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Pyrolysis characteristics of waste printed circuit boards and distribution pattern of their valuable liquid products

废弃线路板的热解特性及其有价液体产物的分布规律

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Abstract

Pyrolysis is a promising technology to treat waste printed circuit boards (WPCBs) with significant advantages of full source utilization, high separation efficiency and scarce pollutant emissions. In this work, TG and DTG analyses were performed to determine pyrolysis characteristics. The kinetic analysis adopting the Starink Kissinger-Akahira-Sunose (SKAS) model was conducted to confirm the apparent activation energy (Eα). Pyrolysis products were collected using a lab-scale pyrolyzer. GC-MS analysis coupled with MS-DIAL data processing was applied to clarify the distribution pattern of valuable liquid products. The results indicated that the main thermal decomposition of WPCBs occurred within the temperature range of 157–664 °C, with Eα ranging from 80.70 to 279.46 kJ/mol. During pyrolysis, the WPCBs were converted into three kinds of products, in which solid and gas products could be applied in the field of materials and energy. The composition of WPCBs oil products was complicated and sensitive to the pyrolysis temperature. The largest proportion of valuable liquid products (82.94%) was obtained at 600 °C, containing 52.87% monocyclic aromatic phenols, 4.39% polycyclic aromatic phenols, 3.07% brominated phenols, and 22.61% hydrocarbons, respectively. These valuable liquid products would be an attractive alternative as raw materials for the synthesis of phenolic resins and the production of petrochemicals.

摘要

热解技术遵循减量化、无害化和资源化三大固体废弃物处理原则, 是一种有前景的大批量废弃 线路板处置方法。本论文针对废弃线路板热解产物成分复杂及利用价值低的问题, 进行了废弃线路板 热解特性、产物组成及其有价液体产物分布规律的研究, 为后续工业应用提供理论支撑。结果表明, 废弃线路板的热解温区为157~664°C;,表观活化能为80.70~279.46 kJ/mol。废弃线路板在热解过程中 转化为三种产物, 其中固体和气体产物可应用于材料和能源领域。废弃线路板的液体产物组成复杂, 并且对热解温度较为敏感。在600 ℃时热解液体产物中有价组分比例最高(82.94%), 其中单环酚类化 合物占52.87%, 多环酚类化合物占4.39%, 溴酚类化合物占3.07%, 烃类化合物占22.61%。废弃线路 板在热解过程中的有价液体产物可替代酚醛树脂和石化产品中的部分原料。

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References

  1. FORTI V, BALDÉ C P, KUEHR R, et al. The global E-waste monitor 2020: Quantities, flows and the circular economy potential [M]. United Nations University (UNU), 2020. http://ewastemonitor.info/.

  2. YU Lu-ling, HE Wen-zhi, LI Guang-ming, et al. The development of WEEE management and effects of the fund policy for subsidizing WEEE treating in China [J]. Waste Management, 2014, 34(9): 1705–1714. DOI: https://doi.org/10.1016/j.wasman.2014.05.012.

    Article  Google Scholar 

  3. LIN K H, CHIANG H L. Liquid oil and residual characteristics of printed circuit board recycle by pyrolysis [J]. Journal of Hazardous Materials, 2014, 271: 258–265. DOI: https://doi.org/10.1016/j.jhazmat.2014.02.031.

    Article  Google Scholar 

  4. STUHLPFARRER P, LUIDOLD S, ANTREKOWITSCH H. Recycling of waste printed circuit boards with simultaneous enrichment of special metals by using alkaline melts: A green and strategically advantageous solution [J]. Journal of Hazardous Materials, 2016, 307: 17–25. DOI: https://doi.org/10.1016/j.jhazmat.2015.12.007.

    Article  Google Scholar 

  5. WANG Rong, CHEN Men-jun, HUANG Jin-xiu, et al. Copper recycling from waste printed circuit boards by electrokinetics [J]. Journal of Central South University (Science and Technology), 2016, 47: 1436–1440. DOI: https://doi.org/10.11817/j.issn.1672-7207.2016.04.046. (in Chinese)

    Google Scholar 

  6. ZHAN Lu, XU Zhen-ming. State-of-the-art of recycling e-wastes by vacuum metallurgy separation [J]. Environmental Science & Technology, 2014, 48(24): 14092–14102. DOI: https://doi.org/10.1021/es5030383.

