Degradation of tris(2-chloroethyl) phosphate (TCEP) in aqueous solution by using pyrite activating persulfate to produce radicals

Wenjie Lian; Xiaoyun Yi; Kaibo Huang; Ting Tang; Rui Wang; Xueqin Tao; Zeli Zheng; Zhi Dang; Hua Yin; Guining Lu

doi:10.1016/j.ecoenv.2019.03.027

Degradation of tris(2-chloroethyl) phosphate (TCEP) in aqueous solution by using pyrite activating persulfate to produce radicals

Ecotoxicol Environ Saf. 2019 Jun 15:174:667-674. doi: 10.1016/j.ecoenv.2019.03.027. Epub 2019 Mar 13.

Authors

Wenjie Lian¹, Xiaoyun Yi², Kaibo Huang¹, Ting Tang¹, Rui Wang¹, Xueqin Tao³, Zeli Zheng³, Zhi Dang⁴, Hua Yin⁴, Guining Lu⁵

Affiliations

¹ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
² School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China. Electronic address: xyyi@scut.edu.cn.
³ College of Environmental Science and Engineering, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.
⁴ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China.
⁵ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China. Electronic address: lutao@scut.edu.cn.

PMID: 30875560
DOI: 10.1016/j.ecoenv.2019.03.027

Abstract

Organophosphorus esters (OPEs), as one kind of emerging and toxic contaminant are ubiquitous in various environments. This study investigated the degradation of tris(2-chloroethyl) phosphate (TCEP) as a category OPEs by pyrite (FeS₂)-activated persulfate (PS). The result shows that near-100% degradation of TCEP was achieved after 120 min in FeS₂-PS system. The important role of Fe²⁺ in the activation mechanism was confirmed by the introduction of Fe²⁺ into the PS only system. Radical scavengers experiment and electron paramagnetic resonance (EPR) confirmed the presence of SO₄^·- and ·OH，which revealed that ·OH and SO₄^·- played major roles in TCEP degradation. The effect of various environmental factors, including pyrite and oxidant dosage, inorganic ions and pH were investigated. The result indicated that Fe³⁺ and Cl^- can accelerate the degradation rate of TCEP and the reaction between TCEP and FeS₂-PS favors acidic conditions (pH>9). In addition, due to the acidification of pyrite, this system can be applied with a wide pH range. Besides, two oxidation products, C₄H₉Cl₂O₄P and C₂H₆ClO₄P were identified, which suggest that hydroxylation was probably the main mechanism. This study greatly improves our understanding on TCEP removal in FeS₂-PS system.

Keywords: Product identification; Pyrite-persulfate; Radicals; Tris(2-chloroaniline) phosphate.

MeSH terms

Hydroxylation
Iron / chemistry*
Oxidation-Reduction
Phosphines / chemistry*
Phosphines / isolation & purification
Sulfates / chemistry*
Sulfides / chemistry*
Waste Disposal, Fluid / methods*
Water / chemistry
Water Pollutants, Chemical / chemistry*
Water Purification

Substances

Phosphines
Sulfates
Sulfides
Water Pollutants, Chemical
Water
pyrite
tris(2-carboxyethyl)phosphine
Iron