Abstract: 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: ##STR1## wherein R.sup.1 is hydrogen or R.sup.2 ; R.sup.2 is C.sub.1 -C.sub.8 alkyl and R.sup.3 is C.sub.1 -C.sub.6 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.

Abstract: Alkylaryl hydrocarbons having at least eleven carbon atoms, when used either alone or in combination with known sulfide collectors, result in enhanced recovery and selectivity when used as collectors for sulfide minerals. These alkylaryl hydrocarbons are generally derived from the alkylation of aromatic compounds with the appropriate olefin in synthetic processes. Isopropyl naphthalene appears foremost among these compound as an effective sulfide collector.

Abstract: The disclosure is of the use of a class of chelating agents having active nitrogen and oxygen chelating atoms and which form insoluble chelates with copper, as reagents for the recovery of for example copper values from copper-bearing materials by froth flotation and like techniques.