Effects of Nanoscale Zero-Valent Iron on Soil-Leaching of Trinitrotoluene Contaminated Soil in Acid Rain Conditions

Abstract

The study of effects of nanoscale zero-valent iron (nZVI) on soil-leaching of trinitrotoluene (TNT) contaminated soil in the acid rain conditions is aim to the determination of the effect of nZVI which used as treatment material on soil leaching of TNT contaminated soil in raining condition. Research methodology, soil leaching batch reactor was designed for TNT remediation in soil with nZVI. The reactor was divided into three compartments for the different series of the experiment. Three compartments of the experiments were used for 1) TNT-contaminated soil column (without leaching), 2) TNT-contaminated soil was leached with rainwater, and 3) TNT-contaminated soil was mixed with nZVI and leached with rainwater. The leachants in the experiment were distilled water (pH 6-6.5) and artificial rainwater (pH≈5). The results of this study found the highest TNT removal efficiency was obtained from in the leaching column with nZVI, followed by the leaching column without nanoparticles and non-leaching column at 100.00, 37.25, and 10.65 % respectively. The leachant (artificial rain) which was slightly acidic in pH could remove some of TNT. The leachant improved solubility and transformation of nitro group in TNT to amino group by H ions addition. The results of the current study can be used to predict the circumstances of leaching TNT on-site in the rainy season.