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. 27, 1990
Filed:
Nov. 01, 1988
Mukesh K Jain, Jonquiere, CA;
Sadashiv K Nadkarni, Jonquiere, CA;
Alcan International Limited, Montreal, CA;
Abstract
Porous membranes made of sintered refractory metal oxides, e.g., silica aluimina, titania, zirconia, tungsten oxide, etc., and to a process for their formation. The membranes are formed by dispersing a powder of the metal oxide in an organic polymer. The relative amount of metal oxide to polymer is such that, after the polymer has been carbonized in a subsquent step, there is a stoichiometrical excess of the oxide to carbon. The solution is then shaped to form a desired thin membrane, and the polymer is then carbonized by heating it in a non-oxidizing atmosphere. The resulting oxide/carbon product is heated to a temperature at which (a) the carbon reacts with the oxide to form a volatile sub-oxide and carbon monoxide and (b) the remaining (unreacted) oxide particles sinter together. The heating is carried out in a non-oxidizing atmosphere containing either no nitrogen whatsoever, or an amount of nitrogen less than that which results in the formation of a non-porous product. The sintered membranes can be used, for example, as filters and catalyst supports and have good strength and controlled porosity.