28 research outputs found
Recommended from our members
Bias and size effects of price-comparison platforms: theory and experimental evidence
We analyze the impact on consumer prices of some information characteristics of price comparison search platforms. An equilibrium model where vendors compete in prices and consumers do not observe prices, but can obtain price information through a search platform, is developed. The model generates several predictions about the impact on the price distribution of: (i) the size of the search platformâs sample, (ii) whether the search
platformâs sample is random, and (iii) the number of vendors in the market. The modelâs predictions are tested experimentally. The results confirm the predictions about (ii) and (iii), but reject the modelâs predictions about (i)
New Perspectives for Electrodialytic Remediation
Electrodialytic remediation has been widely used for the recovery of different contaminants from numerous matrices, such as, for example, polluted soils, wastewater sludge, fly ash, mine tailing or harbour sediments. The electrodialytic remediation is an enhancement of the electrokinetic remediation technique, and it consists of the use of ion-exchange membranes for the control of the acid and the alkaline fronts generated in the electrochemical processes. While the standard electrodialytic cell is usually built with three-compartment configuration, it has been shown that for the remediation of matrices that require acid environment, a two-compartment cell has given satisfactory removal efficiencies with reduced energy costs.
Recycling secondary batteries, with growing demand, has an increasing economic and environmental interest. This work focusses on the proposal of the electrodialytic remediation technique as a possible application for the recycling of lithium-ion cells and other secondary batteries. The recovery of valuable components, such as lithium, manganese, cobalt of phosphorous, based on current recycling processes and the characterization of solid waste is addressed.This work has received funding from the European Unionâs Horizon 2020 research and innovation programme under the Marie SkĆodowska-Curie grant agreement No. 778045. Paz-Garcia acknowledges the financial support from the University of Malaga, project: PPIT.UMA.B5.2018/17. Villen-Guzman acknowledges the funding from the University of Malaga for the postdoctoral fellowship PPIT.UMA.A.3.2.2018.
Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tec
Electrodialytic Recovery of Cobalt from Spent Lithium-Ion Batteries
ContribuciĂłn en congreso cientĂficoRecycling lithium-ion batteries has an increasing interest for economic and environmental reasons. Disposal of lithium-ion batteries imposes high risk to the environment due to the toxicity of some of their essential components. In addition to this, some of these components, such as cobalt, natural graphite and phosphorus, are included in the list of critical raw materials for the European Union due to their strategic importance in the manufacturing industry. Therefore, in the recent years, numerous research studies have been focused on the development of efficient processes for battery recycling and the selective recuperation of these key components.
LiCoO2 is the most common material use in current lithium-ion batteries cathodes. In the current work, an electrodialytic method is proposed for the recovery of cobalt from this kind of electrode. In a standard electrodialytic cell, the treated matrix is separated from the anode and the cathode compartments by means of ion-exchange membranes. A cation-exchange membrane (CEM) allows the passage of cations and hinders the passage of anions, while the behaviour of anion-exchange membrane (AEM) does the opposite. A three-compartment electrodialytic cell has been designed and assembled, as depicted in the figure. In the central compartment, a suspension of LiCoO2 is added.
Different extracting agents, such as EDTA, HCl and HNO3, are tested to enhanced the dissolution and the selective extraction of the target metal. Dissolved cobalt-containing complexes migrate towards the cathode or the anode compartments depending on the ionic charge of the complexes. While cobalt extraction via extracting agents is an expensive treatment, as it requires the constant addition of chemicals, an efficient electrodialytic cell could allow the recirculation of the extracting agents and the economical optimization of the process.This work has received funding from the European Unionâs Horizon 2020 research and innovation programme under the Marie SkĆodowska-Curie grant agreement No. 778045. Paz-Garcia acknowledges the financial support from the University of Malaga, project: PPIT.UMA.B5.2018/17. Villen-Guzman acknowledges the funding from the University of Malaga for the postdoctoral fellowship PPIT.UMA.A.3.2.2018.
Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tec
Nature and evolution of Pd catalysts supported on activated carbon fibers during the catalytic reduction of bromate in water
[EN] Catalytic hydrogenation of bromate using Pd catalysts supported on activated carbon fibers is a smart solution to treat bromate polluted water. These catalysts have been analyzed by different techniques for an in-deep characterization of the active sites. The in situ X-ray absorption spectroscopy and the CO chemisorption studies showed that Pd-0 nanoparticles with different crystal sizes were generated on the support during hydrogen activation at 200 degrees C and that the PdHx-phase was formed during the cooling to room temperature. As PdHx species formed on Pd-0 nanoparticles are responsible for bromate reduction, the most active catalysts are those having Pd-0 nanoparticles with large crystal sizes, where PdHx species are easily formed. The catalysts are fully stable in succesive reaction runs. It has been also shown that bromate reduction rate depends on the bromate concentration and on the hydrogen partial pressure, with a pseudo-first reaction order towards both reactants.Authors thank the Spanish Ministry of Economy and Competitiveness through RTI2018-101784-B-I00 (MINECO/FEDER) and SEV-2016-0683 projects for the financial support. We gratefully acknowledge ALBA synchrotron for allocating beamtime (proposal 2015091414) and CLAESS beamline staff for their technical support during our experiment. C. W. Lopes (Science without Frontiers -Process no. 13191/13-6) thanks CAPES for a predoctoral fellowship. J. L. Cerrillo is grateful to MINECO for the Severo Ochoa contract for PhD formation (SVP-2014-068600). L. Kiwi-Minsker acknowledges financial support provided by Russian Science Foundation (project 15-19-20023). Authors also thank Kynol Europa GmbH for the supply of the activated carbon fibers.Cerrillo, JL.; Lopes, CW.; Rey Garcia, F.; Agostini, G.; Kiwi-Minsker, L.; Palomares Gimeno, AE. (2020). Nature and evolution of Pd catalysts supported on activated carbon fibers during the catalytic reduction of bromate in water. Catalysis Science & Technology. 10(11):3646-3653. https://doi.org/10.1039/d0cy00606hS364636531011Naushad, M., Khan, M. R., ALOthman, Z. A., AlSohaimi, I., Rodriguez-Reinoso, F., Turki, T. M., & Ali, R. (2015). Removal of BrO3 â from drinking water samples using newly developed agricultural waste-based activated carbon and its determination by ultra-performance liquid chromatography-mass spectrometry. Environmental Science and Pollution Research, 22(20), 15853-15865. doi:10.1007/s11356-015-4786-yBUTLER, R., GODLEY, A., LYTTON, L., & CARTMELL, E. (2005). Bromate Environmental Contamination: Review of Impact and Possible Treatment. Critical Reviews in Environmental Science and Technology, 35(3), 193-217. doi:10.1080/10643380590917888Weinberg, H. S., Delcomyn, C. A., & Unnam, V. (2003). Bromate in Chlorinated Drinking Waters:â Occurrence and Implications for Future Regulation. Environmental Science & Technology, 37(14), 3104-3110. doi:10.1021/es026400zOMS , Bromate in Drinking-water - Guidelines for Drinking-water Quality , WHO , 2005JabĆoĆska, M., KrĂłl, A., Kukulska-ZajÄ
