Journal of Korea Technical Association of The Pulp and Paper Industry (펄프종이기술)

Korea Technical Association of the Pulp and Paper Industry (한국펄프종이공학회)
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Delignification Kinetics of Trema orientalis (Nalita) in Kraft Pulping

  • Jahan, M. Sarwar (Pulp and Paper Research Division, BCSIR Laborities) ;
  • Rubaiyat, A. (Department of Applied Chemistry and Chemcial Technology, Dhaka University) ;
  • Sabina, R. (Department of Applied Chemistry and Chemcial Technology, Dhaka University)
  • Published : 2007.12.31
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Abstract

Kraft pulping of Trema orientalis (Nalita) was studied in order to find kinetic data for delignification. Pulping runs were carried out in the temperature range of $160-180\;^{\circ}C$ under constant and well-defined conditions. The delignification was found to be first order with respect to residual lignin and was chemically controlled. The rate of delignification reaction was increased 1.11-1.23 for $10\;^{\circ}C$ temperature increase in the range of $160-180\;^{\circ}C$ range. A mean value of 93% of lignin was removed at the transition between bulk and residual delignification. The influence of cooking temperature on the rate constant was expressed by an Arrhenius-type equation. The obtained activation energy of the delignification reaction was 6,164 cal/mol. The transition point between bulk and residual phase was shifted to lower lignin and carbohydrate yield with the increase of temperature.

Keywords

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