Method for converting high-density low-porosity alumina into low-density high porosity alumina

Claim 1

A METHOD FOR CONVERTING DISPERSIBLE HIGH DENSITY, LOWPOROSITY ALUMINA, HAVING A LOOSE BULK DENSITY FROM ABOUT 42 TO ABOUT 50 LB/FT3 AND A PORE VOLUME FROM ABOUT 0.40 TO ABOUT 0.55 CC/G, AND CONTAINING UP TO ABOUT 80 WEIGHT PERCENT AL2O3 AND PRODUCED BY THE WATER HYDROLYSIS OF ALUMINUM ALKOXIDES INTO LOW-DENSITY HIGH POROSITY ALUMINA SAID METHOD CONSISTING ESSENTIALLY OF SEQUENTIALLY; A. DISPERSING SAID HIGH-DENSITY, LOW-POROSITY ALUMINA IN A MIXTURE OF WATER AND AN ACID SELECTED FROM THE GROUP CONSISTING OF HYDROCHLORIC ACID, NITRIC ACID, FORMIC ACID, ACETIC ACID, PROPIONIC ACID, MONOCHLOROACETIC ACID AND DICHLOROACETIC ACID TO FORM A DISPERSION CONTAINING UP TO ABOUT 18 WEIGHT PERCENT AL203 AND WHEREIN SAID ACID IS PRESENT IN AN AMOUNT EQUAL TO FORM ABOUT 0.04 TO ABOUT 0.12 MOLE PER MOLE OF AL2O3; B. ADJUSTING THE PH OF SAID DISPERSION TO A VALUE FROM ABOUT 7 TO ABOUT 11 BY THE ADDITION OF AN ALKALINE MATERIAL, SELECTED FROM THE GROUP CONSISTING OF AMMONIA, AMMONIUM BICARBONATE AND AMMONIUM CARBONATE, THEREBY PRECIPITATING ALUMINA; C. ADMIXING AN ORGANIC SOLVENT SELECTED FROM THE GROUP CONSISTING OF ACETONE, METHANOL, ETHANOL, N-PROPANOL, ISOPROPANOL, N-BUTANOL, ISOBUTANOL AND TERTIARY BUTANOL WITH THE PRODUCTS OF THE PRECIPITATION REACTION IN (B) TO FORM A SOLVENT-AQUEOUS ALUMINA MIXTURE WHEREIN SAID SOLVENT IS PRESENT IN AN AMOUNT SUFFICIENT TO PRODUCE ALUMINA HAVING A LOOSE BULK DENSITY FROM ABOUT 20 TO ABOUT 30 LB/FT3, A PORE VOLUME FROM ABOUT 0.70 TO ABOUT 1.30 CC/G, AND A SURFACE AREA FROM ABOUT 200 TO ABOUT 300 M2/G; AND D. DRYING SAID MIXTURE TO PRODUCE LOW-DENSITY HIGH POROSITY ALUMINA HAVING A LOOSE BULK DENSITY FROM ABOUT 20 TO ABOUT 30 LB/FT3, A PORE VOLUME FROM ABOUT 0.70 TO ABOUT 1.30 CC/G, AND A SURFACE AREA FROM ABOUT 200 TO ABOUT 300 M2/G.

Claim 2

A METHOD FOR CONVERTING DISPERSIBLE HIGH DENSITY, LOWPOROSITY ALUMINA, HAVING A LOOSE BULK DENSITY FROM ABOUT 42 TO ABOUT 50 LB/FT3 AND A PORE VOLUME FROM ABOUT 0.40 TO ABOUT 0.55 CC/G, AND CONTAINING UP TO ABOUT 80 WEIGHT PERCENT AL2O3 AND PRODUCED BY THE WATER HYDROLYSIS OF ALUMINUM ALKOXIDES INTO LOW-DENSITY HIGH POROSITY ALUMINA SAID METHOD CONSISTING ESSENTIALLY OF SEQUENTIALLY; A. DISPERSING SAID HIGH-DENSITY, LOW-POROSITY ALUMINA IN A MIXTURE OF WATER AND AN ACID SELECTED FROM THE GROUP CONSISTING OF HYDROCHLORIC ACID, NITRIC ACID, FORMIC ACID, ACETIC ACID, PROPIONIC ACID, MONOCHLOROACETIC ACID AND DICHLOROACETIC ACID TO FORM A DISPERSION CONTAINING UP TO ABOUT 18 WEIGHT PERCENT AL203 AND WHEREIN SAID ACID IS PRESENT IN AN AMOUNT EQUAL TO FORM ABOUT 0.04 TO ABOUT 0.12 MOLE PER MOLE OF AL2O3; B. ADJUSTING THE PH OF SAID DISPERSION TO A VALUE FROM ABOUT 7 TO ABOUT 11 BY THE ADDITION OF AN ALKALINE MATERIAL, SELECTED FROM THE GROUP CONSISTING OF AMMONIA, AMMONIUM BICARBONATE AND AMMONIUM CARBONATE, THEREBY PRECIPITATING ALUMINA; C. ADMIXING AN ORGANIC SOLVENT SELECTED FROM THE GROUP CONSISTING OF ACETONE, METHANOL, ETHANOL, N-PROPANOL, ISOPROPANOL, N-BUTANOL, ISOBUTANOL AND TERTIARY BUTANOL WITH THE PRODUCTS OF THE PRECIPITATION REACTION IN (B) TO FORM A SOLVENT-AQUEOUS ALUMINA MIXTURE WHEREIN SAID SOLVENT IS PRESENT IN AN AMOUNT SUFFICIENT TO PRODUCE ALUMINA HAVING A LOOSE BULK DENSITY FROM ABOUT 20 TO ABOUT 30 LB/FT3, A PORE VOLUME FROM ABOUT 0.70 TO ABOUT 1.30 CC/G, AND A SURFACE AREA FROM ABOUT 200 TO ABOUT 300 M2/G; AND D. DRYING SAID MIXTURE TO PRODUCE LOW-DENSITY HIGH POROSITY ALUMINA HAVING A LOOSE BULK DENSITY FROM ABOUT 20 TO ABOUT 30 LB/FT3, A PORE VOLUME FROM ABOUT 0.70 TO ABOUT 1.30 CC/G, AND A SURFACE AREA FROM ABOUT 200 TO ABOUT 300 M2/G.