Removal of Aroclor 1016 from contaminated soil by Solvent Extraction Soil Agglomeration Process

Abstract

This communication reports the results of a study to assess the suitability of the National Research Council of Canada's Solvent Extraction Soil Remediation (SESR) process to effectively remediate soils contaminated with PCBs. A series of small-scale batch extraction tests were carried out using a loamy clay soil sample spiked with Aroclor 1016. The variables examined included the effects of solvent type, water addition, agglomerate size, and extraction additives. Aroclor 1016 recovery rates for the SESR process were higher than those found for high shear agitation of soil slurries without agglomeration and Soxhlet extraction (93.9 ± 1.9, 90.6 ± 1.5 and 82.7 ± 0.9% respectively). A two-stage extraction process, with a series of three wash steps incorporated into the solid–liquid separation operation, produced a treated soil with an average Aroclor 1016 concentration of 49 ± 8 mg/kg on a dry weight basis (95.4 ± 2.4% removed). Key words: PCBs, soil remediation, agglomeration, solvent extraction.