Hydrogen bromide gas drying method

Abstract

The invention relates to a hydrogen bromide gas drying method, and belongs to the field of inorganic chemical engineering and hydrogen bromide gas purification. According to the method, hydrogen bromide gas with water content enters a filling material drying tower from the bottom; a liquid-state inorganic bromide phosphorus tribromide is delivered from the top of the filling material drying tower; the phosphorus tribromide liquid and the hydrogen bromide gas are subjected to countercurrent contact in the filling material drying tower; drying is carried out by using a two-stage series filling material drying tower; the gas is processed by using a defogger, such that dried hydrogen bromide gas with a water content lower than 20ppm is obtained, and bromine element content in the hydrogen bromide gas is partially removed. The phosphorus tribromide liquid can be circularly used. When the concentration of the phosphorus tribromide liquid is lower than 80%, the phosphorus tribromide liquid can be purified through vacuum distillation, and can be recovered. Compared with current other methods, such the method provided by the invention, dehydration efficiency is high, and hydrogen bromide gas water content can be lower than 20ppm. The method is suitable to be used in a production process with relatively low hydrogen bromide gas pressure, and is especially suitable to be used in water removing of hydrogen bromide gas synthesized by combustion bromine in hydrogen.

Description

technical field [0001] The invention relates to a method for drying hydrogen bromide gas, belonging to the technical fields of inorganic chemical industry and hydrogen bromide gas purification. Background technique [0002] Hydrogen bromide gas is widely used in medicine, chemical industry, lighting, semiconductor, solar photovoltaic, especially silicon or chip etching. At present, there are many methods for preparing hydrogen bromide gas, such as bromine burning in hydrogen at high temperature, bromine aromatic hydrocarbon substitution method, bromine-red phosphorus wet method, hydrobromic acid-phosphorus pentoxide dehydration method, phosphorus tribromide water solution and so on. No matter which production method is adopted, the produced gas contains a high concentration of moisture, and the removal of moisture becomes the most important link in the purification of hydrogen bromide gas, which restricts the liquefaction and filling of hydrogen bromide gas into steel cylin...

AI Technical Summary

Problems solved by technology

The method of partially liquefying hydrogen bromide at -70°C has a high dehydration depth, requires low-temperature refrigeration, consumes a lot of energy, is difficult to control, and has little significance for industrial production.

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