SEDL / STP / STP1442-EB / STP11564S

Use of Selective Sequential Extraction for the Remediation of Contaminated Sediments

Mulligan, CN
Associate Professor and Ph.D. student, Civil and Environmental Engineering, Concordia University, Montreal, Quebec

Azma, BD
Associate Professor and Ph.D. student, Civil and Environmental Engineering, Concordia University, Montreal, Quebec

Pages: 16    Published: Jan 2003

Download this paper for $25 PDF (352K)          View License Agreement
Abstract

The interaction of contaminants with sediments is a very complex phenomenon and means are required to understand this matter more fully. To determine the speciation of metals in sediments (the distribution of elements among chemical forms or species), specific extracts are used in a process called sequential selective extraction. This method can be used to determine if heavy metals are removable by remediation techniques or to predict removal efficiencies. Sequential extraction can be employed for the evaluation of the most appropriate sediment remediation technology and for monitoring remediation procedures. A biosurfactant, rhamnolipid, was used to remove organic-bound copper and carbonate-bound zinc. Exchangeable, carbonate, reducible oxide and organic fractions are amenable to washing techniques, and residually bound contaminants are not economical or feasible to remove. This information is important in designing the most appropriate conditions for sediment washing.