METHOD OF PRODUCING GRAPHITE BORON NITRIDE Russian patent published in 1999 - IPC

FIELD: methods of graphite boron nitride production. SUBSTANCE: method includes preparation of mixture of initial components containing magnesium, boron oxide and 10-20 wt.% of specific addition selected from the series including product of synthesis of born nitride, boron nitride or magnesium oxide; placing of prepared mixture of components into shell from material of specified addition with thickness of its layer mainly equalling 3-5 mm; heat treatment of prepared mixture under conditions of self-propagating high-temperature synthesis under nitrogen pressure of 8-10 MPa; removal of product by treatment of synthesis product in mineral sulfuric acid of 10-26% concentration. In this case, additionally introduced into nitrogen may be ammonia or hydrogen in the amount not in excess of 10 vol%. product of synthesis of boron nitride has not more than 30 wt.% of graphite boron nitride. EFFECT: simplified process and increased yield. 5 cl, 1 tbl