Poster
Abstract
Research summary supplied by the authors
Currently, minimizing the environmental impact of tanning processes is the goal of many tanners, which have forced the leather industry to develop tanning systems based on natural products. Biomass- derived polyaldehyde or vegetable -aldehyde combination tanning is the c urrent research hotspots . While, the usage of these tanning materials may result in high organic load in the effluent leads to high biological and chemical oxygen demand. Sparked from vegetable tanning, employing excess by - products of biomass glycerol and glycidol to produce high value-added chrome-free tanning agents will be in great significant. In this paper, a series of hyperbranched polyglycidyl ( HPG) with different hydroxyl group , various average-molecular weights and molecular weight distribution have been developed by cationic or anionic ring-opening polymerization of glycidol. The denaturation temperature of the wet -white leather as well as biological and chemical oxygen demand of effluent have been measured. The results show that the denaturation temperature of the wet-white leather significantly improved. The highest den aturation temperature can reach 115.6 ℃ by employing 5% H PG-C4. Compared to hydroxyl group content, average molecular weight and its distribution of HPG play a more dominant role in improving the denaturation temperature of the wet-white leather. In addition, compared to control trial, the chemical oxygen demand and biological oxygen demand of effluent tanning by HPG can reduce by nearly 1/ 5 and 1/3, respectively. Therefore, the use of HPG benefits to the complete elimination of chrome pollution and greatly reduce the biological and chemical oxygen demand of the effluent.