Thermal Characterization and Pyrolysis of Waste Leather Treated with CoCl₂ And MnC₂

Abstract

Leather tanned with different agents was pyrolyzed in the presence of CoCl2 and MnCl2 catalysts. A bovine leather sample tanned with two inorganic tanning agents (chromium and titanium salts) and two organic tanning agents (glutaraldehyde and methylacrylic resin) has been used in this study. The samples were soaked in solutions of CoCl2 or MnCl2 of known concentration. The influence on decomposition temperature and the resultant pyrolysis compounds has been evaluated by using thermogravimetric analysis (TG/DTG) and flash pyrolysis (Py-GC/MS). A multivariate analysis has been applied to the pyrolysis products obtained confirming the effect of the catalyst treatment on leather, specifically on samples tanned with organic agents. According to the results, CoCi2 (higher Lewis acidity) shows a greater influence than the MnCI2 (lower Lewis acidity). The results indicate that the presence of chlorides affects the nature of the pyrolysis products, increasing the yield of the aromatic compounds in all the samples, thus improving the added-value of the volatiles. These catalysts reduced slightly the decomposition temperature.