Copper extraction from chalcopyrite: Comparison of three non-sulfate oxidants, hypochlorous acid, sodium chlorate and potassium nitrate, with ferric sulfate

Accelerating Copper Leaching from Sulfide Ores in Acid-Nitrate-Chloride Media Using Agglomeration and Curing as Pretreatment

“…This concurs with what was reported by Sokić et al [27], who confirmed that a system with sulfuric acid without the addition of oxidants does not react with chalcopyrite. A mixture with high concentrations of sodium chloride and sodium nitrate in an acid medium was more effective, which concurs with Shiers et al [33], who reported a 92% extraction for the NO 3 − /FeCl 3 (50 • C, 168 h) oxidant. The authors suggested that nitrate is the most cost-effective oxidant.…”

“…Gok and Anderson [30] investigated the effect of addition of sodium nitrite in an acid medium during leaching of chalcopyrite and found that the extraction increased by 5% by using nitrite instead of nitrate, while other conditions remained the same. Shiers et al [33] studied leaching chalcopyrite using different oxidants: hypochlorous acid, sodium chlorate and sodium nitrate with the addition of ferric ions (ferric sulfate, ferric nitrate and ferric chloride), and obtained a copper extraction of 92% in chloride-nitrate-ferric mixture, which proved favorable for chalcopyrite leaching at 50 • C. Tsogtkhankhai et al [34] studied the kinetics of leaching copper with nitric acid, and with the estimation of the activation energy determined that temperature has a strong influence on the system. Castellón et al [35] leached chalcopyrite concentrate in acid-nitrate media using seawater as a dissolvent and obtained a copper extraction of 97% in 24 h under the studied conditions ([H 2 SO 4 ] = [NaNO 3 ] = 0.5 M) at 45 • C. The nitrogen species catalyzed (NSC) method uses sulfuric and nitric acids to leach sulfide minerals with the use of high pressure and temperature.…”

Leaching of Chalcopyrite in Acidified Nitrate Using Seawater-Based Media

“…Copper extraction reached 60% in seawater systems and 48% in water systems (0.5 M H 2 SO 4 ) in 5 days. Thus, the type of nitrate (NaNO 3 or KNO 3 ) does not affect copper extraction, which is consistent with Shiers et al [38]. Figure 3 shows the effect of the type of nitrate.…”

“…Shiers et al [38] carried out leaching tests using nitrate as an oxidant in chalcopyrite concentrate and ore at 50 • C. The authors determined the effect of nitrate, ferric nitrate, ferric chloride and ferric sulfate on copper extraction. A mixed chloride-nitrate system was favorable for extracting copper from chalcopyrite while the presence of ferric chloride was also beneficial.…”

Disposable self-support paper-based multi-anode microbial fuel cell (PMMFC) integrated with power management system (PMS) as the real time “shock” biosensor for wastewater

“…(6)) (Santoro et al, 2011) to 1.63 V (Eq. (7)) (Shiers et al, 2016), leading to a higher OCP of PMMFC sensors. HClO might react with organic matters due to this high standard-state reduction potential, leading to the conversion of PMMFC from MFC to chemical fuel cell.…”