c, E., Tarach, K., Girman, V., Chmielarz, L., & GĂłra-Marek, K. (2015). Zeolites Y modified with palladium as effective catalysts for low-temperature methanol incineration. Applied Catalysis B: Environmental, 166-167, 353-365. doi:10.1016/j.apcatb.2014.11.047Pergher, S. B. ., Dallago, R. M., Veses, R. C., Gigola, C. E., & Baibich, I. M. (2004). Pd/NaY-zeolite and Pd-W/NaY-zeolite catalysts: preparation, characterization and NO decomposition activity. Journal of Molecular Catalysis A: Chemical, 209(1-2), 107-115. doi:10.1016/j.molcata.2003.08.005Chaplin, B. P., Reinhard, M., Schneider, W. F., SchĂŒth, C., Shapley, J. R., Strathmann, T. J., & Werth, C. J. (2012). Critical Review of Pd-Based Catalytic Treatment of Priority Contaminants in Water. Environmental Science & Technology, 46(7), 3655-3670. doi:10.1021/es204087qHöller, V., RĂ„devik, K., Yuranov, I., Kiwi-Minsker, L., & Renken, A. (2001). Reduction of nitrite-ions in water over Pd-supported on structured fibrous materials. Applied Catalysis B: Environmental, 32(3), 143-150. doi:10.1016/s0926-3373(01)00139-4Shen, W.-J., Ichihashi, Y., Ando, H., Okumura, M., Haruta, M., & Matsumura, Y. (2001). Influence of palladium precursors on methanol synthesis from CO hydrogenation over Pd/CeO2 catalysts prepared by depositionâprecipitation method. Applied Catalysis A: General, 217(1-2), 165-172. doi:10.1016/s0926-860x(01)00606-8Hirayama, J., & Kamiya, Y. (2018). Tin-palladium supported on alumina as a highly active and selective catalyst for hydrogenation of nitrate in actual groundwater polluted with nitrate. Catalysis Science & Technology, 8(19), 4985-4993. doi:10.1039/c8cy00730fPalomares, A. E., Franch, C., Yuranova, T., Kiwi-Minsker, L., GarcĂa-Bordeje, E., & Derrouiche, S. (2014). The use of Pd catalysts on carbon-based structured materials for the catalytic hydrogenation of bromates in different types of water. Applied Catalysis B: Environmental, 146, 186-191. doi:10.1016/j.apcatb.2013.02.056Chen, H., Xu, Z., Wan, H., Zheng, J., Yin, D., & Zheng, S. (2010). Aqueous bromate reduction by catalytic hydrogenation over Pd/Al2O3 catalysts. Applied Catalysis B: Environmental, 96(3-4), 307-313. doi:10.1016/j.apcatb.2010.02.021Soares, O. S. G. P., Freitas, C. M. A. S., Fonseca, A. M., ĂrfĂŁo, J. J. M., Pereira, M. F. R., & Neves, I. C. (2016). Bromate reduction in water promoted by metal catalysts prepared over faujasite zeolite. Chemical Engineering Journal, 291, 199-205. doi:10.1016/j.cej.2016.01.093Freitas, C. M. A. S., Soares, O. S. G. P., ĂrfĂŁo, J. J. M., Fonseca, A. M., Pereira, M. F. R., & Neves, I. C. (2015). Highly efficient reduction of bromate to bromide over mono and bimetallic ZSM5 catalysts. Green Chemistry, 17(8), 4247-4254. doi:10.1039/c5gc00777aRestivo, J., Soares, O. S. G. P., ĂrfĂŁo, J. J. M., & Pereira, M. F. R. (2015). Bimetallic activated carbon supported catalysts for the hydrogen reduction of bromate in water. Catalysis Today, 249, 213-219. doi:10.1016/j.cattod.2014.10.048Restivo, J., Soares, O. S. G. P., ĂrfĂŁo, J. J. M., & Pereira, M. F. R. (2017). Catalytic reduction of bromate over monometallic catalysts on different powder and structured supports. Chemical Engineering Journal, 309, 197-205. doi:10.1016/j.cej.2016.10.025Soares, O. S. G. P., Ramalho, P. S. F., Fernandes, A., ĂrfĂŁo, J. J. M., & Pereira, M. F. R. (2019). Catalytic bromate reduction in water: Influence of carbon support. Journal of Environmental Chemical Engineering, 7(3), 103015. doi:10.1016/j.jece.2019.103015Perez-Coronado, A. M., Soares, O. S. G. P., Calvo, L., Rodriguez, J. J., Gilarranz, M. A., & Pereira, M. F. R. (2018). Catalytic reduction of bromate over catalysts based on Pd nanoparticles synthesized via water-in-oil microemulsion. Applied Catalysis B: Environmental, 237, 206-213. doi:10.1016/j.apcatb.2018.05.077Li, M., Zhou, X., Sun, J., Fu, H., Qu, X., Xu, Z., & Zheng, S. (2019). Highly effective bromate reduction by liquid phase catalytic hydrogenation over Pd catalysts supported on core-shell structured magnetites: Impact of shell properties. Science of The