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In this study, recovery of copper from solid material (obtained by leaching of chalcopyrite with oxalic acid in the presence of hydrogen peroxide) with a copper oxalate structure was carried out selectively using HCl. The chemical composition of the solid was as 29.3%, 9.7%, and 13.3% for Cu, Fe, and S, respectively. Selective recovery of copper by degrading the copper oxalate structure with a low-solubility product (Ksp = 4.43 × 10−10) was performed by conventional leaching in the presence of HCl. The optimum leaching conditions were determined as 5 M of HCl concentration, 318 K of leaching temperature, 120 min of leaching time, 25 ml/g of liquid–solid ratio and 400 rpm of stirring speed. Under these conditions, approximately 77% of copper and 3% of iron were taken into the solution. According to the characterization of the leach residue that was obtained, the oxalate structure was degraded. Moreover, the results of XRD analysis showed that the sulfur (S) and cubanite (CuFe2S3) phases were mostly observed in leaching residues, and this was supported by the SEM-EDX data. Based on the results, it may be stated that selective copper extraction can be obtained from a chalcopyrite concentrate by a two-step leaching method using a conventional hydrometallurgical technique.

ABSTRACT Lightweight bricks can be produced by mixing the expanded perlite, CMC, coal dust and water. However, it may not achieve some of the physicomechanical properties. Therefore, colemanite is chosen [...]

Bi2Ca2−xNaxCo2Oymaterials with x=0≤x≤0.125, have been prepared either by sintering through the classical ceramic method, or textured using the laser floating zone technique. XRD results have shown that Bi2Ca2Co2Oyphase is the major one, independently of the Na content, in both kind of samples. SEM studies have shown a drastic microstructural modification between sintered and laser-textured materials. Na-doping increases density and grain sizes in sintered materials, while it enhances grain alignment in laser-grown materials. Moreover, it decreases secondary phase content in all cases. Electrical resistivity is also drastically reduced through texturing, when compared to the sintered samples, and Na-doping further decreases it. The lowest values determined in the laser-textured samples (26mΩcm at 650°C) are around 40% lower than the best in sintered materials. On the other hand, S has been only slightly affected for Na-doping or processing method for all samples. Consequently, the highest power factor at 650°C (0.18mW/K2m) has been obtained in laser-grown 0.075Na-doped samples, which is around 20 and 70% higher than the measured in undoped laser-textured samples, and sintered ones, respectively.

A novel shaped metamaterial sensor application which is designed to operate in X band is proposed. A new sample holder for easy operation is designed and placed just behind the proposed structure in X band. Since the adulteration of fuel with kerosene and ethanol is known method. This study is developed to give an alternative approach to the adulteration sensing studies. By having higher quality factors and wider bandwidth, when it is compared with similar metamaterial studies, proposed structure and design have lots of advantages as resolution, sensitivity and quality factor. Validation of the proposal has been performed in three steps, these steps are dielectric constant measurement by using Agilent 85070E dielectric measurement kit, simulation of the studies and experimental test study of the proposed structure with sensor layer. Obtained results shows us that this proposal can easily be adapted for different electrochemical sensing applications, if the dielectric constant is changing from 2 to 6. Another novel side of this study is application different type of adulteration examples as kerosene and ethanol as well as olive oil adulteration with cotton oil, presents mass application of metamaterials.

Although the water chemistry in saline lakes can differ drastically due to subtle differences in inflowing water conditions, the concentrations, distributions, and geochemical behaviors of trace elements in such environments are poorly understood. In this study, the influence of major‐ion chemistry on the trace element distribution in saline lakes is examined based on major and trace element concentrations and geochemical modeling in three carbonate‐rich saline lakes located in Mongolia and Turkey. The results are compared to data reported from other carbonate‐rich and carbonate‐depleted lakes. The concentrations of U and oxyanions (V, Mo, and W) in carbonate‐rich saline lakes are several orders of magnitude higher than their contributing rivers and seawater. By contrast, their concentrations in carbonate‐depleted saline lakes are lower than those in rivers and oceans. The high U concentrations in carbonate‐rich saline lakes are possibly attributed to the formation of (magnesium–)uranyl–carbonate complexes, and the high oxyanion concentrations are likely a result of the high pH of lake water preventing them from being adsorbed onto solid phases such as suspended particulate matter and sediment. Strontium and Ba concentrations are lower in carbonate‐rich saline lakes than in river water and seawater, but relatively higher in carbonate‐depleted lakes. Incorporation into aragonite and/or calcite, adsorption onto solid phases, and formation of carbonate minerals are possible mechanisms that may account for the lower concentrations of these elements in carbonate‐rich lakes. These results help elucidate the influence of water chemistry on trace element distribution in saline lakes.

