Mineral collector compositions and processes

摘要

Collector compositions of a mixture of a C6 to C22 fatty hydroxamic acid and an oil for use in a method the removal of impurities from mineral ores by the froth flotation method. The collectors are prepared by reacting an ester of a C6 to C22 fatty acid with a hydroxylamine salt and a base in the presence of an oil and water to produce an alkyl hydroxamate salt; acidifying the alkyl hydroxamate salt, forming an organic layer and an aqueous layer, wherein the organic layer contains a C6 to C22 fatty hydroxamic acid substantially free of starting esters and hydrolysis and transesterification products of the ester; and separating the organic layer from the aqueous layer to provide a collector composition of the C6 to C22 fatty hydroxamic acid and the oil.