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Xie W, Li W, Wang P, Hao Y, Chen B, Hu L, Wang T, Zhang Q, Liang Y, Jiang G. Unexpected Dioxin Formation During Digestion of Soil with Oxidizing Acids. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:14717-14725. [PMID: 37682840 DOI: 10.1021/acs.est.3c03682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/10/2023]
Abstract
Dioxins, such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), are among the most toxic unintentionally produced persistent organic pollutants, and their emission is of great concern. Herein, we discovered abundant dioxin formation in soil and various organic carbon-containing matrices after digestion with aqua regia. Σ17PCDD/Fs concentrations were in the range of 66.6-142,834 pg/g dw (5.6-17,021 pg WHO2005-TEQ/g dw) in 19 soil samples after digestion with aqua regia for 6 h. Σ17PCDD/Fs concentration was significantly and positively correlated with soil organic carbon content (R2 = 0.89; p < 0.01). Compared with cellulose and lignin, humic acid served as an important organic matter component that was converted to PCDD/Fs during soil digestion. Strong oxidation and production of reactive chlorine by aqua regia may be the key factors in the formation of PCDD/Fs. The yearly emission of PCDD/Fs due to digestion with strong acids by the inspection and testing industry was estimated to be 83.8 g TEQ in China in 2021 based on the highest level, which was ∼0.9% of the total dioxin inventory in China. Great attention should be paid to unexpected dioxin formation during digestion processes considering the potential risk of release from laboratories and enterprises.
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Affiliation(s)
- Wenjing Xie
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Wenjuan Li
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Pu Wang
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Yanfen Hao
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Bolei Chen
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Ligang Hu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Thanh Wang
- Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping 58183, Sweden
- Department of Thematic Studies─Environmental Change (TemaM), Linköping University, Linköping 58183, Sweden
| | - Qinghua Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yong Liang
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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2
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Moriau L, Stojanovski K, Jovanovič P, Escalera-López D, Cherevko S, Hodnik N. Towards electrochemical iridium recycling in acidic media: effect of the presence of organic molecules and chloride ions. RSC Adv 2023; 13:7980-7987. [PMID: 36909751 PMCID: PMC9997448 DOI: 10.1039/d2ra07142h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 03/04/2023] [Indexed: 03/12/2023] Open
Abstract
The utilization of iridium is expected to surge in the next few years, notably due to the rising implementation of water electrolyzer devices in the energy transition. However, the natural resources of this noble metal are extremely limited and thus its recycling will become of high importance. Unfortunately, iridium is also the most corrosion resistant platinum group metal, making its recovery from waste a difficult and energy-demanding process. Hereby, we study the impact of organics and chloride ions on the electrochemical dissolution of iridium in order to pave the way towards green recycling of this precious metal. We present a 40 times increased dissolution when cycling iridium in presence of HCl and 1 M ethanol compared to HClO4. Our results point towards the direction of destabilizing Ir at relatively mild conditions in acidic media.
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Affiliation(s)
- L Moriau
- Department of Materials Chemistry, National Institute of Chemistry 1000 Ljubljana Slovenia .,Center of Excellence Low-Carbon Technologies 1000 Ljubljana Slovenia
| | - K Stojanovski
- Helmotz-Institute Erlangen Nümberg for Renewable Energy (IEK-11), Forschunszentrum Jülich GmbH Erlangen Germany
| | - P Jovanovič
- Department of Materials Chemistry, National Institute of Chemistry 1000 Ljubljana Slovenia
| | - D Escalera-López
- Helmotz-Institute Erlangen Nümberg for Renewable Energy (IEK-11), Forschunszentrum Jülich GmbH Erlangen Germany
| | - S Cherevko
- Helmotz-Institute Erlangen Nümberg for Renewable Energy (IEK-11), Forschunszentrum Jülich GmbH Erlangen Germany
| | - N Hodnik
- Department of Materials Chemistry, National Institute of Chemistry 1000 Ljubljana Slovenia .,University of Nova Gorica 5000 Nova Gorica Slovenia
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3
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Double recovery and regeneration of Pt/C catalysts: Both platinum from the spent proton exchange membrane fuel cell stacks and carbon from the pomelo peel. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.140918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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4
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Podboršek GK, Kamšek AR, Lončar A, Bele M, Suhadolnik L, Jovanovič P, Hodnik N. Atomically-resolved structural changes of ceramic supported nanoparticulate oxygen evolution reaction Ir catalyst. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.140800] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
The spent automobile catalysts (SAC) is the major secondary source of palladium and the production of SAC is increasing rapidly over years. The price of palladium keeps rising over the years, which demonstrates its preciousness and urgent industrial demand. Recovering palladium from the spent automobile catalysts benefits a lot from economic and environmental protection aspects. This review aims to provide some new considerations of recovering palladium from the spent automotive catalysts by summarizing and discussing both hydrometallurgical and pyrometallurgical methods. The processes of pretreatment, leaching/extraction, and separation/recovery of palladium from the spent catalysts are introduced, and related reaction mechanisms and process flows are given, especially detailed for hydrometallurgical methods. Hydrometallurgical methods such as chloride leaching with oxidants possess a high selectivity of palladium and low consumption of energy, and are cost-effective and flexible for different volume feeds compared with pyrometallurgical methods. The recovery ratios of palladium and other platinum-group metals should be the focus of competition since their prices have been rapidly increased over the years, and hence more efficient extractants with high selectivity of palladium even in the complexed leachate should be proposed in the future.
