KINETIC MODELLING OF CHEMICAL AND ENZYMATIC PROCESSES WITH LIGNOCELLULOSIC FIBER MATERIALS

Optimization of pulping, bleaching and biorefining processes requires a good understanding of reaction kinetics.The kinetics of the processes are described by kinetic equations valid for processes taking place at heterogeneous surfaces. The investigation clarifies the influence of operating parameters on the effectiveness of various processes with lignocellulosic fibre materials. The kinetics of oxygen delignification are described by a modified form of the topochemical kinetic equation, while the same kinetic mechanism was found to govern both chlorine dioxide bleaching and xylanase-assisted bleaching. The kinetics of hydrolysis with cellulase complexes is described by an exponential kinetic equation.Common kinetic expressions were developed to describe the combined effects of reaction time, enzyme concentration, temperature, and other relevant operating parameters on process efficiency.