Decomposition of Cellulose by Continuous Near-Critical Water Reactions

Abstract

Abstract: A pilot-scale apparatus for continuous supercritical and near-critical water reaction was
set up. A high- pressure slurry supplying system was developed to feed the solid material-
water slurries. The apparatus features temperature up to 600℃, pressure up to 40MPa,
residence time from 24s to 15min, maximum amount of slurry supply of 2.4 L.h-1, maximum
solid content of slurry up to 10%(by mass) for cellulose from Merck, and resistance to
corrosion. Long-time runs of decomposition of cellulose were carried out and steady runs
were confirmed. Kinetics of cellulose decomposition was studied. The apparent activation
energy evaluated was 147kJ·mol-1. In addition, a new three-step pathway for cellulose
hydrolysis was proposed. The derived kinetic equation is in good agreement with the
experimental data.

Key words: cellulose, near-critical water, decomposition kinetics, continuous process

摘要： A pilot-scale apparatus for continuous supercritical and near-critical water reaction was
set up. A high- pressure slurry supplying system was developed to feed the solid material-
water slurries. The apparatus features temperature up to 600℃, pressure up to 40MPa,
residence time from 24s to 15min, maximum amount of slurry supply of 2.4 L.h-1, maximum
solid content of slurry up to 10%(by mass) for cellulose from Merck, and resistance to
corrosion. Long-time runs of decomposition of cellulose were carried out and steady runs
were confirmed. Kinetics of cellulose decomposition was studied. The apparent activation
energy evaluated was 147kJ·mol-1. In addition, a new three-step pathway for cellulose
hydrolysis was proposed. The derived kinetic equation is in good agreement with the
experimental data.

关键词: cellulose;near-critical water;decomposition kinetics;continuous process

LU Xiuyang, SAKODA Akiyoshi, SUZUKI Motoyuki. Decomposition of Cellulose by Continuous Near-Critical Water Reactions[J]. .

吕秀阳, 迫田章义, 铃木基之. 纤维素在近临界水中连续分解的研究[J]. CIESC Journal.

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