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:
Jan. 02, 2001
Filed:
Aug. 18, 1999
Maryellen Lavin, Hightstown, NJ (US);
Alan P. Cohen, Highland Park, IL (US);
Jack E. Hurst, Leverkusen, DE;
UOP LLC, Des Plaines, IL (US);
Abstract
Difluoromethane (R-32) is of current interest as a partial replacement for chlorodifluoromethane (R-22) refrigerant heretofore widely used in vapor compression refrigeration systems. R-32 has, however, proved to be more reactive than is desirable with the zeolite A adsorbent-desiccant compositions used in such systems to prevent corrosion and freeze-up problems. The potassium cation form of a zeolite A molecular sieve—with at least 60 percent of the sodium cations replaced with potassium ions, agglomerated with a clay binder, and pore-reduced to essentially exclude the adsorption of R-32 having essentially no reactivity with difluoromethane, and having a surface ratio of silicon to aluminum of less than about 1.7 mol/mol as determined by X-ray photoelectron spectroscopy—has been found to be an effective desiccant for refrigerants comprising difluoromethane.