| abstract |
An acidic water-based process was developed for the synthesis of anionic lignin copolymers with adjustable MW, thermal stability and solubility in water. The anionic lignin copolymer described herein comprises: a molecular weight of 5,000 to 7.4×10 5 g/mol; and a charge density of −1 to −7.2 meq/g. The anionic lignin copolymers described herein which have a molecular weight range of 000-50,000 g/mol can be used as dispersants of negatively charged molecules or particles in numerous process or wastewater streams (e.g. concrete admixtures, gypsum slurries, textile dye) while such copolymers in a molecular weight range of 90,000-740,000 g/mole can be used as flocculants of positively charged molecules or particles in numerous process and wastewater streams including industrial and municipal systems and sludge dewatering in the textile dye, pulp & paper, mining and oil industries. |