The broader impact of this Small Business Innovation Research Phase I project is reduced costs of road and highway infrastructure repairs and environmental benefits from the use of a low-cost biodegradable and non-corrosive deicer substitute for salts. Deicing chemicals are applied to roads in winter for safety. Typical salts are highly corrosive to concrete, reinforcing steel, and bridge decks, and hence cause billions of dollars in road repair and infrastructure rehabilitation costs. Because these salts do not biodegrade, they accumulate in the environment and increase salinity in lakes and ground waters, as well as in water supplies. Acetate-based chemicals are effective deicers with minimal corrosion and environmental effects, but they can be expensive to produce. This project will repurpose wastes to produce a low-cost deicer for reduced infrastructure costs and enhanced environmental quality.The proposed project will provide a new cost-effective low pH bioconversion process for the production of acetic and lactic acids from carbohydrate wastes. There are currently no industrial bioconversion facilities for the production of acetic acid due to the high recovery costs for the sorption or extraction of the acid from the broth at neutral pH. This project will advance bioconversion of sugars at sufficiently low pH values where the product recovery efficiency is high. Acid recovery by adsorption on resins or liquid-liquid extraction is about twelve times more efficient with the proposed process than with anaerobic fermentations that operate at neutral pH. This project will develop a process to utilize abundantly available organic and inorganic wastes in the production of the acetate deicer. Hemicellulose, the second most abundant carbohydrate in nature, is not utilized in ethanol fermentations due to the low efficiency of bioconversion. Hemicellulose hydrolysate will be used as substrate in the proposed process. Continuous fermentations at low pH values will be optimized for high organic acids productivities. Multicomponent adsorption studies will be conducted to optimize the schemes for the recovery of the organic acids from the fermentation broth.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
