Leaching Of Nickel Research Articles

Synthesis of fatty acid-based ammonium ionic liquids and their application for extraction of Co(II) and Ni(II) metals ions from aqueous solution

Leaching of cobalt and nickel into diverse water streams has become an environmental hazard and is continuously impacting human health through the food chain. Solvent extraction is the most widely accepted for separating these metals, but traditional extractants employed in conjunction with molecular diluents often lack selectivity and caused major environmental hurdles. Therefore, the development of cost-effective, environmentally friendly technologies for recovering these heavy metals has been strongly encouraged in recent years. Herein, two halogens free, low viscous, biocompatible fatty acid-based hydrophobic ionic liquids (ILs), i.e., methytrioctylammonium oleate, methytrioctylammonium linoleate were synthesized, analytically characterized and employed for recovery of cobalt, Co(II) and nickel, Ni(II) from their aqueous solutions. Extraction behaviour of Co(II) and Ni(II) was further evaluated by varying equilibrium time, ILs molar concentration, metal loading, and temperature. Thermodynamic parameters such as enthalpy change and Gibbs free energy change were also studied during extraction process. Slope analysis suggested that the extraction mechanism was an exothermic process that followed ion-transfer from the aqueous phase to the organic phase. Results showed that both fatty acid based–ILs were found to be capable of extracting >99% of Co(II) and Ni(II) from aqueous solutions at 298 K, in 15 min of shaking time using a 1:1 (org: aq.) ratio at low concentrations of 2.5–10 g L−1. Furthermore, for methyltrioctylammonium oleate IL, Co(II) extraction was selectively preferred over Ni(II) extraction when the metal concentration was increased to above to 10 g L−1. The stripping results showed that 2 M H2SO4, and 2 M HCl successfully stripped out >99% of Co(II) and Ni(II) from the organic phase, respectively compared to HNO3.

Carbon(sp2)‐carbon(sp3) Bond‐forming Cross‐coupling Reactions Using Sulfur‐Modified Au‐Supported Nickel Nanoparticle Catalyst

AbstractWe report a carbon(sp2)‐carbon(sp3) bond‐forming cross‐coupling reactions by employing a nano‐size nickel catalyst supported on sulfur‐modified gold (SANi). This transformation demonstrates an efficient synthesis of functionalized aryl compounds, including heterocycles. Notably, the reactions proceeded in good yields with significantly low leaching of nickel from SANi. Moreover, SANi could be recycled several times without significant loss of catalytic activity.

Kinetics Study of Leaching Ore Nickel Laterite Using Hydrochloric Acid in Atmosphere Pressure

Leaching of nickel laterite ore at atmospheric pressure is a leaching method that can be operated at >100⁰C temperatures in an atmospheric pressure, which is applicable to a low-grade laterite ore. This research aimed to study the effect of temperature, acid concentration, and leaching time on nickel extraction percentage and the leaching kinetics. Hydrochloric acid (HCl) was used as a leaching agent and several variables were applied, i.e., temperature (80⁰C, 90⁰C, 100⁰C), HCL concentration (5 M, 6 M, 7 M), and leaching duration (120 minutes, 150 minutes, 180 minutes) to investigate their effect on nickel extraction percentage. In addition, the kinetics of the leaching process was studied using a Shrinking Core Model. The results showed that the percentage of nickel extraction increased with increasing temperature, HCl concentration, and leaching time. The lowest percentage of nickel extraction of 51.29% was obtained when 80⁰C, five molar HCl, and 120 minutes leaching duration were applied. In contrast, The highest percentage of nickel extraction of 97.22% was obtained at 100⁰C, seven molar HCl, and 180 minutes of leaching time. The kinetics study results show that diffusion through the unreacted solid product layer controls the nickel leaching rate.

Metal leaching test of commercially available faucets in the Japanese market in 2016-2020.