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6
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Song Q, Sun H, Zhang L, Xu Z. Renewable redox couple system for sustainable precious metal recycling from e-waste via halide-regulated potential inversion. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126568. [PMID: 34252663 DOI: 10.1016/j.jhazmat.2021.126568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/04/2021] [Accepted: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Precious metal (PM) retrievement from e-waste is of great significance for reducing virgin mining activity and promoting rare resource sustainability. However, current PM recycling methods rely mainly on caustic aqua regia or unstable sulfur-based ligand, which has caused severe environmental damage and process inefficiency. Here, we propose an environmentally friendly halide-regulated strategy, utilizing milder and renewable oxidant-cupric/ferric ion for facile PM dissolution. This is realized by the synergistic effect of enhanced oxidizing ability of Cu(II) and reduced oxidation potential of PM with halide addition. Electrochemical tests and leaching experiment results show that Cu(II)/Cu(I) redox potential experiences great change with bromide, increasing from 0.4 to 0.75 V. Fast corrosion feature was observed for Au in Cu(II)/Fe(III)-Br- and Pd in Cu(II)/Fe(III)-Cl-, and it can be accelerated by increasing oxidant and halide concentration. Our proposed strategy outperforms traditional methods with stable and fast dissolution, where 2.5 mol/L Br- is appropriate for Au dissolution. Moreover, selective dissolution of base metal, Pd/Ag, and Au can be achieved via ligand alteration and be further combined with electrodeposition technique for multi metal recovery and oxidant regeneration. This halide-regulated strategy can lead PM recycling from pollutive status towards environmentally friendly road.
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Affiliation(s)
- Qingming Song
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
| | - Honghuai Sun
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
| | - Lingen Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
| | - Zhenming Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China.
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7
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Abstract
Platinum and other metals are very scarce materials widely used in the energy and transportation sector among other sectors. Obtaining Platinum is becoming more difficult due to its scarcity on earth and because of the high amount of energy and water used for its extraction. In this regard, the recycling of platinum is necessary for sustainable technologies and for reaching a circular economy towards this expensive and rare metal. Conventional methods for platinum recycling make use of enormous amounts of energy for its recovery, which makes them not very attractive for industry implementation. Furthermore, these processes generate very toxic liquid streams and gas wastes that must be further treated, which do not meet the green environmental point of view of platinum recycling. Consequently, new advanced technologies are arising aiming to reach very high platinum recovery rates while being environmentally friendly and making a huge reduction of energy use compared with the conventional methods. In this review, conventional platinum recovery methods are summarized showing their limitations. Furthermore, new and promising approaches for platinum recovery are reviewed to shed light on about new and greener ways for a platinum circular economy.
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8
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Criticality and Life-Cycle Assessment of Materials Used in Fuel-Cell and Hydrogen Technologies. SUSTAINABILITY 2021. [DOI: 10.3390/su13063565] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The purpose of this paper is to obtain relevant data on materials that are the most commonly used in fuel-cell and hydrogen technologies. The focus is on polymer-electrolyte-membrane fuel cells, solid-oxide fuel cells, polymer-electrolyte-membrane water electrolysers and alkaline water electrolysers. An innovative, methodological approach was developed for a preliminary material assessment of the four technologies. This methodological approach leads to a more rapid identification of the most influential or critical materials that substantially increase the environmental impact of fuel-cell and hydrogen technologies. The approach also assisted in amassing the life-cycle inventories—the emphasis here is on the solid-oxide fuel-cell technology because it is still in its early development stage and thus has a deficient materials’ database—that were used in a life-cycle assessment for an in-depth material-criticality analysis. All the listed materials—that either are or could potentially be used in these technologies—were analysed to give important information for the fuel-cell and hydrogen industries, the recycling industry, the hydrogen economy, as well as policymakers. The main conclusion from the life-cycle assessment is that the polymer-electrolyte-membrane water electrolysers have the highest environmental impacts; lower impacts are seen in polymer-electrolyte-membrane fuel cells and solid-oxide fuel cells, while the lowest impacts are observed in alkaline water electrolysers. The results of the material assessment are presented together for all the considered materials, but also separately for each observed technology.
