Search Results (42)

This paper presents a novel approach for the recycling of spent anodic plates from lead-acid batteries through the melt quenching method using iron and calcium oxides and iron powder. The resulting recycled samples, with a 3CaO·5Fe₂O₃·xFe·(92 − x)Pb composition, where x = 0, 1, 3, 5, 8, 10, 15, and 25% mol Fe, were characterized and analyzed in terms of their electrochemical performance. X-ray diffractograms show vitroceramic structures with varied crystalline phases. Analysis of the IR (infrared spectra) data shows a decrease of sulphate units due to doping with iron content. The ultraviolet–visible (UV-Vis) and electron spin resonance (ESR) data reveal the presence of Fe³⁺ ions with varied coordination geometries. Cyclic and linear sweep voltammograms demonstrate that the samples with 8 and 10% Fe exhibit superior electrochemical performance compared to other vitroceramics. The electrochemical impedance spectroscopy measurements indicate that the sample with 8% Fe had lower resistance compared to other analogues and had enhanced electrical conductivity. Full article

The recycling of spent automotive batteries is essential for minimizing their environmental impact. This requires eco-innovative methods with low cost and energy use. The present study explores the recycling of battery electrodes through the melt quenching method, a process that incorporates spent anode and cathode plates into a vitreous host matrix. Samples with the xCuO·10Sb₂O₃·(90 − x)[4PbO₂·Pb] composition, where x = 0 to 30 mol% CuO, were prepared by the melt quenching method. The XRD analysis indicates the vitroceramic structures of the obtained samples. Thus, the presence of varied crystalline phases such as Pb₂(SO₄)O, PbSO₄, and metallic Pb was detected. The SEM micrographs highlighted heterogeneous regions within the samples and showed a decreases of the size of crystallites with increased dopant concentrations. IR and UV-Vis spectra suggest that the copper ions act as network modifiers, creating bond defects and free oxygen ions, and yielding a reduction of the optical bandgap energy at higher dopant contents. EPR data show that the shape of the resonance lines and the coordination geometry of the Cu²⁺ ions are influenced by the dopant concentrations. The analysis of the voltammetric data indicates that doping the recycled material with 20 mol% CuO and 10 mol% Sb₂O₃ eliminates the process of hydrogen evolution and reduces the anodic electrode passivation. Full article

Lead (Pb) poses a significant risk to human health and the environment. Global Pb production and consumption have markedly risen due to unregulated development and urbanization, Pb smelting, and Pb-acid battery processing. This study addresses the issue of elevated heavy metal concentrations in dust, soil, and groundwater in Shubra Al Khaymah due to the Awadallah Pb smelter. Pb concentration in soil and groundwater escalates in proximity to the Awadallah smelter and diminishes with distance from it—the surface soil functions as a repository for heavy metals. The concentrations of Pb (50–1500 µg/L), manganese (Mn) (1–750 µg/L), iron (Fe) (200–1250 µg/L), and boron (B) (250–1750 µg/L) in the groundwater stratum exceeded drinking and irrigation standards. A solution to the groundwater system issue is proposed by employing pumping wells adjacent to the riverbed to recover the contaminated water from the hydrogeological environment. Processing Modflow Path (PMPATH) program may delineate groundwater protection zones according to the travel time of 150 days (Zones 1 and 2) and the whole watershed source (Zone 3). An injection well was constructed to replenish excellent water quality in the groundwater aquifer in the upstream region. A 3D model of dissolved matter transport was created to examine the concentration distribution across remediation time in the contaminated region. This model demonstrates that, after 365 days of injection, the C/Co concentration ratio exceeded 70% in the downstream area, rendering it appropriate for drinking and irrigation. The alternate strategy is to encapsulate the severely contaminated zone. All measures aim to decrease the piezometric pressure in the vicinity, directing groundwater flow towards the contaminated zone, as accomplished by Processing Modflow Windows (PMWIN). Full article

A silver-rich lead alloy was obtained through the recycling of two metallurgical wastes: these are lead paste obtained from spent lead–acid batteries and a jarosite residue obtained from the hydrometallurgical production of zinc. Mixtures of both wastes were pyrometallurgically treated with sodium carbonate in a silicon carbide crucible at 1200 °C. The alloy and slag produced were analyzed by atomic absorption spectrometry, X-ray diffraction, and scanning electron microscopy with energy-dispersive spectra. High silver recovery was obtained in a Pb-Ag alloy for a mixture ratio of 30% Na₂CO₃–40% lead paste–30% jarosite, reaching a silver grade of 126 ppm. The slags produced for the highest jarosite content allow the compound formation of Na₂(SO₄) and Na₂Fe(SO₄)₂, which have high sulfur-fixing, avoiding SO₂ release and contributing to the minimization of atmospheric pollution. The novel pyrometallurgical route addresses not only the valorization of precious metals such as silver and lead but also the reduction in accumulated industrial waste. Full article