In this study, metal leaching was investigated in commercially available faucets in Japan to clarify their compliance to Japanese regulations. We purchased 37 faucets from the market and analyzed the leaching of cadmium, mercury, selenium, lead (Pb), arsenic, hexavalent chromium, boron, zinc (Zn), copper, manganese, and nickel. The leaching tests were performed with and without a conditioning treatment, that simulated approximately 1-month intermittent use of faucets on weekdays, and the results were compared to estimate the changes in metal leaching during the use of faucets. The results revealed that metal leaching from most of the faucets complied with Japanese regulations. However, the levels of Pb leaching from several faucets produced by certain manufacturers exceeded the Japanese standard. The conditioning treatment was generally effective in reducing metal leaching. However, the reductions in Pb and Zn leaching tended to be lower than those of the other metals. Nickel is not legally regulated in Japan; although the number of cases where nickel concentration in leachate exceeded the water quality management target value was greater, such cases were limited to faucets primarily made of copper alloys. We believe that these results will be helpful to improve the public health associated with metal leaching from faucets.

Dissolution behavior and porous kinetics of limonitic laterite during nitric acid atmospheric leaching

In our previous study, the mineral evolution and porous kinetics during nitric acid pressure leaching of limonitic laterite has been investigated. In order to optimize the nitric acid leaching technology, this paper investigated the dissolution behavior and porous kinetics of limonitic laterite during nitric acid atmospheric leaching. The experimental results showed that Ni and Fe had consistent leaching behavior, whereas Co was only consistent with Mn in the early stages of leaching. The DFT (Density functional theory) simulations of goethite dissolution revealed that H+ attacked the bridging O first with adsorption energy of −1.37 eV, while NO3– attacked the Fe with adsorption energy of −3.07 eV, hence promoting the dissolution of Fe from the goethite crystals. Based on meticulous modeling analysis, the leaching of Ni could be described by grain model-cylindrical particle. In the early stage of leaching, the Ni extraction is regulated by chemical reactions with an activation energy of 88.4 kJ/mol. In the latter stage, the leaching is regulated by pore diffusion with an effective diffusivity of 1.37 × 10-11 m2/min at 90 °C. This study clarified the dissolution behavior of limonitic laterite, and described nickel leaching using a porous kinetic model.

The Design of Ternary Composite Polyurethane Membranes with an Enhanced Photocatalytic Degradation Potential for the Removal of Anionic Dyes

Photocatalysis is an efficient and an eco-friendly way to eliminate organic pollutants from wastewater and filtration media. The major dilemma coupled with conventional membrane technology in wastewater remediation is fouling. In this study, the photocatalytic degradation potential of novel thermoplastic polyurethane (TPU) based NiO on aminated graphene oxide (NH2-GO) nanocomposite membranes was explored. The fabrication of TPU-NiO/NH2-GO membranes was achieved by the phase inversion method and analyzed for their performances. The membranes were effectively characterized in terms of surface morphology, functional group, and crystalline phase identification, using scanning electron microscopy, Fourier transformed infrared spectroscopy, and X-ray diffraction analysis, respectively. The prepared materials were investigated in terms of photocatalytic degradation potential against selected pollutants. Approximately 94% dye removal efficiency was observed under optimized conditions (i.e., reaction time = 180 min, pH 3–4, photocatalyst dose = 80 mg/100 mL, and oxidant dose = 10 mM). The optimized membranes possessed effective pure water flux and excellent dye rejection (approximately 94%) under 4 bar pressure. The nickel leaching in the treated wastewater sample was determined using inductively coupled plasma-optical emission spectrometry (ICP-OES). The obtained data was kinetically analyzed using first- and second-order reaction kinetic models. A first-order kinetic study was suited for the present study. Besides, the proposed membranes provided excellent photocatalytic ability up to six reusability cycles. The combination of TPU and NH2-GO provided effective strength to membranes and the immobilization of NiO nanoparticles improved the photocatalytic behavior.

