Clay halogenation process

Abstract

One of the major obstacles toward the needed and economic production of alumina and other values from kaolinitic clay and other ores by chlorination has been the slow reaction rates and low yields of the metal values. The present information provides methods for improving reaction rates and/or yields in the halogenation of various ores which comprises the addition of sulfur and/or functionally equivalent sulfur containing compounds as an ore conditioning agent and/or reaction promoter. These improvements also permit operation at low temperatures with advantage of savings of energy and of equipment and maintenance costs. The invention is applicable to both displacement halogenation and carbo-halogenation processes. The sulfur and/or functionally equivalent sulfur containing compounds can be added to the reaction mass during pre-halogenation steps or to the halogenation step or to combinations of steps ordinarily with additional benefits. The preferred embodiments are directed toward the carbochlorination of ores with illustrative examples given for clay, bauxite, ilmenite and aluminum phosphate; and for displacement chlorination of ores with illustrative examples given for hematite and ilmenite.