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1

Chemia nieorganiczna : 80 lat historii w UMCS

Kołodyńska Dorota, Hubicki Zbigniew

Wiadomości Chemiczne

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2024

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[Z] 78, 9-10

1079--1104

EN

The article describes the history, origin and development of inorganic chemistry at the Marie Curie-Skłodowska University in Lublin. The profiles of the first heads of the Department of Inorganic Chemistry and the history, research topics and didactic and organisational achievements of the unit are presented.

2

Characterization and concentration of U, Nb, Pb, Ag, and Fe from the Huayangchuan polymetallic ore

Cheng Hongwei, Lv Zihu, Wu Dongyin, Zhao Dengkui

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 2

art. no. 188070

EN

The separation and recovery of valuable metals from the Huayangchuan uranium polymetallic ore was investigated based on mineralogical research and mineral processing experiments. The most promising valuable elements in the ore, according to mineralogical studies, are U, Nb, and Pb. 95.75% of U and 93.00% of Nb are found in betafite, 46.85% of Pb is present in galena, 52.01% of Pb occurs in cerussite, and associated Ag exists primarily in galena. The beneficiation process involving gravity concentration, magnetic separation, and flotation was determined based on the mineralogical characteristics of the ore. The U-Nb concentrate with U grade of 3578 ppm and recovery of 83.18 %, Nb2O5 grade of 4391 ppm and recovery of 74.55 % can be obtained, and five elements including U, Nb, Pb, Ag, and Fe are recovered. Compared with the previous beneficiation experimental process, the flowsheet is greatly simplified and the beneficiation recovery efficiency has been improved. The results of this investigation can help to address the gaps in the processing of low-grade uranium deposits with similar mineralogical properties.

3

A hydrometallurgical process for the recovery of copper metal and nickel hydroxide from the aqua regia leaching solutions of printed circuit boards

Nguyen Thi Nhan Hau, Wen Jiangxian, Lee Man Seung

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 4

art. no. 191551

EN

Leaching solutions of printed circuit boards (PCBs) contain noble and base metal ions. The precious metal ions present in the leaching solutions of PCBs could be separated by cementation with copper metal. After recovery of precious metal ions by cementation, the filtrate contains Cu(II) together with base metal ions like Al(III), Fe(III), Fe(II), Ni(II), Sn(II), and Zn(II). In this work, separation experiments were conducted to recover Cu(II) and Ni(II) from the filtrate. First, copper ions were completely separated from the filtrate by chemical reduction with hydrazine at the following conditions: a molar ratio of 8 for hydrazine to Cu(II), 20°C, 500 rpm, and 20 mins. By adding sodium oxalate to the solution after separation of Cu(II), most of the Ni(II) and 38% of the Zn(II) were co-precipitated at 20°C, 60 mins, 500 rpm, and a molar ratio of 20 for sodium oxalate to nickel. After dissolving the coprecipitates of Ni(II) and Zn(II) oxalates in a 0.5 M HCl solution, the Zn(II) was completely removed from the solution by a five-stage cross-current extraction with 2.5 M Cyanex 272. Nickel hydroxides were then recovered from the raffinate by precipitation with NaOH. The purity of the copper metal and nickel hydroxides was higher than 99%. A process was proposed to recover Au(III), Pd(II), Cu(II), and Ni(II) from the leaching solutions of PCBs.

4

On Iiro Honkala's contributions to identifying codes

Hudry Olivier, Junnila Ville, Lobstein Antoine

Fundamenta Informaticae

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2024

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Vol. 191, nr 3-4

165--196

EN

A set C of vertices in a graph G = (V, E) is an identifying code if it is dominating and any two vertices of V are dominated by distinct sets of codewords. This paper presents a survey of Iiro Honkala’s contributions to the study of identifying codes with respect to several aspects: complexity of computing an identifying code, combinatorics in binary Hamming spaces, infinite grids, relationships between identifying codes and usual parameters in graphs, structural properties of graphs admitting identifying codes, and number of optimal identifying codes.

