Dissolution of copper from smelting slag by leaching in chloride media

Abstract

Leaching of copper smelting slag in chloride media was studied. The lixiviants used were aqueous solutions of hydrochloric acid (0.5-2.0 M HCl) as well as hydrogen peroxide and hydrochloric acid (0.5-3.0 M H 2 O 2 , 1.0 M HCl). The maximum final copper extraction from the slag of 73% was attained with 3 M H 2 O 2 , at room temperature after 120 minutes of reaction. At the same time, 55% of the iron from the slag was also dissolved. The copper extraction increased during the first 60 minutes of reaction and essentially ceased thereafter. Because of a rapid catalytic decomposition of hydrogen peroxide, it should be added contiuously to the leach suspension rather than at once at the begining of the experiment. In fact, it appears that almost complete dissolution of copper from the slag is achievable after about 4 hours of leaching by implementing the method of continuous lixiviant addition. Also, it seems that the final iron extraction could be limitied to as low as 20% by using this method.

Development of an analytical model for copper heap leaching from secondary sulfides in chloride media in an industrial environment

“…This resource has begun to be exploited in recent decades in Chilean mining [28], mainly due to the situation of water scarcity in the country. It is worth highlighting the rise in copper leaching in chloride media, finding applications, as stated in the literature, from processing of secondary copper sulfide minerals [22,23,29,30], to copper smelting slag leaching [31,32]. On the other hand, though leaching of primary copper sulfides, such as chalcopyrite [33,34], is also possible, it is economically infeasible at industrial scale.…”

Pressure Leaching of Copper Slag Flotation Tailings in Oxygenated Sulfuric Acid Media

“…Several researchers have investigated the extraction of metals from slags using various extractants, such as ferric chloride, , ferric sulfate, , ammonium chloride, chlorine solution, , sulfuric acid, ,− hydrochloric acid, , ammonium hydroxide, nitric acid, , and aqua regia, − as leaching agents. Sulfating or chloride roasting can be applied to convert sulfide phases to soluble sulfate compounds prior to water or dilute acid leaching.…”

Metal mobility and toxicity of reclaimed copper smelting fly ash and smelting slag

“…Researchers have performed a signicant amount of research into the treatment and resource utilization of RCS y ash and smelting slag to make it harmless. 4,11,12 This research mainly includes water leaching, 13 acid leaching, [14][15][16][17] oxidation leaching, 18,19 bioleaching, 20,21 pressure oxidative leaching, 14 chloride leaching, 22 alkali leaching, 1 controlling potential leaching, 23 the leaching-extraction method and the leachingblast furnace smelting method. 24 The copper and zinc in RCS y ash and smelting slag can be leached using water or dilute sulfuric acid, and the leaching solution and leach residue can be treated using other methods.…”