Multiscale Conceptual Design of a Scalable and Sustainable Process to Dissolve and Regenerate Keratin from Chicken Feathers

A multiscale strategy was used to conceptually designand economicallyanalyze a scalable and sustainable process for dissolving and regeneratingkeratin from chicken feathers by using a sodium acetate-ureadeep eutectic solvent as the reacting media. In this study, the recoveryand recycling of the solvent were also considered. Moreover, molecularmodeling of the solvent, keratin and its derivatives, property estimationof the corresponding mixtures, and simulation of the different processalternatives proposed, including the equipment sizing, estimationof energy needs, and economic analysis were presented. A quasi-planarcluster governed by H-bond interactions resulted in the most stableconfiguration of the deep eutectic solvent. Molecular models havingmolecular weights higher than 1.400 g/mol were created to representthe keratin species, where the most abundant amino acids in the featherswere included and conveniently ordered in the chain. Property estimationsperformed with the conductor-like screening model-real solvent succeededin describing the main features of the interactions between the keratinderivatives and the solvents used. The process analysis performedon several alternatives showed that the process is technically andeconomically viable at the industrial scale, the costs being stronglydependent on the excess of both the solvent used to dissolve keratinand the water added for its regeneration. Several options to improvethe process and reduce the costs are discussed.