Total Environment, 663, 673-685. doi:10.1016/j.scitotenv.2019.01.392Chen, X., Huo, X., Liu, J., Wang, Y., Werth, C. J., & Strathmann, T. J. (2017). Exploring beyond palladium: Catalytic reduction of aqueous oxyanion pollutants with alternative platinum group metals and new mechanistic implications. Chemical Engineering Journal, 313, 745-752. doi:10.1016/j.cej.2016.12.058Gao, Y., Sun, W., Yang, W., & Li, Q. (2017). Creation of Pd/Al2O3 Catalyst by a Spray Process for Fixed Bed Reactors and Its Effective Removal of Aqueous Bromate. Scientific Reports, 7(1). doi:10.1038/srep41797Li, M., Hu, Y., Fu, H., Qu, X., Xu, Z., & Zheng, S. (2019). Pt embedded in carbon rods of N-doped CMK-3 as a highly active and stable catalyst for catalytic hydrogenation reduction of bromate. Chemical Communications, 55(78), 11786-11789. doi:10.1039/c9cc05274gMarco, Y., GarcĂa-BordejĂ©, E., Franch, C., Palomares, A. E., Yuranova, T., & Kiwi-Minsker, L. (2013). Bromate catalytic reduction in continuous mode using metal catalysts supported on monoliths coated with carbon nanofibers. Chemical Engineering Journal, 230, 605-611. doi:10.1016/j.cej.2013.06.040Yuranova, T., Kiwi-Minsker, L., Franch, C., Palomares, A. E., Armenise, S., & GarcĂa-BordejĂ©, E. (2013). Nanostructured Catalysts for the Continuous Reduction of Nitrates and Bromates in Water. Industrial & Engineering Chemistry Research, 52(39), 13930-13937. doi:10.1021/ie302977hPalomares, A. E., Franch, C., & Corma, A. (2011). A study of different supports for the catalytic reduction of nitrates from natural water with a continuous reactor. Catalysis Today, 172(1), 90-94. doi:10.1016/j.cattod.2011.05.015Yuranova, T., Franch, C., Palomares, A. E., Garcia-BordejĂ©, E., & Kiwi-Minsker, L. (2012). Structured fibrous carbon-based catalysts for continuous nitrate removal from natural water. Applied Catalysis B: Environmental, 123-124, 221-228. doi:10.1016/j.apcatb.2012.04.007Lan, H., Mao, R., Tong, Y., Liu, Y., Liu, H., An, X., & Liu, R. (2016). Enhanced Electroreductive Removal of Bromate by a Supported PdâIn Bimetallic Catalyst: Kinetics and Mechanism Investigation. Environmental Science & Technology, 50(21), 11872-11878. doi:10.1021/acs.est.6b02822Yao, F., Yang, Q., Yan, M., Li, X., Chen, F., Zhong, Y., ⊠Li, X. (2020). Synergistic adsorption and electrocatalytic reduction of bromate by Pd/N-doped loofah sponge-derived biochar electrode. Journal of Hazardous Materials, 386, 121651. doi:10.1016/j.jhazmat.2019.121651Morais, D. F. S., Boaventura, R. A. R., Moreira, F. C., & Vilar, V. J. P. (2019). Advances in bromate reduction by heterogeneous photocatalysis: The use of a static mixer as photocatalyst support. Applied Catalysis B: Environmental, 249, 322-332. doi:10.1016/j.apcatb.2019.02.070Cunha, G. S., Santos, S. G. S., Souza-Chaves, B. M., Silva, T. F. C. V., Bassin, J. P., Dezotti, M. W. C., ⊠Vilar, V. J. P. (2019). Removal of bromate from drinking water using a heterogeneous photocatalytic mili-reactor: impact of the reactor material and water matrix. Environmental Science and Pollution Research, 26(32), 33281-33293. doi:10.1007/s11356-019-06266-9Matatov-Meytal, Y., & Sheintuch, M. (2002). Catalytic fibers and cloths. Applied Catalysis A: General, 231(1-2), 1-16. doi:10.1016/s0926-860x(01)00963-2Joannet, E., Horny, C., Kiwi-Minsker, L., & Renken, A. (2002). Palladium supported on filamentous active carbon as effective catalyst for liquid-phase hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol. Chemical Engineering Science, 57(16), 3453-3460. doi:10.1016/s0009-2509(02)00215-4Crespo-Quesada, M., Dykeman, R. R., Laurenczy, G., Dyson, P. J., & Kiwi-Minsker, L. (2011). Supported nitrogen-modified Pd nanoparticles for the selective hydrogenation of 1-hexyne. Journal of Catalysis, 279(1), 66-74. doi:10.1016/j.jcat.2011.01.003Fang, W., Yang, S., Wang, X.