Polymer coated alumina
AssigneeAluminum Company of America
InventorGwoChung Lin
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Abstract
The invention includes producing a stable polybutadiene film on an alumina support wherein the alumina contains an alumina having a habit or form of crystals formed during a precipitation of aluminum hydroxide from an alkali metal aluminate by preselecting and controlling the pH of the alkali metal aluminate and the addition of certain monohydric and polyhydric alcohols to the alkali metal aluminate solution. Precipitation is controlled to form crystals having a habit or form which varies from principally acicular to principally lamellar crystal forms. This alumina is (a) coated with polybutadiene to form a polymer film layer on the alumina support and (b) the polymer film layer is cross-linked to form a stable polybutadiene coated and crosslinked on a support of acicular or lamellar alumina.
Claims20
A process for producing polybutadiene coated alumina particles wherein the alumina contains an alumina having a habit or form of crystals formed during a precipitation of aluminum hydroxide from an alkali metal aluminate by preselecting and controlling the pH of the alkali metal aluminate and the addition of certain monohydric and polyhydric alcohols to the alkali metal aluminate solution comprising:
- (a) coating an alumina having a habit or form of crystals formed during a precipitation of aluminum hydroxide from an alkali metal aluminate by preselecting and controlling the pH of the alkali metal aluminate and the addition of certain monohydric and polyhydric alcohols to the alkali metal aluminate solution with a solution of polybutadiene, radical generator, and solvent to form a polymer film layer on an acicular or lamellar alumina-based support, and
- (b) crosslinking said film layer to form a stable polybutadiene coating on said alumina-based support.
A process for producing polybutadiene coated alumina useful over a wide pH range at lower pressure drop requirements in a packed separations column comprising:
- (a) coating an alumina having a habit or form of crystals formed during a precipitation of aluminum hydroxide from an alkali metal aluminate by preselecting and controlling the pH of the alkali metal aluminate and the addition of certain monohydric and polyhydric alcohols to the alkali metal aluminate solution with a polybutadiene in pentane solution to form a polymer film layer on said alumina as support base, and
- (b) immobilizing said polymer film layer by crosslinking with a chemical radical generator to form a stable polybutadiene coating on said alumina.
A process for producing a stable polybutadiene coated on a support base of an alumina having a habit or form of crystals formed during a precipitation of aluminum hydroxide from an alkali metal aluminate by preselecting and controlling the pH of the alkali metal aluminate and the addition of certain monohydric and polyhydric alcohols to the alkali metal aluminate solution comprising:
- (a) coating said alumina with a polybutadiene by suspending said alumina in a reactor of solution containing polybutadiene, dicumylperoxide, and solvent, sonicating the solution for about 30 minutes, and evaporating solvent slowly in a rotary evaporator connected to an aspirator to accelerate the evaporation process, said evaporation taking place at a temperature below about 25.degree. C.,
- (b) drying the polybutadiene coated particles with dry nitrogen at a temperature below about 25.degree. C.,
- (c) crosslinking and immobilizing the polybutadiene coated alumina in a temperature programmable oven starting at about 25.degree. C. and heating to about 170.degree. C. at a rate of about 5.degree. C. per minute to form a stable polybutadiene coated and crosslinked alumina product, and
- (d) washing the polybutadiene coated and crosslinked alumina product with a heptane and methylene chloride to remove unreacted polybutadiene.
Dependencies are inferred from the claim text.