5

Study on flotation behavior and mechanism of separating chalcopyrite and Molybdenite with ethyl mercaptoglycolate as inhibitor

Yang Xiao-Feng, Xu-Zhao, Liu Yao-Yao

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 2

art. no. 162824

EN

The effect of ethyl thioglycolate organic small molecule inhibitors on chalcopyrite molybdenite flotation behaviour is investigated via single mineral micro-flotation tests, zeta potential tests, and X-ray photoelectron spectroscopy (XPS) analysis. Results of the flotation test indicate that ethyl thioglycolate organic small-molecule inhibitors can effectively separate Cu and Mo and selectively inhibit chalcopyrite under weak alkaline conditions. Infrared spectroscopy and XPS analysis show that hydrophilic functional groups C=O and -COOH in the ethyl thioglycolate organic small molecules can chemically adsorb onto the chalcopyrite surface. Moreover, ethyl thioglycolate has no obvious effect on zeta potential of molybdenite. Therefore, ethyl thioglycolate can effectively separate chalcopyrite and molybdenite.

6

Separation of molybdenite from chalcopyrite, using graphene oxide as a novel depressant

Namiranian Afshin, Noaparast Mohammad, Tonkaboni Sied Ziaedin Shafaei

Archives of Mining Sciences

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2023

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Vol. 68, no. 1

71--86

EN

In this research, graphene oxide was introduced as an efficient flotation reagent for the selective separation of molybdenite from chalcopyrite. The performance of graphene oxide and its adsorption mechanism on chalcopyrite were investigated by flotation tests, FTIR spectra, and XPS measurements. First, graphene oxide was synthesised, and then its performance was evaluated by SEM, XRD, and EDX. Flotation tests were carried out in a hallimond flotation cell with a volume of 300 ml. Optimum flotation values were achieved at pH = 9 by adding 250 g/t of PAX (Potassium Amyl Xanthate) as a collector and 50 g/t of A65 (Poly Propylene Glycol) as a frother. The results showed high recovery, around 80% for molybdenite, while chalcopyrite was depressed in high amounts by employing 11 kg/t of graphene oxide as a depressant. Compared to common chalcopyrite depressants such as NaHS, Na2S, and C2H3NaO2S, graphene oxide had a higher potency in depressing, which can be applied as a green-depressant in the separation of molybdenite from chalcopyrite by the flotation process. Also, the validity of the depressing effect on chalcopyrite was verified by XPS and FTIR spectra.

7

Separation of ampicillin on polar-endcapped phase : development of the HPLC method to achieve its correct dosage in cardiac surgery

Kubickova Vendula, Racova Zuzana, Strojil Jan, Santavy Petr, Urbanek Karel

Acta Chromatographica

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2023

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Vol. 35, no. 1

1--9

EN

The accurate, simple, and selective reversed phase high performance liquid chromatography (RP-HPLC) has been established and validated for the determination of an antibiotic ampicillin (AMP) in human blood plasma. The SPE extraction was used for the sample preparation. Chromatographic separation was accomplished by a mobile phase containing 15 mM monopotassium phosphate solution of pH 3.3 and methanol (75:25, v/v) in an isocratic mode at a flow rate of 1.4 mL min⁻¹ at 30 °C. The separation was evaluated on a column with a new polar-endcapped C18 stationary phase Arion® Polar C18 or well-known phase Luna® Omega Polar C18. Excellent linearity (R2 0.9998) was shown over range 10–300 mg L⁻¹ with mean percentage recovery 90%. Peak shapes were symmetrical in both columns, Arion® Polar C18 and Luna® Omega Polar C18, with asymmetry factor of 1.0 and 1.4, tailing factor of 1.0 and 1.2, and retention factor of 4.6 and 5.6, respectively. The Arion® Polar C18 was almost 1.4-fold more effective than Luna® Omega Polar C18 phase. The LOQ for ampicillin was achieved 10 mg L⁻¹ for Luna® Omega Polar C18 and 5 mg L⁻¹ for Arion® Polar C18 using 20 µL of a solution containing 0.24 mg mL⁻¹ of cephalexin as an internal standard. A number of articles dealing with the determination of ampicillin is limited, therefore, this study showed the HPLC method suitable for the determination of AMP in human blood plasma from patient who underwent elective cardiac surgical revascularization. In addition, the determination of AMP was also performed for the first time using an Arion® Polar C18 column, which effectively separated AMP from other compounds present in human blood plasma. This new polar-endcapped phase can help in separation of polar antibiotics or other polar compounds, which are unsuccessfully separated on conventional C18 column, and thus can help during method development.