-L., Yuan, T.-Q., & Sun, R.-C. (2017). Manufacture and application of lignin-based carbon fibers (LCFs) and lignin-based carbon nanofibers (LCNFs). Green Chemistry, 19(8), 1794-1827. doi:10.1039/c6gc03206kYaseneva, P., Marti, C. F., Palomares, E., Fan, X., Morgan, T., Perez, P. S., ⊠Lapkin, A. A. (2014). Efficient reduction of bromates using carbon nanofibre supported catalysts: Experimental and a comparative life cycle assessment study. Chemical Engineering Journal, 248, 230-241. doi:10.1016/j.cej.2014.03.034Shim, J.-W., Park, S.-J., & Ryu, S.-K. (2001). Effect of modification with HNO3 and NaOH on metal adsorption by pitch-based activated carbon fibers. Carbon, 39(11), 1635-1642. doi:10.1016/s0008-6223(00)00290-6Rouquerol, J., Llewellyn, P., & Rouquerol, F. (2007). Is the bet equation applicable to microporous adsorbents? Characterization of Porous Solids VII - Proceedings of the 7th International Symposium on the Characterization of Porous Solids (COPS-VII), Aix-en-Provence, France, 26-28 May 2005, 49-56. doi:10.1016/s0167-2991(07)80008-5J. R. Anderson , Structure of metallic catalysts , Academic Press , London-New York , 1918MartĂnez, A., Arribas, M. A., Derewinski, M., & Burkat-Dulak, A. (2010). Enhanced sulfur resistance of bifunctional Pd/HZSM-5 catalyst comprising hierarchical carbon-templated zeolite. Applied Catalysis A: General, 379(1-2), 188-197. doi:10.1016/j.apcata.2010.03.023Ravel, B., & Newville, M. (2005). ATHENA,ARTEMIS,HEPHAESTUS: data analysis for X-ray absorption spectroscopy usingIFEFFIT. Journal of Synchrotron Radiation, 12(4), 537-541. doi:10.1107/s0909049505012719Groppo, E., Agostini, G., Borfecchia, E., Wei, L., Giannici, F., Portale, G., ⊠Lamberti, C. (2014). Formation and Growth of Pd Nanoparticles Inside a Highly Cross-Linked Polystyrene Support: Role of the Reducing Agent. The Journal of Physical Chemistry C, 118(16), 8406-8415. doi:10.1021/jp5003897Groppo, E., Liu, W., Zavorotynska, O., Agostini, G., Spoto, G., Bordiga, S., ⊠Zecchina, A. (2010). Subnanometric Pd Particles Stabilized Inside Highly Cross-Linked Polymeric Supports. Chemistry of Materials, 22(7), 2297-2308. doi:10.1021/cm903176dBugaev, A. L., Guda, A. A., Lazzarini, A., Lomachenko, K. A., Groppo, E., Pellegrini, R., ⊠Lamberti, C. (2017). In situ formation of hydrides and carbides in palladium catalyst: When XANES is better than EXAFS and XRD. Catalysis Today, 283, 119-126. doi:10.1016/j.cattod.2016.02.065FernĂĄndez-GarcĂa, M. (2002). XANES analysis of catalytic systems under reaction conditions. Catalysis Reviews, 44(1), 59-121. doi:10.1081/cr-120001459Lopes, C. W., Cerrillo, J. L., Palomares, A. E., Rey, F., & Agostini, G. (2018). An in situ XAS study of the activation of precursor-dependent Pd nanoparticles. Physical Chemistry Chemical Physics, 20(18), 12700-12709. doi:10.1039/c8cp00517fWang, J., Wang, Q., Jiang, X., Liu, Z., Yang, W., & Frenkel, A. I. (2014). Determination of Nanoparticle Size by Measuring the MetalâMetal Bond Length: The Case of Palladium Hydride. The Journal of Physical Chemistry C, 119(1), 854-861. doi:10.1021/jp510730aSrabionyan, V. V., Bugaev, A. L., Pryadchenko, V. V., Avakyan, L. A., van Bokhoven, J. A., & Bugaev, L. A. (2014). EXAFS study of size dependence of atomic structure in palladium nanoparticles. Journal of Physics and Chemistry of Solids, 75(4), 470-476. doi:10.1016/j.jpcs.2013.12.012Franch, C., RodrĂguez-CastellĂłn, E., Reyes-Carmona, Ă., & Palomares, A. E. (2012). Characterization