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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]

A negative carbon-ion source has been designed and tested at the Dongguk University accelerator mass-spectrometer facility in Korea. The beam-extraction conditions in the ion-source test stand were determined experimentally. Negative carbon-ion beam transport using a dipole magnet for separation was also investigated. Negative carbon was extracted using a 2.5 standard cubic centimeters per minute (sccm) CO2 flow at a −30.0 kV high voltage applied to the plasma electrode. The applied arc current, ion-source magnet could adjust various conditions, and dipole magnet could produce fields up to 5000 G. The effects of various operating conditions and geometrical configurations on beam transport were evaluated in this study. [ABSTRACT FROM AUTHOR]

In South Korea, the manufacturing system from chalcopyrite (CuFeS 2) to Cu products is divided into two parts: electrolytic Cu manufacturing and Cu product manufacturing (CPM). Most of the CPM waste is deposited in landfills unlike the waste generated in electrolytic Cu manufacturing that has a good recycling ability. Therefore, in this study, a method to improve the utilization of CPM waste was proposed as a case study for South Korea. Furthermore, the CPM was investigated and classified into five types in terms of the raw materials, major products, additives, main processes, and characteristics of the CPM waste (waste type, particle size, and chemical composition). Next, the CPM waste was environmentally assessed via leaching toxicity tests using the Korean standard official method, ES 06150. In addition, the amount of specific heavy metals (Pb, Cu, Cd, As, Hg, and Cr6+) was determined to confirm the presence of substances labeled as hazardous waste. Based on these results, a pretreatment method with grinding (under 0.1 mm), screening (0.15 mm grid), magnetic separation (1.0 T), and alkali leaching (30–90 °C and 1–5 mol/dm3) was proposed. The final materials can be categorized into groups, such as fine-particle groups with high Zn and Fe contents, leachate groups with high Cu and Zn concentrations, and metal-scrap groups. Moreover, material flow analysis of all CPM waste streams in the designed pretreatment method was conducted in South Korea in 2019. [Display omitted] • In Korea, copper product manufacturing (CPM) is classified into five types. • Ash, sludge, and slag are generated in every type of CPM. • Tests using Korean standards indicated that CPM wastes have harmful substances. • To utilize the CPM wastes from each type, the pretreatment method is proposed. • This method comprises grinding, screening, magnetic separation, and leaching. [ABSTRACT FROM AUTHOR]

• Low grade pyrophyllite contained impurities, such as pyrite, hematite and rutile. • Microwave roasting caused Fe impurities gaining magnetic property. • Magnetized particles were isolated from pyrophyllite ore by magnetic separation. • Association of Ti mineral with Fe mineral enhanced efficiency of impurity removal. • Isolated Ti impurities was additionally separated under high magnetic field intensity. The applications and price of pyrophyllite are highly dependent on its Al 2 O 3 and impurity contents. Titanium as well as iron in pyrophyllite are impurities causing colorization of the final product. We investigated a method for removal of Fe and Ti impurities to improve the grade of pyrophyllite ore using sequential microwave roasting and magnetic separation. Pyrophyllite ore from the Wando mine (South Korea) contains Fe impurities, such as pyrite and hematite, and Ti impurities, such as rutile and Ti-oxides. This research demonstrate that the ore can be purified by the proposed sequential separation technique using microwave treatment and magnetic separation. The purification efficiency for the low-grade pyrophyllite ore was evaluated by conducting batch-scale sequential treatment tests. The microwave treatment magnetized Fe minerals in the ore due to mineral phase changes, and thus the magnetic impurities could be successfully separated by the subsequent magnetic separation. Iron and Ti were removed from the pyrophyllite ore with 86.3% and 68.3% efficiency, respectively, by 30 min of microwave irradiation and 2000 gauss of magnetic separation. The high removal efficiency of Ti impurity was resulted from association of rutile with Fe minerals, although weak. The efficiency of impurity removal was improved by lengthening the microwave irradiation time and increasing the magnetic field intensity. By applying a high magnetic intensity (>5000 gauss), it was possible to remove additional paramagnetic Ti impurities. The sequential separation technique using microwave roasting and magnetic separation may be a promising method for enhancing the grade of low-grade pyrophyllite ore. [ABSTRACT FROM AUTHOR]