Selective recycle production of aluminum chloride

Claim 2

IN PROCESS FOR THE PRODUCTION OF ALUMINUM CHLORIDE BY EXOTHERMICALLY REACING SUBSTANTIALLY HYDROGEN-FREE SODIUM CONTAMINATED ALUMINA HAVING LESS THEN 0.5% OF IRON, SILICON AND TITANIUM IMPURITIES THEREIN AND NO MORE THAN 1.0% OF SODIUM IMPURITIES THEREIN CALCULATED AS NA2O AND AN AVERAGE ALPHA ALUMINA CONTENT OF LESS THAN ABOUT 5% AND AN AVERAGE SURFACE AREA OF AT LEAST ABOUT 10 M2/G, WITH CHLORINE GAS IN THE PRESENCE OF A SUBSTANTIALLY HYDROGEN-FREE SOLID CARBONACEOUS REDUCING AGENT TO FORM A HOT GASEOUS EFFLUENT CONTAINING ALUMINUM CHLORIDE VALUES, ENTRAINED PARTICLES INCLUDING ALUMINUM OXYCHLORIDE VALUES, AND CONDENSIBLE VOLATILE CONSTITUENTS INCLUDING SOLIUM SLUMINUM CHLORIDE VALUES, THE STEPS OF COOLING THE HOT GASEOUS EFFLUENT TO A PREDETERMINED LOW VALUE INTERMEDIATE THE CHLORINATION REACTION TEMPERATURE AND THE CONDENSATION TEMPERATURE OF ALUMINUM CHLORIDE UNDER THE AMBIENT CONDITIONS THERE EXTANT TO CONDENSE AT LEAST A PORTION OF THE SODIUM ALUMINUM CHLORIDE VALUES THEREIN, SEPARATING A MIXTURE OF SUCH CONDENSED SODIUM ALUMINUM CHLORIDE VALUES, AND ENTRAINED PARTICLES INCLUDING ALUMINUM OXYCHLORIDE FROM

Claim 3

Process according to claim 1 wherein said mixture is returned to the chlorination zone in a combined amount of about 15-25% by weight of the alumina introduced into said chlorination zone.

Claim 4

Process according to claim 1 wherein said entrained particles include particles of carbon and alumina.

Claim 5

Process according to claim 1 wherein the chlorination reaction is effected at a temperature of between about 450*-800*C in a fluidized bed and said effluent is cooled to a temperature of between about 200*-600*C.

Claim 6

In a process for the production of aluminum chloride by exothermically reacting chlorine gas at a temperature of between about 450*-800*C in a chlorination zone with substantially hydrogen-free sodium contaminated particles of carbon impregnated porous alumina having less than 0.5% of iron, silicon and titanium impurities therein and no more than 1.0% of sodium impurities therein calculated as Na2O, and an average alpha alumina content of less than about 5% and an average surface area of at least about 10 m2/g to form a hot gaseous effluent containing aluminum chloride, carbon oxides, entrained particles of carbon impregnated alumina and aluminum oxychloride values, and condensable volatile constituents including sodium aluminum chloride, the steps of cooling the hot gaseous effluent to a predermined low value intermediate the chlorination reaction temperature and the condensation temperature of aluminum chloride under the ambient conditions there extant to condense at least a portion of the sodium aluminum chloride values therein, separating such condensed values, and said entrained particles including said aluminum oxychloride values from said gaseous effluent, removing predetermined portions of said separated materials from accumulation thereof and selectively returning the balance thereof to the chlorination zone during the continuance of the chlorination reaction proceeding therein in a combined amount of about 10-30% by weight of the alumina introduced into said chlorination zone to maintain catalytic enhancement of the chlorination reaction and to progressively effect the removal of contaminant oxygen values from said hot gaseous effluent.

Claim 7

In a process for the production of aluminum chloride by exothermically reacting chlorine gas at a temperature of between about 450*-800*C in a chlorination zone with substantially hydrogen-free sodium contaminated particles of carbon impregnated porous alumina having less than 0.5% of iron, silicon and titanium impurities therein and no more than 1.0% of sodium impurities therein calculated as Na2O, and an average alpha alumina content of less than about 5% and an average surface area of at least about 10 m2/g to form a hot gaseous effluent containing aluminum chloride, carbon oxides, entrained particles of carbon impregnated alumina and aluminum oxychloride values, and condensable volatile constituents including sodium aluminum chloride, the steps of cooling the hot gaseous effluent to a predermined low value intermediate the chlorination reaction temperature and the condensation temperature of aluminum chloride under the ambient conditions there extant to condense at least a portion of the sodium aluminum chloride values therein, separating such condensed values, and said entrained particles including said aluminum oxychloride values from said gaseous effluent, removing predetermined portions of said separated materials from accumulation thereof and selectively returning the balance thereof to the chlorination zone during the continuance of the chlorination reaction proceeding therein in a combined amount of about 10-30% by weight of the alumina introduced into said chlorination zone to maintain catalytic enhancement of the chlorination reaction and to progressively effect the removal of contaminant oxygen values from said hot gaseous effluent.

Claim 8

Process according to claim 5 including the step of cooling said hot gaseous effluent to a temperature of between about 200*-600*C.

Claim 9

Process according to claim 5 wherein said separated condensed values and entrained values returned to the chlorination zone comprise, in combined amounts, of about 15-25% by weight of alumina introduced into the chlorination zone.