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Updated: May 3, 2026
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Experimental Protocol for Biodiesel Production with Isolation of Alkenones as Coproducts from Commercial Isochrysis Algal Biomass
Published on: June 24, 2016
23.8K
Methane production from marine microalgae Isochrysis galbana
Nathalia O Santos1, Suzana M Oliveira1, Larissa C Alves2
1Department of Biochemical Engineering, School of Chemistry, Federal University of Rio de Janeiro, Cidade Universitária, Centro de Tecnologia, Bl. E, Sl. 203, Ilha do Fundão, 21941-909 Rio de Janeiro, Brazil.
Bioresource Technology
|February 18, 2014
Summary
Marine microalgae pretreatment enhances methane production. Optimizing acid hydrolysis and reducing sodium improved biogas yields, demonstrating effective biomass energy conversion.
Area of Science:
- Biotechnology and Bioengineering
- Renewable Energy Sources
- Environmental Science
Background:
- Marine microalgae, such as Isochrysis galbana, are a potential feedstock for biofuel production.
- Pretreatment is crucial for improving the efficiency of microalgal biomass conversion into methane.
- Previous studies highlight challenges in anaerobic digestion due to inhibitory substances.
Purpose of the Study:
- To assess methane production from Isochrysis galbana before and after mechanical and chemical pretreatments.
- To optimize hydrolysis conditions (temperature, acid concentration, biomass concentration) for enhanced methane yield.
- To investigate the impact of sodium inhibition on anaerobic digestion and evaluate prewashing strategies.
Main Methods:
- Mechanical pretreatment to increase soluble Chemical Oxygen Demand (COD).
- Experimental design to evaluate hydrolysis conditions: temperature (T), sulfuric acid concentration (AC), and particulate COD (CODp).
- Anaerobic digestion of pretreated biomass, followed by prewashing to remove inhibitory sodium.
Main Results:
- Mechanical pretreatment increased soluble COD by 61.7%.
- Optimal hydrolysis at 40°C with 0.2% (v/v) acid for 16h yielded 9.27 L CH4/kg VS.
- Biomass prewashing to remove sodium increased methane yield by 71.5% after acid hydrolysis.
Conclusions:
- Mechanical and acid pretreatments significantly enhance methane production from marine microalgae.
- Hydrolysis conditions, particularly temperature and acid concentration, are critical for optimizing biogas yield.
- Sodium inhibition is a major limiting factor in microalgal anaerobic digestion, necessitating prewashing.
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