Conoco Inc.

Continental Oil Company

Donald E Stowell

Larry L Bendig

John F Scamehorn

R Tom Jackson

Laura A Starks

Cathy S Siemsen

A method for increasing the pore volume of alumina powder produced by spray drying alumina slurries by heating the slurry to a temperature near the boiling point of water and a pressure up to the critical point of water then introducing the slurry to a spray drying chamber through a small orifice, thereby creating a backpressure in excess of slurry vapor pressure and up to the critical point of water.

High pore volume alumina powders

Alumina spheres having high crush strength are produced by hydrogelling low viscosity acidified alumina slurries in a surfactant-containing ammonia solution, said slurries being inserted into the ammonia solution dropwise.

Production of high strength alumina spheres by hydrogelling

Alumina having a low loose bulk density is obtained by hydrolyzing aluminum alkoxides with water in the presence of lithium hydroxide or lithium salts yielding lithium ions. The amount of density reduction is proportional to the amount of lithium ion present.

Production of low loose bulk density alumina

An improved method for increasing alumina pore volumes said alumina being produced by the hydrolysis of aluminum alkoxides, the improvement comprising diluting the aluminum alkoxide, prior to entering the hydrolysis reactor, with an alkanol containing from 2 to 8 carbon atoms and injecting the dilute solution into the reactor at high velocities.

High pore volume alumina from dilute high injection alkoxide feed

High macro-pore content spheres (&gt;1000A) are produced by use of a rotating wheel, wherein dry alumina is dropped onto the wheel under a peptizing spray misted onto the wheel through an atomizing device. Compressive stresses normally encountered in procedures such as pelletizing are avoided, thereby preserving macro-pores. Size of spheres can be adjusted by altering, for example, the angle at which the wheel rotates.

Production of high pore volume alumina spheres

Alumina spheres are formed by peptizing alumina slurries, centrifugates, and filtercakes, aging and dropping the peptized material through a hydrocarbon filled column. The improved method avoids the drying and reslurrying of alumina powders currently used and provides a method whereby harmful ions such as chloride and sulfates can be excluded from the alumina.

Growing community of inventors

Ponca City, OK, United States of America

Donald E Stowell