May 1,3,5-Triazine derivatives be the future of leather tanning? A critical review

• Published in: Environmental pollution (1987) 2024-03, Vol.345, p.123472-123472, Article 123472
• Main Authors: Facchin, Manuela, Gatto, Vanessa, Samiolo, Riccardo, Conca, Silvia, Santandrea, Domenico, Beghetto, Valentina
• Format: Article
• Language: English
• Subjects: Aldehyde-free tanning; Chrome-free tanning; Phenol-free tanning; Pickle-less tanning; Triazine tanning agents
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2024.123472

Leather is produced by a multi-step process among which the tanning phase is the most relevant, transforming animal skin collagen into a stable, non-putrescible material used to produce a variety of different goods, for the footwear, automotive, garments, and sports industry. Most of the leather produced today is tanned with chromium (III) salts or alternatively with aldehydes or synthetic tannins, generating high environmental concern. Over the years, high exhaustion tanning systems have been developed to reduce the environmental impact of chromium salts, which nevertheless do not avoid the use of metals. Chrome-free alternatives such as aldehydes and phenol based synthetic tannins, are suffering from Reach restrictions due to their toxicity. Thus, the need for environmentally benign and economically sustainable tanning agents is increasingly urgent. In this review, the synthesis, use and tanning mechanism of a new class of tanning agents, 1,3,5-triazines derivatives, have been reported together with organoleptic, physical mechanical characteristics of tanned leather produced. Additionally environmental performance and economic data available for 1,3,5-triazines have been compared with those of a standard basic chromium sulphate tanning process, evidencing the high potentiality for sustainable, metal, aldehyde, and phenol free leather manufacturing. [Display omitted] •1,3,5-triazine derivatives are a valid alternative systems to metal, aldehyde, syntan tanning for regulatory restrictions.•1,3,5-triazine derivatives tanning agents are safer than Chromium and Glutaraldehyde for health and environmental impacts.•1,3,5-triazines derivatives are a green solution as tanning agents.•Leather tanned by 1,3,5-triazine have Ts up to 90 °C.