BIRCH BARK PROCESSING METHOD Russian patent published in 2007 - IPC A61K36/13 

FIELD: wood-working and wood chemical industry.

SUBSTANCE: proposed method of birch bark processing includes crushing birch bark in crusher; separation into silver bark and bast: extraction of silver bark using solvent in form of zeotropic mixture of tetrachloroethylene and water; separation of solution from cake; separation of precipitated crystals from mother liquor, washing of crystals with subsequent drying of received product - mixture of three-five triterpene compounds; boiling down of mother liquor to get dry remnant, washing the latter in distilled water with subsequent drying of obtained product - mixture of five-seventeen triterpene compounds; removal of solvent from said cake by mixing it with water and subsequent boiling down of mixture for complete removal of solvent; mixing of said cake with sodium hydroxide and isopropyl alcohol, boiling of said mixture, separation of solution from undissolved sidement, washing of undissolved sediment with distilled water and subsequent drying of obtained product - ligning; distillation of isopropyl alcohol from filtrate, acidification of remaining solution to pH=4.5 - 5.5 and holding it at temperature from minus 5 to 25°C for 0.5-15 h. separation of precipitated sediment from solution, washing of sediment with subsequent drying of obtained product - birch wax; crushing of bast, mixing of bast particles with water, holding of mixture for 1-20 days, separation of sediment from obtained product - sour compound; drying of sediment which can be used as feed additive for cattle and poultry.

EFFECT: provision of complex processing of birch bark.

24 cl, 3 ex, 2 dwg