Pretreatment-Catalyst effects and the combined severity parameter

Abstract

Fractionation of lignocellulosic materials into high-yield cellulosic solid components can be accomplished with acid-catalyzed aqueous and mixed aqueous and nonaqueous media, with the latter leading to high lignin and xyland removal. Concepts combining only time and temperature pulping profile with catalyst concentration are presented to correlate these two types of fractionation methods with pulping variables. Severity concepts combining time and temperature only are often used in the pulp and paper industry. The present extension of this concept produces phenomenological descriptions that permit comparisons of different proceses and yield some pseudokinetic parameters for aspen (Populus tremuloides) acid-catalyzed fractionation. © 1990 Humana Press Inc.