Purification method of tungsten hexafluoride gas

• Main Authors: FENG ZHENLEI, CHEN CAIHUA, CHEN ZHIGANG, FANG LANLAN
• Format: Patent
• Language: English
• Published: 14.10.2015
• Subjects: CHEMISTRY; COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F; INORGANIC CHEMISTRY; METALLURGY

A purification method of a tungsten hexafluoride gas relates to a fluoride of tungsten. The purification method comprises the following steps: removing oil by equipment, pressurizing with nitrogen, vacuumizing to the limit, turning on a nitrogen heater, introducing the heated nitrogen into a system, and vacuumizing to the limit; filling a hydrogen fluoride removal tower with nitrogen, putting tungsten hexachloride into the hydrogen fluoride removal tower, introducing high-purity tungsten hexafluoride into a finished product gathering tank, reacting with steam adhered to the wall of the tank to generate hydrogen fluoride, sucking-back impure tungsten hexafluoride in the finished product gathering tank into a rectifying still for low-temperature curing after displacement, detecting content of foreign gas, and stopping high-purity tungsten hexafluoride displacement after qualified; heating primary tungsten hexafluoride and carrying out low-temperature curing, vacuumizing the rectifying still, adsorbing tail gas by a basic spray tower, thawing by hot water, and detecting when pressure is stable and rectifying; carrying out reflux condensation on evaporated tungsten hexafluoride gas in the rectifying tower, removing impurities, rectifying primary tungsten hexafluoride gas and gathering, detecting, gathering by the finished product gathering tank, taking a liquid sample, and detecting metal impurities in tungsten hexafluoride.