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9
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Smiljanić M, Petek U, Bele M, Ruiz-Zepeda F, Šala M, Jovanovič P, Gaberšček M, Hodnik N. Electrochemical Stability and Degradation Mechanisms of Commercial Carbon-Supported Gold Nanoparticles in Acidic Media. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2021; 125:635-647. [PMID: 33488908 PMCID: PMC7818511 DOI: 10.1021/acs.jpcc.0c10033] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/28/2020] [Indexed: 06/12/2023]
Abstract
Electrochemical stability of a commercial Au/C catalyst in an acidic electrolyte has been investigated by an accelerated stress test (AST), which consisted of 10,000 voltammetric scans (1 V/s) in the potential range between 0.58 and 1.41 VRHE. Loss of Au electrochemical surface area (ESA) during the AST pointed out to the degradation of Au/C. Coupling of an electrochemical flow cell with ICP-MS showed that only a minor amount of gold is dissolved despite the substantial loss of gold ESA during the AST (∼35% of initial value remains at the end of the AST). According to the electrochemical mass spectrometry experiments, carbon corrosion occurs during the AST but to a minor extent. By using identical location scanning electron microscopy and identical location transmission electron microscopy, it was possible to discern that the dissolution of small Au particles (<5 nm) within the polydisperse Au/C sample is the main degradation mechanism. The mass of such particles gives only a minor contribution to the overall Au mass of the polydisperse sample while giving a major contribution to the overall ESA, which explains a significant loss of ESA and minor loss of mass during the AST. The addition of low amounts of chloride anions (10-4 M) substantially promoted the degradation of gold nanoparticles. At an even higher concentration of chlorides (10-2 M), the dissolution of gold was rather effective, which is useful from the recycling point of view when rapid leaching of gold is desirable.
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Affiliation(s)
- Milutin Smiljanić
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, 1000 Ljubljana, Slovenia
- Laboratory
for Atomic Physics, Institute for Nuclear Sciences Vinča, University of Belgrade, Mike Alasa 12-14, 11001 Belgrade, Serbia
| | - Urša Petek
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, 1000 Ljubljana, Slovenia
| | - Marjan Bele
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, 1000 Ljubljana, Slovenia
| | - Francisco Ruiz-Zepeda
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, 1000 Ljubljana, Slovenia
- Department
of Physics and Chemistry of Materials, Institute
of Metals and Technology, Lepi pot 11, 1000 Ljubljana, Slovenia
| | - Martin Šala
- Department
of Analytical Chemistry, National Institute
of Chemistry, Hajdrihova
19, 1000 Ljubljana, Slovenia
| | - Primož Jovanovič
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, 1000 Ljubljana, Slovenia
| | - Miran Gaberšček
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, 1000 Ljubljana, Slovenia
- Faculty
of Chemistry and Chemical Technology, University
of Ljubljana, Večna
pot 113, 1000 Ljubljana, Slovenia
| | - Nejc Hodnik
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, 1000 Ljubljana, Slovenia
- University
of Nova Gorica, Vipavska
13, 5000 Nova Gorica, Slovenia
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10
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Ambolikar AS, Guin SK. Template‐free Electrosynthesis of Platinum Nano‐Cauliflowers for Catalysing Electron Transfer Reaction of Plutonium. ELECTROANAL 2020. [DOI: 10.1002/elan.202060058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Arvind S. Ambolikar
- Fuel Chemistry Division Bhabha Atomic Research Centre, Trombay Mumbai 400085 India
- Homi Bhabha National Institute, Anushakti Nagar Mumbai 400094 India
| | - Saurav K. Guin
- Fuel Chemistry Division Bhabha Atomic Research Centre, Trombay Mumbai 400085 India
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11
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Deng X, Saito J, Kaksonen A, Okamoto A. Enhancement of cell growth by uncoupling extracellular electron uptake and oxidative stress production in sediment sulfate-reducing bacteria. ENVIRONMENT INTERNATIONAL 2020; 144:106006. [PMID: 32795748 DOI: 10.1016/j.envint.2020.106006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/25/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
Microbial extracellular electron uptake (EEU) from solid electron donors has critical implications for microbial energy acquisition in energy-limited environments as well as electrochemical microbial technologies. Although EEU supplies sufficient energy to support cellular growth, additional soluble electron donors are required for most microbes to grow on electrode surfaces. Here, we demonstrated that the minimization of exogenous and endogenous oxidative stress greatly enhanced the growth rate of the sediment EEU-capable sulfate-reducing bacterium Desulfovibrio ferrophilus IS5 on an electrode without the addition of a soluble electron donor. Single-cell activity analysis by nanoscale secondary ion mass spectrometry showed that the metabolic activity of IS5 cells on the electrode was significantly enhanced following incubation in an H-type reactor, which was configured to reduce the exposure of cells to the potential oxidative stress source of the Pt counter electrode (CE). Additionally, the highest metabolic activity was observed at an electrode potential of -0.4 V (versus the standard hydrogen electrode), where electron uptake rate was not at peak. Compared to a single-chamber reactor, incubation in an H-type reactor at -0.4 V shortened the cell doubling time by 50-fold, which resulted in sufficient anabolism for cell replication (15N/Ntotal > 50%). The production of strongly oxidizing species at the CE was confirmed by X-ray photoelectron spectroscopy and inductively coupled plasma mass spectrometry analyses. Transcriptome analysis revealed overexpression of antioxidative genes in cells incubated at a potential with higher current production. These results suggested that higher levels of endogenous oxidative species were produced by a more reduced electron-transport chain from trace amounts of oxygen in the reactor, thereby lowering cell activity. In conclusion, EEU may enable sediment microbes to undergo enhanced cell growth and to find niches on minerals under anaerobic energy-limited conditions, where oxidative stress is much less likely to be present.