    Article  Google Scholar 

  7. GUO Xue-yi, LIU Jing-xin. Optimization of low-temperature alkaline smelting process of crushed metal enrichment originated from waste printed circuit boards [J]. Journal of Central South University, 2015, 22(5): 1643–1650. DOI: https://doi.org/10.1007/s11771-015-2682-8.

    Article  Google Scholar 

  8. CHEN Shu, YANG Yuan-kun, LIU Cong-qiang, et al. Column bioleaching copper and its kinetics of waste printed circuit boards (WPCBs) by Acidithiobacillus ferrooxidans [J]. Chemosphere, 2015, 141: 162–168. DOI: https://doi.org/10.1016/j.chemosphere.2015.06.082.

    Article  Google Scholar 

  9. SOLER A, CONESA J A, IÑIGUEZ M E, et al. Pollutant formation in the pyrolysis and combustion of materials combining biomass and e-waste [J]. The Science of the Total Environment, 2018, 622–623: 1258–1264. DOI: https://doi.org/10.1016/j.scitotenv.2017.12.068.

    Article  Google Scholar 

  10. MARQUES A C, CABRERA MARRERO J M, DE FRAGA MALFATTI C. A review of the recycling of non-metallic fractions of printed circuit boards [J]. SpringerPlus, 2013, 2: 521. DOI: https://doi.org/10.1186/2193-1801-2-521.

    Article  Google Scholar 

  11. WANG Jia-hui, CHEN Zhao-jun, DU Hui, et al. NaOH-KOH capillary action enhances the pyrolysis and debromination of waste printed circuit boards [J]. ACS Sustainable Chemistry & Engineering, 2021, 9(50): 17164–17173. DOI: https://doi.org/10.1021/acssuschemeng.1c06962.

    Article  Google Scholar 

  12. WANG Yi, SUN Shui-yu, YANG Fan, et al. Influence of different catalysts on light of pyrolytic oil from WPCB pyrolysis [J]. Journal of Central South University (Science and Technology), 2014, 45: 979–988. DOI: https://doi.org/10.11817/j.issn.1672-7207(2014)03-0979-10. (in Chinese)

    Google Scholar 

  13. EVANGELOPOULOS P, KANTARELIS E, YANG Wei-hong. Experimental investigation of pyrolysis of printed circuit boards for energy and materials recovery under nitrogen and steam atmosphere [J]. Energy Procedia, 2017, 105: 986–991. DOI: https://doi.org/10.1016/j.egypro.2017.03.435.

    Article  Google Scholar 

  14. CHEN Wei-fang, CHEN Yan-jun, SHU Yong-kai, et al. Characterization of solid, liquid and gaseous products from waste printed circuit board pyrolysis [J]. Journal of Cleaner Production, 2021, 313: 127881. DOI: https://doi.org/10.1016/j.jclepro.2021.127881.

    Article  Google Scholar 

  15. GAO Rui-tong, ZHAN Lu, GUO Jie, et al. Research of the thermal decomposition mechanism and pyrolysis pathways from macromonomer to small molecule of waste printed circuit board [J]. Journal of Hazardous Materials, 2020, 383: 121234. DOI: https://doi.org/10.1016/j.jhazmat.2019.121234.

    Article  Google Scholar 

  16. LIU Wei, XU Jia-qi, HAN Jun-wei, et al. Kinetic and mechanism studies on pyrolysis of printed circuit boards in the absence and presence of copper [J]. ACS Sustainable Chemistry & Engineering, 2019, 7(2): 1879–1889. DOI: https://doi.org/10.1021/acssuschemeng.8b03382.

    Article  Google Scholar 

  17. GAO Rui-tong, LIU Bin-yang, ZHAN Lu, et al. Catalytic effect and mechanism of coexisting copper on conversion of organics during pyrolysis of waste printed circuit boards [J]. Journal of Hazardous Materials, 2021, 403: 123465. DOI: https://doi.org/10.1016/j.jhazmat.2020.123465.

    Article  Google Scholar 

  18. LIU Jing-xin, WANG Han-lin, ZHANG Wen-juan, et al. Mechanistic insights into catalysis of in situ iron on pyrolysis of waste printed circuit boards: Comparative study of kinetics, products, and reaction mechanism [J]. Journal of Hazardous Materials, 2022, 431: 128612. DOI: https://doi.org/10.1016/j.jhazmat.2022.128612.

    Article  Google Scholar 

  19. CAO Rui, ZHOU Rui-shi, LIU Yong-qi, et al. Research on the pyrolysis characteristics and mechanisms of waste printed circuit boards at fast and slow heating rates [J]. Waste Management, 2022, 149: 134–145. DOI: https://doi.org/10.1016/j.wasman.2022.06.008.

