Biodiesel production from rice bran by a two-step in-situ process

Area of Science:

• Biomass Conversion
• Green Chemistry
• Chemical Engineering

Background:

• Rice bran is a rich source of lipids suitable for biofuel production.
• High free fatty acid (FFA) content in rice bran can hinder efficient transesterification.
• A two-step in-situ approach offers a potential solution for processing high-FFA feedstocks.

Purpose of the Study:

• To investigate a two-step in-situ transesterification process for fatty acid methyl ester (FAME) production from rice bran.
• To optimize conditions for reducing high free fatty acid (FFA) levels in rice bran.
• To achieve high yields of FAMEs from different rice bran sources.

Main Methods:

• Employed a two-step in-situ method: acid-catalyzed esterification followed by base-catalyzed transesterification.
• Optimized reaction parameters including methanol ratio, catalyst concentration, temperature, stirring rate, and time.
• Processed two types of rice bran with initial FFA content of 3% and 30%.

Main Results:

• Reduced FFA content to below 1% in the first esterification step for both rice bran types.
• Achieved high FAMEs yields of 96.8% for rice bran A and 97.4% for rice bran B in the second transesterification step.
• Demonstrated the effectiveness of the two-step in-situ process for high-FFA rice bran.

Conclusions:

• The developed two-step in-situ transesterification is highly effective for producing FAMEs from rice bran, even with high initial FFA content.
• This method offers a viable pathway for converting rice bran into valuable biofuels.
• Optimized conditions ensure efficient conversion and high yields, making rice bran a promising feedstock for biodiesel production.