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Lead leaching behaviors during panel-funnel glass waste separation from cathode-ray tube glass using thermosol, acid etching or mechanical cutting methods. JOURNAL OF SAUDI CHEMICAL SOCIETY 2022. [DOI: 10.1016/j.jscs.2022.101557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Wang F, Xu B, Yang B, Shi T. The lead removal evolution from hazardous waste cathode ray tube funnel glass under enhancement of red mud melting and synthesizing value-added glass-ceramics via reutilization of silicate resources. JOURNAL OF HAZARDOUS MATERIALS 2022; 429:128334. [PMID: 35091191 DOI: 10.1016/j.jhazmat.2022.128334] [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: 11/28/2021] [Revised: 01/19/2022] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
Waste CRT funnel glass (FG) is a typical hazardous waste produced by the electronics industry that contains toxic lead oxide, red mud (RM) is the first waste produced during alumina production. Both of these are extremely difficult to reuse. Here, we report a method to control FG waste, in which RM was used to enhance the removal of Pb from FG via a vacuum thermal process. The removed residual glass was utilized to create glass-ceramics. The results showed that RM can enhance the lead removal from waste CRT funnel glass by the vacuum thermal process. When 30% RM was added, the removal rate reached 98.54%. A significant mechanism of enhancing delead is investigated by a Fourier transform infrared (FTIR) spectrometer and X-ray photoelectron spectroscopy (XPS). The results showed that the -Pb-O-Si-O- network structure was broken by the free calcium ions of RM. Afterward, valuable glass-ceramics with tetragonal-KAlSi2O6 and triclinic-CaSiO3 crystals were synthesized using the residual glass. The Pb, Ba, Cr, and Cu leaching concentrations of the glass-ceramics were well below the regulatory limit (5 mg/L) of the CA-EPA, as measured by the toxicity characteristic leaching procedure (TCLP) test. Overall, the results indicated that RM enhanced the removal of lead during the vacuum thermal process. The synthesis of value-added glass-ceramics reutilized silicate resources from waste cathode ray tube (CRT) funnel glass and RM.
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Affiliation(s)
- Fengkang Wang
- State Key Laboratory of Complex Nonferrous Metal Resources Clear Utilization, Kunming 650093, PR China; National Engineering Laboratory for Vacuum Metallurgy, Kunming 650093, PR China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, PR China; School of Metallurgy and Environment, Central South University, Changsha, PR China
| | - Baoqiang Xu
- State Key Laboratory of Complex Nonferrous Metal Resources Clear Utilization, Kunming 650093, PR China; National Engineering Laboratory for Vacuum Metallurgy, Kunming 650093, PR China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, PR China.
| | - Bin Yang
- State Key Laboratory of Complex Nonferrous Metal Resources Clear Utilization, Kunming 650093, PR China; National Engineering Laboratory for Vacuum Metallurgy, Kunming 650093, PR China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, PR China
| | - Tengteng Shi
- State Key Laboratory of Complex Nonferrous Metal Resources Clear Utilization, Kunming 650093, PR China; National Engineering Laboratory for Vacuum Metallurgy, Kunming 650093, PR China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, PR China
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Chemical-Electrochemical Process Concept for Lead Recovery from Waste Cathode Ray Tube Glass. MATERIALS 2021; 14:ma14061546. [PMID: 33809892 PMCID: PMC8004233 DOI: 10.3390/ma14061546] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/14/2021] [Accepted: 03/18/2021] [Indexed: 11/16/2022]
Abstract
This paper presents a novel approach for the recovery of lead from waste cathode-ray tube (CRT) glass by applying a combined chemical-electrochemical process which allows the simultaneous recovery of Pb from waste CRT glass and electrochemical regeneration of the leaching agent. The optimal operating conditions were identified based on the influence of leaching agent concentration, recirculation flow rate and current density on the main technical performance indicators. The experimental results demonstrate that the process is the most efficient at 0.6 M acetic acid concentration, flow rate of 45 mL/min and current density of 4 mA/cm2. The mass balance data corresponding to the recycling of 10 kg/h waste CRT glass in the identified optimal operating conditions was used for the environmental assessment of the process. The General Effect Indices (GEIs), obtained through the Biwer Heinzle method for the input and output streams of the process, indicate that the developed recovery process not only achieve a complete recovery of lead but it is eco-friendly as well.