8

Recovery of pure palladium compound from the spent electroplating solutions by hydrometallurgical method

Nguyen Viet Nhan Hoa, Song Si Jeong, Lee Man Seung

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 1

88--100

EN

Electroplating of palladium (Pd) is practiced in the manufacture of electronic materials. The increasing demand for Pd metal necessitates the recovery of Pd(II) from the spent electroplating solutions. In this work, the recovery of Pd compound was studied from the cemented Pd by zinc (Zn) metal from spent electroplating solutions. Initially, the selective extraction ability of ionic liquids synthesized from commercial extractants for Pd(II) over Zn(II) from the synthetic HCl solution was investigated. Pd(II) was selectively extracted over Zn(II) from 9 M HCl solution by ALi-CY301(Nmethyl-N,N,N-trioctylammonium bis(2,4,4-trimethylpentyl) dithiophosphinic) and by ALi-I (N-methylN,N,N-trioctylammonium iodide) from weak HCl solution (pH 1). Since 9 M HCl was needed to completely dissolve Pd from the cemented Pd, ALi-CY301 was employed for the separation of Pd(II) and Zn(II) from the real HCl leaching solution of the cemented Pd. Two-stages counter-current extraction of the real HCl solution with ALi-CY301 resulted in selective extraction of Pd(II). Pd(II) was effectively stripped from the loaded ALi-CY301 by a mixture of HCl and NaClO. After oxidizing Pd(II) in the stripping solution to Pd(IV) by adding NaClO, Pd(IV) compound was synthesized by adding NH4Cl as a precipitant. By comparing leaching and extraction efficiency between hydrochloric and sulfuric acid solutions, a hydrometallurgical process consisted of HCl leaching, extraction with ALiCY301 and precipitation with NH4Cl was recommended for the recovery of pure (NH4)2PdCl6 from the cemented Pd.

9

Ultrasonic treatment and its applicability for the selective treatment of borax clayey waste sludge

Gürsoy Yaşar Hakan, Kurama Haldun

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 5

80--90

EN

Sludge treatment is one of the most difficult challenges for many industrial plants. In recent years, the use of ultrasound power has received considerable attention as one of the increasing tool for managing of this problem. Power ultrasound enhances chemical and physical changes in a liquid medium through the generation and subsequent destruction of cavitations bubbles. Therefore, the increased friction and stress in solution resultant with cleaning of the solid surfaces and dispersion of bonded/aggregated solid particles. In this study, the basic fundamentals of ultrasonic treatment and process variables were briefly overviewed. The study was also extended with preliminary analyses performed to determine its ability on the extraction of major and trace elements from Kırka Borax Concentrator tailings mainly boron as boric acid and Li as Li reach pregnant solution (PLS). Prior and after the sonification tests, physical, chemical and morphological analyses were carried out to determine the treatment performance. It was found that sonication leads the liberation of boron minerals from sludge and with the help of temperature they are dissolved and re-crystallized on clay substrate during cooling stage. The extraction test performed with these crystals revealed that Li-rich solution (that can be further use as source of lithium carbonate or lithium hydroxide production), and boric acid could be produced with easy and low cost beneficiation method.

