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The mineralogy of beach sand, which was sampled from an island, Jumundo of South Korea, was investigated and beneficiated using gravity and magnetic separation processes. Ilmenite was determined to be a major heavy mineral and, as minor heavy minerals, zircon, monazite, and sphene were observed. Quartz, biotite, microcline, kaolinite, hornblende, and chlorite were present as gangue minerals. The Ilmenite was concentrated with a Humphrey spiral concentrator and shaking table followed by magnetic separators (drum and cross belt types). As a final product, 18% of the Humphrey spiral system concentrate was recovered, and the grade of final product was determined to be 93% ilmenite. The electron probe microscope analysis indicates that ilmenite was a solid solution of major FeTiO3, minor MgTiO3 (geikielite), and MnTiO3 (pyrophanite). [ABSTRACT FROM AUTHOR]

The leaching behaviors of tin (Sn), antimony (Sb), iron (Fe), and lead (Pb) from non-magnetic fraction of Pb dross, which was obtained from magnetic separation process to remove As components, were investigated using HCl solution. The leaching efficiencies of Sn, Fe, and Pb increased with increasing agitation speed, temperature, and HCl concentration and with decreasing pulp density, but Sb was dissolved only in the 3 and 5 M HCl solutions. The leaching efficiencies of metals increased to 100% in the 5 M HCl solution at 400 rpm and 70°C with 1% pulp density within 120 min. In the case of leaching test with 1 M HCl, Sb components could be recovered as leach residue. After leaching test, Pb could be recovered as PbCl2 from the solution by lowering temperature. Tin ions were extracted selectively by solvent extraction with tri-butyl phosphate, remaining Fe and Pb ions in the solution. The process consisting of HCl leaching, precipitation, and solvent extraction recovers successfully Sb, Pb, and Sn from non-magnetic fraction of Pb dross. [ABSTRACT FROM AUTHOR]

• Tailings are considered secondary resources of valuable metals. • Reprocessing sulfide tailings can add value to these wastes and prevent the formation of acid mine drainage (AMD). • This review presented the various separation methods for recovering valuable metals from sulfide mineral tailings. • Various advanced separation techniques tailored to specific tailings characteristics have been applied for metals recovery. Reprocessing sulfide minerals in tailings is an attractive option for sustainable tailings management. It can reduce the environmental impact generated by acid mine drainage while recovering valuable metals from tailings. Conventional mineral processing techniques often face challenges when it comes to reprocessing mine tailings, primarily due to factors such as particle size and surface oxidation. By addressing these challenges with targeted strategies, it's possible to improve recovery efficiencies and make the reprocessing of mine tailings more economically viable and environmentally sustainable. Various advanced techniques are able to target specific tailing properties and achieve high recovery efficiency. This review paper covers various conventional mineral processing methods and their technological advances for reprocessing tailings as follows: (1) flotation with novel machines and reagents, (2) advanced gravity separation, (3) centrifugal dense medium separation, and (4) high-gradient magnetic separation. [ABSTRACT FROM AUTHOR]

• Co was separated from leach solution with Mn by cementation process with Zn powder. • After magnetic separation, Co was concentrated in a magnetic fraction. • Unreacted Zn powder was recovered as a non-magnetic fraction. • The unreacted Zn powder could be reused as a cementation reagent. A cementation process with Zn powder followed by magnetic separation was conducted to separate Co as precipitate from leach solution containing Mn ions and to recover unreacted Zn and concentrated Co from cementation precipitate. The separation of Co component from Mn could be achieved successfully by a cementation process performed under the following conditions; 200 mg/L Cu, 140 mg/L Sb, pH 3.3–3.7, temperature 85 °C, and 1% Zn powder, where Cu and Sb were used as cementation activators to avoid the redissolution of Co. Magnetic separation of the cementation-precipitate was performed using 2000 G magnetic rod, and the results showed that Zn distributed more in non-magnetic fraction while Co, Cu, Sb were contained more in magnetic fraction. The Co was concentrated to 8.3% in magnetic fraction of the precipitate obtained from 60 min-cementation test. The non-magnetic fraction contained the unreacted Zn powder, which could be reused for cementation test for precipitating Co. [ABSTRACT FROM AUTHOR]

Printed circuit boards incorporated in most electrical and electronic equipment contain valuable metals such as Cu, Ni, Au, Ag, Pd, Fe, Sn, and Pb. In order to employ a hydrometallurgical route for the recycling of valuable metals from printed circuit boards, a mechanical pre-treatment step is needed. In this study, the metallic components from waste printed circuit boards have been enriched using a mechanical separation process. Waste printed circuit boards shredded to <10mm were milled using a stamp mill to liberate the various metallic components, and then the milled printed circuit boards were classified into fractions of <0.6, 0.6–1.2, 1.2–2.5, 2.5–5.0, and >5.0mm. The fractions of milled printed circuit boards of size <5.0mm were separated into a light fraction of mostly non-metallic components and a heavy fraction of the metallic components by gravity separation using a zig-zag classifier. The >5.0mm fraction and the heavy fraction were subjected to two-step magnetic separation. Through the first magnetic separation at 700Gauss, 83% of the nickel and iron, based on the whole printed circuit boards, was recovered in the magnetic fraction, and 92% of the copper was recovered in the non-magnetic fraction. The cumulative recovery of nickel–iron concentrate was increased by a second magnetic separation at 3000Gauss, but the grade of the concentrate decreased remarkably from 76% to 56%. The cumulative recovery of copper concentrate decreased, but the grade increased slightly from 71.6% to 75.4%. This study has demonstrated the feasibility of the mechanical separation process consisting of milling/size classification/gravity separation/two-step magnetic separation for enriching metallic components such as Cu, Ni, Al, and Fe from waste printed circuit boards. [Copyright &y& Elsevier]