A continuous pressure driven adsorption process for separating a multi-component gaseous mixture. In accordance with the method, the multi-component gaseous mixture is passed through a first portion of the adsorbent to adsorb one or more preferentially adsorbed components while a second portion of the adsorbent is regenerated. The multi-component mixture is passed through the first portion of the adsorbent in sections and the second portion of the adsorbent is regenerated in sections. The sections forming the first portion of the adsorbent become successively less saturated and the sections forming the second portion of the adsorbent becomes successively more concentrated in the more preferentially adsorbed component. A product stream is expelled from the less saturated section of the first portion of the adsorbent. The product stream is enriched in the less preferentially component(s). Masses of adsorbent are continually being shifted between the first and second portions of the adsorbent so that the mass of adsorbent forming the regenerated section is shifted to the first portion of the adsorbent and used to form the least saturated section. The mass of adsorbent forming the most saturated of the sections is shifted to the second portion of the adsorbent and used to form the non-regenerated section. The masses are shifted at a sufficiently high frequency to maintain the sections forming the first and second portions of the adsorbent in their successively less saturated and successively more concentrated states.

Continuous pressure difference driven adsorption process

In using calcium-exchanged forms of zeolite X as selective adsorbents for nitrogen in PSA air separation process, it has been discovered that, particularly under certain temperature and pressure conditions, the peak performance is not, as is generally believed, obtained when the calcium content is at a maximum, but rather when the degree of calcium exchange is in the range of 60 to 89 equivalent percent and only when the framework Si/Al 2 ratio of the zeolite is within the range of 2.0 to 2.4.

Air separation process

In using calcium-exchanged forms of zeolite X as selective adsorbents for nitrogen in PSA air separation process, it has been discovered that, particularly under certain temperature and pressure conditions, superior performance is not, as is generally believed, obtained when the calcium content is at a maximum, but rather when the degree of calcium exchange is in the range of 60 to 89 equivalent percent and only when the framework Si/Al 2 ratio of the zeolite is within the range of 2.0 to 2.4

Nitrogen-selective zeolitic adsorbent for use in air separation process

A method and apparatus is disclosed in the separation of a gaseous mixture by pressure swing adsorption utilizing two beds of adsorptive material which are operated out of phase in the cycle thereby providing a more-or-less continuous flow of product. Each adsorbent bed contains a heat exchange chamber holding a volatile liquid. The liquid gives up vapor in the bed undergoing adsorption and condenses in the bed undergoing desorption. Heat is thereby transferred between the beds, thus improving the efficiency of each stage by retaining heat which would otherwise be lost.

Separation of gaseous mixtures

Process for separating nitrogen from a gas mixture containing nitrogen and at least one gas which is less polar than nitrogen, and employing a differential gas adsorption technique, called PSA process, using an adsorbent of zeolite type, according to which the PSA process is used at a temperature of at least 40° C. by employing as adsorbent a zeolite whose nitrogen adsorption isotherm at 20° C. exhibits a curvature characterized by a parameter C defined by the formula: C = P 1  q  ( P 2 ) P 2  q  ( P 1 ) where q(P1) denotes the quantity of nitrogen adsorbed at pressure P1 and q(P2) that adsorbed at pressure P2, and the pressures P1 and P2 are defined respectively from the high and low pressures of the PSA cycle in question, C being equal to at least 2.5.

Process for separating nitrogen from less polar compounds

@ A process for separating a mixing gas into oxygen and nitrogen under low temperature and low pressure conditions which comprises introducing a mixed gas comprising chiefly oxygen and nitrogen into at least two adsorption towers, each packed with sodium faujasite typical of which is Na-X, at a temperature not higher than room temperature under conditions of an atmospheric pressure to 3 ata thereby causing the nitrogen in the mixed gas to be selectively adsorbed, collecting highly pure oxygen or an oxygen-enriched gas from the outlet of the adsorption towers, and reducing the pressure of the at least two adsorption towers, in which the nitrogen gas been adsorbed, to a level of from 0.08 to 0.5 ata, to cause the nitrogen gas to be desorbed and the sodiumfaujasite to be regenerated.

Shozo C

Papers

Process for separating a mixed gas into oxygen and nitrogen under low temperature and low pressure conditions