Use of chelating agents as collectors in the flotation of copper sulfides and pyrite

Fourteen reagents that are potentially capable of chelating with a metal io n on the surface of the major copper sulfide minerals and pyrite were evalu ated for their effectiveness in floating these sulfides. The reagents studi ed fall into the classes of mercaptobenzole mutations, thiouronium, thionoc arbamates, thiourea, imidazole mutations, oximes, hydroxyquinoline and xant hogen formate. The best overall copper sulfide collector was an imidazoline (1-Hydoxyethyl - 2-Heptadecenyl), but it also proved to be an excellent collector for pyr ite. Its potency as a pyrite collector can be reduced by structural alterat ion, but at some loss in its collecting power for the copper sulfides. The effectiveness of many of these potential collectors can be changed by minor alterations to the collector molecule and, to a lesser extent, by pH adjus tment. The general order of mineral floatability with these reagents is cha lcopyrite = chalcocite > covellite greater than or equal to bornite >> pyri te. The flotation of malachite is generally similar to that of the copper s ulfides, indicating the special effectiveness of copper in the crystal latt ice for collector attachment.