Method of producing active alumina and the resulting product

Claim 1

A METHOD OF PRODUCING ACTIVE ALUMINA GRANULES WITH HIGH ADSORPTION CAPACITY COMPRISING: (A) SELECTIVELY CALCINING GIBBSITE ALUMINA TRIHYDRATE TO OBTAIN A TRANSITION AND AMORPHORUS ALUMNA COMPRISING IN EXCESS OF ABOUT 95% CHI-RHO ALUMINA, UP TO ABOUT 3% PSEUDOBOEHMITE ALUMINA AND NOT MORE THAN ABOUT 2% GIBBSITE ALUMINA AND CAPABLE OF AT LEAST PARTIAL REHYDRATION; (B) AGGLOMERATING THE SELECTIVELY CALCINED ALUMINA BY MIXING WITH WATER TO PRODUCE GRANULES OF DESIRED CONFIGURATION; (C) CURING THE GRANULES BY IMMERSION IN WATER AT A TEMPERATURE IN THE RANGE OF 140*-212*F. FOR A PERIOD OF TIME TO PARTIALLY REHYDRATE THE ALUMINA TO PRODUCE A TRANSITION MATERIAL COMPRISING FROM ABOUT 46 TO ABOUT 76% CHI-RHO ALUMINA, FROM ABOUT 27 TO ABOUT 42% PSEUDOBOEHMITE ALUMINA, FROM ABOUT 2 TO ABOUT 7% BAYERITE ALUMINA, WITH NOT MORE THAN TRACES OF GIBBSITE ALUMINA AND NOT MORE THAN TRACES OF NORDSTRANDITE ALUMINA; (D) ACTIVATING THE ALUMINA GRANULES BY HEATING AT A TEMPERATURE IN THE RANGE OF 350*-850*F. TO OBTAIN A TRANSITION ALUMINA COMPRISING FROM ABOUT 46 TO ABOUT 76% CHI-RHO ALUMINA, FROM ABOUT 9 TO ABOUT 32% PSEUDOBOEHMITE ALUMINA, NOT MORE THAN ABOUT 40% ETA ALUMINA, NOT MORE THAN ABOUT 33% PSEUDOGAMMA ALUMINA AND NOT MORE THAN TRACES OF BIGGSITE ALUMINA.

Claim 2

A METHOD OF PRODUCING ACTIVE ALUMINA GRANULES WITH HIGH ADSORPTION CAPACITY COMPRISING: (A) SELECTIVELY CALCINING GIBBSITE ALUMINA TRIHYDRATE TO OBTAIN A TRANSITION AND AMORPHORUS ALUMNA COMPRISING IN EXCESS OF ABOUT 95% CHI-RHO ALUMINA, UP TO ABOUT 3% PSEUDOBOEHMITE ALUMINA AND NOT MORE THAN ABOUT 2% GIBBSITE ALUMINA AND CAPABLE OF AT LEAST PARTIAL REHYDRATION; (B) AGGLOMERATING THE SELECTIVELY CALCINED ALUMINA BY MIXING WITH WATER TO PRODUCE GRANULES OF DESIRED CONFIGURATION; (C) CURING THE GRANULES BY IMMERSION IN WATER AT A TEMPERATURE IN THE RANGE OF 140*-212*F. FOR A PERIOD OF TIME TO PARTIALLY REHYDRATE THE ALUMINA TO PRODUCE A TRANSITION MATERIAL COMPRISING FROM ABOUT 46 TO ABOUT 76% CHI-RHO ALUMINA, FROM ABOUT 27 TO ABOUT 42% PSEUDOBOEHMITE ALUMINA, FROM ABOUT 2 TO ABOUT 7% BAYERITE ALUMINA, WITH NOT MORE THAN TRACES OF GIBBSITE ALUMINA AND NOT MORE THAN TRACES OF NORDSTRANDITE ALUMINA; (D) ACTIVATING THE ALUMINA GRANULES BY HEATING AT A TEMPERATURE IN THE RANGE OF 350*-850*F. TO OBTAIN A TRANSITION ALUMINA COMPRISING FROM ABOUT 46 TO ABOUT 76% CHI-RHO ALUMINA, FROM ABOUT 9 TO ABOUT 32% PSEUDOBOEHMITE ALUMINA, NOT MORE THAN ABOUT 40% ETA ALUMINA, NOT MORE THAN ABOUT 33% PSEUDOGAMMA ALUMINA AND NOT MORE THAN TRACES OF BIGGSITE ALUMINA.