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Qi Y, Xiao X, Lu Y, Shu J, Wang J, Chen M. Cathode ray tubes glass recycling: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 650:2842-2849. [PMID: 30373061 DOI: 10.1016/j.scitotenv.2018.09.383] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 09/25/2018] [Accepted: 09/29/2018] [Indexed: 06/08/2023]
Abstract
With the rapid development in kinescope technologies, Cathode Ray Tubes (CRTs) now are almost completely replaced by thinner and lighter flat panel displays, such as liquid crystal displays (LCD), plasma display panels (PDP) and light emitting diode (LED) displays. Waste CRT glass contains many poisonous and harmful substances, especially lead. If it is not properly disposed of, it would pose a serious threat to the environment and human health. This paper reviews the existing waste CRT glass recycling technologies, analyses the obstacles that hinder their industrial application, pinpoints its future directions. This paper also points out the academic conflict in the risk of lead contained CRT glass and proposes a basic rule for waste treatment and disposal: the lower risk principle. The results of this study could help to understand waste CRT glass recycling and guide its future research and development.
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Affiliation(s)
- Yaping Qi
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Mianyang 621010, PR China
| | - Xiang Xiao
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, PR China; Changsha Research Institute of Nonferrous Metallurgy, Changsha 410011, PR China
| | - Yan Lu
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Mianyang 621010, PR China
| | - Jiancheng Shu
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Mianyang 621010, PR China
| | - Jianbo Wang
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Mianyang 621010, PR China
| | - Mengjun Chen
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Mianyang 621010, PR China.
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Lu X, Ning XA, Chen D, Chuang KH, Shih K, Wang F. Lead extraction from Cathode Ray Tube (CRT) funnel glass: Reaction mechanisms in thermal reduction with addition of carbon (C). WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 76:671-678. [PMID: 29650298 DOI: 10.1016/j.wasman.2018.04.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 03/27/2018] [Accepted: 04/06/2018] [Indexed: 06/08/2023]
Abstract
This study quantitatively determined the extraction of lead from CRT funnel glass and examined the mechanisms of thermally reducing lead in the products of sintering Pb-glass with carbon in the pre-heated furnace. The experimentally derived results indicate that a 90.3 wt% lead extraction efficiency can be achieved with 20 wt% of C addition at 950 °C for 3 min under air. The formation of viscous semi-liquid glass blocked the oxygen supply between the interaction of C and Pb-glass, and was highly effective for the extraction of metallic Pb. A maximum of 87.3% lead recover was obtained with a C to Na2CO3 ratio of 1/3 at 1200 °C. The decrease of C/Na2CO3 ratio enhanced the metallic lead recovery by increasing the glass viscosity for effective sedimentation of metallic lead in the bottom. However, with the further increase of temperature and treatment time, re-vitrification of lead back to silicate-glass matrix was detected in both Pb-glass/C and Pb-glass/C/Na2CO3 systems. The findings indicated that with proper controls, using C as an inexpensive reagent can effectively reduce treatment time and energy, which is crucial to a waste-to-resource technology for economically recovering lead from the waste CRT glass.
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Affiliation(s)
- Xingwen Lu
- School of Environmental Science and Engineering and Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region
| | - Xun-An Ning
- School of Environmental Science and Engineering and Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Da Chen
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Kui-Hao Chuang
- Department of Safety Health and Environmental Engineering, Central Taiwan University of Science and Technology, Taichung 406, Taiwan, ROC
| | - Kaimin Shih
- Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region
| | - Fei Wang
- Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region; School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China.
