120th General Meeting of the KCS

Type Poster Presentation
Area Environmental Energy
Room No. Exhibition Hall 2+3
Time 10월 19일 (목요일) 11:00~12:30
Code ENVR.P-523
Subject Heterogeneous Fenton-like degradation using NTA chelated manganese ferrite
Authors Yu-Gyeong Kang, YOON-SEOK CHANG 1,*
Division of Environmental Science and Engineering, Pohang University of Science and Technology, Korea
1Division of Environmental Engineering, Pohang University of Science and Technology, Korea
Abstract Some chelating agents can make heterogeneous Fenton reactions faster, as well as homogeneous Fenton reactions. However, the whole mechanism of the enhanced heterogeneous Fenton reactions is still unclear, due to the coexistence of homogeneous and heterogeneous reactions. In the present work, nitrilotriacetic acid (NTA) was introduced to study the role of the chelating agent in the oxidation of diclofenac in manganese ferrite (MnFe2O4) system. Ferrite has similar structure with magnetite (Fe3O4), which Fe2+ sites were substituted to other metal cations. The presence of some metals in the ferrite structure strongly increased the rate of H2O2 decomposition and the oxidation of the organic molecules. Especially, homogeneous Mn2+-mediated Fenton-like process based on Fe(III)-NTA complex that is efficient at circumneutral pH range. Kinetics experiments showed that the presence of Mn2+significantly enhanced the effectiveness of Fe(III)-NTA complex catalyzed Fenton-like reaction. The addition of NTA in solution accelerated diclofenac removal due to the induced homogeneous Fenton reaction by enhanced dissolution of Me2+ and Fe3+ cation. Effects of NTA surface loadings, initial H2O2 concentrations, initial diclofenac concentrations, calcination temperature of ferrite, and initial pH on the reaction kinetics in NTA modified ferrite/H2O2 system were investigated. Results showed that the surface complexed NTA (Me2+/Fe3+-NTA) inhibited H2O2 decomposition by competition for surface active sites, but enhanced diclofenac removal by Me2+/Fe3+-NTA was shown due to the efficient use of reactive oxygen species (ROS). Additionally, field applicability was tested in real groundwater solution, and reusability test was conducted.
E-mail ygkang74@postech.ac.kr