Comparison of Bio- and Ferric Leaching for Beneficiation of Bulk Copper-Nickel Sulfidic Concentrate

Processing of sulfidic raw materials, including bulk concentrates of nonferrous metals, is a problem of current importance in metallurgy and waste recycling. In this study, leaching with a chemical ferric iron reagent was compared to two bio-approaches to process a bulk copper-nickel concentrate: (1) ferric leaching with a solution obtained by microbial oxidation and (2) stirred-tank bioleaching using an active acidophilic microbial community. The results of both the chemical and bio-processes indicated nickel dissolution, while copper was accumulated in leach residues. After short-term high-temperature leaching with the chemical or bio- solution (Fe3+, 10 g/L), the nickel content in solids decreased by 0.7 and 2.6%, respectively, while the copper content slightly increased (by 1.5–3.2%). Bioleaching at 40°C was characterized by a considerably higher efficacy of the process: nickel leaching reached 86.7%, and the copper content increased by ~5% in the bioleach residue. Based on these results, ferric leaching can be considered an inefficient method for selective nickel removal, while bioleaching may be a promising cost-effective approach characterized by relatively low environmental hazards to obtain a high-grade copper product. Moreover, ferric leaching with the bio-solution can improve the grade of monometallic sulfidic concentrates due to additional selective nickel extraction.

Effect of copper/nickel ratio on the efficiency of biobeneficiation of bulk copper-nickel sulfide concentrates

The dependence of the efficiency of biobeneficiation (via bioleaching) of bulk copper-nickel sulfide concentrates on the ratio of copper to nickel sulfide minerals was studied. The copper content in the concentrates ranged from 10.8 to 19.1% (copper occurred in chalcopyrite), while the content of nickel was within 4.6–9.5% (nickel occurred in pentlandite and violarite). Although the copper content was higher than the content of nickel in all concentrates, the rate of nickel leaching significantly exceeded that of copper leaching. For the concentrates characterized by copper/nickel ratio (k) equal to 1.15 and 1.5, the average nickel leaching rate was ˃8 times higher than the copper leaching rate. Bioleaching of all studied concentrates allowed the obtainment of copper concentrates in solids (copper content of 15.6–18.7%) in which nickel content was low (0.27–1.49%). The high level of nickel dissolution and the maximum increase in the copper content in the solids were shown for the concentrate with the initial copper and nickel content of 10.9 and 7.2%, respectively (k of 1.5). In this bioleach residue, the copper content increased by 4.7%, while the nickel content decreased by 6.86% compared to the original concentrate. Thus, bioleaching of copper-nickel concentrates can be considered biobeneficiation, and the highest efficacy of the process may be achieved at a copper/nickel ratio of ∼1.5.

Priority recovery of lithium and effective leaching of nickel and cobalt from spent lithium-ion battery

The cathode materials of spent lithium-ion batteries (LIBs) were recovered via reductive roasting, Na2CO3 leaching, and ammonia leaching. The effects of roasting parameters, Na2CO3 leaching parameters, and ammonia leaching parameters on the leaching efficiencies of metals were explored. The results show that the mineral phase of spent LIBs is reconstructed during reductive roasting, and more than 99% of Li can be preferentially leached via Na2CO3 leaching. Ni (99.7%) and Co (99.9%) can be leached via one-step ammonia leaching, and Mn cannot be leached. Thus, good leaching selectivity is achieved. The kinetic study shows that the leaching of Ni and Co conforms to chemical reaction control.

Modified Surface Composition and Biocompatibility of Core-Shell Nitinol Nanoparticles Fabricated via Laser Ablation of Differently Passivized Targets

Nitinol is a versatile alloy known for its shape memory effect and thus finds multiple applications in biomedical devices and implants. The biomedical applications of nitinol-based devices are, however, limited because of concerns related to leaching and its associated cytotoxicity. In particular, nitinol nanoparticles (NPs), despite being highly promising for biomedical applications such as nano-actuators and biomolecular delivery agents are not explored, owing to the same concerns. Moreover, nitinol nanoparticles and their biological interactions are not fully characterized, and the available literature on their toxicity portrays a divided picture. Surface passivation of nitinol using multiple methods has been explored in the past to reduce the leaching of nickel in implants while also improving the thrombogenic properties. In this work, we reported the preparation of passivized nitinol NPs by laser ablation of nitinol targets, followed by different surface treatments. The effect of different treatments in reducing nickel leaching and its influence on biocompatibility were studied. The biocompatibility and multi-faceted interaction of nitinol NPs with osteoblast cells and associated toxicity were explored. Homogenous nitinol NPs were found to be generated at 25 W of laser power. Also, surface modification using hydrogen peroxide, anodization, and acid etching was found to be effective in waning the nickel leaching and improving biocompatibility. In view of the observed results of cellular interactions, we discussed the possible routes of cellular toxicity of these NPs. The prospective applications of such passivized NPs in the biomedical field are also discussed in this work.