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Affiliation(s)
- Xiao Deng
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan; Center for Sensor and Actuator Material, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan; School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku 113-8656, Japan; CSIRO Land and Water, 147 Underwood Avenue, Floreat, WA 6014, Australia
| | - Junki Saito
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan; School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku 113-8656, Japan
| | - Anna Kaksonen
- CSIRO Land and Water, 147 Underwood Avenue, Floreat, WA 6014, Australia; School of Biomedical Sciences, University of Western Australia, 35 Stirling Highway, Nedlands, WA 6009, Australia
| | - Akihiro Okamoto
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan; Center for Sensor and Actuator Material, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan; Graduate School of Chemical Sciences and Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
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12
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Bharti A, Natarajan R. Recovery of expensive Pt/C catalysts from the end-of-life membrane electrode assembly of proton exchange membrane fuel cells. RSC Adv 2020; 10:35057-35061. [PMID: 35515650 PMCID: PMC9056845 DOI: 10.1039/d0ra06640k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/05/2020] [Indexed: 12/01/2022] Open
Abstract
A simple and economical route using an environmental friendly solvent is reported for recovering catalyst from the end-of-life membrane electrode assembly. This precious component is recovered in the form of Pt/C and ionomer powder. The catalyst exhibited an electrochemical surface area of 42 m2 g−1 and remarkable stability, showcasing its potential for second life applications. A sustainable approach for the recovery of EoL MEAs and possibility of pushing the recovered products back into the supply chain.![]()
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Affiliation(s)
- Abha Bharti
- Centre for Fuel Cell Technology, International Advanced Research Centre for Powder Metallurgy and New Materials IITM-Research Park Chennai-600113 India
| | - Rajalakshmi Natarajan
- Centre for Fuel Cell Technology, International Advanced Research Centre for Powder Metallurgy and New Materials IITM-Research Park Chennai-600113 India
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13
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Kormányos A, Speck FD, Mayrhofer KJJ, Cherevko S. Influence of Fuels and pH on the Dissolution Stability of Bifunctional PtRu/C Alloy Electrocatalysts. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02094] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Attila Kormányos
- Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Forschungszentrum Jülich, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Florian D. Speck
- Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Forschungszentrum Jülich, Egerlandstraße 3, 91058 Erlangen, Germany
- Department of Chemical and Biological Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstaße 3, 91058 Erlangen, Germany
| | - Karl J. J. Mayrhofer
- Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Forschungszentrum Jülich, Egerlandstraße 3, 91058 Erlangen, Germany
- Department of Chemical and Biological Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstaße 3, 91058 Erlangen, Germany
| | - Serhiy Cherevko
- Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Forschungszentrum Jülich, Egerlandstraße 3, 91058 Erlangen, Germany
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14
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Wei J, Chen YX, Magnussen OM. Vacancy dynamics on CO-covered Pt(111) electrodes. Chem Commun (Camb) 2020; 56:8309-8312. [PMID: 32573589 DOI: 10.1039/d0cc04046k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In situ video-STM studies of Pt(111) electrodes in CO-saturated 0.1 M H2SO4 solution are presented, which reveal the presence of defined point defects in the CO pre-oxidation regime, where the surface is covered by a highly dynamic apparent (1 × 1)-CO adlayer. These defects are generated at the Pt steps and can switch between a mobile and an immobile state. They are assigned to diffusing vacancies in the Pt surface layer, induced by interaction of the highly mobile CO adsorbates with Pt surface atoms at potentials as low as 0.30 VAg/AgCl.
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Affiliation(s)
- Jie Wei
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei 230026, China
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15
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Electrochemical Recycling of Platinum Group Metals from Spent Catalytic Converters. METALS 2020. [DOI: 10.3390/met10060822] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Platinum group metals (PGMs: Pt, Pd, and Rh) are used extensively by the industry, while the natural resources are limited. The PGM concentration in spent catalytic converters is 100 times larger than in natural occurring ores. Traditional PGM methods use high temperature furnaces and strong oxidants, thus polluting the environment. Electrochemical studies showed that platinum can be converted to their chloride form. The amount of dissolved PGM was monitored by inductively coupled plasma-optical emission spectroscopy and the structure was identified by ultraviolet-visible spectroscopy. An electrochemistry protocol was designed to maximize platinum dissolution, which was then used for a spent catalytic converter. A key finding is the use of potential step that enhances the dissolution rate by a factor of 4. Recycling rates as high as 50% were achieved in 24 h without any pretreatment of the catalyst. The method developed herein is part of a current need to make the PGM recycling process more sustainable.
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16
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Sharma R, Morgen P, Andersen SM. Platinum recycling through electroless dissolution under mild conditions using a surface activation assisted Pt-complexing approach. Phys Chem Chem Phys 2020; 22:13030-13040. [PMID: 32478339 DOI: 10.1039/c9cp06066a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
High industrial demand and limited global abundance of precious metals (PMs) make their recycling essential for industrial and societal sustainability. Owing to their high surface-to-volume ratio, recycling of nanoparticulate precious metals through dissolution in dilute acids at room temperature is quite relevant. However, their dissolution by approaches such as the cyclic oxidation-reduction of metal surfaces through surface potential manipulation may not be suitable for large-scale production. Here, we demonstrate fast dissolution of Pt-nanoparticles under mild conditions (normal temperature and pressure) in Cl- containing dilute acidic/neutral baths without using cyclic oxidation-reduction. We demonstrate that the dissolution of Pt nanoparticles through [PtClx]2- complexing is hindered by blockage of the Pt surface due to adsorption of non-oxide species (impurities), a phenomenon termed herein as non-oxide passivation (NOP). The nanoparticles can be kept active for the [PtClx]2- complexing through removal of the adsorbed species by surface activation, a process to remove the NOP layer by application of cyclic/continuous perturbation. As an example, average % dissolution rate (calculated on initial Pt loading) increases from ∼10% per h (∼30% dissolution in 3 h) for dissolution without NOP removal to ∼19% per h (∼55% dissolution in 3 h) for dissolution through cyclic activation of the Pt surface by HCl-water cycling. The approach may be implemented with a range of cost-efficient and non-toxic reagents for industrial-scale and environmentally friendly recycling of Pt.
