High yields of sugars via the non-enzymatic hydrolysis of cellulose

摘要

Given the cost of cellulosics (quasi-homogeneous residual feeds range in North America, between $US 60-80/tonne, dry basis, FOB conversion plant) their fractionation and subsequent use of the intermediate fractions is a strategy that makes economic sense. Furthermore, it permits the isolation of cellulose with low contents of lignin and hemicellulose. Once the cellulose is isolated, its use as a chemically pulped fibre and the conversion of the fines into glucose becomes possible. Our group has been working on the chemical depolymerisation of the cellulose (both the fines and the fibres as well) using highly ionic solutions. The method implies recovery of both anions and cations by state of the art technologies. This paper presents the fractionation + ionic decrystallization and depolymerisation approach, provides and discusses its energy balance and compares it with the enzymatic route for hydrolysis in applications to < 40 MML Biofuels/y plants which correspond to < 100 000 t/y of input lignocellulosics, dry basis.