Reducing the amount of tanning materials passing into wastewater in post-tanning processes

This research was carried out in order to detect and reduce the amount of the tanning material passing from leather into the float during post-tanning processes. In the research, the possibility of reducing the amount of unbound or weakly bound tanning materials, passing from leather into wastewater during post tanning processes, by forming a complex with a second tanning material used in a new float was examined. The feature of mineral tanning materials that enables them to form a complex with vegetable tanning materials was used for this purpose. It was proved that the amount of the mineral tanning material passing into wastewater during post tanning processes was reduced to some extent with vegetable tannin application after mineral main tannage, while the amount of vegetable tanning material passing into wastewater could be reduced in significant amounts of approximately 85% with mineral tanning material application after vegetable tannage