The invention discloses a preparation method of electronic-grade
boron trichloride, wherein the preparation method comprises the steps:
chlorine and
hydrogen are introduced into a photocatalytic reactor from the bottom,
phosgene in a
reaction product of a
fluidized bed reactor is decomposed into
carbon monoxide and
chlorine under illumination, the
chlorine and
hydrogen are subjected to a reactionunder
ultraviolet irradiation to generate
hydrogen chloride, and the
hydrogen chloride is extracted from the top of the photocatalytic reactor;
hydrogen chloride is subjected to heat exchange and
vaporization treatment and then subjected to a reaction with
boron powder in the
fluidized bed reactor, and a
reaction product is extracted from the top of the
fluidized bed reactor, then enters a light component removal
tower reboiler for heat exchange and next enters a photocatalytic reactor; a
boron trichloride crude product extracted from the bottom of the photocatalytic reactor enters the light component removal
tower, a product extracted from the top of the light component removal
tower enters a heavy component removal tower
reboiler for heat exchange, and then enters a fractional condenserfor condensation and cooling, and a
liquid phase finally flows back to the light component removal tower; a material of the tower kettle of the light component removal tower enters a heavy component removal tower, and a 6N
boron trichloride product is extracted after the tower top of the heavy component removal tower is condensed by a condenser. The method is simple, reliable, low in
energy consumption, easy to implement and convenient for industrial production.