| Summary: | 博士 === 淡江大學 === 水資源及環境工程學系 === 87 === Drainage sediment and soil contaminated with 60Co and 137Cs radionuclides were characterized and extracted by reagents in order to collect information for further volume reduction study. The fractional results indicated that 137Cs were predominantly associated with the residue, Fe-Mn oxides and organic fractions of three kinds of samples. 60Co presented different fractions distribution depending on the Mn content of samples. Sediment (A) has a significant distribution ratio (65%) in Fe-Mn oxides due to high Mn content. For other two samples, contaminant was associated with exchangable, Fe-Mn oxides, organic, and residue fractions. The extractants of NaCl and H3PO4 have high and equivalent capability for 60Co and 137Cs removal. However, the effectiveness of NaCl is not identity to all samples, high efficiency only for sediment (A). A 10% H3PO4 not only has the same leaching capability for nuclides but also for all tested samples, the average removal efficiency was up to 60% after extraction three times.
Three extraction techniques of microwave heating, water-bath shaking, and column washing were employed and their performance were proved as identity. In this study microwave technique was utilized frequently because of the advantages of easy operation and time saving.
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