Process for the flotation of base metal sulfide minerals in acid, neutral or mildly alkaline circuits

摘要

A process for the beneficiation of copper sulfide mineral values from base metal sulfide ores with selective rejection of pyrite and/or pyrrhotite or other gangue minerals at pH values of below about 10.0 by froth flotation is disclosed. The process includes the use of a new and improved collector which at pH values below 10.0 exhibits unexpectedly high collector activity for copper sulfide minerals and selectively rejects pyrite and other gangue sulfides or non-sulfides. The collector for copper mineral values for use in the process comprises at least one hydrocarboxycarbonyl thiourea compound having the formula: <IMAGE> wherein R1 is hydrogen or R2; R2 is C1-C8 alkyl and R3 is C1-C6 alkyl or phenyl. In a preferred embodiment of the present invention, froth flotation is conducted under acid pH conditions by adjusting the pH of the flotation slurry with sulfuric acid. The process provides excellent metallurgical recoveries of copper sulfide mineral values of high grade at a substantial reduction in lime consumption and reagents costs associated with prior art flotation separation methods.