Innovative aerogel transforms tannery waste into leather industry resource

In a significant leap forward for sustainable waste management, a team of scientists led by Shuang Liang and Xuechuan Wang from Shaanxi University of Science and Technology have developed an aerogel made from chitosan (CS) and sodium carboxymethyl cellulose (CMC–Na) that addresses the dual challenge of tannery wastewater treatment and resource utilization. The aerogel, prepared via a sol-gel method, demonstrates exceptional adsorption capacities for Cr(III), Al(III), and Zr(IV) ions, commonly found in tannery effluents.

The study, published in the Journal of Bioresources and Bioproducts, reveals that the adsorption process aligns with the Langmuir isotherm adsorption model and pseudo-second order kinetics, achieving maximum fitted adsorption capacities of 250.0, 111.1, and 100.0 mg/g for Cr(III), Al(III), and Zr(IV), respectively. Innovatively, after adsorbing metal ions, the composite materials were repurposed as re-tanning agents in the leather industry, enhancing the shrinkage temperature of leather by up to 5°C.

This research stands out for its circular economy approach, which not only mitigates the environmental impact of heavy metals from tannery wastewater but also leverages waste adsorbents in the production of leather, thereby closing the loop on waste and adding value to the industry. The method bypasses traditional chemical desorption, avoiding secondary pollution and the complexities of metal desorption reuse processes.

The findings underscore the potential of biomass-based materials in creating sustainable solutions for industrial waste management. As the leather industry grapples with environmental sustainability and the efficient use of resources, this study offers a promising path forward, highlighting the importance of interdisciplinary research in material science and environmental engineering.