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Li primary batteries are currently treated along with other Li batteries in several big pyro- metallurgical plants in Northern EU countries. Nevertheless, pyro-metallurgical processes do not allow for Mn and Li recycling and present negative environmental impacts, on the other hand hydrometallurgical processing can potentially ensure the integral recovery of all materials in Li primary batteries. In this work, preliminary experimental findings obtained in the LIFE-LIBAT project (LIFE16 ENV/IT/000389) are reported. In this project, end of life Li(0)-MnO2 batteries were cryo-mechanically treated and then the metals were recovered by a hydrometallurgical process. Representative samples of end of life Li(0) batteries were characterized by type and composition. Batteries were stabilized in an N2 bath and then crushed, sieved, and magnetically separated in the SEVal pilot units. Separated fractions (fine fraction, magnetic coarse fraction, and non-magnetic coarse fraction) were chemically characterized for target metal content (Li and Mn). Fractions were first treated for Li extraction and recovery, then the fine fraction was also leached for Mn recovery. Mass balances evidenced a 55% recycling rate and process simulations outlined profitability in the potentiality range in agreement with battery collection fluxes.

Experimental results of leaching tests using waste fractions obtained by mechanical pretreatment of lithium ion batteries (LIB) were reported. Two physical pretreatments were performed at pilot scale in order to recover electrodic powders: the first including crushing, milling, and sieving and the second granulation, and sieving. Recovery yield of electrodic powder was significantly influenced by the type of pretreatment. About 50% of initial LIB wastes was recovered by the first treatment (as electrodic powder with size0.5mm, Sample 1), while only 37% of powder with size1mm (Sample 2) can be recovered by the second treatment. Chemical digestion put in evidence the heterogeneity of recovered powders denoting different amounts of Co, Mn, and Ni. Leaching tests of both powders were performed in order to determine optimized conditions for metal extraction. Solid/liquid ratios and sulfuric acid concentrations were changed according to factorial designs at constant temperature (80°C). Optimized conditions for quantitative extraction (99%) of Co and Li from Sample 1 are 1/10g/mL as solid/liquid ratio and +50% stoichiometric excess of acid (1.1M). Using the same solid/liquid ratio, +100% acid excess (1.2M) is necessary to extract 96% of Co and 86% of Li from Sample 2. Best conditions for leaching of Sample 2 using glucose are +200% acid excess (1.7M) and 0.05M glucose concentration. Optimized conditions found in this work are among the most effective reported in the literature in term of Co extraction and reagent consumption.

Different kinds of panels (Si-based panels and CdTe panels) were treated according to a common process route made up of two main steps: a physical treatment (triple crushing and thermal treatment) and a chemical treatment. After triple crushing three fractions were obtained: an intermediate fraction (0.4–1 mm) of directly recoverable glass (17%w/w); a coarse fraction (>1 mm) requiring further thermal treatment in order to separate EVA-glued layers in glass fragments; a fine fraction (

End of life photovoltaic panels of different technologies (poly crystalline Si, amorphous Si, and CdTe) were treated mechanically in pilot scale by single shaft shredder minimizing the production of fine fractions below 0.4 mm (18% weight). Grounded material was sieved giving: an intermediate fraction (0.4-1 mm) of directly recoverable glass (18% weight); a coarse fraction (which should be further treated for encapsulant removal), and fine fractions of low-value glass (18%), which can be treated by leaching for the removal of metal impurities. Encapsulant removal from coarse fraction was successfully performed by solvent treatment using cyclohexane at 50 °C for 1 h giving high-grade glass (52% weight), which can be reused for panel production. Experimental results of solvent treatment were compared with those from thermal treatment by economic analysis and Life Cycle Assessment, denoting in both cases the advantages of solvent treatment in recovering high-value glass.

Co and Li recovery by acid-reducing leaching of lithium ion battery powder was investigated evidencing that glucose efficiency changes depending on leaching procedure. Postponing glucose addition metal extractive yields were higher (88% for Co and 92% for Li) than adding glucose at the beginning (60% for both). Chromatographic analyses evidenced that glucose degradation occurred preferentially via glucaric acid when its addition is postponed, while gluconic via is favored if glucose is added initially. Dynamic evolution of particle area showed particle fragmentation occurring during acid preleaching determining an increase of specific surface area available for further reaction when glucose is added.

In 2014, the European Union defined a list of 20 raw materials critical for economic importance and high supply risk. The aim of this work is to present the main results achieved within the EU-FP7 Project HydroWEEE-Demo dealing with the recovery of indium and cobalt, metals included in such European list, from LCD scraps and end of life Li-ion batteries, respectively. A complete indium recovery was achieved carrying out an acidic leaching, followed by a zinc cementation. Cobalt was extracted from the electrodic powder according to the following main operations: leaching (by acid reducing conditions), primary purification (by precipitation of metal impurities), solvent extraction with D2EPHA (for the removal of metal impurities), solvent extraction with Cyanex 272 (for the separation of cobalt from nickel), cobalt recovery (by precipitation as cobalt hydroxide). Co products with 95% purity were obtained by implementation of the solvent extraction with D2EHPA and Cyanex 272.