of (Sn and Cu)/Pd catalysts for the nitrate reduction in natural water. Applied Catalysis A: General, 425-426, 145-152. doi:10.1016/j.apcata.2012.03.015Dong, Z., Dong, W., Sun, F., Zhu, R., & Ouyang, F. (2012). Effects of preparation conditions on catalytic activity of Ru/AC catalyst to reduce bromate ion in water. Reaction Kinetics, Mechanisms and Catalysis, 107(1), 231-244. doi:10.1007/s11144-012-0473-xRestivo, J., Soares, O. S. G. P., ĂrfĂŁo, J. J. M., & Pereira, M. F. R. (2015). Metal assessment for the catalytic reduction of bromate in water under hydrogen. Chemical Engineering Journal, 263, 119-126. doi:10.1016/j.cej.2014.11.052Siddiqui, M., Zhai, W., Amy, G., & Mysore, C. (1996). Bromate ion removal by activated carbon. Water Research, 30(7), 1651-1660. doi:10.1016/0043-1354(96)00070-xSun, J., Zhang, J., Fu, H., Wan, H., Wan, Y., Qu, X., ⊠Zheng, S. (2018). Enhanced catalytic hydrogenation reduction of bromate on Pd catalyst supported on CeO2 modified SBA-15 prepared by strong electrostatic adsorption. Applied Catalysis B: Environmental, 229, 32-40. doi:10.1016/j.apcatb.2018.02.009Sun, W., Li, Q., Gao, S., & Shang, J. K. (2013). Highly efficient catalytic reduction of bromate in water over a quasi-monodisperse, superparamagnetic Pd/Fe3O4 catalyst. Journal of Materials Chemistry A, 1(32), 9215. doi:10.1039/c3ta11455
Acid leaching of LiCoO2 enhanced by reducing agent. Model formulation and validation.
In this work, a model has been formulated to describe the complex process of LiCoO2 leaching through the participation of competing reactions in acid media including the effect of H2O2 as reducing agent. The model presented here describes the extraction of Li and Co in the presence and absence of H2O2, and it takes into account the different phenomena affecting the controlling mechanisms. In this context, the model predicts the swift from kinetic control to diffusion control. The model has been implemented and solved to simulate the leaching process. To validate the model and to estimate the model parameters, a set of 12 (in triplicate) extraction experiments were carried out varying the concentration of hydrochloric acid (within the range of 0.5â2.5 M) and hydrogen peroxide (range 0â0.6%v/v). The simulation results match fairly well with the experimental data for a wide range of conditions. Furthermore, the model can be used to predict results with different solid-liquid ratios as well as different acid and oxygen peroxide concentrations. This model could be used to design or optimize a LiCoO2 extraction process facilitating the corresponding economical balance of the treatment.This work has received funding from the European Unionâs Horizon 2020 research and innovation programme under the Marie SkĆodowska- Curie grant agreement No. 778045 and the âProyectos I+D+i en el marco del Programa Operativo FEDER AndalucĂa 2014â2020â, Project no. UMA18-FEDERJA-279. Cerrillo-Gonzalez acknowledges the FPU grant (FPU18/04295) obtained from the Spanish Ministry of Education. Funding for open access charge: Universidad de MĂĄlaga / CBUA
Alternative reducing agents for Lithium-Ion batteries recycling via hydrometallurgical process
Lithium-ion batteries (LIB) are a key factor in the transition to a decarbonised and clean energy system due to their application in the power sector and electric transport. However, a growing demand of these batteries involves two direct problems: an increase in the generation of spent LIBs as well as in the demand of raw materials. Hence, the development of efficient recycling treatment of LIBs is crucial to make them a true enabler of the green transition.
