研究了UV/H2O2工艺对2,4-二氯酚(2,4-DCP)的去除效果和水中阴离子、腐殖酸对该工艺降解2,4-DCP的影响。结果表明:UV/H202工艺可以有效地去除水中2,4-DCP,光降解过程符合一级反应动力学模型;在HzOz投加量为8mg/L、1个30w低压汞灯照射下,2,4-DCP在蒸馏水和自来水中反应速率常数分别为0.0232、0.0162min^-1N0f、C1^-、HCO^-3对2,4-DCP光降解有抑制作用,当3种阴离子摩尔浓度为0.5、10.0、20.0mmol/L时,对2,4-DCP光降解的抑制程度为HCO^-3〉NO^-3〉C1^-;腐殖酸在低浓度时,促进光降解反应进行,在高浓度时,2,4-DCP的光降解受到抑制。自来水中的反应速率常数低于蒸馏水中的反应速率常数是由于水中多种阴离子和腐殖酸影响的结果。
Experiments were carried out to study the effects of anions and humic acid on the UV/H2O2 oxidation of 2,4-DCP in a hatch reactor. The 2,4-DCP photodegradation data were well represented by the first:order reaction kinetics model. Using a 30 W low pressure mercury vapor discharge lamp and 8 mg/L of H2O2, the first-order rate constant was 0. 023 2 min^-1 and 0. 016 2 min^-1 , respectively, for the reaction taking place in distilled water and tapwater. The presence of one or more anions NO^-3 , C1^- , HCO^-3 inhibited 2,4-DCP photodegradation; when their concentrations were 0.5 mmol/L, 10.0 mmol/L, 20.0 mmol/L, the order of the inhibitory effect was HCO^-3 〉NO^-3 〉C1^-. The presence of humic acid at a low/high concentration enhanced/inhibited the photodegradation. The combined effects of anions and humic acid in tap water resulted in a lower photodegradation rate than that measured in distilled water.