10

Physical and chemical processes of Abu Rusheid cataclastic rocks for recovering niobium, zirconium and uranium compounds

Abdellah Walid Mahmoud, Khalafalla Mahmoud Sayed, Abu Khoziem Hanaa Abdelaal, El Hussain Omneya Mouhamed

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 5

137--152

EN

Cataclastic rocks of Abu Rushied area (South Eastern Desert, Egypt) characterized by the presence of niobium, tantalum, zirconium minerals as well as uranium-thorium minerals. Physical upgrading process was applied using gravity and magnetic separation techniques to concentrate these economic minerals mainly to obtain the magnetic niobium concentrate at 0.2- 0.5 ampere, beside the non-magnetic Zr and U at 1.5 ampere. The chemical processing upon niobium concentrate was performed using NH4F roasting process at 250ºC followed by selective precipitation of Nb as Nb-sulfide. An alkaline fusion using NaOH was applied upon zirconium concentrate at the optimum conditions of: zircon concentrate/ NaOH mass ratio 1/2, fusion temperature of 650ºC and 2.5h fusion time followed by selective precipitation of Zr as Zr- tartrate. Finally, two flowsheets were drawn summarizing the whole recovery processes.

11

Improvement of metal separation process from synthetic hydrochloric acid leaching solution of spent lithium ion batteries by solvent extraction and ion exchange

Nguyen Viet Nhan Hoa, Lee Man Seung

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 4

1--17

EN

Spent lithium-ion batteries (LIBs) are good secondary resources for recycle and reuse. To develop a process for the separation of Cu(II), Co(II), Mn(II), Ni(II) and Li(I) with high purity from spent LIBs and circumvent some drawbacks of the previous work, solvent extraction and ion exchange experiments were done in this work. The synthetic hydrochloric acid leaching solution of 3 M was employed. Compared to Aliquat 336 (N-Methyl- N, N, N-trioctyl ammonium chloride), extraction with Cyanex 301 (bis(2,4,4-trimethylpentyl) dithiophosphinic acid) led to selective extraction of Cu(II) over other metal ions. Employing ion exchange with TEVA-SCN resin can completely separate Co(II) over Mn(II). After adjusting the pH of Co(II) free raffinate to 3, Mn(II) was quantitatively extracted by the mixture of Alamine 336 (mixture of tri-octyl/decyl amine) and PC 88A (2-ethylhexyl hydrogen-2-ethylhexylphosphonate) with two stage cross-current extraction. The synthesized ionic liquid (ALi-CY) was used for complete extraction of Ni(II), whereas Li(I) remained in final raffinate. The metal ions in the loaded organic phase were completely stripped with the proper agents (5% aqua regia for Cu(II), 5% NH3 for Co(II), weak H2SO4 solution for Mn(II) and Ni(II) stripping, respectively). The experimental results revealed that purity of the metal ions in stripping solution was higher than 99.9%. A flowsheet was suggested to separate metal ions from the HCl leaching solutions of spent LIBs.

12

Comparing automatic baseflow separation filters on three watersheds in the urbanised area of East Java, Indonesia

Indarto Indarto, Hardiansyah Mujiono, Sujarwo Mohamad Wawan

Journal of Water and Land Development

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2021

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no. 50

130--140

EN

Baseflow is the primary source of water for irrigation and other water needs during prolonged dry periods; accurate and rapid estimation of baseflow is therefore crucial for water resource allocation. This research aims to estimate baseflow contribution during dry periods in three small watersheds in East Java: Surabaya-Perning (114 km2), Lamong-Simoanggrok (235 km2), and Bangsal-Kedunguneng (26 km2). Six recursive digital filters (RDFs) algorithms are explored using a procedure consisting of calibration, validation, evaluation and interpretation. In this study, the period of July to September is considered as the peak of the dry season. Moreover, data for the period 1996 to 2005 is used to calibrate the algorithms. By yearly averaging, values are obtained for the parameters and then used to test performance during the validation period from 2006 to 2015. Statistical analysis, flow duration curves and hydrographs are used to evaluate and compare the performance of each algorithm. The results show that all the filters explored can be applied to estimate baseflow in the region. However, the Lyne–Hollick (with RMSE = 0.022, 0.125, 0.010 and R2 = 0.951, 0.968, 0.712) and exponentially weighted moving average or EWMA (with RMSE = 0.022, 0.124, 0.009 and R2 = 0.957, 0.968, 0.891) for the three sub-watersheds versions give the best performance.

