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Gas Separation Membrane
Patent Number: JP5049881
Publication date: 1993-03-02
Inventor(s): Tsuda Masayuki, Hoshi Masahiko, Tachibana Yakudo, Takei Nobuhiro, Yanagiuchi Mamoru, Suzuki Toshifumi
Applicant(s): NKK Corp, Tsuda Masayuki
Requested Patent: JP5049881
Application Number: JP19900403151 19901218
Priority Number(s):
IPC Classification: B01D71/64
EC Classification:
Equivalents:

Abstract

PURPOSE: To obtain a gas separation membrane excellent in mechanical strength and heat resistance and withstanding the severe conditions at high temp. and pressure by forming the membrane from a polyimide polymer having a repeating unit.

CONSTITUTION: This membrane constituts of a polyimide polymer having a repeating unit shown by the formula (X is >= 2C organic groups). Consequently, a gas separation membrane excellent in mechanical strength and heat resistance and withstanding the severe conditions at high temp. and pressure is obtained. This member is used for obtaining oxygen or nitrogen-enriched air, recovering helium from spent helium mixed with welding gases, refining, and concentrating helium in natural gas, recovering hydrogen from ammonia purge gas, controlling the CO-to-H molar ratio in synthesis gas, recovering hydrogen from the purge gas of the hydrogenating and desulfurizing plant, separating and recovering CO₂ injected when crude oil is recovered from hydrocarbons, separating and recovering CO₂ in natural gas, and separating and recovering methane from a biogas generated from the anaerobic decomposition.