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Affiliation(s)
- Raghunandan Sharma
- Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
| | - Per Morgen
- Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
| | - Shuang Ma Andersen
- Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
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Wang G, Li F, Li L, Zhao J, Ruan X, Ding W, Cai J, Lu A, Pei Y. In Situ Synthesis of Ag-Fe 3O 4 Nanoparticles Immobilized on Pure Cellulose Microspheres as Recyclable and Biodegradable Catalysts. ACS OMEGA 2020; 5:8839-8846. [PMID: 32337446 PMCID: PMC7178767 DOI: 10.1021/acsomega.0c00437] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/01/2020] [Indexed: 05/09/2023]
Abstract
The preparation of reusable and eco-friendly materials from renewable biomass resources such as cellulose is an inevitable choice for sustainable development. In this work, cellulose was dissolved in 7 wt % NaOH/12 wt % urea aqueous solution at -12 °C with rapid stirring. Cellulose microspheres (Cels) were fabricated by a sol-gel transition method. Subsequently, novel magnetic Ag-Fe3O4 nanoparticles (NPs) supported on cellulose microspheres were successfully constructed by an in situ one-pot synthesis. The magnetic cellulose microspheres (MCels) displayed a spherical shape with mesoporous structure and had a narrow particle size distribution (10-20 μm). Many nanopores with a pore diameter of 5-40 nm were observed in MCels. The Ag-Fe3O4 NPs were immobilized by anchoring with the hydroxyl groups on the surface of Cels. MCels were applied as a microreactor to evaluate their catalytic activities. 4-Nitrophenol (4-NP) could be reduced to 4-aminophenol (4-AP) in 5 min, catalyzed by MCels. Moreover, the magnetic microspheres exhibited a small hysteresis loop and low coercivity. Thus, MCels could be quickly gathered in water under a magnetic field in 10 s, as well as almost 9 cycle times, maintaining relatively high catalytic activity. In this work, cellulose matrix as the catalyst support could be biodegraded completely in the environment. It provided a green process for the utilization of biomass in nanocatalytic applications.
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Affiliation(s)
- Guozhen Wang
- Key
Laboratory for Deep Processing of Major Grain and Oil, College of
Food Science and Engineering, Wuhan Polytechnic
University, Wuhan 430023, China
| | - Fei Li
- Key
Laboratory for Deep Processing of Major Grain and Oil, College of
Food Science and Engineering, Wuhan Polytechnic
University, Wuhan 430023, China
| | - Lan Li
- Key
Laboratory for Deep Processing of Major Grain and Oil, College of
Food Science and Engineering, Wuhan Polytechnic
University, Wuhan 430023, China
| | - Jiayu Zhao
- Key
Laboratory for Deep Processing of Major Grain and Oil, College of
Food Science and Engineering, Wuhan Polytechnic
University, Wuhan 430023, China
| | - Xinxuan Ruan
- Key
Laboratory for Deep Processing of Major Grain and Oil, College of
Food Science and Engineering, Wuhan Polytechnic
University, Wuhan 430023, China
| | - Wenping Ding
- Key
Laboratory for Deep Processing of Major Grain and Oil, College of
Food Science and Engineering, Wuhan Polytechnic
University, Wuhan 430023, China
| | - Jie Cai
- Key
Laboratory for Deep Processing of Major Grain and Oil, College of
Food Science and Engineering, Wuhan Polytechnic
University, Wuhan 430023, China
| | - Ang Lu
- College
of Chemistry and Molecular Sciences, Wuhan
University, Wuhan 430072, China
| | - Ying Pei
- School
of Materials Science and Engineering, Zhengzhou
University, Zhengzhou 450001, China
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18
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Zhu J, Hu S, Zeng Z, Li WX. First-principles investigation of electrochemical dissolution of Pt nanoparticles and kinetic simulation. J Chem Phys 2019; 151:234711. [PMID: 31864240 DOI: 10.1063/1.5129631] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Dissolution is the primary route of Pt nanoparticle degradation in electrochemical devices, e.g., fuel cells. Investigation of potential-dependent dissolution kinetics of Pt nanoparticles is crucial to optimize the nanoparticle size and operating conditions for better performance. A mean-field kinetic theory under the steady-state approximation, combined with atomistic thermodynamics and Wulff construction, was developed to study the interplay between oxygen chemisorption, electrode potential, and particle size on the dissolution of Pt nanoparticles. We found that although oxygen chemisorption from electrode potential-induced water splitting can stabilize Pt nanoparticles through decreasing the surface energy and increasing the redox potential, the electrode potential plays a more decisive role in facilitating the dissolution of Pt nanoparticles. In comparison with the minor effect of oxygen chemisorption, an increase in the particle size, though reducing the dispersion, has a more significant effect on the suppression of the dissolution. These theoretical understandings on the effects of electrode potential and particle size on the dissolution are crucial for optimizing the nanoparticle size under oxidative operating conditions.
