Quebracho - Oxazolidine Combination Tanning for Leather Making

Abstract

Different markets require the manufacture of chrome-free leather to have comparable properties to chrome tanned leather such as feel, fullness, softness, and hydrothermal stability. The deep interest in clean technologies and stringent norms set by regulations; have led the tanners to increase their efforts to develop chrome free tanning agents. Combination tannages are considered as suitable alternatives for a chrome-free tanning system. Among the innumerable combination tannages that are currently being exploited are vegetable tannin/oxazolidine combinations as the most promising options. In this study, organic combination tanning process based on quebracho powder (Schinopsis balansae) and oxazolidine for the production of upper leathers is presented.  Quebracho powder has been utilized in the combination tanning system with oxazolidine. Quebracho tanned leathers from goat skins used as control leathers. It has been observed that Quebracho - oxazolidine combination tanning which employs 20% Quebracho and 5% oxazolidine provides a shrinkage temperature of 102oC, which is 18oC more than the control leathers. The characteristics of the leathers indicate that the Quebracho -oxazolidine combination system provides leathers with good organoleptic properties and comparable strength properties. The experimental tanning system provides significant reduction in the discharge of total dissolved solids in the wastewater. The leathers have been further characterized for chemical analysis. The leathers obtained from the combination system are lighter in color compared to control leathers. The manufacture of upper leathers using combination of Quebracho and oxazolidine suggest that this tannage is a promising alternative to traditional chrome tanning.