Laboratory study of solvent extraction of polychlorinated biphenyls in soil

• Main Author: Valentin, Melissa McShea.
• Other Authors: Prasher, Shiv O. (advisor)
• Format: Others
• Language: en
• Published: McGill University 2000
• Subjects: Polychlorinated biphenyls > Environmental aspects.; Soil remediation.; Solvent extraction.
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31553

Polychlorinated biphenyls (PCBs) are toxic, stable organic contaminants that are present in air, water, soil, plants and animals all around the world. The market for PCB treatment technologies is estimated to be $300 to $600 million (Canadian dollars) for the year 2000, and will expand in future years. Existing treatment technologies to remove PCBs from soil are underutilized because they are more expensive than landfilling and incineration. This thesis presents a laboratory study of an innovative PCB remediation process that will extract PCBs from soil in-situ for subsequent destruction above ground. This remedy will remove PCBs from surficial soil without the need for excavation. Two laboratory studies were conducted on field-contaminated soil. The first experiment evaluated the effectiveness of hexane, methyl isobutyl ketone, and ethyl acetate in removing PCBs from soil. Ethyl acetate and MIBK were equally effective, removing 99% and 98% of PCBs from dry soil in 4 days, respectively. In the second experiment, soil was exposed to ethyl acetate for varying amounts of time, and some of the samples were treated a second time with fresh solvent. PCB removal increased as treatment time was increased from 10 minutes to 50, 250, and 1250 minutes, but the rate of PCB removal decreased as treatment time increased. The second 10-minute extraction removed an additional 1--10% of the remaining PCBs.