Remediation of soil burdened with excesses of hydrophobic organic contaminants (HOCs) and toxic trace metals (TMs)

修复含有过量疏水性有机污染物 (HOC) 和有毒微量金属 (TM) 的土壤

• 批准号: 6687-2008
• 负责人: Marshall, William
• 金额: $ 1.82万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=474142
• 关键词: Remediation; soil; burdened; excesses; hydrophobic

Within the general objective of optimizing procedures to remediate soil that has been burdened with excesses of hydrophobic organic contaminants (HOCs) and trace metals (TMs), a series of studies have been designed to maximize the efficiency of the overall process while minimizing costs. The process consists of four sequential steps. Pollutants (HOCs and TMs) are simultaneously mobilized/removed from the soil by washing with an aqueous surfactant suspension (ASS) containing complexing reagent(s). The HOC fraction is recovered by back-extraction of the ASS phase with a non-polar organic solvent (hexane) and detoxified by hydrodechlorination /reduction during contact with a noble-metal catalyst. Subsequently, the heavy metal fraction is recovered by precipition with zero-valent magnesium (Mg0) to form insoluble oxyhydroxides that are recovered by filtration. The purified ASS fraction (now devoid of both HOCs and TMs) is returned to clean more soil. With this process, both classes of toxicant are converted to toxicologically innocuous products.

在优化程序的总目标，以修复土壤，已与过量的疏水性有机污染物（HOCs）和微量金属（TM）的负担，一系列的研究已经设计，以最大限度地提高整个过程的效率，同时最大限度地降低成本。该过程由四个连续步骤组成。通过用含有络合剂的表面活性剂水悬浮液（ASS）洗涤，污染物（HOCs和TM）同时从土壤中移动/去除。HOC馏分通过用非极性有机溶剂（己烷）反萃取ASS相来回收，并在与贵金属催化剂接触期间通过加氢脱氯/还原来解毒。随后，通过用零价镁（Mg 0 4）沉淀以形成不溶性羟基氧化物来回收重金属部分，所述不溶性羟基氧化物通过过滤回收。将纯化的ASS级分（现在不含HOC和TM）返回以清洁更多的污垢。通过这个过程，这两类有毒物质都转化为无毒的产品。