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Affiliation(s)
- Jing Zhu
- Department of Chemical Physics, School of Chemistry and Materials Science, iCHeM, CAS Excellence Center for Nanoscience, University of Science and Technology of China, Hefei 230026, Anhui, China
| | - Sulei Hu
- Department of Chemical Physics, School of Chemistry and Materials Science, iCHeM, CAS Excellence Center for Nanoscience, University of Science and Technology of China, Hefei 230026, Anhui, China
| | - Zhenhua Zeng
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - Wei-Xue Li
- Department of Chemical Physics, School of Chemistry and Materials Science, iCHeM, CAS Excellence Center for Nanoscience, University of Science and Technology of China, Hefei 230026, Anhui, China
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19
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Moriau LJ, Bele M, Vižintin A, Ruiz-Zepeda F, Petek U, Jovanovič P, Šala M, Gaberšček M, Hodnik N. Synthesis and Advanced Electrochemical Characterization of Multifunctional Electrocatalytic Composite for Unitized Regenerative Fuel Cell. ACS Catal 2019. [DOI: 10.1021/acscatal.9b03385] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Léonard Jean Moriau
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
- Jozef Stefan International Postgraduate School, Jamova 39, SI-1000, Ljubljana, Slovenia
| | - Marjan Bele
- Department of Materials Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Alen Vižintin
- Department of Materials Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Francisco Ruiz-Zepeda
- Department of Materials Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
- Department of Physics and Chemistry of Materials, Institute of Metals and Technology, Lepi pot 11, SI-1000 Ljubljana, Slovenia
| | - Urša Petek
- Department of Materials Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Primož Jovanovič
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Martin Šala
- Department of Analytical Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Miran Gaberšček
- Department of Materials Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Nejc Hodnik
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
- Jozef Stefan International Postgraduate School, Jamova 39, SI-1000, Ljubljana, Slovenia
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20
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Sharma R, Simonsen SB, Morgen P, Andersen SM. Inhibition of Ostwald ripening through surface switching species during potentiodynamic dissolution of platinum nanoparticles as an efficient strategy for platinum group metal (PGM) recovery. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.134662] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Sharma R, Rode Nielsen K, Brilner Lund P, Bredmose Simonsen S, Grahl‐Madsen L, Ma Andersen S. Sustainable Platinum Recycling through Electrochemical Dissolution of Platinum Nanoparticles from Fuel Cell Electrodes. ChemElectroChem 2019. [DOI: 10.1002/celc.201900846] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Raghunandan Sharma
- Department of Chemical Engineering, Biotechnology and Environmental Technology University of Southern Denmark Campusvej 55 DK-5230 Odense M Denmark
| | - Kasper Rode Nielsen
- Department of Chemical Engineering, Biotechnology and Environmental Technology University of Southern Denmark Campusvej 55 DK-5230 Odense M Denmark
| | - Peter Brilner Lund
- Department of Chemical Engineering, Biotechnology and Environmental Technology University of Southern Denmark Campusvej 55 DK-5230 Odense M Denmark
| | - Søren Bredmose Simonsen
- Technical University of Denmark Department of Energy Conversion and Storage Frederiksborgvej 399 4000 Roskilde Denmark
| | | | - Shuang Ma Andersen
- Department of Chemical Engineering, Biotechnology and Environmental Technology University of Southern Denmark Campusvej 55 DK-5230 Odense M Denmark
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22
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Lin CX, Gu JL, Cao JM. The acute toxic effects of platinum nanoparticles on ion channels, transmembrane potentials of cardiomyocytes in vitro and heart rhythm in vivo in mice. Int J Nanomedicine 2019; 14:5595-5609. [PMID: 31413565 PMCID: PMC6660630 DOI: 10.2147/ijn.s209135] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 06/12/2019] [Indexed: 12/02/2022] Open
Abstract
Background Platinum nanoparticles (PtNPs) have been considered a nontoxic nanomaterial and been clinically used in cancer chemotherapy. PtNPs can also be vehicle exhausts and environmental pollutants. These situations increase the possibility of human exposure to PtNPs. However, the potential biotoxicities of PtNPs including that on cardiac electrophysiology have been poorly understood. Methods Ion channel currents of cardiomyocytes were recorded by patch clamp. Heart rhythm was monitored by electrocardiogram recording. Morphology and characteristics of PtNPs were examined by transmission electron microscopy, dynamic light scattering and electrophoretic light scattering analyses. Results In cultured neonatal mice ventricular cardiomyocytes, PtNPs with diameters 5 nm (PtNP-5) and 70 nm (PtNP-70) concentration-dependently (10–9 – 10–5 g/mL) depolarized the resting potentials, suppressed the depolarization of action potentials and delayed the repolarization of action potentials. At the ion channel level, PtNPs decreased the current densities of INa, IK1 and Ito channels, but did not affect the channel activity kinetics. In vivo, PtNP-5 and PtNP-70 dose-dependently (3–10 mg/kg, i.v.) decreased the heart rate and induced complete atrioventricular conduction block (AVB) at higher doses. Both PtNP-5 and PtNP-70 (10–9 – 10–5 g/mL) did not significantly increase the generation of ROS and leak of lactate dehydrogenase (LDH) from cardiomyocytes within 5 mins after exposure except that only very high PtNP-5 (10–5 g/mL) slightly increased LDH leak. The internalization of PtNP-5 and PtNP-70 did not occur within 5 mins but occurred 1 hr after exposure. Conclusion PtNP-5 and PtNP-70 have similar acute toxic effects on cardiac electrophysiology and can induce threatening cardiac conduction block. These acute electrophysiological toxicities of PtNPs are most likely caused by a nanoscale interference of PtNPs on ion channels at the extracellular side, rather than by oxidative damage or other slower biological processes.
