Kinetic modeling for enzymatic hydrolysis of pretreated sugarcane straw

• Enzymatic hydrolysis of sugarcane straw at high solids concentration was modeled.
• Parameter correlation was reduced simplifying the model without affecting fidelity.
• Model includes enzyme adsorption, xylose formation, end-product inhibition and substrate reactivity.
• High-solids saccharification over a broad range of loading conditions was described with accuracy.

A semimechanistic multi-reaction kinetic model was developed for modeling enzymatic hydrolysis of pretreated sugarcane straw (SCS) at high-solids concentration. The model, including: enzyme adsorption, xylose formation, end-product inhibition and substrate reactivity, was adjusted from a reference condition (enzyme concentration of 10 FPU/g-cellulose and solid loading of 15% w/v, dry basis). A simplified model was also proposed to overcome high parameter correlation and improve model fidelity. Predictive capacity of both simplified and original model was verified for different enzyme concentration (5–60 FPU/g-cellulose), solids loading (10 and 20 %) and end-product sugar inhibition (30 and 60 g/L glucose, 10 g/L cellobiose and 10 g/L xylose). The glucose concentration was predicted with reasonable accuracy by the simplified model, even under critical conditions of sugar-inhibition. The model is able to describe batch saccharification of pretreated SCS at high-solids concentrations.