Patent ID: 7347982
Filing Date: 2008-03-25
Classification: C01P,C09C

Abstract:
1. A method for purification and refinement of carbon black comprising the steps of: providing a feedstock comprising a physical combination of particulate carbon black, metal oxides, and sulfur; removing the metal oxide particles from the feedstock by introducing the feedstock into an aqueous acidic solution, wherein the aqueous acidic solution dissolves the metal oxide particles from the feedstock; and, removing the sulfur particles from the feedstock by introducing the feedstock into a sulfur-dissolving solvent to produce a sulfur-containing slurry, wherein the sulfur-dissolving solvent dissolves the sulfur from the feedstock; separating the feedstock from the sulfur-containing slurry; evaporating all sulfur-dissolving solvent from the sulfur-containing slurry; removing the sulfur remaining after evaporation of the sulfur-dissolving solvent; and reusing the sulfur-dissolving solvent.