Process for manufacturing particles of X zeolite exchanged with metal cations

Abstract

A process for manufacturing particles of type X zeolite exchanged with at least lithium cations and having an Si/Al ratio less than or equal to 1.5, in which (a) at least one mother liquor containing lithium salts having a molar purity in excess of 95% is percolated through a bed of zeolite particles, the mother liquor making it possible to obtain a limit exchange factor (LEF) for the zeolite particles of between 90 and 100%, (b) the percolation of the mother liquor is stopped when an amount of mother liquor has been used which makes it possible to obtain a mean real exchange factor (REF) such that: REF=LEF−2%±1%; and (c) the lithium-exchanged zeolite particles are recovered. The particles of faujasite, preferably X, zeolite exchanged to at least 88% with lithium cations and having an Si/Al ratio less than or equal to 1.5 which are obtained by such a manufacturing process can be used as adsorbent in a PSA, preferably VSA, process for separating or purifying a gas flow.

Dependencies are inferred from the claim text.