The invention discloses a preparation method of electronic grade
hydrogen bromide, and the method comprises the following steps: firstly,
bromine is gasified by a preheater, and mixed with
hydrogen toenter a reactor for
catalytic combustion reaction to generate
hydrogen bromide; reaction products are extracted from the top of the reactor and then enter the preheater to exchange heat with the
bromine and then enter a
reboiler to exchange heat with materials in the bottom of a light removal
tower; and the heat-exchanged reaction products enter the light removal
tower after being cooled by a cooler. The
gas phase extracted from the top of the light removal
tower enters the
reboiler to exchange heat with the materials in the bottom of a heavy removal tower, and enters a condenser to be condensed and cooled, the
liquid phase returns to the light removal tower to be extracted as light component impurities; crude
hydrogen bromide extracted from the side line of the light removal tower entersthe heavy removal tower, and heavy impurities are extracted from the tower bottom; a 6N electronic grade
hydrogen bromide product is extracted from the top of the heavy removal tower, and heavy components are extracted from the tower bottom. According to the invention, heat generated by the reaction and a double-effect rectification process are fully utilized, no external heat source is needed, and
liquid nitrogen can be saved by more than 45 percent; the
bromine and hydrogen are selected as reaction raw materials, the
reaction product has less impurities and high bromine selectivity, and canbe 100% converted into
hydrogen bromide.