Depilating composition for less thiolase process and the piling depilation method therewith

Abstract

The depilating composition for less thiolase process and the piling depilation method therewith features that leather blank in 100 portions, proteinase in 0.1-0.6 portion, sodium sulphide in 0.1-0.8 portion, sodium chloride in 0.1-3 portions, surfactant 0.1-1 portion and hydrogen peroxide in 0-5 portions are dissolved or dispersed in water of 7-15 portions while adding rice bran in 1-4 portions and kaolin in 0.5-3 portions to form paste mixture; and the leather blank is then brushed manually to make the mixture adhered onto the inside of the leather blank, piled with inside to inside in hot room at 15-35 deg.c for 20-30 hr, and depilated manually after the hair becomes loose. The said depilating process has high depilating effect, and can produce soft plumpy and light-colored leather with high strength. In addition, the said process has less sulfide pollution and its effluent has low COD and low BOD5.

Description

1. Technical field [0001] The invention relates to a sulfur-less enzyme hair removal composition and a stacking hair removal method thereof, belonging to the technical field of leather engineering. 2. Background technology [0002] Traditional animal skins such as sheepskin, cowhide and pigskin are mainly depilated by the soda sulfide method. The sheepskin is made of soda sulfide and lime into a paste and applied to the meat surface of the skin. After stacking for a certain period of time, the hair is pushed manually; Pigskin and the like are destroyed in a water bath with soda sulfide and lime in a drum. Therefore, there are serious pollution problems, including sulfide, lime, and a large amount of COD and BOD produced by the dissolution of wool 5 and SS. [0003] At present, tanneries generally adopt the traditional ash-alkali method for hair removal. This method has good hair removal effect, stable quality, and mature technology, but it will produce a large amount of de...

AI Technical Summary

Problems solved by technology

Among them, the amount of 1398 enzyme is greater than 0.4%, and the amount of sodium sulfide is 0.5% (Wang Jiangen, Zhang Zhongyu, Chen Chaoying, etc. Research on depilation technology with less sodium sulfide enzyme. "China Leather", 2001, 30 (5): 29-32), this The operation of this method is more loaded down with trivial details, and the consumption amount of sodium sulfide is also higher, and has also brought the pollution of phenolic substance, and the hair that takes off is difficult to recycle.

[0005] Chinese patent 90101445.1 "Ash Enzymatic Hair Removal New Technology Thoroughly Solving Sulfur Pollution", 88103066.X "Triisopropanolamine Hair Removal New Technology" and 85102770 "Triethanolamine Hair Removal Technology" all use other chemical substances instead of sulfide hair removal, only The first patent is to use protease to remove hair under the action of lime to completely replace sulfide and solve the problem of sulfur pollution. However, it is difficult to control the process, and it is prone to problems of incomplete hair removal or rotten surface

In the latter two patents, organic amines are used instead of sulfides for hair removal, but there are pollution problems and even toxicity problems of organic amines

There are no patent reports on low-sulfur assisted enzyme hair removal technology