Extracting and Studying the Factors Affecting the Tanning Material in the Garad Pods

Abstract

In this study the chemical structure of Garad tan pods (acacia – nilotica) were determined and investigated. It was found that Garad tan is a polyphenol type of structure and consequently it has an antiseptic effect, it is also used as pretaning and retaning agent.
 Garad pods need to be disintegrated and ground into fine grains of very small diameter. In its powder form it cannot be used in tannage as the grains may block the sewage, hence, it has to be leached, concentrated and spray dried.
 The factors that affect leaching of the tannins from Garad pods were studied, there are: Temperature, solvent to solid ratio, degree of mixing and time were specified and factorial experiments were designed to study the effect and significance of these factors. The levels of these factors were (30 and 50°C), (1:5 and 1:7), (with and without) mixing and (25 and 50) minutes respectively. All these factors were found to be very significant.
 Having determined the optimum factors their levels trials were carried out at the following levels: 
 Temperature: 50°C
 Solid to solvent ratio: 1:7
 Degree of mixing: With mixing
 Time: 50 minutes
 The trials made at these conditions were found to be efficient with high yield of the extract. The extract produced was concentration which makes it ready for use in pertannage or retannage or for spray drying to powder.

Tanning capacity of Tessmannia burttii extracts: the potential eco-friendly tanning agents for the leather industry

“…Since vegetable tannins are anions in nature [8], they react preferably with amino groups, either protonated or unprotonated rather than carboxyl groups of the collagen [9]. Although several studies have reported the tanning capacity and interaction mechanism of the extract from different plant species [9][10][11][12][13], they represent infinitesimal fraction of available potential of the vegetable tannin sources. Therefore, there is huge reservoir of unexploited plants from different parts of the world with significant amount of tannins that need to be studied for their chemistry as well as their potential industrial applications including in the leather industry.…”