EDTA enhanced pre-magnetized Fe0/H2O2 process for removing sulfamethazine at neutral pH

Ethylenediaminetetraacetic acid (EDTA) was used to enhance pre-magnetized Fe 0 /H 2 O 2 process for sulfamethazine (SMT) removal at neutral pH. Only 19.4% SMT was removed in pre-Fe 0 /H 2 O 2 within 60 min at neutral pH while 90.6% SMT was removed after addition of 0.1 mM EDTA. Meanwhile, k (10 3 ) value for SMT removal in pre-Fe 0 -EDTA/H 2 O 2 was 1.3 folds larger than in Fe 0 -EDTA/H 2 O 2 . Single-factor experiments and response surface methodology (RSM) were used to optimize the system for SMT removal. Maximum k (10 3 ) value was 81.4 min −1 obtainning at conditions of Fe 0 0.28 g L −1 , EDTA 0.13 mM, and H 2 O 2 36.2 μM. The presence of EDTA and magnetization could inhibit the generation of iron oxides , reduce the contact angle of Fe 0 , and improve the recovery of surface Fe II which induced a faster catalytic decomposition of H 2 O 2 . The system could still achieve good performance for removing SMT after six consecutive reaction cycles. These results demonstrated that pre-Fe 0 -EDTA/H 2 O 2 system has the potential application for wastewater treatment .