Adsorption-Desorption Studies of Selected Chlorophenols and Herbicides and Metal Release in Soil Mixtures with Fly Ash

Raunaq

Journal of Environmental Science and Health, Part B

2013

Metribuzin, a triazine herbicide, is poorly sorbed in the soils, therefore leaches to lower soil profile. Fly ash amendment, which enhanced metribuzin sorption in soils, may play a significant role in reducing the downward mobility of herbicide. Therefore, the present study reports the effect of Inderprastha fly ash amendment on metribuzin leaching in three soil types. Fly ash was amended at 1, 2 and 5% levels in the upper 15 cm of 30 cm long packed soil columns. Results suggested a significant reduction in the leaching losses of metribuzin in fly ash-amended columns of all the three soil types and effect increased with increase in the level of fly ash. Even after percolating water equivalent to 362 mm rainfall no metribuzin was recovered in the leachate of 5% fly ash-amended columns. Fly ash application affected both metribuzin breakthrough time and its maximum concentration in the leachate. Further, it resulted in greater retention of metribuzin in the application zone and better effect was observed in the organic carbon poor soils.

Section: Introductionmentioning

confidence: 99%

Reduced downward mobility of metribuzin in fly ash-amended soils

Raunaq

Journal of Environmental Science and Health, Part B

2013

Journal of Environmental Science and Health, Part B

“…The removal and disposal of pesticides and other chemicals are still one of the important problems concerning enviromental protection today since a large number of people are exposed to the harmful effects of pesticides in waste and potable water (Gomaa and Faust, 1974;Kennedy, 1978;Albanis et al, 1998;Crosby, 1981;Boyd 1982). …”

Section: Removal Of 2 4-d From Aqueous Solution By the Adsorbents Frmentioning

confidence: 99%

Removal of 2, 4‐D from aqueous solution by the adsorbents from spent bleaching earth

Mahramanlıoğlu

Kizilçikli

et al. 2000

The removal of 2,4-D (2,4-dichlorophenoxyacetic acid) from aqueous solutions by activated spent bleaching earths (SBE) was studied at 20 degrees C. Experiments were performed as a function of time, initial concentration, dose and particle size of the adsorbent. The Langmuir and Freundlich adsorption equations were fitted by the adsorption data obtained. The values of Langmuir and Freundlich constants were determined. The adsorption kinetic was found to follow Lagergren equation. Both the boundary layer and intraparticle diffusion played important roles in the adsorption rate of 2,4-D. As the size of the adsorbent increased, the time to reach equilibrium increased but adsorption capacity decreased.

“…Chlorophenols may also be formed as metabolites of chlorinated phenoxy acid herbicides (Davi and Gnudi 1999), or as products of the chlorination of drinking water (Michlowicz et al 2011), and are considered to be toxic and carcinogenic pollutants (Guo and Lee 2012) as they have low biodegradability and cause widespread contamination of soils, surface, and ground waters (Albanis, Danis, and Kourgia 1998;Oturan, Panizza, and Oturan 2009). Thus, the United States Environmental Protection Agency and the European Union have included chlorophenols into their list of priority pollutants (Keith 1991;Coquery et al 2005 concentration is 0.5 μg L 1 and the permissible concentration limit for each individual phenol is 0.1 μg L 1 (Quintana and Ramos 2008).…”

Section: Introductionmentioning

confidence: 98%

Determination of Chlorophenols in Wastewater with Methyl Chloroformate Derivatization, Solid Phase Extraction, and Gas Chromatography–Mass Spectrometry

2015

The determination of chlorophenols in wastewater with methyl chloroformate derivatization, solid phase extraction, and gas chromatography -mass spectrometry is reported. In order to employ this combined solid phase derivative extraction method, quantitative extraction was performed by the introduction of 100 mL of sample in 1.0 mol L 1 sodium hydroxide into a Downloaded by [University of Leeds] at 00:37 06 July 2015 2 column containing 500 mg of packed resin at a flow rate of 1.0 mL/min. The chlorophenols were retained and derivatized quantitatively in the column by the introduction of 0.25 mL of methyl chloroformate. The derivatized analytes were eluted with 5.0 mL of hexane before the effluent was dried under a stream of nitrogen. The dried solution was diluted to a volume of 50 µL with hexane followed by analysis by gas chromatography -mass spectrometry. The preconcentration parameters were optimized and under these conditions, limits of detection from 0.010 to 0.423 µg L 1 , a preconcentration factor of 2500, and precision values from 4.8 to 7.7% as the relative standard deviation were obtained. The method was employed for the analysis of water samples and the recoveries of the analytes were between 76 and 103%.