Method for preparing chromium-containing hydrotalcite nano tanning agent by using chromium tanning waste liquid

Abstract

The invention discloses a method for preparing a chromium-containing hydrotalcite nano tanning agent from chrome tanning waste liquid, and aims to solve the problem that the chrome tanning waste liquid pollutes the environment. According to the technical scheme, the method for preparing the chromium-containing hydrotalcite nano tanning agent by utilizing the chrome tanning waste liquid comprises the following steps: utilizing the chrome tanning waste liquid, adopting a coprecipitation method, and controlling the molar ratio of divalent metal ions to chromium ions to prepare the chromium-containing hydrotalcite nano tanning agent. The chromium-containing hydrotalcite nano tanning agent prepared by the method has excellent tanning performance, the shrinkage temperature of tanned crust leather is greater than or equal to 85 DEG C, the tensile strength and the tearing strength are both improved, and the biodegradability of tanning waste liquid using chromium-containing hydrotalcite is improved.

Description

technical field

[0001] The invention belongs to the field of leather tanning agents, and in particular relates to a method for preparing chromium-containing hydrotalcite nano-tanning agents by utilizing chrome tanning waste liquor. Background technique

[0002] Chrome tanning agents are widely used in the leather industry because of their excellent tanning properties, but the chrome tanning waste is harmful to the environment, so the effective use of chrome tanning waste is one of the research hotspots in the tanning industry. The composition of chrome tanning waste liquid is complex, containing a large amount of heavy metal Cr 3 + , and contains a variety of inorganic ions and organic acids, such as SO 4 2- , Cl - 、Na + 、K + , formic acid, acetic acid, etc., as well as protein decomposed from skin collagen, animal fat, etc., are difficult to process and costly.

[0003] Hydrotalcite is a kind of layered double hydroxyl metal hydroxide (LDH) whose main layer is positi...