Prevention of sulfuric acid pollution: intensification of metal leaching with organic acids

Hydrometallurgical mining of valuable and non-ferrous metals is traditionally accompanied by a large-scale pollution of the territories with sulfuric acid. This pollution is the global problem and requires the significant remediation costs. There are known some attempts to replace sulfuric and other strong inorganic acids with organic acids which could be easier utilized under natural conditions. However, this approach proved to be ineffective due to the weak leaching effect of organic acids. In our experiments on chemical leaching, we investigated leaching of nickel from low-grade silicate ores with a mixture of organic acids and persulfate. Organic acids ensured both the acidic reaction of the leaching solution while persulfate provided a short-term formation of persulfuric (peroxysulphuric) acid, which is the stronger leaching agent than sulfuric acid. In whole, experimental results showed that metal leaching can be intensified with application of organic acids.

Sulfuric Acid Granulation of Copper—Nickel Ore Tailings: Leaching of Copper and Nickel in the Presence of Sulfide Oxidation Activators

A laboratory scale study was conducted, aimed at finding an effective method for processing fine concentration tailings of copper-nickel ores. A sulfuric acid tailing granulation process followed by subsequent heap leaching of granules is proposed. Various methods of preparation and storage of the granular material are discussed. A solution of sulfuric acid was used as a binder. It was found that the addition of an oxidizing agent (Fe3+ and NO2−) when irrigating the granules had an effect on the recovery of metals. Changes in the recovery performance of non-ferrous metals into solution were studied under subsequent heap leaching of the material during a period of positive temperatures. The role of nitrogen compounds, in particular, nitrous acid, on the recovery of metals into solution after the preliminary storage of granules at below 0 °C temperatures is also discussed.

Effect of Temperature on Biobeneficiation of Bulk Copper-Nickel Concentrate with Thermoacidophilic Microbial Communities

Bioleaching of the bulk copper–nickel sulfide concentrate was proposed as a method to remove nickel from it and to obtain a concentrate containing copper as chalcopyrite. This approach is based on the different refractoriness of sulfide minerals in ferric sulfate solutions and oxidation by acidophilic microorganisms. The bulk concentrate contained 10.8% copper in the form of chalcopyrite (CuFeS2) and 7.2% nickel that occurred in pentlandite ((Ni,Fe)9S8) and violarite (FeNi2S4). Three microbial communities grown at 35, 40, and 50 °C were used for bioleaching. The microbial community at 40 °C was the most diverse in the genus and species composition. At all temperatures of the process, the key roles in bioleaching belonged to mixotrophic and heterotrophic acidophiles. The highest levels of nickel leaching of 97.2 and 96.3% were observed in the case of communities growing at 40 and 50 °C, respectively. At the same time, the bioleach residue, which could be characterized as a marketable high-grade copper (chalcopyrite) concentrate, was obtained only at 40 °C. This solid contained 15.6% copper and 0.54% nickel. Thus, the biobeneficiation of bulk sulfide concentrates can be a promising field of biohydrometallurgy.

Optimized modelling and kinetic analysis of nickel recovery from waste orthodontic implants using response surface methodology

With the increasing applications of nickel in industrial homogeneous catalysis, coatings, and batteries a large amount can be recycled from waste orthodontic implants that contain ∼ 10% nickel. This research has reported a cost-effective, low temperature, and environmentally friendly route for recovering nickel from the waste orthodontic implants using a hydrometallurgical technique. Response surface methodology coupled with central composition design (CCD) was employed to optimize and maximize the yield. Leaching time, temperature, rotational speed, and solid–liquid (S-L) ratio were considered independent parameters, while recovery of nickel was taken as a response. A quadratic regression model was developed for the maximization of nickel leaching concerning input parameters and response. Different performance indicators (i.e., RE, RMSE, and MAE) were employed to assess the developed model further. Based on ANOVA analysis, temperature, and S-L ratio were found to be statistically significant factors. The results show a maximum nickel yield of ∼95% was achieved with optimized parameters viz., temperature (90 °C), leaching time (180 min), rotational speed (40 rpm), and S-L ratio (1:50). Furthermore, the kinetic analysis of the process is also carried out using the Jander rate equation, and the calculated activation energy of nickel leaching with a first-order reaction is 39.8 kJ/mol.

