Purification of phthalic anhydride, glycerol and phenol

Claim 1

A METHOD OF PURIFYING PHTHALIC ANHYDRIDE COMPRISING CONTINUOUSLY SUPPLYING CRUDE PHTHALIC ANHYDRIDE CONTAINING MALEIC ANHYDRIDE AND NAPHTHOQUINONE TO A CHAMBER, OTHER THAN THE LAST CHAMBER, OF A PLURALITY OF REACTION CHAMBERS CONNECTED IN SERIES, CONTINUOUSLY PASSING SAID CRUDE PHTHALIC ANHYDRIDE IN LIQUID FORM THROUGH THE SERIES OF CHAMBERS FROM THE FIRST TO THE LAST, MAINTAINING THE TEMPERATURE IN THE REACTION CHAMBERS AT REFLUX AND CARYING OUT THE REACTION UNDER REFLUX DISTILLATION IN ALL THE CHAMBERS OF THE SERIES SIMULTANEOUSLY AND PERMITTING THE CONDENSATE TO RETURN ONLY TO A REACTION CHAMBER OTHER THAN THE LAST CHAMBER, THE TEMPERATURE IN THE REFLUX CONDENSER BEING MAINTAINED SUFFICIENTLY HIGH TO CAUSE THE MALEIC ANHYDRIDE AND NAPHTHOQUINONE TO REACT IN THE VAPOR PHASE AND YIELD HIGH MOLECULAR WEIGHT CONDENSATION PRODUCTS WHICH FLOW BACK INTO THE REACTION LIQUID, CONTINUOUSLY DISCHARGING THE LIQUID PRODUCT FROM THE LAST CHAMBER OF THE SERIES AND THEN SEPARATING THE PHTHALIC ANHYDRIDE FROM THE HIGH MOLECULAR WEIGHT CONDENSATION PRODUCTS AFTER DISCHARGING THE MIXTURE FROM THE LAST CHAMBER.

Claim 2

A METHOD OF PURIFYING PHTHALIC ANHYDRIDE COMPRISING CONTINUOUSLY SUPPLYING CRUDE PHTHALIC ANHYDRIDE CONTAINING MALEIC ANHYDRIDE AND NAPHTHOQUINONE TO A CHAMBER, OTHER THAN THE LAST CHAMBER, OF A PLURALITY OF REACTION CHAMBERS CONNECTED IN SERIES, CONTINUOUSLY PASSING SAID CRUDE PHTHALIC ANHYDRIDE IN LIQUID FORM THROUGH THE SERIES OF CHAMBERS FROM THE FIRST TO THE LAST, MAINTAINING THE TEMPERATURE IN THE REACTION CHAMBERS AT REFLUX AND CARYING OUT THE REACTION UNDER REFLUX DISTILLATION IN ALL THE CHAMBERS OF THE SERIES SIMULTANEOUSLY AND PERMITTING THE CONDENSATE TO RETURN ONLY TO A REACTION CHAMBER OTHER THAN THE LAST CHAMBER, THE TEMPERATURE IN THE REFLUX CONDENSER BEING MAINTAINED SUFFICIENTLY HIGH TO CAUSE THE MALEIC ANHYDRIDE AND NAPHTHOQUINONE TO REACT IN THE VAPOR PHASE AND YIELD HIGH MOLECULAR WEIGHT CONDENSATION PRODUCTS WHICH FLOW BACK INTO THE REACTION LIQUID, CONTINUOUSLY DISCHARGING THE LIQUID PRODUCT FROM THE LAST CHAMBER OF THE SERIES AND THEN SEPARATING THE PHTHALIC ANHYDRIDE FROM THE HIGH MOLECULAR WEIGHT CONDENSATION PRODUCTS AFTER DISCHARGING THE MIXTURE FROM THE LAST CHAMBER.