Study On Degradation Of DMP By Electro-Fenton Modified With EDTA

In part one(No.1～4 chapter),the treatment of dimethyl phthalate(DMP)in neutral or basic solution by electro-Fenton modified with EDTA was studied,and the characteristic of the modified electro-Fenton system was investigated.The work is listed as below;(1)The effects of pH,electrolyte concentration,O₂ flow rate and current density on the accumulation rate of H₂O₂ were discussed.It was found that the optimal condition in neutral solution for H₂O₂ accumulation was O₂ flow rate 300mL/min and I=6mA.And electrolyte concentration had no significant effect on the [H₂O₂]/t.(2)The results show that the electro-Fenton system modified with EDTA can degrade DMP under neutral or basic conditions.The reason that Fenton reaction can keep up under neutral or basic conditions is that chelating with EDTA make iron keep in the state of dissolving,which make reaction between iron and H₂O₂ more easily.(3)Under the following conditions,that is,pH=7,6mA invariable current, 0.1mmol·1^-1electrolyte Na₂SO₄,rate of O₂ current at 300mL/min,the Fe²⁺/EDTA optimum initial concentration is 0.5mmol/L when treating DMP with an initial concentration of 20mg/L,the removal efficiency of DMP is up to 98% after reacting for 3h.In part two(No.5 chapter),the treatment of dibutyl phthalate(DBP)by UV/H₂O₂ was studied,and the effect of dust on removal efficiency of DBP by UV/H₂O₂ was investigated.The results show,DBP in solution is degraded by UV/H₂O₂ rapidly and effectively,and the removal efficiency of DBP lower when dust existing.The reason is,maybe,that the solubility of DBP is too feeble,and it is adsorbed on the surface of dust very easily,which make the touch lessened between DBP and oxidant,consequently,the rate of reaction slower.