Degradation of methyl orange by pyrite activated persulfate oxidation: mechanism, pathway and influences of water substrates
Degradation mechanism of methyl orange (MO), a typical azo dye, with pyrite (FeS2) activated persulfate (PS) was explored. The results showed that when the initial concentration of MO was 0.1 mM, FeS2 was 1.6 g/L and PS was 1.0 mM, the removal rate of MO could reach 92.9% in 150 min, and the removal...
Main Authors: | , , , , , , , , , |
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Format: | Article |
Language: | English |
Published: |
IWA Publishing
2022-05-01
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Series: | Water Science and Technology |
Subjects: | |
Online Access: | http://wst.iwaponline.com/content/85/10/2912 |
Summary: | Degradation mechanism of methyl orange (MO), a typical azo dye, with pyrite (FeS2) activated persulfate (PS) was explored. The results showed that when the initial concentration of MO was 0.1 mM, FeS2 was 1.6 g/L and PS was 1.0 mM, the removal rate of MO could reach 92.9% in 150 min, and the removal rate of total organic carbon could reach 14.1%. In addition, both pH ≤ 2 and pH ≥ 10 could have an inhibitory effect in the FeS2/PS system. Furthermore, Cl− and low concentrations of had little effect on the degradation of MO with FeS2/PS. However, and high concentrations of could inhibit the degradation of MO in the system. Besides, MO in river water and tap water were not degraded in FeS2/PS system, but acidification (pH = 4) would greatly promote the degradation. In addition, the removal rate of MO with FeS2/PS could still reach about 90% after five cycles of FeS2. Furthermore, the intermediates and possible degradation pathways were speculated by LC-MS, and the degradation mechanism of MO by FeS2/PS was that the cycle of Fe(III)/Fe(II) could continuously activate persulfate to produce . The results could provide technical support for azo dye degradation in the FeS2/PS system. HIGHLIGHTS
FeS2/PS system could effectively remove methyl orange.;
Acification (pH = 4) could promote the degradation of methyl orange in river water by a FeS2/PS system.;
FeS2 could be recycled for activation of PS.; |
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ISSN: | 0273-1223 1996-9732 |