This paper presents a method for obtaining cobalt(II) perrhenate from waste derived from two types of materials, i.e., Li-ion battery scrap, or more precisely, battery mass, and superalloy scrap. Both of the above-mentioned materials are a source of Co. However, a source of rhenium is perrhenic acid produced from ammonium perrhenate (recycled) by the ion exchange method using resins. Co(OH)₂ can be precipitated from solutions resulting from the leaching of Li-ion battery mass, sludge from the Zn-Pb industry and superalloy scrap. The compound, after proper purification, can be used in a reaction with perrhenic acid to form Co(ReO₄)₂. The reaction should be conducted under the following conditions: time 1 h, room temperature, 30% excess of cobalt(II) hydroxide, and rhenium concentration in HReO₄ from about 20 g/dm³ to 300 g/dm³. This work shows that with the use of Co(OH)_2, obtained from waste, an anhydrous form of cobalt(II) perrhenate can be obtained, containing < 1000 ppm of the cumulative metal impurities. Full article

Lithium-ion portable batteries (LiPBs) contain valuable elements such as cobalt (Co), nickel (Ni), copper (Cu), lithium (Li) and manganese (Mn), which can be recovered through solid–liquid extraction using choline chloride-based Deep Eutectic Solvents (DESs) and bi-functional ionic liquids (ILs). This study was carried out to investigate the extraction of metals from solid powder, black mass (BM), obtained from LiPBs, with various solvents used: six choline chloride-based DESs in combination with organic acids: lactic acid (1:2, DES 1), malonic acid (1:1, DES 2), succinic acid (1:1, DES 3), glutaric acid (1:1, DES 4) and citric acid (1:1, DES 5 and 2:1, DES 6). Various additives, such as didecyldimethylammonium chloride (DDACl) surfactant, hydrogen peroxide (H₂O₂), trichloroisocyanuric acid (TCCA), sodium dichloroisocyanurate (NaDCC), pentapotassium bis(peroxymonosulphate) bis(sulphate) (PHM), (glycine + H₂O₂) or (glutaric acid + H₂O₂) were used. The best efficiency of metal extraction was obtained with the mixture of {DES 2 + 15 g of glycine + H₂O₂} in two-stage extraction at pH = 3, T = 333 K, 2 h. In order to obtain better extraction efficiency towards Co, Ni, Li and Mn (100%) and for Cu (75%), the addition of glycine was used. The obtained extraction results using choline chloride-based DESs were compared with those obtained with three bi-functional ILs: didecyldimethylammonium bis(2,4,4-trimethylpentyl) phosphinate, [N_10,10,1,1][Cyanex272], didecyldimethylammonium bis(2-ethylhexyl) phosphate, [N_10,10,1,1][D2EHPA], and trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, [P_6,6,6,14][Cyanex272]/toluene. The results of the extraction of all metal ions with these bi-functional ILs were only at the level of 35–50 wt%. The content of metal ions in aqueous and stripped organic solutions was determined by ICP-OES. In this work, we propose an alternative and highly efficient concept for the extraction of valuable metals from BM of LiPBs using DESs and ILs at low temperatures instead of acid leaching at high temperatures. Full article

In this study, we address the ecological challenges posed by automotive battery recycling, a process notorious for its environmental impact due to the buildup of hazardous waste like foundry slag. We propose a relatively cheap and safe solution for lead removal and recovery from samples of this type of slag. The analysis of TCLP extracts revealed non-compliance with international regulations, showing lead concentrations of up to 5.4% primarily in the form of anglesite (PbSO₄), as detected by XRF/XRD. We employed deep eutectic solvents (DES) as leaching agents known for their biodegradability and safety in hydrometallurgical processing. Five operational variables were systematically evaluated: sample type, solvent, concentration, temperature, and time. Using a solvent composed of choline chloride and glycerin in a 2:1 molar ratio, we achieved 95% lead dissolution from acidic samples at 90 °C, with agitation at 470 rpm, a pulp concentration of 5%, and a 5 h duration. Furthermore, we successfully recovered 55% of the lead in an optimized solution using an electrowinning cell. This research demonstrates the ability of DES to decontaminate slag, enabling compliance with regulations, the recovery of valuable metals, and new possibilities for the remaining material. Full article