An innovative process was optimized to recover Co from portable Lithium Ion Batteries (LIB). Pilot scale physical pretreatment was performed to recover electrodic powder from LIB. Co was extracted from electrodic powder by a hydrometallurgical process including the following main stages: leaching (by acid reducing conditions), primary purification (by precipitation of metal impurities), solvent extraction with D2EPHA (for removal of metal impurities), solvent extraction with Cyanex 272 (for separation of cobalt from nickel), cobalt recovery (by precipitation of cobalt carbonate). Tests were separately performed to identify the optimal operating conditions for precipitation (pH 3.8 or 4.8), solvent extraction with D2EHPA (pH 3.8; Mn/D2EHPA = 4; 10% TBP; two sequential extractive steps) and solvent extraction with Cyanex 272 (pH 3.8; Cyanex/Cobalt = 4, 10% TBP, one extractive step). The sequence of optimized process stages was finally performed to obtain cobalt carbonate. Products with different degree of purity were obtained depending on the performed purification steps (precipitation with or without solvent extraction). 95% purity was achieved by implementation of the process including the solvent extraction stages with D2EHPA and Cyanex 272 and final washing for sodium removal.

In this paper the recycling of nickel metal hydride (NiMH), lithium ion (Li-ion) and primary lithium batteries was examined. Three mechanical routes of treatment were developed for each type recovering mainly three fractions: ferrous metals, non-ferrous metals and electrodic powders. The above mentioned types of spent batteries were also treated together by a unique mechanical route, obtaining in this way a powder enriched in cobalt, nickel and manganese which can be further extractable by chemical leaching. Experimental tests of solvent extraction were performed on synthetic leach liquors simulating a feed mixture of spent devices with weight composition 40% NiMH, 40% primary lithium, and 20% Li-ion (as determined by manual sorting of 3 tons of end of life batteries collected in Northern Italy). Under these conditions nickel and cobalt can be easily separated by using Cyanex 272 (stoichiometric ratio Cyanex/Co = 4, pH 5–6), but in presence of manganese Cyanex 272 loses its selectivity towards cobalt. Thus manganese must be preliminarily removed by using D2EHPA (stoichiometric ratio D2EHPA/Mn = 2, pH 4). Mechanical treatments and hydrometallurgical section to recover metals from electrodic powder are unavoidable operations in order to recover at least 50% of batteries as weight according to European Guideline 2006/66/EC.

Acid leaching of manganese from the powders of exhausted zinc alkaline batteries has been studied using carbohydrates as reducing agents. A mono-saccharide (glucose) and a di-saccharide (lactose) have been tested, the second as a template of industrial wastes. Manganese leaching was complete in the presence of both carbohydrates, along with zinc. Data from the factorial test with lactose have been analysed with ANOVA. The most significant effects for manganese extraction were sulphuric acid concentration, temperature, and lactose concentration.

Cobalt nanoparticles were synthesized by pulsed electrodeposition on copper substrate. Scanning electron microscopy and image analysis were used to determine morphology and particle size distribution of nanoparticle populations obtained in different operating conditions. After preliminary tests, ton and toff were set at 50 and 300 ms respectively to obtain distinct nanoparticles and avoid dendritic structures. Experimental tests were performed according to two partially superimposed factorial designs with two factors at two levels. First factorial design investigated the effect of current density (I = 10 and 50 mA/cm2) and discharged cobalt (Q = 2.5 × 10−3 and 1.0 × 10−2C); second factorial design investigated the effect of cobalt concentration (C0 = 0.01 and 0.1 M) for the same two levels of Q. For optimized value of ton/toff, square and hexagonal shaped nanoparticles were obtained. Statistical analysis evidenced that, for C0 = 0.1 mol/L, current density is the most influencing factor on mean size: increasing I from 10 to 50 mA/cm2 determined a diminution of mean size of 240 nm. For the same cobalt concentration, increasing the deposition time (Q) determined an increase of mean size of 60 nm. Diminishing the initial cobalt concentration from 0.1 to 0.01 mol/L determined an increase of mean size from 10 nm to 36 nm. For C0 = 0.01 mol/L nanoparticles grow reaching an optimal size (36 nm) and then, increasing the time of deposition, optimal sized subunits tend to aggregate. As for polydispersity of nanoparticles, statistical tests denoted that increasing I determined significant reduction of variance, while increasing the time of deposition determined a significant increase of variance.