Optimization of process parameters for the selective leaching of copper, nickel and isolation of gold from obsolete mobile phone PCBs

The sequential separation of base and precious metals from the end-of-life mobile phone printed circuit boards (PCBs) is a significant challenge for the development of recycling process that exhibit material circularity. In this contribution, a simple, eco-friendly, and efficient leaching process is developed for the dissolution of copper and nickel from obsolete mobile phone PCBs to facilitate the isolation of a gold-rich residue. Chemical pre-treatment of downsized PCBs produced a metallic portion for which the leaching parameters for copper and nickel were optimised, including the type of leaching reagent, temperature, time, pulp density and agitation speed. It was found that quantitative dissolution of base metals occurred using 3.0 M nitric acid at 30 °C with a 50 g/L pulp density, 2 h residence time, and 500 rpm stirring speed; under these conditions, no gold was dissolved. Design of Experiment analysis using Response Surface Methodology was also undertaken to validate the process. Finally, the kinetics of the leaching process were studied and shown to conform to the chemically controlled surface reaction model, with activation energies of 39.7 and 18.4 kJ/mol for copper and nickel. Importantly, the leaching process optimised in this work avoids the need for high temperatures and reduces energy consumption and effluent generation, leading to the cleaner processing of obsolete mobile phone PCBs for the separation of gold from the dominant base metals.

Plasma electrolytic synthesis and characterization of oxide coatings with MWO4 (M = Co, Ni, Cu) as photo-Fenton heterogeneous catalysts

Titanium-supported oxide coatings with MWO4 (M = Cu, Ni, or Co) were formed by the single-stage plasma electrolytic oxidation of titanium in alkaline tungstate-phosphate electrolytes with M(II)–EDTA complex ions. All formed coatings exhibited photocatalytic activity in the reaction of degradation of methyl orange (10 mg/L MO, pH = 6.8) in the presence of 10 mmol/L hydrogen peroxide under UV and Vis irradiation. The Ti/TiO2-CoWO4 composite was most effective catalyst: the degree of MO azo dye degradation reached 85 and 55% after 180 min irradiation under UV and Vis light, respectively. The bandgap values determined by the Tauc's method for the direct allowed transition were 2.2, 2.45 and 2.5 eV for Co-, Cu- and Ni-containing samples, correspondingly. The leaching of cobalt, copper and nickel from catalysts during the degradation process was less than 0.88, 0.52 and 1.47 mg/L per cycle, but this fact did not lead to a decrease in MO degradation with the number of cycles. The degradation reaction under UV and Vis irradiation has a first order rate coefficient of (8.9–11.0) × 10−3 and (2.0–8.3) × 10−3 min−1, respectively.

Study on the effect of microwave roasting pretreatment on nickel extraction from nickel-containing residue using sulfuric acid

Abstract Various means have been proposed to solve problems such as high ash content and complex composition in the recycling of nickel-containing residue produced by battery manufacturing enterprises. Microwave roasting pretreatment is proposed to improve the nickel leaching rate from the residue. The effect of different experimental conditions like microwave roasting temperatures, roasting times, and microwave powers on the nickel leaching rate was studied. It was found that the effect of roasting temperature on the nickel leaching rate was more significant than those of roasting time and microwave power. Meanwhile, after microwave roasting pretreatment, the rate of nickel leaching from the residue could be increased by 20.43%, and weight of the material could also be reduced by more than 21%. After microwave roasting at 450°C, there was no significant change in the main phases of the material, but the surface of the particles exhibited an apparent stratified dissociation phenomenon. Response surface methodology (RSM) was used to optimize the parameters of microwave roasting with nickel leaching rate as the response value. The results showed that the nickel leaching rate could reach 93.11% for roasting at the microwave power of 962 W for 6.2 min under the temperature of 452°C.

