A host material may be used for the separation of elements or compounds, wherein the host material is an organic molecular solid with suitable cavities for accommodating a guest material to be separated, and with interconnections between the cavities to allow the guest material to diffuse through the host material, and wherein said interconnections are closed for a proportion of the time or have a static pore limiting diameter which is smaller than the static dimension of the guest material. Applications include separations of rare gases, chiral molecules, and alkanes. One class of suitable host materials may be made by imine condensation.

A nitrous oxide room temperature purification method, apparatus and system utilizing at least partially oxidized nickel. In an embodiment, a room temperature regenerable N.sub.2O purifier includes a vessel having an inlet and outlet, an active portion being at least partially filled with a purification material comprising nickel oxide and optional elemental nickel, wherein the weight ratio between the nickel oxide and the optional elemental nickel is equal or higher than 3 and the surface area of the nickel oxide and the optional elemental nickel is equal or higher than 50 m.sup.2/g.

An oxygen adsorbent which can be manufactured at a low cost, and an oxygen manufacturing equipment and an oxygen manufacturing method which are capable of producing oxygen-enriched gas at a low cost by using the oxygen adsorbent are provided. The oxygen adsorbent comprises at least an oxide of a perovskite structure. The oxide is represented by a compositional formula of Sr.sub.1xCa.sub.xFeO.sub.3, wherein 0.12x0.40, 00.5 Since this oxide does not include La and Co included in a conventional oxygen adsorbent, it can be manufactured at a low cost.

A nitrous oxide room temperature purification method, apparatus and system utilizing at least partially oxidized nickel. In an embodiment, a room temperature regenerable N.sub.2O purifier includes a vessel having an inlet and outlet, an active portion being at least partially filled with a purification material comprising nickel oxide and optional elemental nickel, wherein the weight ratio between the nickel oxide and the optional elemental nickel is equal or higher than 3 and the surface area of the nickel oxide and the optional elemental nickel is equal or higher than 50 m.sup.2/g.

The present invention concerns a process for the separation of a gas mixture containing CO.sub.2 and at least one inert gaseous species, comprising (a) feeding the gas mixture into an adsorption column via a first inlet located at a first side of the column, wherein the adsorption column contains a solid CO.sub.2 sorbent loaded with H.sub.2O molecules and thereby desorbing H.sub.2O molecules and adsorbing CO.sub.2 molecules, to obtain a sorbent loaded with CO.sub.2 and an inert product stream; and then (b) feeding a stripping gas comprising H.sub.2O into the adsorption column via a second inlet located at a second side which is opposite to the first inlet, thereby stripping the sorbent and desorbing CO.sub.2 molecules and adsorbing H.sub.2O molecules, to obtain a sorbent loaded with H.sub.2O and the CO.sub.2 product stream, wherein the adsorption column is re-used in step (a) after being stripped in step (b). The invention also concerns an apparatus for performing the process according to the invention.