Use of Lignochemicals and Humic Acids to Remove Heavy Metals from Process Waste Streams

摘要

The Bureau of Mines investigated the feasibility of removing heavy metals from mineral-process waste streams by precipitation with lignochemicals and humic acids. Lignochemicals are byproducts from the paper industry, while humic acids are obtained by caustic treatment of peat, subbituminous coal, and lignite. These high-molecular-weight organic materials have many functional groups, which can coordinate and form innercomplex salts with heavy metals that are crystalline precipitates. Filtering of a humic-acid- or lignochemical-treated solution or waste stream containing these precipitates removes the heavy metal sequestrates.