Saltar al contenido
Merck

Mechanism for enhanced degradation of clofibric acid in aqueous by catalytic ozonation over MnOx/SBA-15.

Journal of hazardous materials (2015-01-16)
Qiangqiang Sun, Yu Wang, Laisheng Li, Jishuai Bing, Yingxin Wang, Huihua Yan
RESUMEN

Comparative experiments were conducted to investigate the catalytic ability of MnO(x)/SBA-15 for the ozonation of clofibric acid (CA) and its reaction mechanism. Compared with ozonation alone, the degradation of CA was barely enhanced, while the removal of TOC was significantly improved by catalytic ozonation (O3/MnO(x)/SBA-15). Adsorption of CA and its intermediates by MnO(x)/SBA-15 was proved unimportant in O3/MnO(x)/SBA-15 due to the insignificant adsorption of CA and little TOC variation after ceasing ozone in stopped-flow experiment. The more remarkably inhibition effect of sodium bisulfite (NaHSO3) on the removal of TOC in catalytic ozonation than in ozonation alone elucidated that MnO(x)/SBA-15 facilitated the generation of hydroxyl radicals (OH), which was further verified by electron spin-resonance spectroscopy (ESR). Highly dispersed MnO(x) on SBA-15 were believed to be the main active component in MnO(x)/SBA-15. Some intermediates were indentified and different degradation routes of CA were proposed in both ozonation alone and catalytic ozonation. The amounts of small molecular carboxylic acids (i.e., formic acid (FA), acetic acid (AA) and oxalic acid (OA)) generated in catalytic ozonation were lower than in ozonation alone, resulting from the generation of more OH.

MATERIALES
Referencia del producto
Marca
Descripción del producto

Sigma-Aldrich
Acetonitrilo, suitable for HPLC, gradient grade, ≥99.9%
Sigma-Aldrich
Metanol, suitable for HPLC, ≥99.9%
Sigma-Aldrich
Metanol, ACS reagent, ≥99.8%
Sigma-Aldrich
Acetonitrilo, HPLC Plus, ≥99.9%
Sigma-Aldrich
Metanol, suitable for HPLC, gradient grade, ≥99.9%
Sigma-Aldrich
Metanol, HPLC Plus, ≥99.9%
Sigma-Aldrich
Acetonitrilo, ACS reagent, ≥99.5%
Sigma-Aldrich
Acetonitrilo, for HPLC, for UV, ≥99.9% (GC)
Sigma-Aldrich
Acetonitrilo, suitable for HPLC, gradient grade, ≥99.9%
Sigma-Aldrich
Metanol, suitable for HPLC, gradient grade, suitable as ACS-grade LC reagent, ≥99.9%
Sigma-Aldrich
Metanol, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., ≥99.8% (GC)
Sigma-Aldrich
Metanol, Laboratory Reagent, ≥99.6%
Sigma-Aldrich
Acetonitrilo, anhydrous, 99.8%
Sigma-Aldrich
Metanol, Absolute - Acetone free
Sigma-Aldrich
Metanol, ACS spectrophotometric grade, ≥99.9%
Sigma-Aldrich
Metanol, BioReagent, ≥99.93%
Sigma-Aldrich
Acetonitrilo, suitable for HPLC-GC, ≥99.8% (GC)
Sigma-Aldrich
Metanol, ACS reagent, ≥99.8%
USP
Metanol, United States Pharmacopeia (USP) Reference Standard
Sigma-Aldrich
Acetonitrilo, biotech. grade, ≥99.93%
Sigma-Aldrich
Manganese(II) acetate tetrahydrate, ≥99%
Sigma-Aldrich
Metanol, anhydrous, 99.8%
Sigma-Aldrich
Manganese, powder, ≥99.9% trace metals basis
Sigma-Aldrich
Metanol, ACS reagent, ≥99.8%
Sigma-Aldrich
Manganese(II) acetate tetrahydrate, purum p.a., ≥99.0% (KT)
Sigma-Aldrich
Acetonitrilo, suitable for DNA synthesis, ≥99.9% (GC)
Sigma-Aldrich
Acetonitrilo, ReagentPlus®, 99%
Sigma-Aldrich
Acetonitrilo, electronic grade, 99.999% trace metals basis
Sigma-Aldrich
Metanol, puriss., meets analytical specification of Ph Eur, ≥99.7% (GC)
Sigma-Aldrich
Manganese, powder, −325 mesh, ≥99% trace metals basis