By Pradeep Divvela, Project Chemist, Kelso, WA
Sequential extraction is an analytical process that chemically leaches metals out of soil, sediment and sludge samples. The purpose of sequential “selective” extraction is to mimic the release of the selective metals into solution under various environmental conditions.
One commonly used sequential extraction procedure is designed to partition different trace metals based on their chemical nature.
The sequential extraction process is typically accomplished in four (4) steps using: