In-situ dosage of Fe2+ catalyst using natural pyrite for thiamphenicol mineralization by photoelectro-Fenton process.
J Environ Manage
; 270: 110835, 2020 Sep 15.
Article
in En
| MEDLINE
| ID: mdl-32501237
The degradation of the antibiotic thiamphenicol has been studied by photoelectro-Fenton (PEF) process with UVA light using pyrite particles as catalyst source. Pyrite is a sulfide mineral that naturally acidifies the reaction medium and releases Fe2+, thus promoting the effective generation of OH from Fenton's reaction. The assays were made in an IrO2/air-diffusion cell, which yielded similar results to a boron-doped diamond (BDD)/air-diffusion one at a lower cost. In dark conditions, electro-Fenton (EF) process showed an analogous ability for drug removal, but mineralization was much poorer because of the large persistence of highly stable by-products. Their photolysis explained the higher performance of PEF. Conventional homogeneous PEF directly using dissolved Fe2+ exhibited a lower mineralization power. This suggests the occurrence of heterogeneous Fenton's reaction over the pyrite surface. The effect of current density and drug content on pyrite-catalyzed PEF performance was examined. The drug heteroatoms were gradually converted into SO42-, Cl- and NO3- ions. Nine aromatic derivatives and two dichloroaliphatic amines were identified by GC-MS, and five short-chain carboxylic acids were detected by ion-exclusion HPLC. A reaction route for thiamphenicol mineralization by PEF process with continuous H2O2 and Fe2+ supply on site is proposed.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Thiamphenicol
/
Water Pollutants, Chemical
Language:
En
Journal:
J Environ Manage
Year:
2020
Document type:
Article
Affiliation country:
Chile
Country of publication:
United kingdom