Life cycle assessment insights into nanosilicates-based chrome-free tanning processing towards eco-friendly leather manufacture

Abstract

Chrome tanning system has been faced with great challenges from potential environmental and human health risks and environmental pressures in the leather industry. The development of chrome-free tanning system towards eco-friendly leather manufacture is the main strategy to solve them from the source. However, appropriate assessments of the physical and environmental properties of a new tanning process remain challenging. In this work, we compared the physical performances and environmental impacts of two nanosilicates-based chrome-free combination tanning systems with conventional chrome tanning system in practical fur leather processing. The objective of this study was to obtain comprehensive insights into the nanosilicates-based chrome-free combination tanning systems from both technical and environmental perspectives. All fur leathers possessed similar and integrated fleece structures, ensuring high glossy and flexibility of final fur leather articles. Tara tannin-Zeolite (TA-ZE) combination tanning system was chosen as the most promising one for manufacturing garment leather articles. The resultant leathers were endowed with favorable physical properties (e.g., tear strength of 15.9 N, elongation at break of 42.3%, shrinkage temperature of 98.6 °C) and no restricted Cr(VI) and free formaldehyde. Life cycle assessment (LCA) results revealed that the TA-ZE combination tanning system exhibited better environmental impacts than other options. The main novelties included the contribution to avoiding the use of high-risk tanning chemicals by presenting a better technical and environmental alternative in the leather processing and the application of LCA to environmentally evaluate the leather processing. We envision these findings can offer comprehensive insights into emergent chrome-free combination tanning systems for designing and rationalizing feasible fur leather processing towards eco-friendly leather manufacture.