Experimental studies for levulinic acid production from whole kernel grain sorghum

Area of Science:

• Biomass Conversion
• Green Chemistry
• Chemical Engineering

Background:

• Levulinic acid is a valuable platform chemical with diverse industrial applications.
• Developing sustainable and economical production methods is crucial for its widespread adoption.
• Sorghum grain offers an abundant and low-cost renewable feedstock.

Purpose of the Study:

• To establish an efficient method for synthesizing levulinic acid from whole kernel sorghum grain.
• To investigate the impact of key reaction parameters on levulinic acid yield.
• To develop a predictive model for optimizing levulinic acid production.

Main Methods:

• Grinding whole kernel sorghum grain into flour.
• Reacting sorghum flour with varying concentrations of sulfuric acid (2-8%) at different temperatures (160-200°C) in a pressurized reactor.
• Employing a stepwise heating scheme to enhance levulinic acid yield.
• Utilizing linear regression to model the relationship between reaction parameters and yield.

Main Results:

• Levulinic acid yield increased with higher reaction temperatures and sulfuric acid concentrations.
• Flour loading exhibited an inverse relationship with levulinic acid yield.
• A maximum levulinic acid yield of 32.6% was achieved under optimal conditions (200°C, 8% H2SO4, 10% flour loading).
• The developed linear regression model accurately predicted yield (R² = 0.88).

Conclusions:

• Whole kernel sorghum grain is a viable and economical feedstock for levulinic acid production.
• Optimizing reaction temperature, sulfuric acid concentration, and flour loading is key to maximizing yield.
• The established method and predictive model offer a promising route for industrial-scale levulinic acid synthesis.