Fenton's Reagent Treatment Research Articles

Application of Fenton's Reagent and Activated Carbon for Removal of Nitrification Inhibitors

The subject of this treatability study was groundwater polluted with ammonia (up to 300 mg l−1) and a number of organic contaminants known to be inhibitors of nitrification. During this study two treatment methods for nitrification inhibitors removal, activated carbon adsorption and Fenton's reagent, were tested. The efficiency of inhibitors removal was monitored using respirometry, bench-scale treatment system and chemical analyses (COD, TOC, GC/MS). Activated carbon adsorption and Fenton's reagent treatment were equally effective in removal of organic inhibitors of nitrification. The oxygen uptake and the rate of nitrification was found to be higher for the groundwater treated with Fenton's reagent compared to the groundwater treated with activated carbon, providing the same removal of TOC and COD by each treatment.

Integrating chemical and biological remediation of atrazine and S‐triazine‐containing pesticide wastes

AbstractFenton's reagent (FR) and the catabolic activity of Rhodococcus corallinus and Pseudomonas sp. strain D were combined to detoxify s‐triazines in pure solutions and mixed wastes. In solutions containing only atrazine, complete atrazine decomposition was accomplished with 2.69 mM FR. But FR treatment was not complete in a remediation context because stable, potentially carcinogenic chlorinated products accumulated as end products. Rhodococcus corallinus degraded these products in ≤10 min and produced 47% 14CO2 from [2,4,6‐14C]atrazine in 7 d. Combining R. corallinus with Pseudomonas sp. strain D increased 14CO2 production to 73%. When applied to a pesticide rinse water containing atrazine, cyanazine, alachlor, metolachlor, and EPTC, ≥99% of the pesticides were degraded with 12.2 mM FR. Subsequent treatment with R. corallinus and Pseudomonas sp. strain D degraded all chlorinated s‐triazine intermediates and released 70% 14CO2 from a [2,4,6‐14C]atrazine tracer in 10 d. Use of R. corallinus obviated the need for additional chemical pretreatment, e.g., acidification or base hydrolysis, used in previous studies prior to microbial incubations. Thus, this method has potential as an on‐site treatment for pesticide rinse water.

Chemical Oxidation Technologies: Ultraviolet Light/Hydrogen Peroxide, Fenton's Reagent, and Titanium Dioxide-Assisted Photocatalysis

The application status and potential of three chemical oxidation treatment methods which generate powerful oxidants (hydroxyl radicals): ultraviolet light (UV)/hydrogen peroxide (H2O2) process, Fenton's reagent treatment, and titanium dioxide (TiO2)-assisted photocatalytic degradation, are described and discussed. These oxidation methods are known to effectively degrade and, in several cases, mineralize contaminants ranging from inorganic compounds (such as cyanides) to chlorinated aliphatic compounds and complex aromatic compounds in reaction times on the order of a few minutes to a few hours. Of the three oxidation systems discussed, the technology for the UV/H2O2 process is the most advanced, with numerous successful full-scale treatment units already in existence. Applications of both the Fenton's reagent and TiO2-assisted photodegradation processes are currently being developed, with the concepts proven in numerous laboratory-scale studies for a wide range of contaminants. However, both of these processes have only been studied at the pilot/field scale to a limited extent. The application of Fenton's reagent as a pretreatment step prior to biological treatment for industrial wastes and contaminated soils appears promising. Improved system configuration and quantum efficiency of photoreactors are likely to improve the economics of TiO2-assisted photodegradation for groundwater treatment, especially with the use of solar illumination.