METHOD OF OBTAINING KERATIN MONOPRODUCT (OPTIONS) Russian patent published in 2019 - IPC C08H1/06 A23K10/26 

FIELD: processing and recycling of waste.

SUBSTANCE: invention relates to the field of processing animal waste to obtain a keratin monoproduct intended for use in veterinary medicine, medicine, cosmetology, biotechnology, food industry, and also as a protein feed additive to the basic diet of animals and birds. In both variants of the implementation of the original keratin-containing material is soaked for 4–6 h in a solution containing 1.0–7 % hydrochloric acid and 0.1–0.3 % hydrogen peroxide when the LR liquid ratio of 12–15, followed by washing with deionized water to neutral pH values, spend from 1 to 4 consecutive processing cycles, each of which is a treatment of keratin-containing semi-finished product in a solution containing 0.05–2.5 % sodium hydroxide and 0.1–1.0 % hydrogen peroxide for 8–12 hours at a temperature of 28–32 °C at LR from 6 to 10, precipitating keratin from the reaction mixture for 0.5–1.0 h with 7–10 % hydrochloric acid and rinsing the precipitate with deionized water until neutral pH. To obtain a liquid keratin monoproduct (in the first embodiment), upon completion of the treatment cycles, the product purified from non-keratic impurities is redissolved in 0.1–1.0 % sodium hydroxide solution for 4–6 h, at occasional stirring, homogenized to a particle size of 180–220 microns and filtered, and then its pH is stabilized to 6.7–7.3 using a 0.1–1.0 % solution of sodium hydroxide and bring the dry residue to 3.0–15.0 % using the same solution, to obtain a monoproduct containing 95–98 % keratin, to which a preservative is added before packaging. To obtain the dry form of the keratin monoproduct (according to the second variant), after the completion of the treatment cycles, the sediment purified from impurities is redissolved in 0.1–1.0 % sodium hydroxide solution, keeping it for 4–6 hours at periodic stirring, a preservative is added and the resulting volume of product is poured into cuvettes to a layer thickness of 1–2 cm. Product is then lyophilized using stepwise dehydration in the range of cryoscopic temperatures from -30 to -60 °C for 24–36 h, bringing the moisture content in the product to 0.5–5.0 %, then the product is gradually heated to a temperature of up to 10–20 °C and crushed to a powder with a particle size of 1–3 mm, and then packed.

EFFECT: improvement of technological processes made it possible to increase the solubility of the initial keratin-containing raw materials and increase the yield of native keratin to 95–98 wt% with a mass fraction of dry substances in monoproduct 5–15 wt%, id est ensure the achievement of the technical result – the possibility of obtaining a single product with a high environmental friendliness of its production.

2 cl, 2 ex