SESSION: RecyclingMonPM2-R10 |
10th Intl. Symp. on Sustainable Materials Recycling Processes & Products |
Mon. 21 Oct. 2024 / Room: Dazzle D. | |
Session Chairs: Jie Liu; Fang Wang; Student Monitors: TBA |
The leather industry produces footwear, leather textiles, technical leather, and leather for haberdashery. The main auxiliary chemicals are compounds of trivalent and hexavalent chromium. Stabilization of appropriately treated natural hide, as a by-product of slaughterhouses, is carried out with 80% complex compounds of trivalent chromium, which creates strong coordination bonds with peptide groups of the skin protein - collagen, and thus achieves the desired useful properties of stabilized raw hide - leather. However, the use of chromium also carries risks. In relation to the shoes that we wear, it is important that the shoe material contains only trivalent chromium. According to standards, the maximum content of Cr VI in footwear is 3 ppm and 50 ppm Cr III of leachable chromium. Our contribution looks at both valences of chromium, the conditions under which trivalent chromium is oxidized to its toxic hexavalent form, and its relationship to the footwear and to our health.