METHOD FOR PRODUCING ULTRADISPERSED BORON NITRIDE Russian patent published in 1997 - IPC

FIELD: inorganic chemistry. SUBSTANCE: mixture of aqueous solution of boric acid and carbamide is decomposed in flow of low-temperature nitrogen plasma in presence of hydrocarbon (natural gas or propane), followed by separating desired product from dust-and-gas mixture. Process is conducted at a molar ratio of 1 mole boric acid to at least 2, preferably 2-5 moles carbamide. Hydrocarbon is taken in 5- to 12-% excess in relation to amount stoichiometrically required for water decomposition. Boron nitride yield is in excess of 99%, impurities content therein being less than 1%. EFFECT: simple method for producing cheap, ultrafine, good-quality boron nitride. 4 cl, 1 tbl