In general, the flotation performance of these composites was very good, with high silver recoveries achieved using Potassium Amyl Xanthate
(PAX) as the primary mineral collector.
Thus, less powerful but more selective flotation collector such as potassium amyl xanthate (PAX) was used for sphalerite flotation.
potassium ethyl xanthate (PEX), potassium isopropyl xanthate (PIPX), potassium butyl xanthate (PBX) and potassium amyl xanthate (PAX) were tested for the flotation of galena and sphalerite in the preliminary trials.
Z-14, sodium isobutyl xanthate, is an energetic collector useful in scavenger circuits, while Z-6, potassium amyl xanthate
, is the most powerful and least selective collector.
Figure 4 shows, for an Arizona chalcopyrite ore, a fairly typical set of comparable Cu recovery, rougher grade, and pyrite content data produced by MRI S-701, MRI C-211, MRI F-100, and potassium amyl xanthate
. The enhanced pyrite rejection and lower pH required of the F, S, and C collectors are really obvious and are large in magnitude.
A stronger reagent, potassium amyl xanthate
, enters the process flow at the base of the rougher column.
The reagent suite is standard potassium amyl xanthate (200 g/t) collector and methyl isobutyl carbonyl (MIBC) frother (80 g/t).
distributor overflow reports to the bank at a density of 1.23 t/|m.sup.3~ and is treated with a standard reagent suite of potassium amyl xanthate and MIBC.
Thus ethyl xanthate is weaker than amyl xanthate
, yet more selective.
Acid pressure oxidation tests were conducted on a bulk flotation concentrate containing 86% of the gold [concentrate produced with Cyanimide A-208 (sodium diethyl and sodium di-secondary butyl dithio-phosphate), potassium amyl xanthate
, copper sulfate and frother] at 20% solids, 220 [degrees] C, and with 50 lb/in.02 [O.sub.2] for two hours.