosage was 0.5 mmol/g and reaction time was 80 min,DEHP degradation rate was in the range of 75.12％～80％,the degradation effect was best.ZVI/PS oxidation system had a great influence on soil properties.With the increase of PS concentration,soil pH and soil organic matter content showed different degrees of decrease,and soil electrical conductivity and REDOX potential showed an increasing trend.When PS and ZVI were added at the same time,the available nitrogen con-tent increased significantly.Adding ZVI or PS to soil solution alone significantly increased the content of available phos-phorus,but when adding PS and ZVI to soil solution at the same time,the content of available phosphorus decreased sharply.When the concentration ratio of ZVI or PS was greater than or equal to 1,the content of available potassium decreases sharply,by 76％.The effect of oxidant addition on soil properties should be fully evaluated in the actual remediation of PAEs contami-nated soil.This study can provide theoretical and practical basis for the removal of DEHP in soil environmental media by ZVI-activated PS.
万方数据
维普