Currently, the LIBs recycling process can be divided into pyrometallurgical and hydrometallurgical. The first one is based on the treatment of LIBs at high temperatures to produces metal pyrolysis and metal reduction, while the second method consists in the recovery of metals via acidic leaching. Although pyrometallurgical method is the most used in the industry, hydrometallurgical process presents a series of advantages, such as low energy consumption, high metal recovery and high product purity, that make it more promising in the search of more effective recycling method. In the hydrometallurgical process, the addition of acids and reducing agents is required to dissolve the solid particles and extract the valuable metals.
The purpose of this work was to evaluate the effect of alternative reducing agent in the leaching process to maximize the amount of metal (Mn, Li, Ni, Co) recovered from a real LIBs waste. With this aim, the leaching processes were carried out using as reducing agent H2O2, Fe and NH4Cl. According to the experimental results, Fe and NH4Cl enhance the extraction yield as well as the reaction time comparing with the results obtain using H2O2.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech
Hydrometallurgical extraction of Li and Co from LiCoO2 particlesâExperimental and Modeling
The use of lithium-ion batteries as energy storage in portable electronics and electric vehicles is increasing rapidly, which involves the consequent increase of battery waste. Hence, the development of reusing and recycling techniques is important to minimize the environmental impact of these residues and favor the circular economy goal. This paper presents experimental and modeling results for the hydrometallurgical treatment for recycling LiCoO2 cathodes from lithium-ion batteries. Previous experimental results for hydrometallurgical extraction showed that acidic leaching of LiCoO2 particles produced a non-stoichiometric extraction of lithium and cobalt. Furthermore, the maximum lithium extraction obtained experimentally seemed to be limited, reaching values of approximately 65â70%. In this paper, a physicochemical model is presented aiming to increase the understanding of the leaching process and the aforementioned limitations. The model describes the heterogeneous solidâliquid extraction mechanism and kinetics of LiCoO2 particles under a weakly reducing environment. The model presented here sets the basis for a more general theoretical framework that would describe the process under different acidic and reducing conditions. The model is validated with two sets of experiments at different conditions of acid concentration (0.1 and 2.5 M HCl) and solid to liquid ratio (5 and 50 g Lâ1). The COMSOL Multiphysics program was used to adjust the parameters in the kinetic model with the experimental results.This work has received funding from the European Unionâs Horizon 2020 research and innovation programme under the Marie SkĆodowska-Curie grant agreement No. 778045. Paz-Garcia acknowledges financial support from the program âProyectos I+D+i en el marco del Programa Operativo FEDER AndalucĂa 2014â2020â, No. UMA18-FEDERJA-279. Cerrillo-Gonzalez acknowledges the FPU grant obtained from the Spanish Ministry of Education. The University of Malaga is acknowledged for the financial support in the postdoctoral fellowship of Villen-Guzman
Leaching of LiCoO2 using H2O2 as reductant
The growing use of Lithium-Ion batteries (LIBs) in the field of electric vehicles and renewable energy storage entails the production of toxic and environmental hazardous wastes. Furthermore, some components in these batteries are classified as Critical Raw Material due to their supply risk and economic importance. Hence, the development of more efficient process to recycle LIBs is gaining importance for economic aspects and environmental protection.
In this work, the hydrometallurgical leaching process for the recovery of valuable metals from the cathode active materials of spent LIBs batteries was evaluated. Batch Experiments were carried out using LiCoO2 which is one of the most used cathodes in lithium-ion batteries. The selection of the extracting agent, its concentration, the reducing agent and the solid-liquid ratio are some of the parameters under study in this research.
