柠檬酸改性Fenton氧化技术对陕北石油污染土壤的修复影响研究

Research on remediation of oil contaminated soil in northern Shaanxi by citric acid modified Fenton technology

利用柠檬酸改性Fenton试剂对陕北石油污染土壤进行修复处理,考察了pH、H_2O_2、Fe SO_4·7H_2O、柠檬酸浓度对土壤中总石油烃(TPH)、土壤有机质(SOM)及H_2O_2利用率的影响。结果表明,TPH的降解效果随着H_2O_2、Fe SO_4·7H_2O、柠檬酸浓度的升高呈先升高后持平或稍有下降趋势,SOM氧化率则随pH与柠檬酸浓度的升高呈下降后持平或上升趋势,并于中性条件下,H_2O_2600 mmol/L,Fe SO_4·7H_2O 8 mmol/L,柠檬酸24 mmol/L时,处理效果达到最佳,此时,TPH降解率达33.68%,SOM氧化率4.22%;且在该条件下,可将H_2O_2对TPH降解与SOM氧化的作用比例由2.1∶1升高至4∶1。可见,该技术有利于提高H_2O_2的有效利用,降低土壤有机质的氧化。

This study attempts to restore the oil contaminated soil in northern Shaanxi by using citric acid modified Fenton reagent,with the influence of pH,H2O2,FeSO4·7H2O,citric acid concentration on soil total petroleum hydrocarbon （TPH）,soil organic matter （SOM） and H2O2 utilization being investigated.The results show that the TPH removal efficiency increases and then becomes flat or slightly downward with increased concentration of H2O2,FeSO4·7H2O and citric acid;The SOM oxidation rate efficiency decreases and then becomes flat or slightly,increasing with increased pH and citric acid concentration.Under neutral condition,when H2O2 600 mmol/L,FeSO4·7H2O 8 mmol/L and citric acid 24 mmol/L to achieve the best results;in this condition,the TPH degradation rate can reach 33.68%,and SOM oxidation rate 4.22%,with the ratio of H2O2 to TPH degradation and SOM oxidation increases from 2.1∶1 to 4∶1.It can be seen that the technology can improve the effective utilization of H2O2 and reduce the oxidation of SOM.