Bio based phenolic resins and adhesives derived from forestry residues wastes and lignin

Abstract

The work presented here aims to produce bio-phenolic compounds from forestry biomass (residues, wastes and lignin), and substitute petroleum-based phenol with the bio-phenolic compounds to produce high quality bio-based phenol formaldehyde (PF) resins. For the production of bio-phenolic compounds from biomass, alcohol (methanol or ethanol) and water showed synergistic effects on biomass direct liquefaction. 65 wt% of bio-oil and a biomass conversion at > 95% were obtained at 300 C for 15 min in the 50%/50% (w/w) co-solvent of either methanol-water or ethanol-water. At a temperature higher than 300 C, conversion of bio-oil to char was significant via re-polymerization reactions. The Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography-Mass Spectroscopy (GC-MS) analyses of the obtained bio-oils confirmed the presence of primarily phenolic compounds and their derivatives (such as benzenes), followed by aldehyde, long-chain (and cyclic) ketones and alcohols, ester, organic acid, and ether compounds. The Gel Permeation Chromatography (GPC) results suggested that hot-compressed ethanol as the liquefaction solvent favored lignin degradation into monomeric phenols. The X-ray Diffraction (XRD) patterns of Eastern White Pine (Pinus strobus L.) wood before and after the liquefaction displayed that the cellulosic structure of the feedstock was completely converted into amorphous carbon at around 300 C, and into crystalline carbon at about 350 C.