Chain elongation with reactor microbiomes: upgrading dilute ethanol to medium-chain carboxylates

• DOI: 10.1039/c2ee22101b
• Publication Date: 2012-06-13T11:30:30Z
• Authors: Matthew T. Agler; Catherine M. Spirito; Joseph G. Usack; Jeffrey J. Werner; Largus T. Angenent
• Keywords: Caproic Acid; Hydrodeoxygenation

Ethanol distillation in the biofuel industry is energetically expensive because ethanol completely miscible water. Upgrading into a hydrophobic chemical that easier to separate would circumvent current fossil-fuel consumption for distillation. Here, we shaped reactor microbiome sequentially elongate carboxylic acids with 2-carbon units from dilute yeast-fermentation beer. Our continuous bioprocess produced n-caproic acid, 6-carbon-chain acid more valuable than ethanol. No antimicrobials inhibit methanogens were necessary. In-line product extraction achieved an production rate exceeding 2 grams per liter of volume day, which comparable established bioenergy systems microbiomes. Incorporation other organics found beer increased mass carbon by 10% compared