Deep eutectic solvent-mediated one-step eggshell removal and anti-felting of wool

The sheep lice eggshells and felting are both important problem in wool industry. Deep eutectic solvents (DES) are a class of eco-friendly and low-cost solvents that are used in various fields including the anti-felting of wool but not in the eggshell removal. In this study, the simultaneous removal of wool scales and lice eggshells using [ChCl:Urea] was achieved by optimizing the formula and condition. Satisfactory eggshell removal (80.0%) and anti-felting rates (22.7%) had little effect on the mechanical strength of the wool (12.1%). The mechanism of the beneficial effects was studied using scanning electron microscopy and Fourier-transform infrared spectroscopy. The loose structure of protein cement is conducive to the penetration of DESs to achieve complete disintegration and dissolution. In contrast, the dense wool structure prevents DESs from penetrating the interior and only removes the surface scales. In addition, dissolution of eggshells by DES also helps in its removal. To our knowledge, this is the first report of DES-mediated one-step eggshell removal and anti-felting of wool. Through economic and environmental effects analyses, DES-based technique exhibits a more promising potential for industrial applications. This work not only has significant application prospects in the wool industry, but also the application scenarios of DESs.