Method for preparing protein filling material for leather preparation by using leather preparation chromium-containing leftover material as raw material

Abstract

The invention provides a method for preparing protein fillers used for tanning by taking tanning chrome containing scrap materials as materials. The invention is characterized in that chrome containing scrap materials obtained from pieced wet blue are ground, and 100 portions by weight of chrome containing scrap materials are picked up and soaked in an alkali compound solution with the concentration of between 0.1 and 2wt percent, which at least submerges chrome containing scrap materials, for 10 to 48 hours, and the chrome containing scrap materials are drained, and the pretreated chrome containing scrap materials are put in a reaction kettle provided with a stirrer, a thermometer and a reflux condenser, and 6 to 20 portions by weight of alkali compounds and water at least submerging chrome containing scrap materials are added, and the reaction kettle is heated to a temperature of between 50 and 95 DEG C and keeps the temperature for 2 to 20 hours, and the thick liquids with deep color are obtained, and the pH value of the thick liquids is adjusted to between 7 and 10 by an inorganic acid after the thick liquids are cooled, and the thick liquids are filtered, and the filtrate with the solid content of between 10 and 20 percent, which is rich in containing collagen polypeptides, and the filter residues are obtained, and finally the protein fillers for tanning are obtained after the filtrate is condensed and dried; the filter residues are added with 100 to 150 portions by weight of water and has the pH value adjusted to between 2 and 3 by the inorganic acid solution, which obtains a Cr2(SO4)3 green solution used for the chroming agent.

Description

technical field

[0001] The invention relates to a method for preparing protein filler for tanning by taking chromium-containing scraps of leather as raw materials, and belongs to the field of utilization of scraps and waste residue resources in tanning. Background technique

[0002] A large amount of chromium-containing solid wastes—chromium-containing scraps are produced in the process of tanning production. According to reports, only in several major leather-making areas such as South China Sea, Wenzhou, and Xinji, millions of tons of chromium-containing scraps will be produced every year. The main ingredient is collagen, and it also contains about 1.5% Cr 2 o 3 . (Wang Hongru, Lou Jianxin, etc. Discussion on several key issues in the resource utilization of waste chromium, Journal of Shaanxi University of Science and Technology, 2004, 22: 3, 45-49) For a long time, the research on the utilization of chromium-containing scraps has been limited to manufacturing For recyc...