Removal effectiveness and mechanisms of naphthalene and heavy metals from artificially contaminated soil by iron chelate-activated persulfate

► FeEDTA/FeEDDS-activated persulfate oxidation removed PAH & heavy metal from soil. ► More naphthalene was removed by FeEDTA-activated persulfate compared to FeEDDS. ► Persulfate was consumed to oxidize EDDS in FeEDDS-activated persulfate oxidation. ► Metals can be extracted from soil by free EDTA/EDDS dissociated from FeEDTA/FeEDDS. ► Naphthalene oxidation can be induced by e− transfer among Fe2+, DOM & naphthalene.