In the 2004 DoE report, on renewable chemicals from biomass, C4, 1,4 dicarboxylic acids was selected as the most promising category. MBI has developed processes for the production of two such acids (fumaric acid and succinic acid). Both processes share the potential to use both currently available corn-based and (when they become commercially available) cellulosic sugars.
Both of these processes have been scaled up to 3000 l scale, including downstream product separation and purification to generate > 100 kg of finished product for application testing. Economic models have been developed and the cost of manufacturing estimated to be favorable in comparison to petrochemical based alternatives.
Whilst one of the processes is an anaerobic bacterial CO2-fixing fermentation the other is an aerobic fungal process. The differences, challenges and advantages of these two approaches will be discussed, together with the importance of product separation and purification steps in the development of a commercially viable and scalable bio-based technology.