13

Automated test bench for research on electrostatic separation in plastic recycling application

Regulski Roman, Czarnecka-Komorowska Dorota, Jędryczka Cezary, Sędziak Dariusz, Rybarczyk Dominik, Netter Krzysztof, Barański Mariusz, Barczewski Mateusz

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 2

art. no. e136719

EN

Many researchers in the developed countries have been intensively seeking effective methods of plastic recycling over the past years. Those techniques are necessary to protect our natural environment and save non-renewable resources. This paper presents the concept of an electrostatic separator designed as a test bench dedicated to the separation of mixed plastic waste from the automotive industry. According to the current policy of the European Union on the recycling process of the automotive industry, all these waste materials must be recycled further for re-entering into the life cycle (according to the circular economy). In this paper, the proposed concept and design of the test bench were offered the feasibility to conduct research and technological tests of the electrostatic separation process of mixed plastics. The designed test bench facilitated assessing the impact of positions of high-voltage electrodes, the value and polarity of the high voltage, the variable speed of feeders and drums, and also triboelectrification parameters (like time and intensity) on the process, among others. A specialized computer vision system has been proposed and developed to enable quick and reliable evaluation of the impact of process parameters on the efficiency of electrostatic separation. The preliminary results of the conducted tests indicated that the proposed innovative design of the research stand ensures high research potential, thanks to the high accuracy of mixed plastics in a short time. The results showed the significant impact of the corona electrode position and the value of the applied voltage on the separation process effectiveness. It can be concluded that the results confirmed the ability to determine optimally the values of the studied parameters, in terms of plastic separation effectiveness. This study showed that this concept of an electrostatic separator designed as a test bench dedicated for separation of mixed plastic waste can be widely applied in the recycling plastic industry.

14

Reduction of carbon footprint from spark ignition power facilities by the dual approach

Janusz-Szymańska Katarzyna, Grzywnowicz Krzysztof, Wiciak Grzegorz, Remiorz Leszek

Archives of Thermodynamics

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2021

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Vol. 42, no. 2

171--192

EN

Power generation units, suitable for individual users and small scale applications, are mainly based on spark ignition engines. In recently performed research, reductions of emissions coming from such units, especially considering carbon dioxide emissions, are deemed as the issue of particular importance. One of solutions, postponed to reduce impact of spark ignition engine-based units on the natural environment, is transition from fossil fuels into renewable gaseous fuels, as products of organic digestion. Nonetheless, development of new solutions is required to prevent further carbon dioxide emissions. The paper presents a novel dual approach developed to reduce carbon dioxide emissions from stationary power units, basing on spark ignition engine. The discussed approach includes both reduction in carbon content in the fuel, which is realized by its enrichment with hydrogen produced using the solar energy-supported electrolysis process, as well as application of post-combustion carbon dioxide separation. Results of the performed analysis suggest profitability of transition from fossil into the hydrogen-enriched fuel mixture, with significant rise in operational parameters of the system following increase in the hydrogen content. Nevertheless, utilization of the carbon dioxide separation leads to vital soar in internal energy demand, causing vital loss in operational and economical parameters of the analyzed system.

15

Separation of surface flow from subsurface flow in catchments using runoff coefficient

Ardekani A. Afshar, Sabzevari T., Haghighi A. Torabi, Petroselli A.

