The invention provides a method and device for preparing high-purity
boron tribromide (BBr3) from
boron carbide used as a
raw material. The method comprises the following steps: vaporizing industrial grade liquid
bromine through a
vaporization kettle, introducing the
bromine vapor into a
drying chamber under the guidance action of a trace of
nitrogen gas, removing
moisture by means of
anhydrous calcium chloride, feeding into a reaction furnace, and reacting with
boron carbide particles at a
reaction temperature of 650-850 DEG C to obtain
boron tribromide containing impurities, dust and colors; performing ash removal on the
boron tribromide through an ash blocker, removing residual
bromine and iron ions by means of naphthol in a
distillation kettle, and distilling to obtain white
boron tribromide; and rectifying through a rectification
tower, and removing high
boiling point and low
boiling point impurities to obtain a boron
tribromide product of which the purity is greater than 5N, wherein the boron
tribromide rectifying temperature is 120 DEG C, and the
reflux ratio is 2-3.The high-purity boron tribromide preparation device provided by the invention is composed of the
vaporization kettle, a dryer, the reaction furnace, the ash blocker, a condenser, the
distillation kettle (for iron and bromine removal), the rectification
tower and a finished product kettle. The purity of the boron tribromide produced by the invention can be up to 5N or above; and the method and device are low in cost and high in efficiency, and can realize industrial
continuous production.