The invention relates to a gas purifier that removes moisture and oxygen from inert gases and reducing gases, for example, at sub-atmospheric pressures. The purifier can remove part per million levels of moisture in a gas stream to less than 100 parts per trillion by volume, and has a low pressure drop and a sharp breakthrough curve.

The invention relates to a gas purifier that removes moisture and oxygen from inert gases and reducing gases, for example, at sub-atmospheric pressures. The purifier can remove part per million levels of moisture in a gas stream to less than 100 parts per trillion by volume, and has a low pressure drop and a sharp breakthrough curve.

A method for producing a high-purity hydrogen chloride gas comprises performing a purification process that includes the steps 1) to 3) below on a byproduct hydrogen chloride gas: 1) a crude hydrochloric acid generation step of allowing water to absorb the byproduct hydrogen chloride gas; 2) a volatile organic impurity-removed hydrochloric acid generation step of bringing the crude hydrochloric acid obtained in the step 1) into contact with an inert gas at a liquid temperature of 20 to 45 C. to dissipate volatile organic impurities; and 3) a high-purity hydrogen chloride gas generation step of supplying the volatile organic impurity-removed hydrochloric acid obtained in the step 2) to a distillation column and performing distillation under conditions of a column bottom temperature of higher than 60 C. and 108 C. or lower and a column top temperature of 60 C. or lower to distill out a high-purity hydrogen chloride gas.

Provided is a hydrogen separation filter allowing a hydrogen purification at a lower temperature than conventional one, and a method for manufacturing the same. A hydrogen separation filter includes a porous substrate, a lattice expansion layer formed on the porous substrate and containing a first material, and a hydrogen dissociation and transmission layer formed on the lattice expansion layer and containing a second material selected from the group consisting of Pd, V, Ta, Ti, Nb, and alloys thereof. The first material and the second material have a same crystalline structure. A lattice constant a.sub.1, bulk of a first bulk material having a same composition and a same crystalline structure as the first material and a lattice constant a.sub.2, bulk of a second bulk material having a same composition and a same crystalline structure as the second material satisfy a formula (1):
1.03a.sub.2, bulka.sub.1, bulk1.15a.sub.2, bulk(1).

The present invention provides a method including bringing hydrogen chloride gas into gas-liquid contact with crude hydrochloric acid that has a hydrogen chloride concentration of less than the saturation value and that contains low-boiling-point impurities, suitably at least one selected from hydrogen, nitrogen, oxygen, methane, ethylene, and acetylene, wherein the gas-liquid contact of the hydrogen chloride gas is further continued after the hydrogen chloride concentration reaches the saturation value until an excess amount of 0.1% or more of the mass of the saturated hydrochloric acid has been subjected to the contact treatment.

Disclosed is a system developed for obtaining high purity (minimum 99.999%) nitrogen gas in nitrogen gas purification applications and drying obtained nitrogen gas before applying it on areas of use, and to an operating method of the system.

A system and method of ultra-high purity (UHP) oxygen production from an argon and oxygen producing cryogenic air separation unit incorporating a dedicated methane rejection column or column section having a liquid to vapor (L/V) ratio lower than the L/V ratio in the associated argon rectifier is provided.