reProLeather: Regenerating Bio-based Leather from Leather Waste

Leather production generates wastewater and harmful chemical residuals, such as chromium VI. HKRITA has developed a recycled leather system that separates, categorises and recycles post-consumer leather products into useful raw materials for the manufacturing of new products. It is carried out in two steps, beginning with shredding a whole post-consumer leather product into pieces until leather fibres of high purity are obtained, and removing free chromium by transforming it into a soluble salt or complex compound. Then the separated leather fibres react with bio-based binders such as sugar or protein under mild conditions, and collagen fibres become interconnected and form a new leather. Regenerated leather obtained with such a novel bio-based approach is water-resistant and biodegradable, resulting in a ‘virtuous circle’ for leather recycling.