The method of processing of raw hides
(57) Abstract:The method refers to the leather industry and can be used when conducting otlochno-ash processes in leather production from various raw materials. The method includes the processing of raw hides composition containing a polyethylenepolyamine, calcium hydroxide, sodium sulfide and nonionic surfactants. The technical result is to increase the quality of the skin and decrease in the contents of amino compounds in the wastewater. table 1. The invention relates to the leather industry and can be used when conducting otlochno-ash processes in leather production from various raw materials.A method of processing leather raw material by soaking and ashing composition containing thiourea dioxide, surfactants and dimethylamine in the presence of calcium hydroxide in the amount of 2.5% by weight of raw material (patent Austria, 381952, CL 14 With 1/06, 29.12.86).The disadvantage of this method is the relatively large duration ashing 24 hours and incomplete removal of the skins of the residues of hair.The closest analogue of the proposed technical solution is the method of processing of raw hides by soaking in aqueous democratic amines 73,5-75,0Sodium hydroxide 20,0-22,0Polyacrylamide with a molecularmass 200 thousand to 500 thousand 4,5-5,0moreover, the composition is injected directly into the surfactant solution after soaking in the amount of 5-15% by weight of the raw materials, as well as aliphatic amine or a mixture of aliphatic amines using 35% monomethylamine or 33% dimethylamine, or a mixture 1:1 (SU 995515 And CL 14 With 1/04, 30.09.83].The disadvantage of this method is the use of a substantial amount of aliphatic amines (3.5 to 10% by weight of raw materials), which pollute the waste water aminecontaining compounds. In addition, this solution does not allow sufficiently loosen the structure of the dermis, resulting in hard leather.The technical result of the invention is to improve the quality of hides and decrease in the contents of amino compounds in the wastewater enterprises.This technical result is achieved in that in the method of processing of raw hides by soaking and ashing composition comprising aliphatic amine and calcium hydroxide, in the presence of nonionic surfactants, the composition further added sodium sulfide as aliphatic amine used poliehtilenpoliamina the wt.%:Preteenpreteen 8,5-10,5Calcium hydroxide 34,0-38,0Sodium sulfide 34,0-38,0Nonionic surfactants of 15.5-21,5A distinctive feature of the proposed method is that the introduction of the ash solution polyethylenepolyamine contributes to the improvement of the separation structure of the dermis to the more subtle elements, and its alkaline nature allows processing at optimum pH values of 12.6-12,8.The use of sodium sulfide and calcium hydroxide in the ratio of 1:1 contributes to the production of fine-dispersed system with a particle size of 2-10 μm, which are easily and quickly penetrate to the active centers of the collagen molecules and provide maximum loosening of the structure of the dermis, which allows you to get soft, supple skin.As a result of joint action of alkaline reagents, including polyethylenepolyamine, in the presence of surfactants is a higher degree of degreasing, especially when handling raw pork.Introduction polyethylenepolyamine less than 8.5 wt.%, calcium hydroxide and sodium sulfide is less 34,0% by weight of each is not possible to achieve optimal separation of the structure of the dermis to obtain skins with high explota the Tria more 38,0 wt.% each is impractical due to excessive razvlechenija dermis and the possibility of the emergence of tbsistuste, as well as for environmental reasons.The polyethylenepolyamine (Pepa) is produced by the method of condensation of Monomeric ethylenimine in the presence of catalysts. The probes are manufactured in accordance with THE 2413-375-00203447-99 and is a yellow liquid without mechanical impurities.As the nonionic surfactants used neonols (TU 2483-077-05766801-98), prefocal (Germany), etc.The skins of bovine animals, swine raw materials or sheepskin are: soaking off over 4.5-6.5 h at W.to. 1.5 to 2.2 and a temperature of 30-35C. After draining the bath produce liming materials at a temperature of 38-40C and W.to. 1,8-2,2 within 16-20 hours following composition, wt.%: the polyethylenepolyamine 8,5-10,5, calcium hydroxide 34,0-38,0, sodium sulfide 34,0-38,0, nonionic surfactants of 15.5-21.5 in. The flow rate of 6-11% by weight of raw materials. Further processes and operations carried out by known technologies.Composition for ashing raw material is prepared as follows.In a container equipped with a mixer, with a stated ratio of the components loaded calcium hydroxide and sodium sulfide, then with constant stirring add the polyethylenepolyamine and a surfactant.Example 1. Cattle skin after soaking subjected to liming at a temperature of 35C and W.to. 2,0 within 18 cha is ulfig sodium 38,0Nonionic surfactants 15,5The flow rate of 8% by weight of raw materials. Further processes and operations carried out by the method of production of leather for the uppers natural outer surface.Example 2. Pork raw after soaking process as in example 1, but the liming produce the following composition, wt.%:The polyethylenepolyamine 9,5Calcium hydroxide 36,0Sodium sulfide 36,0Nonionic surfactants 18,5Further processes and operations are performed according to the method of manufacturing elastic leathers for the uppers.Example 3. Sheepskin, after the soaking process, as in example 1, but the liming produce the following composition, wt.%:The polyethylenepolyamine 10,5Calcium hydroxide 34,0Sodium sulfide 34,0Nonionic surfactants 21,5Further processes and operations carried out by the method of production of leather for the uppers.Example 4. Cattle skin after soaking process as in example 1, but the liming produce the following composition, wt.%:The polyethylenepolyamine 8,0Calcium hydroxide 39,0Sodium sulfide 39,0Nonionic surfactants 14,0Example 5. Pork raw after Otman 11,0Calcium hydroxide 33,5Sodium sulfide 33,5Nonionic surfactants 22,0Quality indicators received skin compared to skin on the prototype presented in the table.Using the proposed method can reduce the pollution of waste water aminecontaining compounds and get ready skin with high performance properties. The method of processing of raw hides by soaking and ashing composition comprising aliphatic amine and calcium hydroxide, in the presence of nonionic surface-active substances (surfactants), characterized in that the composition further added sodium sulfide as aliphatic amine used polyethylenepolyamine and surfactant are injected directly into the composition in the following ratio, wt.%:The polyethylenepolyamine 8,5-10,5Calcium hydroxide 34,0-38,0Sodium sulfide 34,0-38,0Nonionic surfactants of 15.5-21.5 in
FIELD: fur industry.
SUBSTANCE: fur fells are treated with aqueous solution of nonionic surfactant and antiseptic, which is aqueous dispersion of acrylic copolymer with dimethylformamide at ratio (1.0-1.1):(5.0-5.1), respectively.
EFFECT: improved physico-mechanical characteristics of fur fells and improved environmental condition.
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