Spent portable batteries belong to the category of hazardous waste, sometimes dumped together with non-hazardous municipal waste in landfills, resulting in various aquatic environments. Their presence in the aquatic environment leads to changes in its quality and its contamination with heavy metals or other toxic elements. This paper highlights the portable battery waste’s influence on the aquatic environment in stagnant conditions. Therefore, three types of batteries and three solutions with different pH values were used to represent the possible media existing in nature: acid (pH = 4.00), rainwater (pH = 5.63), and alkaline (pH = 8.00). After 180 days, the results showed changes in the chromatics and composition of the initial solutions. The analyses showed decreased pH, increased conductivity, and the transfer of several heavy metals into solutions (Cu, Pb, Zn, Ni, and Fe). Thus, there were slight exceedances of the maximum allowed values for water quality class I (Order no. 161/2006) in the case of Cu and Pb and higher exceedances in the case of Zn, Ni, and Fe. Zinc–carbon batteries stand out because of the release of Pb and Fe ions. The same applies to lithium manganese dioxide batteries because of Ni ions as well as zinc–manganese alloy batteries because of Cu and Zn ions. Altogether, the negative influence of spent batteries on the aquatic environment is noticed, and the measures for the implementation of safe disposal and processing are necessary. Full article

Spent lead–acid batteries have become the primary raw material for global lead production. In the current lead refining process, the tin oxidizes to slag, making its recovery problematic and expensive. This paper aims to present an innovative method for the fire refining of lead, which enables the retention of tin contained in lead from recycled lead–acid batteries. The proposed method uses aluminium scrap to remove impurities from the lead, virtually leaving all of the tin in it. The results of the conducted experiments indicate the high efficiency of the proposed method, which obtained a pure Pb-Sn alloy. This alloy is an ideal base material for the production of battery grids. This research was carried out on an industrial scale, which confirms the possibility of facile implementation of the method in almost every lead–acid battery recycling plant in the world. Full article

The active mass of the plates of aspent car battery with higher wear after an efficient desulfatization can be used as sources of a new electrode. This paper proposes the recycling of spent electrodes from a lead acid battery and the incorporation of NiO or Co₃O₄ contents by the melt-quenching method in order to enrich the electrochemical properties. The analysis of X-ray diffractograms indicates the gradual decrease in the sulfated crystalline phases, respectively, 4PbO·PbSO₄ and PbO·PbSO₄ phases, until their disappearance for higher dopant concentrations. Infrared (IR) spectra show a decreasing trend in the intensity of the bands corresponding to the sulfate ions and a conversion of [PbO₃] pyramidal units into [PbO₄] tetrahedral units by doping with high dopant levels, yielding to the apparition of the PbO₂ crystalline phase. The observed electron paramagnetic resonance (EPR) spectra confirm three signals located on the gyromagnetic factor, g~2, 2.2 and 8 assigned to the nickel ions in higher oxidation states as well as the metallic nickel nanoparticles. This compositional evolution can be explained by considering a process of the drastic reduction in nickel ions from the superior oxidation states to metallic nickel. The linewidth and the intensity of the resonance lines situated at about g~2, 2.17, 4.22 and 7.8 are attributed to the Co⁺² ions from the EPR data. The best reversibility of the cyclic voltammograms was highlighted for the samples with x = 10 mol% of NiO and 15 mol% of Co₃O₄, which are recommended as suitable in applications as new electrodes for the lead acid battery. Full article

Six test cells, two lead–acid batteries (LABs), and four lithium iron phosphate (LFP) batteries have been tested regarding their capacity at various temperatures (25 °C, 0 °C, and −18 °C) and regarding their cold crank capability at low temperatures (0 °C, −10 °C, −18 °C, and −30 °C). During the capacity test, the LFP batteries have a higher voltage level at all temperatures than LABs, which results in a higher power and energy output. Moreover, LFP batteries have a lower capacity decline and a lower energy decline for decreasing temperature. Regarding the cold-cranking test definition, the LABs passed the test at 0 °C, −10 °C, and −18 °C, but not at −30 °C. The LFP batteries passed the test at 0 °C and −10 °C. At −18 °C, only two of the four LFP batteries passed, while all LFP batteries failed the test at −30 °C. For comparability between technologies, it is suggested to redefine the requirements of the standard test in terms of power or energy. With this redefinition, the LFP battery can generate comparable cold-cranking results till −18 °C. Full article

