4.8 Article

Photo-assisted reductive cleavage and catalytic hydrolysis-mediated persulfate activation by mixed redox-couple-involved CuFeS2 for efficient trichloroethylene oxidation in groundwater

Journal

WATER RESEARCH
Volume 222, Issue -, Pages -

Publisher

PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.watres.2022.118885

Keywords

Chlorinated organic contaminants; Groundwater remediation; CuFeS2 activator; Persulfate; Hydroxyl radical; Advanced oxidation process

Funding

  1. National Key Research and Development Program of China [2021YFA1202500]
  2. Natural Science Funds for Distinguished Young Scholar of Guangdong Province, China [2020B151502094]
  3. Guangdong Basic and Applied Basic Research Foundation [2020A1515110723]
  4. Shenzhen Basic Research Foundation [K21295002]
  5. National Natural Science Foundation of China [21777045]
  6. Foundation of Shenzhen Science and Technology Innovation Commission [JCYJ20200109141625078]
  7. Special Funds for the Cultivation of Guangdong College Students' Scientific and Technological Innovation [pdjh2021c0031]

Ask authors/readers for more resources

Activation of persulfate by mixed redox-couple-involved chalcopyrite nanoparticles can decompose refractory organic compounds. The Cu(I)/Fe(III) redox couple in chalcopyrite plays a crucial role in this process.
Persulfate (PS, S2O82-) activation through transition metal sulfides (TMS) has gained increasing attention since it can decompose a wide variety of refractory halogenated organic compounds in groundwater and wastewater. However, the processes of PS activation by TMS and particularly the formation of center dot OH radical under anoxic and acidic conditions (pH similar to 2.8) remain elusive. Herein, by employing mixed redox-couple-involved chalcopyrite (CuFeS2) (150 mg/L) nanoparticles for PS (3.0 mM) activation, 96% of trichloroethylene was degraded within 120 min at pH 6.8 under visible light irradiation. The combination of experimental studies and theoretical calculations suggested that the Cu(I)/Fe(III) mixed redox-couple in CuFeS2 plays a crucial role to activate PS. Cu (I) acted as an electron donor to transfer electron to Fe(III), then Fe(III) served as an electron transfer bridge as well as a catalytic center to further donate this received electron to the O-O bond of PS, thus yielding SO4 center dot- for trichloroethylene oxidation. Moreover, for the first time, center dot OH radicals were found to form from the catalytic hydrolysis of PS onto CuFeS2 surface, where S2O82- anion was hydrolyzed to yield H2O2 and these ensuing H2O2 were further transformed into center dot OH radicals via photoelectron-assisted O-O bond cleavage step. Our findings offer valuable insights for understanding the mechanisms of PS activation by redox-couple-involved TMS, which could promote the design of effective activators toward PS decomposition for environmental remediation.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.8
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available