Improving saccharification efficiency of corn stover through ferric chloride-deep eutectic solvent pretreatment

Area of Science:

• Biomass Pretreatment
• Green Chemistry
• Biorefining

Background:

• Lignocellulosic biomass, such as corn stover, is a sustainable resource for biofuels.
• Efficient pretreatment is crucial for breaking down biomass structure and improving downstream processing.
• Current methods often face challenges with efficiency and environmental impact.

Purpose of the Study:

• To develop an effective deep eutectic solvent (DES) and Iron(III) chloride (FeCl3) combination pretreatment system.
• To enhance the removal of lignin and hemicellulose from corn stover (CS).
• To improve the saccharification efficiency of CS for biofuel production.

Main Methods:

• Preparation of a ChCl-based DES using N-(2-hydroxyethyl)ethylenediamine (NE) as the hydrogen-bond donor (ChCl:NE).
• Combination pretreatment of CS using a mixture of ChCl:NE (60 wt%) and FeCl3 (0.5 wt%) at 110 °C for 50 min.
• Analysis of lignin and xylan removal, enzymatic hydrolysis activity, and reducing sugar yield.

Main Results:

• The FeCl3/ChCl:NE system effectively removed 87.0% of lignin and 55.9% of xylan from CS.
• Enzymatic hydrolysis activity of the pretreated CS was 5.5 times higher than that of untreated CS.
• A high reducing sugar yield of 98.6% was achieved from the pretreated CS.

Conclusions:

• The FeCl3/ChCl:NE pretreatment significantly disrupted the cellulose crystal structure of CS.
• This method enhances the removal of lignin and hemicellulose, leading to improved cellulose and hemicellulose conversion into sugars.
• The combined FeCl3 and DES pretreatment shows high potential for the biological refining of lignocellulose.