    Article  Google Scholar 

  20. GAO Rui-tong, XU Zhen-ming. Pyrolysis and utilization of nonmetal materials in waste printed circuit boards: Debromination pyrolysis, temperature-controlled condensation, and synthesis of oil-based resin [J]. Journal of Hazardous Materials, 2019, 364: 1–10. DOI: https://doi.org/10.1016/j.jhazmat.2018.09.096.

    Article  Google Scholar 

  21. STARINK M J. The determination of activation energy from linear heating rate experiments: A comparison of the accuracy of isoconversion methods [J]. Thermochimica Acta, 2003, 404(1–2): 163–176. DOI: https://doi.org/10.1016/S0040-6031(03)00144-8.

    Article  Google Scholar 

  22. BALABANOVICH A I, LUDA M P, OPERTI L. GC/MS identification of pyrolysis products from fire-retardant brominated epoxy resin [J]. Journal of Fire Sciences, 2005, 23(3): 227–245. DOI: https://doi.org/10.1177/0734904105047006.

    Article  Google Scholar 

  23. BOROJOVICH E J C, AIZENSHTAT Z. Thermal behavior of brominated and polybrominated compounds I: Closed vessel conditions [J]. Journal of Analytical and Applied Pyrolysis, 2002, 63(1): 105–128. DOI: https://doi.org/10.1016/S0165-2370(01)00144-9.

    Article  Google Scholar 

  24. QUAN Cui, LI Ai-min, GAO Ning-bo. Thermogravimetric analysis and kinetic study on large particles of printed circuit board wastes [J]. Waste Management, 2009, 29(8): 2353–2360. DOI: https://doi.org/10.1016/j.wasman.2009.03.020.

    Article  Google Scholar 

  25. KAN Yu-jiao, YUE Qin-yan, GAO Bao-yu, et al. Preparation of epoxy resin-based activated carbons from waste printed circuit boards by steam activation [J]. Materials Letters, 2015, 159: 443–446. DOI: https://doi.org/10.1016/j.matlet.2015.07.053.

    Article  Google Scholar 

  26. BARONTINI F, MARSANICH K, PETARCA L, et al. Thermal degradation and decomposition products of electronic boards containing BFRs [J]. Industrial & Engineering Chemistry Research, 2005, 44(12): 4186–4199. DOI: https://doi.org/10.1021/ie048766l.

    Article  Google Scholar 

  27. JIN Yu-qi, TAO Lin, CHI Yong, et al. Conversion of bromine during thermal decomposition of printed circuit boards at high temperature [J]. Journal of Hazardous Materials, 2011, 186(1): 707–712. DOI: https://doi.org/10.1016/j.jhazmat.2010.11.050.

    Article  Google Scholar 

  28. KIM Y M, HAN T U, WATANABE C, et al. Analytical pyrolysis of waste paper laminated phenolic-printed circuit board (PLP-PCB) [J]. Journal of Analytical and Applied Pyrolysis, 2015, 115: 87–95. DOI: https://doi.org/10.1016/j.jaap.2015.06.013.

    Article  Google Scholar 

  29. ALTARAWNEH M, SAEED A, AL-HARAHSHEH M, et al. Thermal decomposition of brominated flame retardants (BFRs): Products and mechanisms [J]. Progress in Energy and Combustion Science, 2019, 70: 212–259. DOI: https://doi.org/10.1016/j.pecs.2018.10.004.

    Article  Google Scholar 

  30. CHEN Ye, YANG Jia-kuan, ZHANG Yi, et al. Kinetic simulation and prediction of pyrolysis process for non-metallic fraction of waste printed circuit boards by discrete distributed activation energy model compared with isoconversional method [J]. Environmental Science and Pollution Research, 2018, 25(4): 3636–3646. DOI: https://doi.org/10.1007/s11356-017-0763-y.

    Article  Google Scholar 

  31. ZHAN Zhi-hua, QIU Ke-qiang. Pyrolysis kinetics and TG-FTIR analysis of waste epoxy printed circuit boards [J]. Journal of Central South University, 2011, 18(2): 331–336. DOI: https://doi.org/10.1007/s11771-011-0700-z.

    Article  Google Scholar 

  32. KIM Y M, KIM S, LEE J Y, et al. Pyrolysis reaction pathways of waste epoxy-printed circuit board [J]. Environmental Engineering Science, 2013, 30(11): 706–712. DOI: https://doi.org/10.1089/ees.2013.0166.

