Fenton Oxidation of DMF Wastewater and Influence of Inorganic Ions on Reaction

N,N-Dimethylformamide (DMF) is a universal organic solvent in industry,while it is toxic and non-biodegradable.In this paper,Fenton oxidation was used to treat model DMF wastewater and the influence of pH,reaction time,dose of oxidation agent,as well as the effect of inorganic anions Cl^- and SO₄^2- were investigated.The experimental results showed that the optimum conditions with effluent COD<100 mg/L were as follows:when the concentration of DMF was 1 g/L,the dosage of 30% H₂O₂ was 40 mL/L,pH=2.0,n(H₂O₂):n(Fe²⁺)=3:1,reacting time is 2.5 h.Meanwhile,Cl^- had a strong inhibition effect on Fenton oxidation:the COD of effluent increased from 90 mg/L to 250 mg/L with 1 g/L Cl^-.The effect of SO₄^2- on the reaction was very small:with a concentration higher than 10 g/L,it could accelerate the reaction to some extent.