Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Citation - WoS: 17Citation - Scopus: 22Ultrasonic-Assisted Production of Precipitated Calcium Carbonate Particles From Desulfurization Gypsum(Elsevier, 2021-04) Altiner, Mahmut; Top, Soner; Kaymakoglu, BurcinThis study aimed to investigate the effect of ultrasonic application on the production of precipitated calcium carbonate (PCC) particles from desulfurization gypsum via direct mineral carbonation method using conventional and venturi tube reactors in the presence of different alkali sources (NaOH, KOH and NH4OH). The venturi tube was designed to determine the effect of ultrasonication on PCC production. Ultrasonic application was performed three times (before, during, and after PCC production) to evaluate its exact effect on the properties of the PCC particles. Scanning electron microscope (SEM), X-ray diffraction (XRD), Atomic force microscope (AFM), specific surface area (SSA), Fourier transform infrared spectrometry (FTIR), and particle size analyses were performed. Results revealed the strong influence of the reactor types on the nucleation rate of PCC particles. The presence of Na+ or K+ ions in the production resulted in producing PCC particles containing only calcite crystals, while a mixture of vaterite and calcite crystals was observed if NH4+ ions were present. The use of ultrasonic power during PCC production resulted in producing cubic calcite rather than vaterite crystals in the presence of all ions. It was determined that ultrasonic power should be conducted in the venturi tube before PCC production to obtain PCC particles with superior properties (uniform particle size, nanosized crystals, and high SSA value). The resulting PCC particles in this study can be suitably used in paint, paper, and plastic industries according to the ASTM standards.Article Citation - WoS: 32Citation - Scopus: 41Testing of 17-Different Leaching Agents for the Recovery of Zinc From a Carbonate-Type Pb-Zn Ore Flotation Tailing(Pergamon-Elsevier Science Ltd, 2021-07) Hussaini, Shokrullah; Kursunoglu, Sait; Top, Soner; Ichlas, Zela Tanlega; Kaya, MuammerThe recovery of zinc from a flotation tailing using 17-different leaching agents, including inorganic and organic acids, alkaline solutions and chelating agents, was investigated. The effects of the lixiviant type, acid concentration, leaching temperature, leaching time, and solid-to-liquid ratio on the metals dissolution were studied. The use of sulfuric acid resulted in 91% of zinc extraction with a high selectivity against lead. The major impurities of lead, iron, calcium and arsenic precipitated during the leaching process as a segnisite, beudantite, gypsum, and goethite in this lixiviant. It was seen that the addition of oxidants in sulfuric acid solution slightly increased zinc dissolution. The citric acid dissolved 90.1% of zinc along with 9.1% lead. 90% of zinc dissolution was achieved by using malic acid, and high selectivity between zinc and lead dissolutions was also observed. The citric and malic acid leach residues contained a substantial amount of segnitite, beudantite, and quartz as the major phases. In term of zinc and lead dissolution selectivity, the best inorganic agents were determined in the following order: sulfuric acid > hydrochloric acid > perchloric acid > nitric acid. With organic agents, the best zinc and lead selectivity was achieved in the following order: sulfosalicylic acid > citric acid > malic acid > formic acid > tartaric acid > ascorbic acid. The best simultaneous zinc and lead dissolutions were achieved using sodium hydroxide agent. Using 5 M sodium hydroxide at 80 degrees C and 1/10 solid-to-liquid ratio for 180 min. leaching time, 81.4% of zinc and 47.4% of lead were dissolved while leaving a considerable amount of iron in the residue. When the ammonium chloride was used as a lixiviant, the silver and zinc were taken into the leach solution. 61.3% of zinc dissolution was obtained by using 50% ammonia as lixiviant, whereas no iron and lead dissolutions were observed. Using 0.37 M EDTA at 80 degrees C, 1/10 solid-to-liquid ratio for 180 min. leaching time, more than 90% of zinc dissolved along with a substantial amount of iron, arsenic and lead co-dissolutions. 47.4% of zinc dissolution was obtained at 80 degrees C and 1/10 solid-to-liquid ratio for 180 min. leaching time when sodium citrate was used as lixiviant, whereas less than 20% of zinc dissolved using ammonium oxalate at similar leaching condition. 