Isolation and characterization of wood components with aqueous acetic acid

Abstract

A study was conducted on the isolation of poplar (Populus × euramaricana (Dode) Guineir cv. l-72/58) wood components with aqueous acetic acid (AcOH) containing small amounts of sulfuric acid. The reaction time, concentration of acetic acid, ratio of liquor to wood, and concentration of acid catalyst were investigated to examine their effects on the fractionation of wood components. The three main separated components were characterized. The results showed that the optimum conditions for fractionation of poplar wood components were: 0.3% H₂SO₄ in reaction solution, ratio of liquor to wood 6, reflux time 3 h, and 90% AcOH. The residues were mainly composed of α-Cellulose and hemicellulose. The water insoluble precipitate (acetic acid lignin, AcL) had a low weight-average molecular weight range from 341 to 253 (Mw) and a narrow molecular weight distribution from 1.1 to 1.2. The sugar analysis revealed the solubilized products resulted mainly from hemicellulose and exited as monosaccharides.

Keywords

Aqueous acetic acid / Sulfuric acid / Component separation / Poplar wood

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