US 12,264,081 B2
Tungsten hexafluoride manufacturing method, tungsten hexafluoride purification method, and tungsten hexafluoride
Takashi Suenaga, Ube (JP); Takuya Kita, Ube (JP); and Ryuichi Nakamura, Ube (JP)
Assigned to CENTRAL GLASS COMPANY, LIMITED, Yamaguchi (JP)
Appl. No. 17/442,445
Filed by CENTRAL GLASS COMPANY, LIMITED, Yamaguchi (JP)
PCT Filed Mar. 19, 2020, PCT No. PCT/JP2020/012268
§ 371(c)(1), (2) Date Sep. 23, 2021,
PCT Pub. No. WO2020/196248, PCT Pub. Date Oct. 1, 2020.
Claims priority of application No. 2019-056045 (JP), filed on Mar. 25, 2019.
Prior Publication US 2022/0348477 A1, Nov. 3, 2022
Int. Cl. C01G 41/04 (2006.01)
CPC C01G 41/04 (2013.01) 12 Claims
OG exemplary drawing
 
1. A tungsten hexafluoride manufacturing method, comprising:
a reaction step of reacting tungsten with a gas of a fluorine element-containing compound so as to obtain a mixture that contains tungsten hexafluoride and hydrogen fluoride-containing impurities; and
a discharge step of performing distillation of the mixture while performing a discharge operation at least two or more times during the distillation so as to obtain tungsten hexafluoride, the discharge operation being an operation in which the following storage operation and purge operation are alternately performed,
(operation)
storage operation: an operation of creating a total reflux state in a distillation column and then obtaining a mixture gas containing the concentrated hydrogen fluoride in a gas phase portion in the distillation column, and
purge operation: an operation of purging the mixture gas from an upper portion of a condenser provided in the gas phase portion and then stopping the purging.