39% zinc was dissolved using 3 M ammonium acetate at 80 degrees C, 1/10 solid-to-liquid ratio for 180 min., while 23.1% of zinc dissolution was achieved when the ammonium acetate was tested under similar experimental conditions. As a result, sulfuric, citric, malic, sulfosalicylic and formic acids were deemed to be the most promising leaching agents for the selective recovery of zinc from the lead-zinc flotation tailing.Article Citation - WoS: 8Citation - Scopus: 8Separation of Mn and Fe From a Manganiferous Iron Ore Using Horse Dung as Reductant: A Zero Waste Approach(Springer, 2022-01-13) Top, Soner; Altiner, Mahmut; Kursunoglu, SaitThe separation of manganese and iron from a manganiferous iron ore using horse dung (biomass) as reductant was investigated in a sulfuric acid solution, and 99.80% Mn and 17.76% Fe were extracted into the solution under these leaching conditions: 1 M sulphuric acid concentration, 120 g/L biomass, 1/10 solid to liquid ratio, 300 rev/min stirring speed, 90 degrees C leaching temperature, and 3 h leaching time. In the first precipitation step, the iron and aluminum were first rejected from the solution at pH 5.04. Thereafter, 98.58% Mn was precipitated at pH 10 in the second step. The precipitate was identified as a pyrochroite mineral. After the leaching, the residue was subjected to a carbothermal reduction process conducted at 700 degrees C for 10 min in the presence of no extra reductant. The residue was converted to magnetite mineral, which can be easily recovered by magnetic separation. Based on the experimental results, a flowsheet has been proposed.Article Citation - WoS: 5Citation - Scopus: 5Selective Leaching of a Mixed Nickel-Cobalt Hydroxide Precipitate in Sulphuric Acid Solution With Potassium Permanganate as Oxidant(Taylor & Francis inc, 2020-10-12) Hussaini, Shokrullah; Ichlas, Zela Tanlega; Top, Soner; Kursunoglu, Sait; Kaya, MuammerSelective leaching of a mixed nickel-cobalt hydroxide precipitate was investigated using potassium permanganate as oxidant in sulfuric acid solution. 94.9% Ni, 50% Co and 0.6% Mn were dissolved under the following conditions: sulfuric acid concentration of 0.75 M, potassium permanganate of 5 g/L, temperature of 30 degrees C, leaching duration of 60 min, solid-to-liquid ratio of 1/10, and stirring speed of 400rpm. The pregnant leach solution was subjected to a solvent extraction process. 98% Co and 99% Mn were extracted at pH 4.84 with 30% (v/v) Cyanex 272, leaving essentially all nickel in the raffinate. Based on the experimental results, a flowsheet is proposed.Article Citation - WoS: 6Citation - Scopus: 8Removal of Heavy Metals from Wastewater Solution Using a Mechanically Activated Novel Zeolitic Material(Pleiades Publishing Ltd, 2020-11) Uckun, Sukru; Sarikaya, Musa; Top, Soner; Timur, Irfan; Şükrü, Uçkun; Musa, Sarıkaya; Soner, Top; İrfan, TimürThe removal of heavy metals from the wastewater solution using a novel zeolitic material was conceived and experimentally probed. The natural zeolite was ground in a planetary ball mill to increase negative surface charge and amorphization of the material as well as a conventional ball mill. The ground materials were used for the removal of heavy metals from the wastewater solution. The maximum removals were found to be 78% for Pb, 67% for Ni and 54% for Cd by using the conventional milled natural zeolitic material at pH 11. However, 93% of Pb, 72% of Ni and 57% of Cd were removed at pH 9 with the novel zeolitic material milled by a planetary ball mill. It was revealed that the novel zeolitic material produced by a planetary ball mill increased the absorption capacity of the heavy metals and reduced the alkali requirement for pH adjustment. The removal order of heavy metals with the novel zeolitic material is determined as follows: Pb> Ni>Cd.Article Citation - WoS: 4Citation - Scopus: 3Recovery of Vanadium and Nickel From a High Caco3 Containing Petroleum Coke Ash by Roasting and Acidic Leaching(Springer, 2023-11-08) Yurtseven, Ozgun; Ibrahim, Ahmedaljaali Ibrahim Idrees; Top, Soner; Kursunoglu, Sait; Altiner, MahmutIn this study, it was aimed to extract vanadium (V) and nickel (Ni) from a petroleum coke ash (PCA) using a roasting process without additives, followed by leaching with sulfuric acid (H2SO4). The experiments were designed based on the Taguchi approach, taking into account the parameters of temperature, acid concentration, time, and solid ratio. Additional leaching tests were conducted on the non-roasted PCA for comparison, to assess the effect of roasting on the extractions of V and Ni. The results showed that no extra reducing agent was needed as the PCA contained high levels of CaCO3, which could be used as a reducing agent during roasting. It was found that roasting was essential for high Ni extractions, but had no strong effects on V extractions. The Ni extraction was found to be between 13.3 and 80.8% for the non-roasted PCA and between 43.6 and 99.3% for the roasted PCA. The V extraction was between 36 and 97.9% for the non-roasted PCA and between 45.4 and 99.9% for the roasted PCA. The optimal leaching conditions were determined to be a sulfuric acid of 4.5 M, a solid ratio of 10%, a temperature of 75 degrees C, and a time of 75 min. In addition, it was determined that the leaching conditions had a great effect on the oxidation state of vanadium ions, and an increase in the acid concentration led to the formation of V3+ ions (green color) instead of VO2+ ions (blue color) in the pregnant leach solution. The final pregnant leach solution containing 1056.50 mg/L V, and 251.85 mg/L Ni was achieved with an extraction