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Wang C, Yao D, Liu Y, Wu Y, Shen J. Development of a novel recycling system for waste cathode ray tube funnel glass based on the integration of nanoscale Fe 0 with ball milling. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 76:679-686. [PMID: 29643009 DOI: 10.1016/j.wasman.2018.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 04/02/2018] [Accepted: 04/04/2018] [Indexed: 06/08/2023]
Abstract
A novel and effective system was developed for recycling cathode ray tube (CRT) funnel glass wastes. Initially, the combination of nanoscale Fe0 with ball milling promoted lead transfer that was strongly encapsulated in the glass inner structure to the surface of funnel glass and/or adhere to iron substance due to the collapse of SiO bonds. This condition enhanced the dissolution of lead in the acid solution. A high lead extraction rate of 97.8% from funnel glass was achieved through nitric acid leaching by optimizing the operational parameters (Fe0/funnel glass mass ratio, 0.5:1; ball milling time; 72 h). Subsequently, lead sulfate, iron hydroxides, and sodium nitrate were gradually recovered from the acid leachate by using three simple operations, namely, sulfation, alkali neutralization, and salt evaporation. Meanwhile, the leaching results of short-term toxicity characteristic leaching (TCLP) and long-term multiple extraction procedures (MEP) clearly demonstrated that the residual high silica products (after acid leaching) had no impact on the environment and could be used to synthesize high value-added zeolites as raw materials. With the addition of Al sources, the complete conversion of high silica residues into high crystalline zeolites with high cation exchange capacity value was realized by applying an alkaline fusion method during the hydrothermal treatment. Furthermore, lead, NO-3, and SO2-4 concentrations of the resulting drainage were considerably lower than the relevant standard for surface water quality. Therefore, the proposed recycling system provided an eco-friendly and feasible technique for complete reutilization of obsolete CRT funnel glass.
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Affiliation(s)
- Chunfeng Wang
- Henan Key Laboratory for Environmental Pollution Control and Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, School of Environment, Henan Normal University, 46 East Jianshe Road, Xinxiang, Henan Province 453007, China; Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Dan Yao
- Henan Key Laboratory for Environmental Pollution Control and Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, School of Environment, Henan Normal University, 46 East Jianshe Road, Xinxiang, Henan Province 453007, China
| | - Yang Liu
- Henan Key Laboratory for Environmental Pollution Control and Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, School of Environment, Henan Normal University, 46 East Jianshe Road, Xinxiang, Henan Province 453007, China
| | - Yufan Wu
- Henan Key Laboratory for Environmental Pollution Control and Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, School of Environment, Henan Normal University, 46 East Jianshe Road, Xinxiang, Henan Province 453007, China
| | - Jinyou Shen
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
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Lv J, Yang H, Jin Z, Zhao M. Lead extraction and glass-ceramics synthesis from waste cathode ray tube funnel glass through cooperative smelting process with coal fly ash. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 76:687-696. [PMID: 29550068 DOI: 10.1016/j.wasman.2018.03.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 02/09/2018] [Accepted: 03/09/2018] [Indexed: 06/08/2023]
Abstract
In this study, a novel process was developed for extracting lead from the hazardous waste cathode ray tube (CRT) funnel glass and simultaneously producing glass-ceramics. CRT funnel glass was mixed with coal fly ash and subjected to carbon thermal reduction with the addition of CaO. The homogeneous glass melt and reduced metallic lead were quenched in water. Glass-ceramics were produced from the parent glass through an appropriate heat treatment. The optimum carbon loading amount (calculated as the molar ratio of C/PbO), CaO/SiO2 ratio, smelting temperature and holding time for lead recovery were 1.0, 0.3-0.6, 1450 °C and 2 h, respectively. Under these conditions, more than 95% of lead can be extracted from the funnel glass and a low lead content of the resultant parent glass below 0.6 wt% was successfully achieved. CaO behaved as a network modifier to reduce the viscosity of the glass and also acted as a substitution to release lead oxide from the silicate network structure, resulting in a high lead separation efficiency. X-ray diffraction (XRD) analysis revealed that the main crystalline phase was gehlenite when 50-70 wt% funnel glass was added. Scanning electron microscopy (SEM) observation showed that well-crystallized crystals occurred in the specimens with 50-70 wt% funnel glass additions, whereas the specimens with 40 wt% and 80 wt% glass additions exhibited a relative low crystallization degree. Furthermore, property measurements, chemical resistance tests and leaching characteristics of heavy metals confirmed the possibility of engineering and construction applications of the superior glass-ceramic products. Overall results indicate that the process proposed in this paper is an effective and promising approach for reutilization of obsolete CRT funnel glass.
