2000 Volume 54 Issue 10 Pages 1394-1402,031
In order to establish a new pulping process of hardwood and annual plants, a HBS pulping process with aqueous solvent of high boiling point was investigated using birch, beech and eucalyptus wood chips for hardwood and oil-palm wastes (empty fruit bunch and frond), agricultural wastes (baggase, rice straw and wheat straw) and kenaf stalk as annual plants. All of the materials were pulped with 80% aqueous HBS containing 0-10% AcOH at 190-200°C for 2-3h. The strength properties of HBS pulp were inferior to those of corresponding kraft pulp, but comparable to those of organosolv pulps. Waste liquor and washings were divided into water insoluble HBS lignin and water solubles. RHBS, which was obtained by evaporating of the water fraction from the latter, consisted of HBS, sugars, and low-molecular lignin and sugar-modified products. A 80% Aqueous RHBS was able to use at least 5 times as a pulping solvent indicating that the HBS method is the pulping process of wood and annual plants with saving-energy, saving-resources and non-polution.