The invention belongs to the technical field of
semiconductor materials, and discloses a method for preparing electronic-grade
hydrogen bromide from industrial-grade
hydrogen bromide, which comprises the following steps: (1) heating an industrial-grade
hydrogen bromide raw material with the HBr content of 0.95-0.999 to 18-20.3 DEG C and the pressure of 20-25 kg, and feeding the industrial-grade
hydrogen bromide raw material into a dehydrating
tower kettle at the flow rate of 10 kg / h; (2) the temperature of the
tower kettle of the dehydrating
tower is 70-80 DEG C, the pressure in the tower is 20-25 kg, the industrial-grade
hydrogen bromide generates rising steam under the action of a tower kettle
reboiler, the rising steam is condensed into a
liquid phase at the tower top, one part of the
liquid phase flows back to the dehydrating tower, and the other part of the
liquid phase is extracted from the tower top of the dehydrating tower as a dehydrated product;
hydrogen bromide containing concentrated water and heavy components is extracted from the tower kettle; (3) enabling a dehydrated product extracted from the top of the dehydrating tower to enter a middle section of a light component removal tower, discharging non-condensable gas from the top of the light component removal tower, and discharging hydrogen bromide from a tower kettle of the light component removal tower at an average flow rate of 8.5-9.5 kg / h / h; the tower top temperature of the light component removal tower is 15-20 DEG C, and the tower kettle temperature is 19-25 DEG C; (4) hydrogen bromide discharged from the tower kettle of the light component removal tower automatically enters a refining tower through
pressure difference, and the temperature of the tower top of the refining tower is 18-22 DEG C; the electronic-grade hydrogen bromide is extracted from the top of the refining tower at the rate of 8kg / h.