STUDIES OF BAGASSE NEUTRAL SODIUM-SULFITE PULPING WITH LOWER PERMANGANATE NUMBER AND HIGHER YIELD

Bagasse neutral sodium sulfite pulping has been studied. The results o btained during pulping are showed in tile following: In conditions of 18%Na2SO3 charge, 3%+Na2CO3 charge and cooking at 165 degrees for 60 m in; bagasse pulp could be obtained with a yield of 65.82%, permanganat e number 9.14, brightness 50% and opacity 92.65%. Before raising tempe rature to 140 degrees, the li,gnin sulfonation rate was greater than t he delignification rate. As the temperature was raised to 165 degrees, a value maintained for 60 min, the sulfonated lignin was dissolved ra pidly, and bagasse was defiberized. The strengths and opacity of tile pulp sheet satisfied the demands for newsprint. The results of the SEM -EDXA and IR spectral analysis and the data of the dissolved carbohydr ate have revealed tile reasons for higher yield and brightness and low er permanganate number.