In-situ polymerization of lignocelluloses of autohydrolysis process with acrylamide

Abstract

In the present study, the hydrolysates generated via autohydrolysis of spruce wood chips were directly used as feedstock for producing coagulants. The in-situ polymerization of acrylamide (AM) and lignocellulose (LC) of hydrolysates was successfully conducted. The reaction was optimized to generate lignocellulose-acrylamide (LC-AM) with the highest molecular weight (41,060 g/mol) and charge density (–0.25 meq/g) under the optimum conditions, which were 3 h, 60 ℃, 4% (w) initiator based on the dried mass of hydrolysate, and an AM/LC molar ratio of 5.63. A nuclear magnetic resonance (NMR) spectroscopy confirmed the grafting of acrylamide on LC. Other properties of LC-AM were characterized by the elemental analyzer, zeta potential analyzer, gel permeation chromatography (GPC), and particle charge detector (PCD). The LC-AM was applied as a coagulant for removing ethyl violet dye from a simulated dye solution. The results indicated that 47.2% dye was removed from the solution at a low dosage of 0.2 g/g. The dual flocculation of LC-AM with other polymers for dye removal is suggested to further improve its effectiveness.

Keywords

• Polymerization
• Hydrolysate
• Lignocellulose
• Acrylamide
• Biorefining