Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Citation - WoS: 16Citation - Scopus: 19Recovery of Zinc and Lead from Yahyali Non-Sulphide Flotation Tailing by Sequential Acidic and Sodium Hydroxide Leaching in the Presence of Potassium Sodium Tartrate(Elsevier, 2020-12) Kursunoglu, Sait; Top, Soner; Kaya, MuammerThe recovery of zinc and lead from Yahyali non-sulphide flotation tailing using sulfuric acid followed by sodium hydroxide leaching in the presence of potassium sodium tartrate was experimentally investigated. In the acidic leaching stage, the effects of pH, solid-to-liquid ratio and temperature on the dissolution of zinc from the tailing were explored. 82.3% Zn dissolution was achieved at a pH of 2, a temperature of 40 degrees C, a solid-to-liquid ratio of 20% and a leaching time of 2 h, whereas the iron and lead dissolutions were determined to be less than 0.5%. The sulfuric acid consumption was found to be 110.6 kg/t (dry tailing). The leaching temperature had no beneficial effect on the dissolution of zinc from the tailing. The acidic leach solution was subjected to an electrowinning test. The cathode product consisted of 99.8% Zn and 0.15% Fe. In the alkaline leaching stage, the Pb dissolution increased slightly in the presence of potassium sodium tartrate. More than 60% of Pb was taken into the leach solution when the leaching temperature increased from 40 to 80 degrees C. The final leach residue was analyzed by XRD and XRF. The XRD results indicated that the major peaks originated from the goethite and quartz while minor peaks stem from smithsonite and cemssite. The XRF analysis demonstrated that the residue contained 70.3% iron oxide. Based on the sequential leaching experiments, the zinc and lead were excellently depleted from the flotation tailing, leaving a considerable amount of iron in the final residue.Article Citation - WoS: 14Citation - Scopus: 13Production of Mixed Rare Earth Oxide Powder From a Thorium Containing Complex Bastnasite Ore(Elsevier, 2021-02) Kursunoglu, Sait; Hussaini, Shokrullah; Top, Soner; Ichlas, Zela Tanlega; Gokcen, Hasan Serkan; Ozsarac, Safak; Kaya, MuammerThe production of mixed rare earth oxide powder from a thorium containing bastnasite ore by sulfuric acid bake water leaching followed by precipitation with oxalic acid and thermal decomposition of the oxalates was investigated. The sulfuric acid baking was performed at 250 degrees C and the optimum baking time was found to be 3 h. Using deionized water as lixiviant, 92.6% La, 86.8% Ce, 86.9% Pr, 82.3% Nd, 95.4% Th and 31% Y were dissolved from the baked ore at 25 degrees C after 30 min of leaching. The effect of solid-to-liquid ratio on the dissolution of the rare earth elements and thorium shows that when the solid ratio in the water increased from 1:10 to 1:3, the dissolution percentage decreased. The final mixed rare earth oxide powder contained 88.54% REO and 6% ThO20 together with small amounts of other impurities. The SEM mapping results revealed that the produced REO has an irregular crystal shape. Based on the experimental results obtained from the current study, a flowsheet was proposed for the production of mixed rare earth oxide powder from a specific complex bastnasite ore. (C) 2020 Elsevier B.V. All rights reserved.Article Citation - WoS: 14Citation - Scopus: 18Pb-Zn Recovery From a Malic Leach Solution of a Carbonate Type Ore Flotation Tailing by Precipitation and Solvent Extraction(Elsevier, 2021-10) Hussaini, Shokrullah; Tita, Angela Manka; Kursunoglu, Sait; Top, Soner; Ichlas, Zela Tanlega; Kar, Umut; Kaya, MuammerThe recovery of zinc and lead from a malic leach solution of a carbonate type ore flotation tailing by precipitation with sulfuric acid followed by solvent extraction using di(2-ethylhexyl)phosphoric acid (D2EHPA) as extractant was investigated. The separation of lead via precipitation was essentially complete from the malic acid leach solution by adding sulphuric acid to reach a pH of 0.25 at 25 degrees C. The precipitate product was identified by XRD as anglesite (PbSO4). The pregnant leach solution after lead precipitation was then subjected to solvent extraction using D2EHPA. The optimum solvent extraction conditions were determined as 10% D2EHPA concentration, 25 degrees C temperature, 10 min contact time and phase ratio of unity. Under these conditions, 99.3% of zinc was extracted into the organic phase at a pH of 4.2 in a single contact alongside a substantial amount of Ca (76.6%), and minor amounts of Fe (19.2%) and Mg (18%). Complete stripping of zinc and calcium from the loaded organic solution along with 47.8% of Mg was achieved at a pH 0.5 under room temperature. No iron stripping was observed from the loaded organic. The zinc content in the loaded strip solution could be enriched and then sent to the electrowinning (EW) stage. It is noted that the calcium and magnesium impurities in the loaded strip solution had no adverse effect on the zinc EW process. Based on the experimental results, a flowsheet was proposed for the recovery of Pb and Zn from the malic acid leach solution. With the proposed precipitation and solvent extraction process, two different material streams are produced.Article Citation - WoS: 15Citation - Scopus: 20Leaching Method Selection for Caldag Lateritic Nickel Ore by the Analytic Hierarchy Process (AHP)(Elsevier, 2017-08) Kursunoglu, Sait; Ichlas, Zela Tanlega; Kaya, MuammerLeaching is an important process in hydrometallurgical operations. This process is used to extract metals from the ores by dissolving them in a lixiviant. It is desired that the leaching method is able to provide high extraction rate at minimal capital and operational costs. There are many parameters that can affect the leaching efficiency and thus, the process of selecting a leaching method is complex. In this study, the use of Analytic Hierarchy Process (AHP) method to select an appropriate leaching method for Caldag lateritic nickel ore has been performed. The application of AHP is assisted with the use of ExperChoice 2000 (R) Software. The results shown that heap leaching (HL) is the most attractive leaching method with a rating of 0.592, followed by atmospheric leaching (AL), and high pressure acid leaching (HPAL) with ratings of 0.293 and 0.115, respectively. In addition, sensitivity analyses have been applied to investigate the impact of the main criteria on the alternative leaching methods. It was found that HPAL can be selected when economical main criteria decreased from 76.1% to 16.3%.Article Citation - WoS: 143Citation - Scopus: 161Critical Review on Secondary Zinc Resources and Their Recycling Technologies(Elsevier, 2020-08) Kaya, Muammer; Hussaini, Shokrullah; Kursunoglu, SaitIn a race to save the earth of its rapidly depleting natural resources, the use of Secondary Raw Materials (SMRs) as alternative replacements in several processes is currently intensively pursued. The valorization of SMRs is consistent with the sustainable circular economy, where resource efficiency is maximized for the benefit of both the economy and green environment. In line with this mandate, this article focuses on investigating recent studies on secondary zinc (Zn) resources and describing state-of-art Zn recycling technologies. Globally, some of the main Zn-containing secondary raw materials are mine/concentrator/smelter tailings, wastes, slags, scraps, dust, etc. Although the pyrometallurgical process has been dominant in the secondary metal recycling processes, there has been growing interest and pressure to achieve sustainable and greener recycling methods to remediate the environmental problems caused by emissions of toxic heavy metals and sulfur oxides in the traditional smelting process. In the last decades, many sustainable and environmentally friendly novel hydrometallurgical processes for Zn extraction were developed to overcome tougher legislation and meet cost competitiveness. Secondary Zn recycling focuses on the development of selective Zn-rich but Pb, Fe, As-lean recovery processes.