Mechanisms of Zn(II) binded to collagen and its effect on the capacity of eco-friendly Zn-Cr combination tanning system.
The eco-friendly combination tanning process has been developed to reduce chromium in existing researches, which is based on zinc tanning agents. This can be considered as a less-chrome substitute for current tanning process. To gain deeper understanding of the binding mechanisms of zinc-collagen interaction, which are affected by tanning pH, experiments have been carried out. Analysis in this paper reveals how chemical bonds from the collagen's main function groups combine with zinc. XPS and NIR data was analyzed for further understanding of where the zinc binding sites lie on collagen fibers at different pH. The results indicate that high pH is helpful to amino-binding sites while low pH promotes carboxyl-binding sites on collagen fibers. Furthermore, from the effect of Zinc-chrome combination tanning, we can see that the new method reduces the chromium dosage in tanning process compared to the conventional chrome tanning method.
College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, PR China; College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, PR China.
Shan
S
Cao
Room L1.42 Gorlaeus Laboratory, Leiden, The Netherlands.
Bing
B
Liu
College of Material Science and Chemical Engineering, Tianjin University of Science and Technology, Tianjin, 300457, PR China.
Baozhen
B
Cheng
College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, PR China.
Fuping
F
Lu
College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, PR China.
Yanping
Y
Wang
College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, PR China. Electronic address: cs1988@foxmail.com.
Yu
Y
Li
Binding sites; Chromium; Combination tanning; Functional groups; Zinc