A Novel Method for Enhanced Recovery of Lignin from Aqueous Process Streams

Abstract

This study demonstrates that acid precipitation of lignin in the presence of magnetite followed by an applied magnetic field provides a simple method for enhanced lignin recovery from an aqueous stream. The extraction procedure was shown to be sensitive to the relative charge of magnetite and solution pH. Under optimized conditions, 93 wt.% of the softwood lignin from a kraft cooking liquor could be recovered employing this novel separation approach.

Keywords:

• Lignin
• isolation
• agglomeration
• magnetic separation
• magnetite

The authors thank the IPST@GT endowment and the National Research Initiative of the USDA Cooperative State Research, Education and Extension Service, grant number 2003‐35504‐13620, for the support of these studies.