pH-Uncontrolled lactic acid fermentation with activated carbon as an adsorbent

Area of Science:

• Biotechnology
• Chemical Engineering
• Materials Science

Background:

• Lactic acid fermentation is crucial for producing various chemicals and materials.
• High concentrations of lactic acid can inhibit microbial fermentation processes.
• Efficient separation and purification of lactic acid are vital for downstream applications.

Purpose of the Study:

• To develop a novel process using activated carbon (AC) for in situ lactic acid removal during fermentation.
• To investigate the adsorption and desorption characteristics of lactic acid on AC.
• To evaluate the feasibility of using AC-treated lactic acid for oligomerization.

Main Methods:

• Utilized activated carbon as an adsorbent for in situ lactic acid removal.
• Optimized adsorption conditions, considering the effect of pH.
• Employed acetone for lactic acid desorption from AC.
• Performed lactic acid oligomerization using the desorbed lactic acid.

Main Results:

• Activated carbon effectively adsorbed lactic acid, mitigating fermentation inhibition.
• In situ AC removal significantly increased lactic acid fermentation productivity and yield.
• Acetone desorption yielded lactic acid with high optical purity (99.5%).
• Obtained lactic acid oligomers with >96% optical purity and M(w) of 2400.

Conclusions:

• Activated carbon is a promising adsorbent for enhancing lactic acid fermentation.
• The AC-based process allows for efficient separation and recovery of high-purity lactic acid.
• The recovered lactic acid is suitable for producing high-quality oligomers.