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Affiliation(s)
- Jianfang Lv
- School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China
| | - Hongying Yang
- School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China
| | - Zhenan Jin
- School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China.
| | - Minglei Zhao
- School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China
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Hu B, Hui W. Lead recovery from waste CRT funnel glass by high-temperature melting process. JOURNAL OF HAZARDOUS MATERIALS 2018; 343:220-226. [PMID: 28961502 DOI: 10.1016/j.jhazmat.2017.09.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 09/15/2017] [Accepted: 09/20/2017] [Indexed: 06/07/2023]
Abstract
In this research, a novel and effective process for waste CRT funnel glass treatment was developed. The key to this process is removal of lead from the CRT funnel glass by high-temperature melting process. Sodium carbonate powder was used as a fusion agent, sodium sulfide serves as a catalytic agent and carbon powder acts as reducing agent. Experimental results showed that lead recovery rate increased with an increase in the amount of added sodium carbonate, sodium sulfide, carbonate, temperature and holding time initially, and then reached a stable value. The maximum lead recovery rate was approximately 94%, when the optimum adding amount of sodium carbonate, sodium sulfide, carbonate, temperature and holding time were 25%, 8%, 3.6%, 1200°C and 120min, respectively. In the high-temperature melting process, lead silicate in the funnel glass was firstly reduced, and then removed. The glass slag can be made into sodium and potassium silicate by hydrolysis process. This study proposed a practical and economical process for recovery of lead and utilization of waste glass slag.
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Affiliation(s)
- Biao Hu
- School of Management, Tianjin University of Technology, Tianjin, China; School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin, China
| | - Wenlong Hui
- School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin, China.
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Dias P, Oliveira ED, Veit H. Lead hazard evaluation for cathode ray tube monitors in Brazil. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2018. [DOI: 10.1590/0104-6632.20180351s20160367] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Pablo Dias
- Universidade Federal do Rio Grande do Sul (UFRGS), Brazil
| | | | - Hugo Veit
- Universidade Federal do Rio Grande do Sul (UFRGS), Brazil
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Jani Y, Hogland W. Reduction-melting extraction of trace elements from hazardous waste glass from an old glasswork's dump in the southeastern part of Sweden. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:26341-26349. [PMID: 28944435 PMCID: PMC5719799 DOI: 10.1007/s11356-017-0243-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 09/19/2017] [Indexed: 06/07/2023]
Abstract
At the southeastern part of Sweden, old art and crystal waste glass has been identified as a hazardous waste due to high weight concentrations of Pb (32.398%), Cd (0.085%), and As (1.976%). The reduction-melting technique was used to investigate the extraction of these trace elements from powder waste glass of particle size < 1 mm. Following a factorial design technique, the experimental results of the reduction-melting method showed that 99.9% of Pb, 100% of Cd, and 99% of As could be extracted. For a batch of 10 g powder waste glass, the found experimental and theoretical optimum operating conditions were 1100 °C of melting temperature, 5 g of Na2CO3, 2 g of carbon, and 120 min of melting time. The reduction-melting method displayed promising results which might help in recycling the extracted trace elements and glass compared to the current used solution of landfilling as hazardous wastes.
