Abstract: An improved method of and an apparatus for measuring a very low water content in a non-condensible gas which has a dew point in the range of from ordinary temperature to -80.degree. C. or less. The gas to be measured is pre-cooled to a temperature slightly higher than that of the dew point, and is then blown against a reflecting mirror whose surface is cooled down to the dew point temperature of the gas. A condensed light having high luminance is projected toward the reflecting mirror. When the gas is blown against the mirror and cooled down to the temperature of the dew point, thereof a dew or frost is formed on the mirror, and the amount of scattered light reflected from the mirror is increased by the dew or frost. This increase in scattered light is detected by a photodetector. A silicon wafer which is polished to have a surface precision of 1/4 or less that of the wavelength of the condensed light is employed as the mirror to enable measurement of dew points of -80.degree. C. or less.

Abstract: A process for separating enriched oxygen and argon from air through pressure swing adorption by using an adsorbent which is capable of selectively adsorbing nitrogen. Product gas is recovered from one adsorption column in which the adsorption step has already been completed by moving the gas to another adsorption column in which regeneration of the adsorbent by pressurization with the product gas has already been completed on the basis of pressure equalization. In this case, at the same time as the gas is being moved from the feed end of one column to the feed end of another, the gas may also be moved from the effluent end of the former to the effluent end of the latter. In this way, it is possible to stably and readily obtain an enriched oxygen gas having a lowered nitrogen content at an increased specific product and a lowered specific power consumption.

Abstract: A process for deodorizing an exhaust gas containing at least one smelly material selected from the group consisting of acidic smelly materials, such as hydrogen sulfide, mecaptans, dimethyl sulfide, dimethyl disulfide and the like; basic smelly materials, such as ammonia, amines and the like; and smelly organic material, such as ketones, alcohols, aldehydes, carboxylic acids and the like is disclosed. Vapor-liquid contact of the exhaust gas with a sodium hypochlorite solution is caused in the presence of a catalyst which is a mixture of nickel peroxide and at least one carrier. In the presence of the catalyst, placed in a column, sodium hypochlorite solution falling from the upper portion of the column contacts exhaust gas rising from the lower portion of the column to promote catalyst oxidation reaction.