Acta Geophysica

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2021

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Vol. 69, no. 6

2363--2376

EN

Separating surface flow (SF) from subsurface flow (SSF) based on direct runoff measurements in river gauges is an important issue in hydrology. In this study, we developed a simple and practical method, based on runoff coefficient (RC), for separating SF from SSF. RC depends mainly on soil texture, land use and land cover, but we also considered the effect of slope and rainfall intensity. We assessed our RC-based method for three different soil types by comparing the value obtained with laboratory rainfall simulator data. The correlation coefficient between observed and calculated data exceeded 0.93 and 0.63 when estimating SF and SSF, respectively. The method was then used to separate SF and SSF in two catchments (Heng-Chi and San-Hsia) in Northern Taiwan, and the results were compared with those produced by the geomorphological instantaneous unit hydrograph (GIUH) model. Test revealed that, if RC is calculated accurately, the proposed method can satisfactorily separate SF from SSF at catchment scale.

16

New conditions of HPLC analysis for separation and quantification of simple organic acids of tricarboxylic acid cycle in psoriasis

Fan Jiaxing, Liu Yiyang, Su Shenmin, Cao Yiqing, Yu Yunqiu

Acta Chromatographica

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2021

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Vol. 33, no. 4

322--332

EN

Tricarboxylic acid cycle is an important pathway and the metabolites of tricarboxylic acid cycle, simple organic acids, play important roles in many physiological processes. The new conditions of high performance liquid chromatography (HPLC) with improved separation selectivity were developed and optimized by choosing suitable store solvent, methanol, which can catalyze the reaction, aldol condensation, and facilitate the formation of new compound to improve simultaneous detection of nine metabolites of tricarboxylic acid cycle, including lactic acid, pyruvic acid, citric acid, alpha-ketoglutaric acid, malic acid, succinic acid, cis-aconitic acid, itaconic acid, and fumaric acid, and be applied in analysis of the nine metabolites in psoriasis mice skin. This study shows that in process of developing methods, expect conventional chromatographic condition, solvent should also be considered carefully.

17

Separation of Co(II), Cu(II), Ni(II) and Mn(II) from synthetic hydrochloric acid leaching solution of spent lithium ion batteries by solvent extraction

Nguyen Viet Nhan Hoa, Lee Man Seung

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 4

699--610

EN

Spent lithium ion batteries contain valuable critical metals such as cobalt, copper, lithium and nickel. In order to develop a process for the separation of the divalent metal ions from spent lithium ion batteries, solvent extraction experiments were performed by employing synthetic hydrochloric acid leaching solution. The synthetic solution contained Cu(II), Co(II), Mn(II) and Ni(II) and its acidity was 3 M HCl. Extraction with Aliquat 336 led to selective extraction of Cu(II) with a small amount of Co(II). After adding NaCl to the Cu(II) free raffinate to enhance the complex formation of Co(II), Co(II) was selectively extracted into Aliquat 336 together with Mn(II). The small amount of Mn(II) in the loaded Aliquat 336 was scrubbed by pure Co(II) solution. After adjusting the pH of the raffinate to 3, 91,3% of Mn(II) was selectively extracted over Ni(II) by the mixture of D2EHPA and Alamine 336. In this extraction, the mole fraction of D2EHPA in the mixture affected the extraction of Mn(II). McCabe-Thiele diagrams for the extraction of Cu(II) and Co(II) were constructed. Batch simulation experiments for the three stage counter-current extraction verified the selective extraction of the target metal ions in each extraction step. Namely, the total extraction percentage of Cu(II) and Co(II) was 71.6% and 98.8% respectively. Most metals in the loaded organic phase were stripped completely with the appropriate agents (1.0 M H2SO4 for Cu(II), 0.1 M H2SO4 for Co(II) and 0.3 M HCl for Mn(II) stripping). A process was proposed to separate the metal ions by solvent extraction.

