Pre-Extraction and Its Impact on the Alkaline Pulping of Bagasse

A water hydrolysis was applied to bagasse prior to soda-AQ pulping in order to remove pith from bagasse and to extract hemi-celluloses for use as biomaterials. The extraction was performed at 150 degrees C for 1 h. It resulted in a recovery of about 160 kg of hemicellulose per ton of whole bagasse, while the pulp yield from the soda-AQ process was 4.3% lower than the non-extracted bagasse pulp. The pre-extracted bagasse pulp had less fines, resulting in an improvement in the pulp drainage in comparison with the non-extracted bagasse pulp. The Soda-AQ pulp from the pre-extracted bagasse had higher tear index but lower tensile index than the non-extracted bagasse pulp. The pre-extraction process allowed a lower alkali charge to reach to the same degree of delignification.