Method for tanning leather without pickling

Abstract

The invention discloses a method for tanning leather without pickling. The method is characterized by comprising the following steps (A) deliming: deliming limed hide-cut naked hide in the presence of an ammonium-free deliming agent, wherein the using amount of the ammonium-free deliming agent is 0.8-3 percent of the hide weight; (B) softening: softening in the presence of a softening enzyme, wherein the using amount of the softening enzyme is 0.3-1.5 percent of the hide weight; (C) chrome tanning: performing chrome tanning treatment on the softened naked hide in the presence of a non-prickled chrome tanning agent, wherein the pH value at the initial stage of tanning treatment is 6.5-8.5, the liquid ratio at the initial stage of tanning treatment is 30-50%, and the non-prickled chrome tanning agent is an anionic chrome tanning agent; and (D) finishing: performing post-finishing on tanned blue wet leather to obtain finished leather. By applying the non-pickling chrome tanning method, the emission of salt in leather making, pickling and chrome tanning waste water is avoided effectively, the emission of chrome in the tanning waste water is reduced, and the product quality of the finished leather is enhanced at a certain degree.

Description

technical field [0001] The invention relates to a method for chrome tanning leather without pickling, belongs to the technical field of clean leather manufacturing, and is a main procedure in leather production and processing. Background technique [0002] The traditional tanning production process uses water as the medium to process raw hides and skins into finished leather through chemical, physical and mechanical actions. [0003] The chemical treatment process in leather production is carried out in a wide pH range, such as: soaking, dehairing, liming, deliming, softening, pickling, tanning, retanning, neutralization, dyeing, fatliquoring, acid Fixing, etc., repeated liming-deliming; pickling-alkali extraction; neutralization-acidification and other processing processes, repeated acid, alkali, and salt actions make the salt content in tannery wastewater very high. At the same time, repeated acid, alkali, and salt actions also cause the cortex to be damaged to varying de...

AI Technical Summary

Problems solved by technology

[0006] The technical problem solved by the present invention is to provide a clean and simple non-pickling chrome tanning method for tanning in view of the deficiencies of the existing pickling and tanning techniques in the production process of tanning. application, as well as the corresponding adjustment and balance of process technology, to realize a method of tanning without pickling in tanning, thereby effectively avoiding the discharge of salt in tanning and tanning wastewater, reducing the discharge of chromium in tanning wastewater, and at the same time The discharge of waste water and other pollutants can also be effectively reduced, and the product quality of finished leather can be improved to a certain extent.