超声波/铁-炭微电解协同降解苯酚

采用超声波/铁-炭微电解联用体系,以苯酚为目标污染物,考察了苯酚溶液初始pH值、初始浓度、铁屑与活性炭投加量等因素对联用体系降解苯酚效果的影响.结果表明:考察范围内,苯酚降解率随其初始浓度和溶液初始pH值的增加而降低,随铁屑与活性炭投加量的增加而升高.当苯酚初始浓度由50mg·L-1增至270mg·L-1,溶液初始pH值由3.0增至9.0时,降解率分别由91.3%和78.4%降至34.7%和50.7%;铁屑投加量为每L苯酚溶液中40g、160g和320g,铁屑与活性炭体积比均为1∶1时,降解率依次为31.8%、51.9%和72.8%.对比实验及动力学分析表明:联用体系中超声波(US)和铁-炭微电解对苯酚降解具有明显的协同作用,协同因子Ｅ＝5.12,且降解过程符合假一级动力学规律,并根据降解速率常数随各影响因素的变化关系确定了宏观动力学模型.

Synergetic degradation of phenol by ultrasound/iron-carbon microelectrolysis

Using the ultrasound iron carbon micro electrolysis technology, the synergetic degradation of phenol was studied. The influence of initial pH, phenol concentration and the amount of iron and carbon on the phenol degradation efficiency were investigated. The results showed that the degradation rate of phenol decreased when the initial pH and phenol concentration increased, but increased when the iron and carbon dosage increased. When the initial concentration of phenol increased from 50 mg·L-1 to 270 mg·L-1, the removal rate decreased from 91.3% to 34.7%. When the pH increased from 3.0 to 9.0, the removal rate decreased from 78.4% to 50.7%. When the iron was 40 g, 160 g and 320 g in every liter phenol with the addition of equal volume of active carbon, the phenol degradation rate was 31.8%, 51.9% and 72.8%,respectively. Our results showed a significant synergetic effect of US and iron-carbon microeletrolysis on phenol degradation with a cofactor of 5.12. The degradation reaction was found to fit pseudo first order reaction kinetics, and a macro kinetic model was established according to the relationship between the degradation rate constant and each influencing factor.