Abstract
Cost-efficient production of renewable chemicals depends not only on cheap feedstocks and efficient reactor technology, but also on efficient downstream processing technologies. Levulinic acid, a product of hydrolysis of biomass, is a renewable chemical with various potential applications in several industries, such as chemical, pharmaceutical and food. However, its production in large scale is hampered because of deficient reactor and recovery technologies. Recovery of levulinic acid is a cumbersome task since degradation of biomass in high temperatures also leads to production of humins. In this work, the recovery of levulinic acid from biomass hydrolysate was evaluated using the UNIFAC group contribution method. As consequence of the dilute nature of the process and the presence of water, two scenarios with two different organic, aprotic solvents were tested to perform liquid-liquid extraction of levulinic acid: 2-methyltetrahydrofuran (MTHF) and hexane. Both scenarios were optimized considering the all process requirements for solvent recovery and recycling, and the overall process was evaluated in terms of capital and operational expenditures. Although hexane is a traditional extraction solvent option in industry, results demonstrated that the use of MTHF leads to a recovery cost 26% lower than using hexane. Therefore, this investigation using a group contribution method demonstrated the potential of using MTHF in the recovery of levulinic acid. The potential of this process needs to be validated experimentally in the future, and such approach contributes to the development of separation processes for production of renewable chemicals in biorefineries.
