Deep eutectic solvent pretreatment and subsequent saccharification of corncob.

Area of Science:

• Biomass Pretreatment
• Green Chemistry
• Renewable Energy

Background:

• Ionic liquids (ILs) are effective for lignocellulosic biomass pretreatment but are costly and energy-intensive.
• Deep eutectic solvents (DESs) present a promising, cost-effective alternative with similar properties to ILs.
• Corncob residues are an abundant lignocellulosic material suitable for biofuel production.

Purpose of the Study:

• To evaluate the efficacy of three DES systems in pretreating corncob residues.
• To assess the impact of DES pretreatment on biomass composition and enzymatic digestibility.
• To determine the yield of fermentable sugars after DES pretreatment and enzymatic saccharification.

Main Methods:

• Pretreatment of corncob residues using choline chloride with glycerol, imidazole, or urea.
• Characterization of pretreated biomass: lignin content, sugar concentration, crystallinity index.
• Enzymatic saccharification of pretreated biomass to determine fermentable sugar yield.

Main Results:

• DES pretreatment reduced lignin and hemicellulose content, increasing overall biomass crystallinity.
• Cellulose crystallinity could be reduced depending on the DES system and conditions.
• Enzymatic saccharification rates and extents were significantly enhanced.
• Recovered 41 g of fermentable sugars (27 g glucose, 14 g xylose) per 100 g of corncob (76% overall carbohydrate conversion).

Conclusions:

• DESs are effective for lignocellulosic biomass pretreatment, improving enzymatic digestibility.
• DES pretreatment offers a viable and efficient method for enhancing fermentable sugar production from corncob residues.
• This approach supports the sustainable production of biofuels and biochemicals from agricultural waste.