Japan Geoscience Union Meeting 2018

Presentation information

[EE] Poster

A (Atmospheric and Hydrospheric Sciences) » A-GE Geological & Soil Environment

[A-GE30] Energy-Environment-Water Nexus and Sustainable Development

Mon. May 21, 2018 3:30 PM - 5:00 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Ming Zhang(Institute for Geo-Resources and Environment, Geological Survey of Japan, AIST), Ken Kawamoto(Graduate School of Science and Engineering, Saitama University), Xue Qiang(中国科学院武漢岩土力学研究所, 共同), Jet-Chau Wen(National Yunlin University)

[AGE30-P04] Minimizing the interference of carbonate ions on degradation of SRF3B dye by Fe0-aggregate-activated persulfate process

Na Liu2, Feng Ding3, Chih-Huang Weng3, Chi-Chin Hwang4, *Yao-Tung Lin1 (1.National Chung Hsing University, 2.Jilin University, 3.I-Shou University, 4.National University of Tainan)

Keywords:Carbonate ions, Dye, Persulfate, Ultrasound, Zero-valent iron aggregates

Carbonate ions in wastewater can interfere with the reactions in advanced oxidation processes. In the present study, the effects of carbonate ions on the degradation of a polyazo direct dye, the Sirius® Red F3B (SRF3B), using persulfate (PS) oxidation catalyzed by Fe0 aggregates (PS/Fe0) was investigated. Results of this study indicated that the oxidation power of the PS/Fe0 process was inhibited in the dye solutions containing carbonates, and the efficiency of SRF3B decolorization decreased with increasing concentration of Na2CO3. A short period of ultrasound (US) irradiation can significantly enhance the destruction of dye molecules. Complete decolorization of a 25 mg/L SRF3B solution containing 1×10-3 M carbonate, 5×10-3 M PS, and 1.5 g/L Fe0 was achieved within 5 min in a PS/Fe0/US system augmented with 5 min of US irradiation (60 kHz, 106 W/cm2). The operating cost to complete removal of the dye was estimated at 2.79 USD/m3. Higher PS dosage and US power further minimized the interference from carbonate ions. A two-step reaction model, including a slow surface heterogeneous and a fast homogeneous aqueous reactions was proposed for the system. The presence of Fe2+ and Fe3+ ions identified using X-ray photoelectron spectroscopy, suggests a direct oxidation of the dye on the surface of the Fe0 aggregates.