Ethanol-water pulping of oil palm fibers using hydrochloric acid as a catalyst and test paper characterization

Oil palm (Elaeis guineensis Jacq.) fibers of trunks, empty fruit bunches, and fronds, were pulped in an ethanol/water system with a catalyst, using a laboratory-scale digester. The project was designed to investigate catalyzed organosolv pulping and to optimize the effects of process variables on pulp quality and yield. HCl was found to be an effective catalyst for pulping oil palm fibers in ethanol/water. The screened pulp yield, amount of shives, kappa number, and paper strength properties were affected markedly by the addition of HCl in various amounts. Oil palm fibers produced pulps with satisfactory yields and quality when cooked for 120 minutes at a liquor/fiber ratio of 12/1 and 180 degrees C in a 60% aqueous ethanol solution both with and without HCl as a catalyst. When 20% HCl was added to the aqueous ethanol, the fronds produced a pulp with a small kappa number (22.0) at a yield of 39.8%. The amount of shives was 3.2% of the feedstock. The empty fruit bunches afforded a pulp with a kappa number of 27 at the maximum yield of 40.3% using 55% HCl as a catalyst. The amount of shives produced under these conditions was 6.2%. When the trunks were cooked under the same conditions with 30% HCl, a 39.4% yield of pulp with a kappa number of 22 and a shives content of 3.2% was obtained.