Experimental assessment of a process for the remediation of organophosphorous pesticides contaminated soils through in situ soil flushing and hydrolysis

This paper presents a treatability study for the remediation of soils contaminated with phosalone. Experimental tests were performed on an artificially contaminated standard soil with medium organic content. Phosalone was removed from the contaminated soil by flushing with an aqueous solution of ethanol. Ethanol concentration was in the range between 5 and 10% vol. Pollutant extraction efficiency, ethanol loss in soil and soil erosion were determined to assess the optimal extraction conditions. The extraction solution was then submitted to an hydrolysis treatment in order to remove phosalone. The degradation kinetic of phosalone during hydrolysis in presence of ethanol was investigated. Experimental tests were performed at several pH and temperature conditions and kinetic constant rate were determined. In addition, the effect of temperature on half-life time and activation energy of hydrolysis reaction was examined.