NaH₂PO₄-MnO₂-PbO₂-Pb vitroceramics were studied usinginfrared (IR), ultraviolet-visible (UV-Vis) and electron paramagnetic resonance (EPR) spectroscopies to understand the structural modifications as potential candidates for electrode materials. The electrochemical performances of the NaH₂PO₄-MnO₂-PbO₂-Pb materials were investigated through measurements of cyclic voltammetry. Analysis of the results indicates that doping with a suitable content of MnO₂ and NaH₂PO₄ removes hydrogen evolution reactions and produces a partial desulphatization of the anodic and cathodic plates of the spent lead acid battery. Full article

The hydrometallurgical technology provides an efficient and sustainable green lead recovery process from lead acid batteries. Methanesulfonic acid has been widely considered as a green solvent for lead electrolytic recovery. However, the competitive precipitation of PbO₂ at anode and higher overpotential for OER limit the lead recovery efficiency. In this work, an anodic oxygen evolution reaction (OER) catalyst with a low Ir mass fraction of 7.2% is obtained by electroplating iridium on carbon cloth (CC), exhibiting a lower overpotential of 256 mV, longer lifetime of 10 h, and better stability in the 0.5 M MSA solution. When CC-Ir is used as an anodic catalyst for lead recovery in the lead methanesulfonate electrolyte, only a lesser Pb precipitation product with Pb atom mass fraction of 1.42% is found after electrolysis of 10 h, demonstrating the suppression effect of CC-Ir for a PbO₂ side reaction. This work proves that the anodic catalyst plays an important role in the lead electrolytic recovery process, which can inhibit the side reaction, reduce the energy consumption, and increase recovery efficiency. Full article

The development of functional materials from food waste sources and minerals is currently of high importance. In the present work, polylactic acid (PLA)/silica composites were prepared by in situ ring-opening polymerizations of L-lactide onto the surface of pristine (Silochrom) and amine-functionalized (Silochrom-NH₂) silica. The characteristics of the ring-opening polymerization onto the surface of modified and unmodified silica were identified and discussed. Fourier transform infrared spectroscopy was used to confirm the polymerization of lactide onto the silica surface, and thermogravimetric analysis determined that PLA constituted 5.9% and 7.5% of the composite mass for Silochrom/PLA and Silochrom-NH₂/PLA, respectively. The sorption properties of the composites with respect to Pb(II), Co(II), and Cu(II) ions were investigated, and the effect of contact time, initial metal ion concentration, and initial pH were evaluated. Silochrom-NH₂/PLA composites were found to have a higher adsorption capacity than Silochrom/PLA for all chosen ions, with the highest adsorption value occurring for Pb²⁺ at 1.5 mmol/g (90% removal efficiency). The composites showed the highest performance in the neutral or near-neutral pH (created by distilled water or buffer pH 6.86) during the first 15 min of phase contact. The equilibrium characteristics of adsorption were found to follow the Langmuir isotherm model rather than the Freundlich and Temkin models. Perspective applications for these PLA/silicas include remediation of industrial wastewater or leaching solutions from spent lead-acid and Li-ion batteries. Full article

Nanostructured Pb electrodes consisting of nanowire arrays were obtained by electrodeposition, to be used as negative electrodes for lead–acid batteries. Reduced graphene oxide was added to improve their performances. This was achieved via the electrochemical reduction of graphene oxide directly on the surface of nanowire arrays. The electrodes with and without reduced graphene oxide were tested in a 5 M sulfuric acid solution using a commercial pasted positive plate and an absorbed glass mat separator in a zero-gap configuration. The electrodes were tested in deep cycling conditions with a very low cut-off potential. Charge–discharge tests were performed at 5C. The electrode with reduced graphene oxide outperformed the electrode without reduced graphene oxide, as it was able to work with a very high utilization of active mass and efficiency. A specific capacity of 258 mAhg⁻¹–very close to the theoretical one–was achieved, and the electrode lasted for more than 1000 cycles. On the other hand, the electrode without reduced graphene oxide achieved a capacity close to 230 mAhg⁻¹, which corresponds to a 90% of utilization of active mass. Full article