Sustainable Routes for Wool Grease Removal Using Green Solvent Cyclopentyl Methyl Ether in Solvent Extraction and Biosurfactant Wool Protein Hydrolyzate in Scouring

Abstract

This work focuses on introducing new sustainable chemicals in the wool grease removal processes by aiming to understand the effect of an eco-friendly solvent, cyclopentyl methyl ether (CPME), in solvent-based wool grease extraction and, in addition, the impact of the wool protein hydrolyzate (WPH) as a biosurfactant derived from green hydrolysis in the wool scouring process. In the green solvent extraction process assisted using solvent CPME, the effect of CPME on grease extraction and the presence of four primary fatty acids were evaluated and compared with conventional solvents. The quantity of grease extracted using green solvent CPME was more significant than the conventional solvents. An extraction using green solvent CPME resulted in 11.95% extracted wool grease, which is more when compared with 8.19% hexane and 10.28% diethyl ether. The total quantity of four fatty acids was analyzed and found to be ~15% for CPME ~17% for Hexan compared with ~20% for commercial lanolin. FTIR of CPME-extracted wool grease exhibits primary and distinguishing bands similar to pure wool grease. Wool cleanliness efficiency was morphologically analyzed using SEM, resulting in no fiber degradation or surface alterations. These analyzes indicated that CPME has the potential to be claimed as an effective green alternative to conventional solvents for the extraction of grease and fatty acids. In a sustainable scouring process, WPH was used as a biosurfactant, an eco-friendly alternative. Furthermore, scouring process parameters such as temperature, material-to-liquor ratio, and WPH concentration were optimized for efficient scouring. The wool samples scoured using WPH biosurfactant exhibited nearly similar whiteness and yellowness and washing yield compared with Biotex AL. These results comply with SEM analysis, which showed that WPH-scoured wool had an intact scale structure, a smooth fiber surface, and no wool grease layer. At optimum conditions, WPH reduced the residual grease content of Sopravissana wool from 22.29% to 0.30%, comparable to the commercial biosurfactant Biotex AL. Compared with conventional wool grease removal processes, the green solvent CPME and biosurfactant WPH were considered viable, sustainable, and environmentally friendly alternatives.