In situ transesterification of highly wet microalgae using hydrochloric acid

Area of Science:

• Biotechnology
• Chemical Engineering
• Renewable Energy

Background:

• Microalgae are a promising feedstock for biodiesel production.
• Processing highly wet microalgae presents significant challenges due to water content.
• Efficient and cost-effective methods for microalgal lipid conversion are needed.

Purpose of the Study:

• To investigate the in situ transesterification of wet microalgae using hydrochloric acid (HCl) as a catalyst.
• To optimize reaction conditions for maximizing fatty acid methyl ester (FAME) yield.
• To compare the efficacy of HCl with sulfuric acid (H2SO4) for this process.

Main Methods:

• In situ transesterification of wet microalgae in a one-pot reaction.
• Utilizing hydrochloric acid (HCl) as the catalyst.
• Investigating the effects of temperature, catalyst amount, reactant concentration, and solvent type on FAME yield.

Main Results:

• Achieved over 90% FAME yield at 95°C.
• HCl catalyst demonstrated high tolerance to moisture levels above 80%.
• HCl required less catalyst and solvent compared to H2SO4, yielding 15wt.% higher FAME for equimolar catalyst amounts.

Conclusions:

• In situ transesterification using HCl is a feasible and efficient method for biodiesel production from wet microalgae.
• HCl offers advantages over H2SO4 in terms of moisture tolerance and reduced catalyst/solvent requirements.
• This approach provides a practical pathway for sustainable biofuel generation from algal biomass.