Enzymatic hydrolysis of cellulose was extremely complex because of the unclear enzymatic hydrolysis

deactivation mechanisms and many factors that affect the heterogeneous system. Therefore

it is difficult to build a mechanistic model to study cellulose hydrolysis by cellulase. Under some assumed conditions such as the secondorder cellulase deactivation and quasi-steady state theory

a semi mechanistic and empirical model describing the relationship between product concentration and time

the initial enzyme concentration was deduced. The mathematic model was a simple mathematic function that contained only two parameters. The experimental result was in accordance with the deduced mathematic model

where the correlation coefficients (

R

2) were above 0.98. The relationship between initial enzyme concentration and initial hydrolysis rate calculated from the mathematic model showed good agreement with another type of Henri-Michaelis-Menten equation proposed by Bailey

where the

R

2 was 0.977 3. The maximum hydrolysis rate and half saturation constant was 2.742 4 g/(L·h) and 3.013 0 g/L

respectively. It was shown from the model that the rate constant of cellulase deactivation decreased when initial enzyme concentration increased under the certain substrate concentration

and the relationship between them was linear. The cellulase deactivation speed increased with the increase of enzyme concentration.