The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 01, 1976
Filed:
Jan. 24, 1975
Donald H Rosback, Elmhurst, IL (US);
Universal Oil Products Company, Des Plaines, IL (US);
Abstract
A solid adsorbent useful for the separation of para-xylene from a mixture of C.sub.8 aromatic hydrocarbons. The adsorbent is prepared by the steps of: ion-exchanging a precursor mass containing type X or type Y zeolite and amorphous material with an aqueous sodium hydroxide solution to effect the addition of sodium cations to the zeolite structure, ionexchanging the sodium-exchanged mass to effect the essentially complete exchange of sodium cations, and drying the resulting material at conditions to reduce the LOI at 900.degree. C. to less than about 10 wt. %. The sodium cations can be essentially completely exchanged with barium and potassium cations in a weight ratio of from about 1.5 to 200 or with barium alone. I have found that the sodium hydroxide exchange step produces an adsorbent that has faster adsorption-desorption rates for the desired para-xylene isomer and permits a suitable adsorbent to be produced which contains barium cations alone.