Zirconium silica hydrogel compositions and methods of preparation
AssigneeMMII Incorporated
InventorsDominick A. DeSantis, Robert A. Paul
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Abstract
Zirconium silica hydrogels are disclosed including at least about 5 wt. % water bound as a hydrate and including silicon as SiO.sub.2 in amounts of from 60 to 99 wt. % and zirconium as ZrO.sub.2 in amounts of from 1 to 40 wt. %, and where substantially all of the zirconium is bound to the SiO.sub.2 in the hydrogel. Hydrophobic zirconium silica hydrogels are also disclosed in which a hydrophobic component, such as organosiloxanes, organosilanes, primary and secondary higher aliphatic alcohols, and long chain amines, are bound to the surface of the hydrogel, and in which the zirconium is present in amounts sufficient to improve the stability of the hydrogels. Methods of manufacturing these zirconium silica hydrogels are also disclosed.
Claims32
A substantially pure zirconium silica hydrogel containing at least about five wt. % water bound as a hydrate in its as-dried form comprising silicon and zirconium including silicon as SiO.sub.2 in an amount of between about 60 and 99 wt. % of said hydrogel and zirconium as ZrO.sub.2 in an amount of between about 1 and 40 wt. % of said hydrogel, wherein substantially all of said zirconium is bound to said SiO.sub.2 in said hydrogel, and said hydrogel is substantially free of silica gel which is not bound to said zirconium, said hydrogel having a surface hydroxyl content greater than about one OH group per nm.sup.2.
A hydrophilic zirconium and silica or silicate-containing hydrogel including surface silanol groups such that such hydrogel has a surface hydroxyl content greater than about one OH group per nm.sup.2 and comprising at least about 5 wt. % water bound as a hydrate in its as-dried form comprising silicon and zirconium wherein substantially all of said zirconium is bound to the surface of said hydrogel.
A method for manufacturing zirconium silica hydrogel comprising reacting an alkali metal silicate with a zirconium compound in an aqueous medium wherein said reaction is primarily a zirconium silica co-precipitation at a pH of between about 10 and 12 so as to produce a zirconium silica hydrogel containing at least about 5 wt. % water bound as a hydrate and including silicon as SiO.sub.2 in an amount of between about 60 and 99 wt. % of said hydrogel and zirconium as ZrO.sub.2 in an amount of between about 1 and 40 wt. % of said hydrogel, wherein substantially all of said zirconium is bound to said silica in said hydrogel, and subsequently adjusting said pH of said hydrogel so as to neutralize same.
A method for manufacturing a zirconium silica hydrogel comprising reacting zircon with an alkali metal compound at elevated temperatures so as to produce a soluble zirconyl silicate, and precipitating said zirconium silica hydrogel from said soluble zirconyl silicate at a pH of between about 10 and 12 so as to produce said zirconium silica hydrogel containing at least about 5% water bound as a hydrate and including silicon as SiO.sub.2 in an amount of between about 60 and 99 wt. % of said hydrogel and zirconium as ZrO.sub.2 in an amount of between about 1 and 40 wt. % of said hydrogel, and subsequently adjusting said pH so as to neutralize said hydrogel.
A method for manufacturing a zirconium silica hydrogel comprising providing a silica-containing compound including surface silanol groups, and contacting said silica-containing compound with a zirconium compound so as to bind said zirconium to the surface of said silica-containing compound, said zirconium being present in an amount sufficient to improve the stability of said silica-containing compound and having a surface hydroxyl content greater than about one OH group per nm.sup.2, and drying said hydrogel at a temperature of between about 100 and 300.degree. C.
Dependencies are inferred from the claim text.