18

Application of multiple linear regression (MLR) analysis for concentration of chromite tailings by the flotation

Deniz Vedat

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 4

579--589

EN

In this study, the concentration of chromite minerals by amine flotation of a chromite tailing (slime) with content 23.84% Cr2O3 from Yeşilova-Burdur (Turkey) was investigated. In experimental studies, firstly, some operating parameters of the rougher flotation observed for a low-grade chromite tailing were investigated. Secondly, multiple linear regression (MLR) analyses were performed to determine the effects of some operating parameters on the performance of the rougher amine flotation. From the experimental results, multiple linear regression equations were developed to predict the recovery and grade of the chromite concentrate, and the regression coefficients between experimental and predicted values were found to be quite good (R2 values of 0.772 and 0.917, respectively). Additionally, it was found that the conditioning time and low pH value using H2SO4 showed an important effect on the recovery and the grade of the chromite concentrate.

19

The analysis of surface deformation controlled by key strata groups and separation in strip mining

Luan Yuan-Zhong, Li Zeng-Xin, Weng Li-Yuan, Zhang Ming-Xin

Mining Science

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2020

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Vol. 27

303--322

EN

In this paper, the key stratum theory is introduced in view of the small surface deformation value of the mining of thick coal mines in Gucheng Coal Mine. The analysis of geological drilling data in Gucheng Goal Mine determines three key strata groups and one main key stratum for controlling the surface deformation of the stratum above the No. 3 coal according to the stiffness and strength condition of the stratum. The breaking distance of the main key stratum in this Mine is determined to be 302–373.7 m in terms of the elastic foundation beam theory and the surface measured basin data. In addition, a large-scale separation model of the main key stratum of the five strip mining face of this Mine is established, and the quantitative calculation formula of the limit spanning of rock beam is proposed and applied to. Finally, the probability integral method is used to predict the surface deformation problem of multiple working faces, and the partition prediction is performed according to the key stratum breaking distance to obtain prediction values of surface deformation consistent with the fracture of key stratum in the study area.

20

Tests of neodymium content in selected materials

Friebe Paweł

Mining Machines

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2020

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no. 2

38--47

EN

Rare earth elements are recognized as Critical Raw Materials (CRMs) due to their wide range of applications in the glass, steel, chemical and electronic industries. Often rare earth elements are referred to as a single group, but in practice each element has individual technical applications. Therefore, the demand varies for each element. Demand for rare earth elements is likely to increase in the future due to use of NdFeB magnets, especially in vehicles with electric motors and wind turbines. This publication presents research results aimed at finding raw material or waste that can be used to obtain neodymium at economical profit. This publication presents tests aimed at an identification of the raw material from which neodymium can be obtained. Research began with an identification of materials that could potentially become an economically viable source of neodymium extraction. The following materials were selected: natural aggregates, fine-grained raw materials of magma origin as well as coal sludge and fine-grained waste after hard coal enrichment. These raw materials were subject to content analysis by mass spectrometry, with ionization in inductively compressed plasma (ICP-MS).

PL

Pierwiastki ziem rzadkich zostały uznane w ostatnich czasach jako surowce krytyczne ze względu na ich szeroki zakres zastosowań w przemysłach: szklarskim, stalowym, chemicznym i elektronice. Często pierwiastki ziem rzadkich łączone są w jedną grupę, jednakże w praktyce każdy pojedynczy pierwiastek posiada odrębne zastosowania, dlatego popyt na każdy pierwiastek jest inny. Prognozy wskazują na prawdopodobny wzrost zapotrzebowania na pierwiastki ziem rzadkich, co może być związane między innymi ze zwiększenia stosowania magnesów NdFeB, szczególnie w pojazdach hybrydowych i elektrycznych oraz turbinach wiatrowych. W niniejszej publikacji przedstawiono badania mające na celu zidentyfikowanie surowca, z którego będzie można pozyskać neodym. Badania rozpoczęto od wskazania materiałów, które potencjalnie mogą stać się ekonomicznie uzasadnionym źródłem pozyskiwania neodymu. Wytypowane zostały: kruszywa naturalne, drobnoziarniste surowce pochodzenia magmowego oraz muły węglowe i drobnoziarniste odpady po wzbogacaniu węgla kamiennego. Surowce te zostały poddane analizie zawartości neodymu metodą spektrometrii mas, z jonizacją w plazmie indukcyjnie sprężonej (ICP-MS)