BLEACHING OF WHEAT STRAW, AN ALTERNATIVE CELLULOSIC (HARD) FIBER FOR POTENTIAL INDUSTRIAL APPLICATIONS

摘要

Since the lignin in straw serves as cement that keeps the cellulose together, it is impossible to achieve high whiteness without removing it from the matrix structure and disintegrate the straw. The high content of lignin in the straw made it very difficult to bleach it to a complete white just with hydrogen peroxide. For the straw stalks given a dilute acetic acid treatment after bleaching, creamy white colors can be achieved with hydrogen peroxide concentrations higher than 1.0%, pH 10.5, and bleaching temperature of 80℃ for 30 to 45 minutes. These conditions also preserve the structure of the ground straw.