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Dawid J. Duvenhage, Evergreen US

Dawid J. Duvenhage, Evergreen, CO US

Patent application numberDescriptionPublished
20090069451PRECIPITATED IRON CATALYST FOR HYDROGENATION OF CARBON MONOXIDE - A method of producing an iron catalyst for catalyzing the hydrogenation of carbon monoxide is disclosed. The method comprises using a reduced amount of acid for iron dissolution compared to certain previous methods. The resulting acidic iron mixture is heated without boiling to obtain a nitrate solution having a Fe03-12-2009
20090075814PROMOTED, ATTRITION RESISTANT, SILICA SUPPORTED PRECIPITATED IRON CATALYST - A catalyst support solution for improving the attrition resistance of a Fischer-Tropsch catalyst, the solution comprising: crystalline silica and at least one chemical promoter selected from alkali metal bases, wherein the support solution has a pH of greater than or equal to about 7. A structurally promoted catalyst comprising: crystalline silica; at least one basic chemical promoter; and iron; wherein the catalyst comprises SiO03-19-2009
20090298678STRENGTHENING IRON FISCHER-TROPSCH CATALYST BY CO-FEEDING IRON NITRATE AND PRECIPITATING AGENT OR SEPARATELY PRECIPITATING FROM FERROUS NITRATE AND FERRIC NITRATE SOLUTIONS - A method of producing a catalyst precursor comprising iron phases by co-feeding a ferrous nitrate solution and a precipitation agent into a ferric nitrate solution to produce a precipitation solution having a desired ferrous:ferric nitrate ratio and from which catalyst precursor precipitates; co-feeding a ferric nitrate solution and a precipitation agent into a ferrous nitrate solution to produce a precipitation solution having a desired ferrous:ferric nitrate ratio and from which catalyst precursor precipitates; or precipitating a ferrous precipitate from a ferrous nitrate solution by contacting the ferrous nitrate solution with a first precipitation agent; precipitating a ferric precipitate from ferric nitrate solution by contacting the ferric nitrate solution with a second precipitation agent and combining the ferrous and ferric precipitates to form the catalyst precursor, wherein the ratio of ferrous:ferric precipitates is a desired ratio.12-03-2009
20090298681STABLE FERROUS-FERRIC NITRATE SOLUTIONS FOR FISCHER-TROPSCH CATALYST PREPARATION - A method of producing stable ferrous nitrate solution by dissolving iron in nitric acid to form a ferrous nitrate solution and maintaining the solution at a first temperature for a first time period, whereby the Fe(II) content of the ferrous nitrate solution changes by less than about 2% over a second time period. A method of producing stable Fe(II)/Fe(III) nitrate solution comprising ferrous nitrate and ferric nitrate and having a desired ratio of ferrous iron to ferric iron, including obtaining a stable ferrous nitrate solution; dissolving iron in nitric acid to form a ferric nitrate solution; maintaining the ferric nitrate solution at a second temperature for a third time period; and combining amounts of stable ferrous nitrate solution and ferric nitrate solution to produce the stable Fe(II)/Fe(III) nitrate solution. A method of preparing an iron catalyst is also described.12-03-2009
20100152036PRECIPITATED IRON CATALYST FOR HYDROGENATION OF CARBON MONOXIDE - A method of producing an iron catalyst for catalyzing the hydrogenation of carbon monoxide is disclosed. The method comprises using a reduced amount of acid for iron dissolution compared to certain previous methods. The resulting acidic iron mixture is heated without boiling to obtain a nitrate solution having a Fe06-17-2010
20100152307PRECIPITATED IRON CATALYST FOR HYDROGENATION OF CARBON MONOXIDE - A method of producing an iron catalyst for catalyzing the hydrogenation of carbon monoxide is disclosed. The method comprises using a reduced amount of acid for iron dissolution compared to certain previous methods. The resulting acidic iron mixture is heated without boiling to obtain a nitrate solution having a Fe06-17-2010
20100311570SLURRY BED FISCHER-TROPSCH CATALYSTS WITH SILICA/ALUMINA STRUCTURAL PROMOTERS - A method of producing a Fischer-Tropsch catalyst by preparing a nitrate solution, wherein preparing comprises forming at least one metal slurry and combining the at least one metal slurry with a nitric acid solution; combining the nitrate solution with a basic solution to form a precipitate; promoting the precipitate to form a promoted mixture, wherein promoting comprises combining the precipitate with (a) silicic acid and one or more selected from the group consisting of non-crystalline silicas, crystalline silicas, and sources of kaolin or (b) at least one selected from non-crystalline silicas and sources of kaolin, in the absence of silicic acid; and spray drying the promoted mixture to produce catalyst having a desired particle size. Catalyst produced by the disclosed method is also described.12-09-2010
20110313061PROTECTED FISCHER-TROPSCH CATALYST AND METHOD OF PROVIDING SAME TO A FISCHER-TROPSCH PROCESS - A method of preparing a spray dried catalyst by combining spray dried catalyst particles with wax so the spray dried catalyst particles are coated with wax, yielding wax coated catalyst particles, and shaping the wax coated catalyst to provide shaped wax coated catalyst. A method of activating Fischer-Tropsch catalyst particles containing oxides by contacting the catalyst particles with a reducing gas in an activation vessel to produce an activated catalyst, wherein contacting is performed in the absence of a liquid medium under activation conditions. A system for activating a Fischer-Tropsch catalyst containing an activation reactor configured to introduce an activation gas to a fixed or fluidized bed of the Fischer-Tropsch catalyst in the absence of a liquid medium and at least one separation device configured to separate a gas stream comprising entrained catalyst fines having an average particle size below a desired cutoff size from the activation reactor.12-22-2011

Patent applications by Dawid J. Duvenhage, Evergreen, CO US