Hydrochloric acid was used as the extracting agent and its concentration was modified from 0.1 M to 2.5 M while solid-liquid ratio (50 g/L), temperature (25 ÂșC) were fixed in all of them. The percentage of metal extracted was 31% of Co and 66% of Li for 0.1 M HCl solution. Extraction with 2.5M HCl solution was similar, 35% and 71% of Co and Li, respectively, but extracted in just 90 min, unlike the 72 h in the previous test. An experiment using H2O2 as a reducing agent was also performed, reaching a high percentage of metal extracted: 93% of Co and 100% of Li for a 0.6%vol of H2O2
Although tests have been carried out using LiCoO2, the technique can be applied to different kinds of cathode from spent batteries. The results suggested that the recovery of Co and Li is viable at optimized experimental conditions. The results indicated clearly that the dissolution of LiCoO2 particles is faster and more extensive when using more acidic extracting solution and stronger reducing agents, such as hydrogen peroxide.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech
Modeling of LiCoO2 leaching reaction using COMSOL multiphysics
Currently, the most popular LIBs recycling processes are either pyrometallurgical and hydrometallurgical. Although the former is the most used method on an industrial scale, hydrometallurgical has become a promising process due to its recovery rate, high purity of the metals and a lower energy consumption. The main step of the hydrometallurgical process is the leaching, where acid is used as an extracting agent to recover metal from the waste LIBs. Different factors influencing the leaching process are the extracting agent concentration, temperature, solid-liquid ratio, reaction time and reductant agent concentration. Determine the reaction rate and the rate controlling step is essential to optimize leaching parameters and improve the process efficiency.
In this work, a mathematical model is presented with the aim of determine the leaching reaction kinetic of LIBs components, namely, LiCoO2 particles. The model is based on a solid-liquid reaction model, in particular on the shrinking core model, due to the formation of Co3O4 in the outer part of the LiCoO2 particle when is used an inorganic acid as extracting agent in absence of an external reducing agent. In this model, the diffusion of the reactant through the product layer and the chemical reaction at the surface of the unreacted core are defined as the rate controlling step. A series of extraction analyses were carried out and their results were used to adjust the formulated model.
COMSOL Multiphysics 5.5 program was used to adjust the kinetic model with the experimental results, obtaining as result the value of the kinetics and diffusion constant. The implemented model for simulation of the lithium and cobalt leaching from LiCoO2 reproduces the experimental results, predicting the non-equimolar proportion between Li+ and Co2+ and verifying the hypothesis of the Co3O4 layer formation.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech
Recovery of Li and Co from LiCoO2 via HydrometallurgicalâElectrodialytic Treatment
Lithium-ion batteries play an important role in our modern society as the main option to power portable electronic devices and electric vehicles. The growing demand for these batteries encourages the development of more efficient recycling processes, aiming to decrease the environmental impact of the spent batteries and recover their valuable components. In this paper, a combined hydrometallurgical-electrodialytic method is proposed for processing battery waste. In the combined technique, the amount of leaching solution is reduced as acid is generated via electrolysis. At the same time, the use of ion-exchange membranes and the possibility of electroplating allows for a selective separation of the target metals. Experiments were performed using LiCoO2, which is one of the most used cathodes in lithium-ion batteries. First, 0.1 M HCl solution was used in batch extractions to study the kinetics of LiCoO2 dissolution, reaching an extraction of 30% and 69% of cobalt and lithium, respectively. Secondly, hydrometallurgical extraction experiments were carried out in three-compartment electrodialytic cells, enhanced with cation-exchange membranes. Experiments yielded to a selective recovery in the catholyte of 62% of lithium and 33% of cobalt, 80% of the latter electrodeposited at the cathode.This work has received funding from the European Unionâs Horizon 2020 research and innovation programme under the Marie SkĆodowska-Curie grant agreement No. 778045. Financial support from E3TECH Excellence Network under project CTQ2017-90659-REDT (MCIUN, Spain) is acknowledged. Paz-Garcia acknowledges the financial support from the program âProyectos I+D+i en el marco del Programa Operativo FEDER AndalucĂa 2014â2020â, No. UMA18-FEDERJA-279. Villen-Guzman acknowledges the postdoctoral fellowship obtained from the University of Malaga. Cerrillo-Gonzalez acknowledges the FPU grant obtained from the Spanish Ministry of Education