process for separating the para isomer from a feed mixture comprising at least two isomers of monocyclic aromatic bialchilso consisting

摘要

1535232 Zeolite adsorbent UOP Inc 19 Feb 1976 [27 March 1975] 06540/76 Heading C1A [Also in Division C5] A zeolite adsorbent for separating alkylaromatics is prepared by:- contacting a base material comprising Y zeolite with an aqueous sodium hydroxide solution at first ion exchange conditions to effect the addition of sodium cations to said base material; treating the sodium-exchanged base material at second ion exchange conditions to effect essentially complete exchange of the sodium cations with one or more cations selected from potassium, cesium and rubidium; and drying the so-exchanged material to reduce the LOI (loss on ignition) at 900‹ C. to less than 10 weight per cent.