In India, scientists at the Central Leather Research Institute have developed a biobased copolymer matrix that improves the efficiency of chromium use in leather tanneries—reducing the amount of the toxic chemical that ends up in the environment.
According to Dr. J Kanagaraj, senior principle scientist at CLRI, over 90% of all leather tanneries worldwide use chromium, which makes leather non-perishable. Approximately 70% of chromium-containing tannery chemicals are adsorbed during treatment, leaving the remaining 30% as pollutants.
Kanagaraj’s team developed a biobased copolymer matrix that spreads chromium across the pores in the leather, fixing it at active sites. The remaining chromium is minimal, and can be treated with bacteria. “This compound is not only environment friendly, it also produces finer quality of leather,” Kanagaraj tells New India Express. “The colour properties of the leather become richer and more uniform, the softness increases, the thickness of the leather is increased and the product is more physically and thermally stable.”
The method can also be applied to de-fleshing, trimming, and pre-tanning. The results were published in a recent issue of the Royal Society of Chemistry.