Background: Amorphous silica is widely used in cement and ceramic industry and also for the synthesis of many advanced materials. Method: Generally, it is produced using sol-gel and precipitation method. In the present study, amorphous SiO2 was extracted from acidic pumice collected from Van Basin in Turkey by alkaline treatment method. Result: The identification and chemical compositions of the acidic pumice and the amorphous SiO2 were determined by XRD, FTIR, XRF and BET. Conclusion: The results showed that highly pure amorphous silica powder having a remarkable surface area (358 m2/g) with meso-pore structure was successfully extracted from the acidic pumice samples.

Aims: In this study, copper extraction was investigated from chalcopyrite concentrate with hydrogen peroxide and acetic acid mix solution by using response surface methodology. Method: Experiments were planned using Box-Behnken in which various parameters such as leaching time, leaching temperature, H2O2 concentration, liquid-solid ratio, and stirring speed were defined as independent variables. Result: Under optimum experimental conditions, more than 80% of the copper was extracted with R2 value of 0.94 which indicates good fitness of the model. Conclusion: Moreover, other parameters except stirring speed were determined to be linearly effective on the result.

Utilizing the synthetic waste of firefighter costumes, rod‐shaped hard carbon materials are effectively produced for the first time with over 99% purity, and their structural properties are evaluated using the appropriate spectroscopic techniques. The galvanostatic cycling tests are performed at different temperatures and the result shows that the capacity and capacity fade values are directly affected by the temperature. The high‐rate consumption of sodium ions during the evolution of the solid–electrolyte interface in the first cycle of the cells is observed and the highest capacity of the half cells is obtained as 410 and 233 mAh g−1for the first and second cycles, respectively. To compensate for the sodium‐ion loss, an electrochemical treatment presodiation technique is implemented, which is an effective means of compensating for the initial inefficiency. The optimum presodiation condition of electrochemical treatment of anode electrode for the production of Na0.67Mn0.5Fe0.45Ti0.07O2/presodiated hard carbon full cells is investigated. The highest capacity values for C/10 are obtained at 114.9 mAh g−1for the full cells using the voltage window of 2–4 V. The cost analysis of the battery pack for 90 kW electric‐powered cars is calculated by the BatPaC software and the results are evaluated for possible commercialization. The waste firefighter suit is one of the promising materials for the production of hard carbon due to the production of cycling materials for Na‐ion battery cells. High‐performance full Na‐ion batteries can be obtained by pre‐sodiated anodes through an electrochemical process. The cost analysis of the Na‐ion cells for electric cars can be achieved by the BatPac program.

Effective exploitation of the electronic properties of graphene in aqueous medium has been limited due to lack of information about its wettability characteristics. In this paper, fundamental wettability studies of the face and edge planes of graphene were accomplished through contact angle measurements of the as-received and oxidized surfaces. Further, Raman spectroscopic studies were performed to analyze the effect of oxidation on the graphene surfaces based on the D and G bands. Atomic force microscopy (AFM) was used for surface force measurements to determine the iso-electric point (IEP) of the face and edge surface. The interaction of hydrophobic fullerene and hydrophilic fullerol nanoparticles on the graphene face and edge surfaces was studied through AFM imaging. The zeta potential measurements of the above mentioned carbon nanoparticles were also carried out to confirm that the interaction was due to hydrophobic or hydrophilic forces and not due to electrostatic interactions. In addition molecular dynamics and ab-initio simulations were also carried out to verify the interactions of the carbon nanoparticles with the graphite surfaces.

Wind power forecasting's (WPF) technical improvements exhibit that the smooth forecasting of wind power is essential in executing operational management like energy balance, grid reliability, scheduling maintenance, and selection of site location for investment. However, there seems to be a lack of detailed work to guide researchers working on WPF applications and technical challenges. In the current study, a significant number of scientific studies have been reviewed and evaluated as references to help and guide researchers working in this field. Detailed content about the development of WPF, power system operation, and sectorial contributions are presented in this article. In power system operation, the operations like day‐ahead operation and operation day are expressed in the event of WPF. The contributions and key factors of WPF in the energy sector are listed in trend technologies, employment, marketing, and power plants. Then, requirements and technical challenges affecting WPF are considered in terms of application requirements, regulatory requirements, atmospheric challenges, and operational difficulties. Subsequently, the process applications of WPF are handled to give detailed information for researchers and engineers working in WPF. Lastly, the applications like observing and tracking, technical planning, and investment issues are explained. Wind power forecasting provides the contributions like balancing the power system and mitigation of penalties, scheduling the maintenance of wind power plants, investment regarding site location, and technoeconomic and socioeconomic benefits. The current study handles the development stages, power system operation, and sectorial contributions of wind power forecasting in detail.