Salmi, O.; Gelosa, S.; Rossi, F.; Masi, M. A Circular Approach to Finished Tanned Leather: Regeneration by Cryogenic Technology. Materials2023, 16, 6166.
Salmi, O.; Gelosa, S.; Rossi, F.; Masi, M. A Circular Approach to Finished Tanned Leather: Regeneration by Cryogenic Technology. Materials 2023, 16, 6166.
Salmi, O.; Gelosa, S.; Rossi, F.; Masi, M. A Circular Approach to Finished Tanned Leather: Regeneration by Cryogenic Technology. Materials2023, 16, 6166.
Salmi, O.; Gelosa, S.; Rossi, F.; Masi, M. A Circular Approach to Finished Tanned Leather: Regeneration by Cryogenic Technology. Materials 2023, 16, 6166.
Abstract
Finished tanned leather are usually covered by a thin polymeric layer. This layer has the scope to change the morphological aspect of the last leather layer, as well as to improve the impermeabilization properties. Often, the finished product is refused by the final client and tanneries must restore significant quantity of materials. Therefore, it is very important to remove this finished polymeric layer, to recover the underneath tanned leather and to predispose it to a new finishing. The bonding between the polymeric film and leather is so strong that, today, only a blade shaving process can perform this separation at the expenses of also removing a layer of tanned leather and consequently reduce the leather thickness. Here, a novel separation method was developed, based on the significant difference in the dilation properties between the tanned hide and the polymeric film at low temperature. The use of cryogenic fluids, in particular the direct application of liquid nitrogen, can freeze the polymeric layer under the glass transition temperature and then inducing a brittle behaviour. The result is an easy separation without any alteration of the tanned leather layer. Thus, the process here developed, allows the reuse of the tanned leather towards a new life in the respect of the circular economy principles.
Keywords
recycle; circular economy; cryogenic removal
Subject
Chemistry and Materials Science, Materials Science and Technology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
