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:
Nov. 01, 1994
Filed:
May. 11, 1993
Stephen M Davis, Baton Rouge, LA (US);
LeRoy R Clavenna, Baton Rouge, LA (US);
Geoffrey R Say, Baton Rouge, LA (US);
Rocco A Fiato, Basking Ridge, NJ (US);
Exxon Research and Engineering Company, Florham Park, NJ (US);
Abstract
High surface purity heat transfer solids are formed, suitably by washing and treating particulate refractory inorganic solids, notably alumina, which contains as impurities up to about 0.5 wt. % silicon and/or up to about 500 wppm boron, with an acid, or dilute acid solution sufficient to reduce the concentration of silicon and boron in the outer peripheral surface layer of the particles, e.g., as measured inwardly toward the center of a particle to a depth of about 50 .ANG. using X-ray photoelectron spectroscopy, to no greater than about 5 atom percent silicon and boron, preferably about 2 atom percent silicon and boron, based on the total number of cations within said outer peripheral surface layer, thereby reducing the tendency of said particles to sinter and agglomerate in the conversion of said hydrocarbon to hydrogen and carbon monoxide in a fluidized bed synthesis gas operation vis-a-vis particles otherwise similar except that the particles are not treated with the acid. The tendency of the particles to sinter and agglomerate is further reduced by the additional removal of sodium, iron, calcium, and titanium impurities from the outer peripheral surface layer of the particles. Preferably the latter named impurities, or impurities other than silicon and boron, are reduced to a concentration below about 20 atom %, more preferably to a concentration below about 15 atom %, in the outer surface layer of the particles.