    Article  Google Scholar 

  33. YE Zi-wei, YANG Fan, LIN Wei-xiong, et al. Improvement of pyrolysis oil obtained from co-pyrolysis of WPCBs and compound additive during two stage pyrolysis [J]. Journal of Analytical and Applied Pyrolysis, 2018, 135: 415–421. DOI: https://doi.org/10.1016/j.jaap.2018.06.011.

    Article  Google Scholar 

  34. YE Zi-wei, YANG Fan, QIU Yi-qin, et al. The debrominated and lightweight oil generated from two stage pyrolysis of WPCBs by using compound chemical additives [J]. Process Safety and Environmental Protection, 2018, 116: 654–662. DOI: https://doi.org/10.1016/j.psep.2018.03.025.

    Article  Google Scholar 

  35. GUO Xiao-juan, QIN F G F, YANG Xiao-xi, et al. Study on low-temperature pyrolysis of large-size printed circuit boards [J]. Journal of Analytical and Applied Pyrolysis, 2014, 105: 151–156. DOI: https://doi.org/10.1016/j.jaap.2013.10.014.

    Article  Google Scholar 

  36. CHIANG H L, LO C C, MA Sen-yi. Characteristics of exhaust gas, liquid products, and residues of printed circuit boards using the pyrolysis process [J]. Environmental Science and Pollution Research, 2010, 17(3): 624–633. DOI: https://doi.org/10.1007/s11356-009-0245-y.

    Article  Google Scholar 

  37. MA Chuan, KAMO T. Two-stage catalytic pyrolysis and debromination of printed circuit boards: Effect of zero-valent Fe and Ni metals [J]. Journal of Analytical and Applied Pyrolysis, 2018, 134: 614–620. DOI: https://doi.org/10.1016/j.jaap.2018.08.012.

    Article  Google Scholar 

  38. ZHANG Ying-wen, ZHOU Chun-bao, LIU Yang, et al. Product characteristics and potential energy recovery for microwave assisted pyrolysis of waste printed circuit boards in a continuously operated auger pyrolyser [J]. Energy, 2022, 239: 122383. DOI: https://doi.org/10.1016/j.energy.2021.122383.

    Article  Google Scholar 

  39. HALL W J, WILLIAMS P T. Separation and recovery of materials from scrap printed circuit boards [J]. Resources, Conservation and Recycling, 2007, 51(3): 691–709. DOI: https://doi.org/10.1016/j.resconrec.2006.11.010.

    Article  Google Scholar 

  40. HADI P, XU Meng, LIN C S K, et al. Waste printed circuit board recycling techniques and product utilization [J]. Journal of Hazardous Materials, 2015, 283: 234–243. DOI: https://doi.org/10.1016/j.jhazmat.2014.09.032.

    Article  Google Scholar 

  41. KHANNA R, IKRAM-UL-HAQ M, CAYUMIL R, et al. Novel carbon micro fibers and foams from waste printed circuit boards [J]. Fuel Processing Technology, 2015, 134: 473–479. DOI: https://doi.org/10.1016/j.fuproc.2015.03.004.

    Article  Google Scholar 

  42. RAJAGOPAL R R, ARAVINDA L S, RAJARAO R, et al. Activated carbon derived from non-metallic printed circuit board waste for supercapacitor application [J]. Electrochimica Acta, 2016, 211: 488–498. DOI: https://doi.org/10.1016/j.electacta.2016.06.077.

    Article  Google Scholar 

  43. GUO Jiu-yong, GUO Jie, XU Zhen-ming. Recycling of non-metallic fractions from waste printed circuit boards: A review [J]. Journal of Hazardous Materials, 2009, 168(2–3): 567–590. DOI: https://doi.org/10.1016/j.jhazmat.2009.02.104.

    Article  Google Scholar 

  44. ASIM M, SABA N, JAWAID M, et al. A review on phenolic resin and its composites [J]. Current Analytical Chemistry, 2018, 14(3): 185–197. DOI: https://doi.org/10.2174/1573411013666171003154410.

    Article  Google Scholar 

  45. LIAO Yu-he, KOELEWIJN S F, van den BOSSCHE G, et al. A sustainable wood biorefinery for low-carbon footprint chemicals production [J]. Science, 2020, 367(6484): 1385–1390. DOI: https://doi.org/10.1126/science.aau1567.