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Affiliation(s)
- Yahya Jani
- Department of Biology and Environmental Science, Faculty of Health and Life Sciences, Linnaeus University (LNU), Landgången 3, SE-392 31, Kalmar, Sweden.
| | - William Hogland
- Department of Biology and Environmental Science, Faculty of Health and Life Sciences, Linnaeus University (LNU), Landgången 3, SE-392 31, Kalmar, Sweden
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Bursi E, Barbieri L, Lancellotti I, Saccani A, Bignozzi M. Lead waste glasses management: Chemical pretreatment for use in cementitious composites. WASTE MANAGEMENT & RESEARCH : THE JOURNAL OF THE INTERNATIONAL SOLID WASTES AND PUBLIC CLEANSING ASSOCIATION, ISWA 2017; 35:958-966. [PMID: 28681661 DOI: 10.1177/0734242x17715098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
This article investigates the effect of a low-impact chemical treatment based on a nitrilotriacetic acid chelating agent on the reactivity of funnel glass derived from discarded cathode ray tubes. Treated and untreated glass has been recycled either as a supplementary cementing material or as a fine aggregate in cementitious mortars. The effect of the treatment on the chemical and morphological properties of cullets, as well as on the solubility in an alkaline environment has been evaluated. Data so far collected underline a change in glass cullets characteristics that consequently affects their behaviour in cementitious mortars, reducing the pozzolanic activity as supplementary cementing material, but strongly decreasing the tendency towards alkali silica reactions when added as a fine aggregate. The leaching behaviour of lead on treated and untreated glass and on derived composites has been determined to verify the sustainability of the prepared materials.
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Affiliation(s)
- Elena Bursi
- 1 Dipartimento di Ingegneria "Enzo Ferrari" Università di Modena e Reggio Emilia, Modena, Italy
| | - Luisa Barbieri
- 1 Dipartimento di Ingegneria "Enzo Ferrari" Università di Modena e Reggio Emilia, Modena, Italy
| | - Isabella Lancellotti
- 1 Dipartimento di Ingegneria "Enzo Ferrari" Università di Modena e Reggio Emilia, Modena, Italy
| | - Andrea Saccani
- 2 Dipartimento di Ingegneria Civile, Chimica, Ambientale e dei Materiali Università di Bologna, Bologna, Italy
| | - Maria Bignozzi
- 2 Dipartimento di Ingegneria Civile, Chimica, Ambientale e dei Materiali Università di Bologna, Bologna, Italy
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Okada T. Water-soluble lead in cathode ray tube funnel glass melted in a reductive atmosphere. JOURNAL OF HAZARDOUS MATERIALS 2016; 316:43-51. [PMID: 27209518 DOI: 10.1016/j.jhazmat.2016.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 04/28/2016] [Accepted: 05/04/2016] [Indexed: 06/05/2023]
Abstract
In the reduction-melting process, lead can be recovered from cathode ray tube funnel glass (PbO=25wt%); however, resulting glass residues still contain approximately 1-2wt% of unrecovered lead. For environmental protection in the residue disposal or recycling, it is important to evaluate the quantities of water-soluble species among the unrecovered lead. This study examined water-soluble lead species generated in the reduction-melting process of the funnel glass and factors determining their generation. In the reduction-melting, metallic lead was generated by reducing lead oxides in the glass, and a part of the metallic lead remained in the glass residue. Such unrecovered metallic lead can dissolve in water depending on its pH level and was regarded as water-soluble lead. When 10g Na2CO3 was added to 20g funnel glass during reduction-melting, the resulting glass contained high concentrations of sodium. In a water leaching of the glass, the obtained leachate was alkalized by the sodium-rich glass (pH=12.7-13.0). The unrecovered metallic lead in the glass was extracted in the alkalized leachate. The quantity of the unrecovered metallic lead (water-soluble lead) in the glass decreased when the melting time, melting temperature, and carbon dosage were controlled during reduction-melting.
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Affiliation(s)
- Takashi Okada
- Laboratory of Mineral Processing and Resources Recycling, Graduate School of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, 060-8628 Japan.
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