Anthony L Dent

US Patent:

6355596, Mar 12, 2002

Filed:

Jun 1, 1999

Appl. No.:

09/323731

Inventors:

Yatao Hu - Wayne PA
Anthony L. Dent - King of Prussia PA

Assignee:

PQ Holding, Inc. - Wilmington DE

International Classification:

B01J 2106

US Classification:

502350, 502239, 502242

Abstract:

A method for preparing a titanium on silica catalyst, in the form of formed particles such as macrospheres, achieves a controlled titanium distribution type, namely either uniform, eggshell, or intermediate, by selecting the particular titanium precursor depending on its reactivity with hydroxyl groups and by selecting the molar titanium:hydroxyl ratio. Selecting a titanium precursor with a low reactivity and/or adding sufficient titanium precursor to achieve a high molar titanium:hydroxyl ratio aids in forming a uniform distribution of titanium. On the other hand, selecting a titanium precursor with a high reactivity and/or adding only a little titanium precursor resulting in a low molar titanium:hydroxyl ratio aids in forming an eggshell distribution of titanium. Preferred titanium precursors for aiding in the formation of an eggshell distribution of titanium include n-propyl titanate and n-butyl titanate, and preferred titanium precursors for aiding in the formation of a uniform distribution of titanium include titanocene and titanium acetylacetonate. Such silica on titanium catalysts can be used to make epoxidation catalysts, oxidation catalysts, hydroxylation catalysts, and the preferred distribution type depends on the particular application.

US Patent:

43495338, Sep 14, 1982

Filed:

Dec 18, 1980

Appl. No.:

6/217602

Inventors:

Anthony L. Dent - Bala Cynwyd PA
Elliot P. Hertzenberg - Wilmington DE
Howard S. Sherry - Cherry Hill NJ

Assignee:

PQ Corporation - Valley Forge PA

International Classification:

A61K 716
A61K 718
A61K 728

US Classification:

424 52

Abstract:

Crystalline alumino-silicates (zeolites) are multifunctional in dentifrice compositions thereby reducing the number of components required in such formulations. The pH-adjusted zeolites can keep the pH of the dentifrice in the range where caries formation is impossible. The pH-adjusted synthetic or natural zeolites can be prepared or obtained in a particle size range that provides both abrasive cleansing and polishing or lustering of the teeth. The fine particle size and water absorbing capabilities of the zeolite can also provide thickening. Such multifunctional performance allows considerable simplification in the formulation of dentrifice compositions.

US Patent:

43460712, Aug 24, 1982

Filed:

Sep 11, 1980

Appl. No.:

6/186083

Inventors:

Anthony L. Dent - Bala Cynwyd PA
M. Robert Derolf - Pottstown PA
Elliot P. Hertzenberg - Wilmington DE

Assignee:

PQ Corporation - Valley Forge PA

International Classification:

A61K 716

US Classification:

424 49

Abstract:

Silicas that provide improved abrasive action when incorporated in dentifrice compositions can be prepared by dehydrating a silica hydrogel to a low water content and then reintroducing water to gel. The silica hydrogel is prepared by neutralizing a sodium silicate with an acid. This hydrogel is dried by any convenient method so that the gel contains about 15% water or less. This dried gel is rehydrated to about 30% or more. The rehydrated gel provides improved abrasion values over the prior art xerogels and hydrogels.