Multi-objectives optimization on microwave-assisted-biological-based biogas upgrading and bio-succinic acid production.

ABSTRACT

This study represents the first investigation of bio-succinic acid (bio-SA) production with methane enrichment using carbon-dioxide-fixating bacteria in the co-culture of ragi tapai and macroalgae, Chaetomorpha. Microwave irradiation has also been introduced to enhance the biochemical processes as it could provide rapid and selective heating of substrates. In this research, microwave irradiation was applied on ragi tapai as a pre-treatment process. Factors such as microwave irradiation dose on ragi tapai, Chaetomorpha ratio in the co-culture, and pH value were studied. Optimal conditions were identified using Design-Expert software, resulting in optimal experimental biomethane and bio-SA production of 85.7 % and 0.65 g/L, respectively, at a microwave dose of 1.45 W/g, Chaetomorpha ratio of 0.9 and pH value of 7.8. The study provides valuable insights into microwave control for promoting simultaneous methane enrichment and bio-SA production, potentially reducing costs associated with CO2 capture and storage and biogas upgrading.