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Affiliation(s)
- Cai-Xia Lin
- Key Laboratory of Cellular Physiology (Shanxi Medical University), Ministry of Education, Department of Physiology, Shanxi Medical University, Taiyuan, People's Republic of China.,Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, People's Republic of China
| | - Jing-Li Gu
- Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, People's Republic of China
| | - Ji-Min Cao
- Key Laboratory of Cellular Physiology (Shanxi Medical University), Ministry of Education, Department of Physiology, Shanxi Medical University, Taiyuan, People's Republic of China
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23
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Kasian O, Geiger S, Mayrhofer KJJ, Cherevko S. Electrochemical On-line ICP-MS in Electrocatalysis Research. CHEM REC 2018; 19:2130-2142. [PMID: 30589199 DOI: 10.1002/tcr.201800162] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 11/20/2018] [Indexed: 01/13/2023]
Abstract
Electrocatalyst degradation due to dissolution is one of the major challenges in electrochemical energy conversion technologies such as fuel cells and electrolysers. While tendencies towards dissolution can be grasped considering available thermodynamic data, the kinetics of material's stability in real conditions is still difficult to predict and have to be measured experimentally, ideally in-situ and/or on-line. On-line inductively coupled plasma mass spectrometry (ICP-MS) is a technique developed recently to address exactly this issue. It allows time- and potential-resolved analysis of dissolution products in the electrolyte during the reaction under dynamic conditions. In this work, applications of on-line ICP-MS techniques in studies embracing dissolution of catalysts for oxygen reduction (ORR) and evolution (OER) as well as hydrogen oxidation (HOR) and evolution (HER) reactions are reviewed.
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Affiliation(s)
- Olga Kasian
- Department of Interface Chemistry and Surface Engineering, Max-Planck-Institut für Eisenforschung GmbH, 40237, Düsseldorf, Germany
| | - Simon Geiger
- Department of Interface Chemistry and Surface Engineering, Max-Planck-Institut für Eisenforschung GmbH, 40237, Düsseldorf, Germany.,Current address: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569, Stuttgart, Germany
| | - Karl J J Mayrhofer
- Department of Interface Chemistry and Surface Engineering, Max-Planck-Institut für Eisenforschung GmbH, 40237, Düsseldorf, Germany.,Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Forschungszentrum Jülich, 91058, Erlangen, Germany.,Department of Chemical and Biological Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058, Erlangen, Germany
| | - Serhiy Cherevko
- Department of Interface Chemistry and Surface Engineering, Max-Planck-Institut für Eisenforschung GmbH, 40237, Düsseldorf, Germany.,Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Forschungszentrum Jülich, 91058, Erlangen, Germany
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24
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Sharma R, Gyergyek S, Andersen SM. Environmentally and Industrially Friendly Recycling of Platinum Nanoparticles Through Electrochemical Dissolution-Electrodeposition in Acid-Free/Dilute Acidic Electrolytes. CHEMSUSCHEM 2018; 11:3742-3750. [PMID: 30204304 DOI: 10.1002/cssc.201801604] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 08/17/2018] [Indexed: 06/08/2023]
Abstract
A process to recycle platinum from industrial waste, for example, spent catalysts from polymer fuel cells and electrolyzers, through potentiodynamic dissolution along with potentiostatic electrodeposition in dilute acidic/acid-free baths has been explored. During potentiodynamic dissolution, owing to Ostwald ripening, redeposition of the dissolved Pt species on source nanoparticles becomes significant, leading to lower overall dissolution efficiency. Alternatively, high concentrations of Pt-complexing agents (e.g., Cl- ) are required to stabilize dissolved species through complex formation. The present process overcomes those limitations by removing the dissolved Pt species continuously through electrodepositing them in the form of Pt0 on another electrode. Such a process significantly promotes the overall reaction kinetics, and an increase in dissolution rate by a factor of two or more has been observed in non-complexing electrolytes. The process may be implemented for environmentally and industrially friendly recycling of Pt in dilute acidic/acid-free baths, thus eliminating the additional steps such as electrolyte upconcentration and post-dissolution reduction of dissolved Pt species.
