Prehydrolysis of Bamboo-effect of pH

Abstract

Studies in this Paper have been carried out with a view to understand Ihe effect of pH on prehydrolysis of bamboo (Dendrocalamus strictus). The bamboo chips have been cooked with 1% H₂SO₄ H₂O and 10% NaOH for 90 minutes and 150 minutes The acidic, aqueous and soda Lignins have been analysed These results show that pulp yield decreases at higher pH and at more cooking time, and is also effected by the final pH of the prehydrolysates. The lignin yield from prebydrolysate decreases as the pH goes towards acidic side. The methoxyl content in isolated lignins decrease with the increase of lignin yield, while total-OH increases with the increase in lignin yield. The ratio of syringaldehyde to vanillin is less in lignins Obtained at higher prehydrolysis time. The acidic and aqueous lignins are less condensed than soda lignin.