METHOD FOR REMOVING HIGHLY VOLATILE SOLVENT FROM PYROXYLINE POWDER Russian patent published in 2015 - IPC C06B21/00 C06B25/18 

FIELD: chemistry.

SUBSTANCE: method involves removing an alcohol ester solvent by pre-soaking the powder processed in an aqueous medium first at a temperature of 18-22°C for at least 1.0 hour, then in a new portion of water at a temperature of 30-40°C for at least 1.5 hour followed by removing the solvent in a centrifuge first by displacing it from the powder with water spraying at a temperature of 30-40°C at a consumption of fine and medium powders of 2.5-3.5 l/kg and 3.5-5.0 l/kg respectively and squeezing for at least 30 minutes; further the powder is squeezed additionally with no water supplied for at least 15 minutes. The solvent is removed by displacing in batch centrifuges at min. 1,100 revolutions per minute.

EFFECT: method enables producing the homogenous and high-quality low water-alcohol powder and creating state-of-the-art high-efficiency, cost effective and safe processing of all fine and medium powder grades.

2 cl, 1 tbl