    Article  Google Scholar 

  46. LUO Zhong-yang, LU Kong-yu, YANG Yi, et al. Catalytic fast pyrolysis of lignin to produce aromatic hydrocarbons: Optimal conditions and reaction mechanism [J]. RSC Advances, 2019, 9(55): 31960–31968. DOI: https://doi.org/10.1039/c9ra02538c.

    Article  Google Scholar 

  47. JIN Fan-long, LI Xiang, PARK S J. Synthesis and application of epoxy resins: A review [J]. Journal of Industrial and Engineering Chemistry, 2015, 29: 1–11. DOI: https://doi.org/10.1016/j.jiec.2015.03.026.

    Article  Google Scholar 

  48. PILLAI C K S, PRASAD V S, SUDHA J D, et al. Polymeric resins from renewable resources. II. Synthesis and characterization of flame-retardant prepolymers from cardanol [J]. Journal of Applied Polymer Science, 1990, 41(9–10): 2487–2501. DOI: https://doi.org/10.1002/app.1990.070410947.

    Article  Google Scholar 

  49. ANTONY R, PILLAI C K S. Synthesis and thermal characterization of chemically modified phenolic resins [J]. Journal of Applied Polymer Science, 1994, 54(4): 429–438. DOI: https://doi.org/10.1002/app.1994.070540403.

    Article  Google Scholar 

  50. WANG Yi, SUN Shui-yu, YANG Fan, et al. The effects of activated Al2O3 on the recycling of light oil from the catalytic pyrolysis of waste printed circuit boards [J]. Process Safety and Environmental Protection, 2015, 98: 276–284. DOI: https://doi.org/10.1016/j.psep.2015.07.007.

    Article  Google Scholar 

  51. PARK Y K, HAN T U, JEONG J, et al. Debrominated high quality oil production by the two-step catalytic pyrolysis of phenolic printed circuit boards (PPCB) using natural clays and HY [J]. Journal of Hazardous Materials, 2019, 367: 50–58. DOI: https://doi.org/10.1016/j.jhazmat.2018.12.040.

    Article  Google Scholar 

  52. WICHMANN H, DETTMER F T, BAHADIR M. Thermal formation of PBDD/F from tetrabromobisphenol A-a comparison of polymer linked TBBP A with its additive incorporation in thermoplastics [J]. Chemosphere, 2002, 47(4): 349–355. DOI: https://doi.org/10.1016/S0045-6535(01)00315-0.

    Article  Google Scholar 

  53. CZERNIK S, BRIDGWATER A V. Overview of applications of biomass fast pyrolysis oil [J]. Energy & Fuels, 2004, 18(2): 590–598. DOI: https://doi.org/10.1021/ef034067u.

    Article  Google Scholar 

  54. GAO Rui-tong, LIU Ya, XU Zhen-ming. Synthesis of oil-based resin using pyrolysis oil produced by debromination pyrolysis of waste printed circuit boards [J]. Journal of Cleaner Production, 2018, 203: 645–654. DOI: https://doi.org/10.1016/j.jclepro.2018.08.228.

    Article  Google Scholar 

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Authors and Affiliations

  1. School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China

    Jia-qi Xu  (许佳琦), Wei Liu  (刘维), Fen Jiao  (焦芬), Jun-wei Han  (韩俊伟), Wen-qing Qin  (覃文庆) & Can Cai  (蔡灿)

  2. Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources, Central South University, Changsha, 410083, China

    Jia-qi Xu  (许佳琦), Wei Liu  (刘维), Fen Jiao  (焦芬), Jun-wei Han  (韩俊伟), Wen-qing Qin  (覃文庆) & Can Cai  (蔡灿)

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  1. Jia-qi Xu  (许佳琦)
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Contributions

XU Jia-qi provided investigation, methodology, visualization and writing-original draft preparation. LIU Wei provided supervision, funding acquisition and writing-reviewing and editing. JIAO Fen provided supervision and validation. HAN Jun-wei provided supervision and validation. QIN Wen-qing provided conceptualization and supervision. CAI Can provided data curation.

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Correspondence to Wei Liu  (刘维) or Fen Jiao  (焦芬).

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XU Jia-qi, LIU Wei, JIAO Fen, HAN Jun-wei, QIN Wen-qing, CAI Can declare that they have no conflict of interest.

Foundation item: Project(2018YFC1902505) supported by the National Key R&D Program of China

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Xu, Jq., Liu, W., Jiao, F. et al. Pyrolysis characteristics of waste printed circuit boards and distribution pattern of their valuable liquid products. J. Cent. South Univ. 30, 1523–1538 (2023). https://doi.org/10.1007/s11771-023-5330-8

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