Recycling of polycrystalline silicon, amorphous silicon and CdTe photovoltaic panels was investigated by studying two alternative routes made up of physical operations: two blade rotors crushing followed by thermal treatment and two blade rotors crushing followed by hammer crushing. Size distribution, X-ray diffraction and X-ray fluorescence analysis of obtained products were carried out in order to evaluate their properties as valuable products. Results showed that for all kinds of investigated photovoltaic modules the two blade rotors crushing followed by hammer crushing and eventually by a thermal treatment of d >1 mm fractions, was the best option aiming to a direct recovery of glass.

Photovoltaic (PV) technology for renewable energy utilisation is constantly growing throughout the world. Many recent efforts were devoted to the treatment of end-of-life panels, but only two full-scale processes were developed for crystalline silicon modules (Deutsche Solar) and CdTe panels (First Solar). Furthermore, recent developments concerned with new technologies designed for treating together more kinds of PV panels by automated processes. In this work, a picture of the PV world in terms of market, typology, waste dynamics and recoverable materials was given. A description of full-scale processes will be reported evidencing products and yields of recovery. A case study of process development for the simultaneous treatment of different kinds of PV panels was presented. In particular, experimental results in lab and pilot scale were described regarding the development and optimisation of a process including both physical pre-treatment and hydrometallurgical treatment for the recovery of target metal.

Manganese carbonate nanoparticles were produced by microemulsion method. The effects of different operating conditions on nanoparticles’ morphology, size, and polydispersity were determined. The reference system was made of cetyl trimethylammonium bromide, cyclohexane (as solvent), pentanol (as cosurfactant), and reactants MnCl2 and (NH4)2CO3. Investigated operating conditions were reaction time (30 and 60 min), solvent’s type (isooctane and hexane), cosurfactant’s dosage (3 and 4.5 g), and reactant’s concentration (1.0 and 0.25 mol/L). Produced nanoparticles were characterized by X-ray diffraction, scanning electron microscope, while particle size distribution was determined by image analysis. Significance of investigated factors was assessed by statistical analysis. Cubic–rhombohedral stacked particles with average size of 69 nm and standard deviations of 31 nm were obtained. Morphology was maintained in all the investigated conditions except when cosurfactant’s dosage was raised to 4.5 g. Statistical analysis showed that nanoparticles’ average size can be significantly increased with respect to the reference condition by augmenting reaction time (+49 nm), by increasing the cosurfactant’s dosage (+67 nm) and also by decreasing the reactant’s concentration when using hexane as solvent (+110 nm). Conversely, significant diminution of average size was obtained by using isooctane (−30 nm) and hexane (−26 nm) as solvents. Polydispersity of particle size distribution can be significantly diminished by using isooctane (8 nm) and hexane (13 nm) instead of cyclohexane, by decreasing reactant’s concentration in the reference condition (10 nm) and by raising cosurfactant’s dosage (12 nm).

In this paper two hydrometallurgical processes were analyzed for recovery of lithium and cobalt from lithium ion batteries. The effect of adding a secondary purification step by solvent extraction was evaluated in terms of product purity and economical feasibility of the process. Process routes were made of the following steps: mechanical pretreatment, leaching, primary (and secondary) purification, product recovery. Electrodic material used in leaching experiments was produced in a large scale pre-treatment plant for waste recycling. Leaching tests were performed both using chloridric acid and sulphuric acid plus glucose. In optimized conditions quantitative extraction of Co and Li were obtained for both tested systems. Iron, aluminum and copper were removed by precipitation as hydroxides, while Ni can be separated only using solvent extraction. Process simulations showed that, for the same input flow rate of batteries, the addition of solvent extraction improves the economical feasibility of the process for lithium ion battery recovery.

The aim of this work was developing a hydrometallurgical process to recover metals from automobile shredded residue (or car fluff). Automobile shredded residue (ASR) was characterised by particle size distribution, total metal content and metal speciation in order to guide the choice of target metals and the operating conditions of leaching. Characterisation results showed that Fe is the most abundant metal in the waste, while Zn was the second abundant metal in the fraction with diameter lower than 500 μm. Sequential extractions denoted that Zn was easily extractable by weak acid attack, while Fe and Al required a strong acid attack to be removed. In order to recover zinc from

In this paper heavy metal pollution at an abandoned Italian pyrite mine has been investigated by comparing total concentrations and speciation of heavy metals (Fe, Cu, Mn, Zn, Pb and As) in a red mud sample and a river sediment. Acid digestions show that all the investigated heavy metals present larger concentrations in the sediment than in the tailing. A modified Tessier's procedure has been used to discriminate heavy metal bound to organic fraction from those originally present in the mineral sulphide matrix and to detect a possible trend of metal mobilisation from red mud to river sediment. Sequential extractions on bulk and size fractionated samples denote that sediment samples present larger percent concentrations of the investigated heavy metals in the first extractive steps (I-IV) especially in lower dimension size fractionated samples suggesting that heavy metals in the sediment are significantly bound by superficial adsorption mechanisms.