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Affiliation(s)
- Raghunandan Sharma
- Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Sašo Gyergyek
- Department for Materials Synthesis, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - Shuang Ma Andersen
- Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
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25
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Ibrahim MYS, Denmark SE. Selective extraction of supported Rh nanoparticles under mild, non-acidic conditions with carbon monoxide. JOURNAL OF MATERIALS CHEMISTRY. A 2018; 6:18075-18083. [PMID: 30450207 PMCID: PMC6237428 DOI: 10.1039/c8ta06508j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Owing to their limited supplies, recycling of precious metals, especially rhodium, is vital to sustain the growth of certain nanotechnologies. Here we report a mild, efficient, and selective method for rhodium recovery that relies on the use of carbon monoxide to extract rhodium nanoparticles on various supports in polar solvents. Unlike the traditional recycling technologies, this method operates at low temperature and does not require strong acids. Moreover, the CO-induced leaching is complimentary to leaching by acids in terms of selectivity toward rhodium versus other precious metals and results in metal recovery in the form of reduced metallic clusters. The method performs best on freshly reduced surfaces and can be promoted by the addition of tertiary amines. Besides CO gas, formic acid can also be used as a leachant by decomposition to produce CO by Rh catalysis. The concept of CO-induced leaching could be applied to the extraction of rhodium from nuclear waste and extended to modify rhodium nanoparticle size and composition.
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Affiliation(s)
- Malek Y S Ibrahim
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois, 61801, USA.
| | - Scott E Denmark
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois, 61801, USA.
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26
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27
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Jovanovič P, Hodnik N, Ruiz-Zepeda F, Arčon I, Jozinović B, Zorko M, Bele M, Šala M, Šelih VS, Hočevar S, Gaberšček M. Electrochemical Dissolution of Iridium and Iridium Oxide Particles in Acidic Media: Transmission Electron Microscopy, Electrochemical Flow Cell Coupled to Inductively Coupled Plasma Mass Spectrometry, and X-ray Absorption Spectroscopy Study. J Am Chem Soc 2017; 139:12837-12846. [PMID: 28810123 DOI: 10.1021/jacs.7b08071] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Iridium-based particles, regarded as the most promising proton exchange membrane electrolyzer electrocatalysts, were investigated by transmission electron microscopy and by coupling of an electrochemical flow cell (EFC) with online inductively coupled plasma mass spectrometry. Additionally, studies using a thin-film rotating disc electrode, identical location transmission and scanning electron microscopy, as well as X-ray absorption spectroscopy have been performed. Extremely sensitive online time-and potential-resolved electrochemical dissolution profiles revealed that Ir particles dissolve well below oxygen evolution reaction (OER) potentials, presumably induced by Ir surface oxidation and reduction processes, also referred to as transient dissolution. Overall, thermally prepared rutile-type IrO2 particles are substantially more stable and less active in comparison to as-prepared metallic and electrochemically pretreated (E-Ir) analogues. Interestingly, under OER-relevant conditions, E-Ir particles exhibit superior stability and activity owing to the altered corrosion mechanism, where the formation of unstable Ir(>IV) species is hindered. Due to the enhanced and lasting OER performance, electrochemically pre-oxidized E-Ir particles may be considered as the electrocatalyst of choice for an improved low-temperature electrochemical hydrogen production device, namely a proton exchange membrane electrolyzer.
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Affiliation(s)
- Primož Jovanovič
- Department of Materials Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Nejc Hodnik
- Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Francisco Ruiz-Zepeda
- Department of Materials Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Iztok Arčon
- University of Nova Gorica , Vipavska 13, 5000 Nova Gorica, Slovenia.,Jozef Stefan Institute , Jamova 39, 1000 Ljubljana, Slovenia
| | - Barbara Jozinović
- Department of Materials Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Milena Zorko
- Department of Materials Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Marjan Bele
- Department of Materials Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Martin Šala
- Department of Analytical Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Vid Simon Šelih
- Department of Analytical Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Samo Hočevar
- Department of Analytical Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Miran Gaberšček
- Department of Materials Chemistry, National Institute of Chemistry , Hajdrihova 19, 1000 Ljubljana, Slovenia.,Faculty of Chemistry and Chemical Technology, University of Ljubljana , Večna pot 113, 1000 Ljubljana, Slovenia
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28
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Nag A, Baksi A, Krishnapriya KC, Gupta SS, Mondal B, Chakraborty P, Pradeep T. Synergistic Effect in Green Extraction of Noble Metals and Its Consequences. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201700182] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Abhijit Nag
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence Department of Chemistry Indian Institute of Technology Madras 600036 Chennai India
| | - Ananya Baksi
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence Department of Chemistry Indian Institute of Technology Madras 600036 Chennai India
| | - K. C. Krishnapriya
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence Department of Chemistry Indian Institute of Technology Madras 600036 Chennai India
| | - Soujit Sen Gupta
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence Department of Chemistry Indian Institute of Technology Madras 600036 Chennai India
| | - Biswajit Mondal
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence Department of Chemistry Indian Institute of Technology Madras 600036 Chennai India
| | - Papri Chakraborty
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence Department of Chemistry Indian Institute of Technology Madras 600036 Chennai India
| | - Thalappil Pradeep
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence Department of Chemistry Indian Institute of Technology Madras 600036 Chennai India
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