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. 15, 1994
Filed:
Sep. 22, 1992
Sridhar Komarneni, State College, PA (US);
Prakash B Malla, State College, PA (US);
Gas Research Institute, Chicago, IL (US);
Abstract
The present invention relates to a controlled process for producing amorphous, microporous silica gels having a predetermined water sorption isotherm of moderate Type I shape having a separation factor between about 0.07 and 0.1 and micropore diameter size between about 6 and 8.7 angstroms. The present microporous silica gels are prepared by adjusting the pH of the reaction system or by doping the system with various elements during the hydrolysis and condensation of alkoxy silicates to form silica gels therefrom, and the hydrolyzed products are successively polymerized to form polymers and particles containing siloxane bonds as follows: ##STR1## Various factors, for example open vs closed system, amount of water used for hydrolysis, type of alkoxides and solvent, pH, amount of catalyst, temperature, aging and drying conditions etc., affect the nature and the rate of hydrolysis, condensation reactions and network formation, and consequently the properties of the final gel products.