Kinetics of sulfuric acid leaching of nickel from grinding waste of rhenium-containing superalloys

The paper studies the kinetics of sulfuric acid leaching of nickel, the main component of grinding waste of ZhS-32VI rheniumcontaining heat-resistant superalloy formed during mechanical processing of products and containing such impurities as abrasive materials, oils, ceramics and other contaminants with refractory metal concentration in a solid residue, in agitation mode. The nickel content is 60 %. In addition to nickel, grinding waste contains other metals such as rhenium, chromium, cobalt, tungsten, tantalum, molybdenum, hafnium, titanium, and aluminum. The process of nickel leaching from waste with a sulfuric acid solution was carried out in a thermostated cell at an elevated temperature (55–85 °С), waste : 3 M H2SO4 solution phase ratio of 1 g : 10 ml, and stirring rate of 200 min–1. Kinetics was studied using a fraction of –0.071 mm with the highest yield (49.2 wt.%) in grinding waste. Convex kinetic curves of nickel leaching from waste were obtained. It was found that when the temperature changes from 55 to 85 °С, the time until leaching stops decreases from 220 to 140 min, and nickel recovery from the solution increases from 45 to 99 %. The data of the obtained kinetic curves were linearized according to the «contracting sphere» equation, Gistling–Braunstein and Kazeev–Erofeev equations (the latter is most suitable for description). Taking into account the assessment of anamorphosis correlation coefficients, it was found that nickel leaching from grinding waste is limited by the chemical reaction, and the process proceeds in the kinetic region of the reaction. The apparent activation energy calculated using the Arrhenius equation and rate constants obtained by processing linearized kinetic curves according to the «contracting sphere» model, was 47.5±0.5 kJ/mol. This value confirms the course of the process in the kinetic region where the process can be intensified by increasing its temperature.

Leaching kinetics of low nickel matte in an aqueous solution of sulfuric acid saturated with FeSO4 and NiSO4

In the previous study of our group, the low nickel matte was leached directly using H2SO4 under atmospheric pressure. As long as the acidity of the solution was high enough, the high-efficiency leaching of iron, cobalt and nickel can be realized. Moreover, the cuprous sulfide and precious metals cannot be decomposed by H2SO4 and were enriched in the leach residue. Due to the high concentration acid used in the leaching process of low nickel matte, the residual acid in leaching solution may need to be neutralized firstly before the subsequent metal separation. However, a lot of alkali will be consumed, resulting in the formation of harmful inorganic salts. In the experiments, we found that sulfate in the leaching solution could reach saturated and continuously crystallized out under the condition of high concentration of sulfuric acid. Based on the above considerations, the crystallization method may be a choice. Upon combination of the leaching and crystallization process, a new way to extract valuable metals and effectively recycle the sulfuric acid was proposed. However, the dissolution of low nickel matte will be also affected when the solution is saturated. Therefore, it is necessary to explore the leaching behavior of low nickel matte in the presence of solutions saturated with sulfate. In this study, the leaching kinetics of low nickel matte in H2SO4 solutions saturated with FeSO4 and NiSO4 was investigated. Kinetic data of the dissolution of nickel for various parameters showed best fit to the kinetic model governed by diffusion in the inert porous media. The results shown that the reaction order of H2SO4 was 3.02 and the activation energy of the system was found to be approximately 48.7 kJ·mol−1. Compared with sulfuric acid leaching, the reaction order of this study increased greatly, which indicated that the influence of acid concentration on leaching process increased. In addition, the decrease of activation energy showed that the oversaturated sulfate solution leaching process was consistent with the internal diffusion control, which may be because the existence of crystal had an effect on the diffusion of H+ ions in pores.

Bacterial leaching of copper, zinc, nickel and aluminum from discarded printed circuit boards using acidophilic bacteria

Bacterial leaching of copper, zinc, nickel and aluminum from discarded printed circuit boards using acidophilic bacteria