yields of > 98%. The experimental results were greatly fitted by the shrinking core model and the activation energy (E-a) for V and Ni was calculated as 3.60 and 4.01 kJ/mol, indicating that the leaching mechanism can be explained by the diffusion control model.Article Citation - WoS: 7Citation - Scopus: 7Recovery of Lithium From Spent Coin-Type Lithium Manganese Dioxide Cr Cells by Acidic Leaching in the Presence of Potassium Permanganate as Oxidant(Springer, 2022-09-20) Kursunoglu, Sait; Top, Soner; Altiner, Mahmut; Ozsarac, Safak; Kaya, MuammerThe selective leaching of lithium from spent coin-type lithium manganese dioxide CR cells by oxidative leaching and precipitation of Li2CO3 from Li-bearing leach solution has been experimentally and theoretically investigated. The oxidative leaching experiments were carried out using sulfuric acid in the presence of potassium permanganate (KMnO4). The dissolutions of lithium, manganese, nickel, and cobalt were found to be 84.8%, 0.9%, 46.6%, and 9.7%, respectively. The results demonstrated that a considerable amount of manganese and cobalt remained in the leach residue. The Li-bearing leach solution was fed to an impurity removal stage. It was observed that a substantial amount of lithium loss, along with manganese, nickel, and cobalt, was determined at pH 10. At standard temperature and pressure, the species of lithium as a function of pH, lithium concentration, and carbonate concentration was evaluated for the generation of Li2CO3 from the oxidative leach solution. The results revealed that the precipitation of lithium as lithium carbonate is thermodynamically feasible from the solution at high pHs.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: 8Citation - Scopus: 12Recovery of Lead and Zinc From a Citric Leach Solution of a Non-Sulfide Type Ore Flotation Tailing via Precipitation Followed by Solvent Extraction(Springer, 2023-01-12) Hussaini, Shokrullah; Tita, Angela Manka; Kursunoglu, Sait; Top, Soner; Kaya, MuammerThe recovery of zinc (Zn) and lead (Pb) from a citric leach solution of a non sulfide type ore flotation tailing was examined utilizing sulfuric acid precipitation followed by solvent extraction using di(2-ethylhexyl) phosphoric acid (D2EHPA) as the extractant. Following lead precipitation (98.9%) with sulfuric acid, the pregnant leach solution was sent to solvent extraction stage with D2EHPA for the separation of zinc from the other impurities such as Ca, Mg and Fe. The best solvent extraction conditions were determined to be a concentration of 20% D2EHPA, temperature of 25 degrees C, contact time of 10 min and phase ratio of unity. Under the optimum conditions, 98.3% Zn was extracted into the organic phase in a single contact at a pH of 3.6, along with a significant amount of Ca (79%) and minor amounts of Mg (14.7%) and Fe (8.6%). At pH 4.5, the loaded organic solution was carried to the scrubbing stage, where 20 g/L zinc solution was used to remove approximately 91% Ca and 34% Mg from the organic solution. At a pH of 0.25, the loaded organic solution was almost completely stripped of zinc and 27% of calcium in two steps.Article Citation - WoS: 84Citation - Scopus: 93Properties of Fly Ash-Based Lightweight Geopolymer Concrete Prepared Using Pumice and Expanded Perlite as Aggregates(Elsevier, 2020-02) Top, Soner; Vapur, Huseyin; Altiner, Mahmut; Kaya, Dogan; Ekicibil, AhmetThe present paper aims to utilize the fly ash wastes with lightweight aggregates for geopolymer concrete production process in which sodium hydroxide (NaOH) and sodium metasilicate (Na2SiO3) were used as alkali activators, respectively. The designed experiments were examined by the Yates Analyses and so the productions of geopolymer concrete were investigated depending on curing temperature, solid/liquid rate and concentration of alkali activators. The curing temperature and alkali activator concentration were revealed as effective parameters in geopolymerization. The effects of expanded perlite (EP) and acidic pumice (AP) aggregates were discovered for the production of lightweight geopolymer concretes. The microstructural properties of each produced geopolymer concrete were characterized using SEM, EDS and laser particle size analyses. The specifications of the concrete were evaluated based on their uniaxial compressive strength (UCS), point load strength (PLS), sonic speed (SS), Mohs hardness (MH), and water absorption (WAR) ratio results. In addition, the effects of pre-wetting of EP aggregates, which have hydrophilic nature, were examined. To the best of our knowledge, this is the first time that pre-wetted lightweight EP aggregates were used to produce lightweight GP concretes. As a result of pre-wetting, chemical usage decreased by 32.5%. The UCSs of the lightweight geopolymer concretes were in a range of 10-50MPa and their unit weights changed between 1250 and 1700 kg/m(3). Lighter concretes were obtained by the addition of EP aggregates rather than AP ones. (C) 2019 Elsevier B.V. All rights reserved.
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