IDEAS home Printed from https://ideas.repec.org/a/gam/jsusta/v17y2025i11p4750-d1661515.html
   My bibliography  Save this article

Harnessing High-Density-Polyethylene-Derived Liquid as a Model Solvent for the Co-Liquefaction of Low-Rank Coals: Toward Sustainable Mesophase Pitch for Making High-Quality Carbon Fibers from Waste Plastics

Author

Listed:
  • Wenjia Wang

    (Department of Chemical Engineering, The University of Utah, Salt Lake City, UT 84112, USA)

  • Adam Gallacher

    (Department of Chemical Engineering, The University of Utah, Salt Lake City, UT 84112, USA)

  • Karissa Jolley

    (Department of Chemical Engineering, The University of Utah, Salt Lake City, UT 84112, USA)

  • Mitchell G. Nelson

    (Department of Chemical Engineering, The University of Utah, Salt Lake City, UT 84112, USA)

  • Eric Eddings

    (Department of Chemical Engineering, The University of Utah, Salt Lake City, UT 84112, USA)

Abstract

The accumulation of polyolefin waste, particularly high-density polyethylene (HDPE), presents a growing environmental challenge due to limited recycling options and poor end-of-life recovery. This study explores a strategy to convert HDPE into mesophase pitch (MP), a valuable carbon precursor, by integrating polyolefin recycling with the mild solvolysis liquefaction (MSL) of low-rank coals. HDPE was first hydrogenolyzed into a hydrogen-rich aromatic liquid (HDPE-liquid), which was then used as the liquefaction solvent. Under identical conditions (400 °C, 60 min), Utah Sufco coal co-liquefied with HDPE-liquid produced tar that formed mesophase pitch with a higher mesophase content (84.5% vs. 78.6%) and a lower softening point (~302 °C vs. >350 °C) compared to pitch from conventional tetralin (THN). The approach was extended to Illinois #6 and Powder River Basin coals, increasing the mesophase content from 12.4% to 32.6% and 17.8% to 62.1%, respectively. These improvements are attributed to differences in tar composition: HDPE-derived tars had lower terminal methyl (Hγ) contents, reducing cross-linking during thermal upgrading. This work demonstrates that HDPE-derived liquids can act as functional solvents for coal liquefaction, enabling an effective route to recycle polyolefin waste into durable carbon products, while also reducing reliance on fossil-based solvents for mesophase pitch production.

Suggested Citation

  • Wenjia Wang & Adam Gallacher & Karissa Jolley & Mitchell G. Nelson & Eric Eddings, 2025. "Harnessing High-Density-Polyethylene-Derived Liquid as a Model Solvent for the Co-Liquefaction of Low-Rank Coals: Toward Sustainable Mesophase Pitch for Making High-Quality Carbon Fibers from Waste Pl," Sustainability, MDPI, vol. 17(11), pages 1-18, May.
    • Handle: RePEc:gam:jsusta:v:17:y:2025:i:11:p:4750-:d:1661515
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/2071-1050/17/11/4750/pdf
    Download Restriction: no
    File URL: https://www.mdpi.com/2071-1050/17/11/4750/
    Download Restriction: no
    ---><---

    References listed on IDEAS

    as
    1. Ken K. Robinson, 2009. "Reaction Engineering of Direct Coal Liquefaction," Energies, MDPI, vol. 2(4), pages 1-31, October.
    2. Hengfu Shui & Zhenyi Cai & Chunbao Xu, 2010. "Recent Advances in Direct Coal Liquefaction," Energies, MDPI, vol. 3(2), pages 1-16, January.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Moinuddin Ghauri & Khurram Shahzad & Abrar Inayat & Zulfiqar Ali & Keith R. Cliffe, 2016. "High Pressure Oxydesulphurisation of Coal Using KMnO 4 —Effect of Coal Slurry Concentration, pH and Alkali," Energies, MDPI, vol. 9(4), pages 1-14, April.
    2. Moinuddin Ghauri & Abrar Inayat & Muhammad Tariq Bashir & Salmiaton B. Ali & Keith R. Cliffe, 2013. "High Pressure Oxydesulphurisation of Coal—A Parametric Study," Energies, MDPI, vol. 6(4), pages 1-14, April.
    3. Ail, Snehesh Shivananda & Dasappa, S., 2016. "Biomass to liquid transportation fuel via Fischer Tropsch synthesis – Technology review and current scenario," Renewable and Sustainable Energy Reviews, Elsevier, vol. 58(C), pages 267-286.
    4. Moinuddin Ghauri & Khurram Shahzad & Abrar Inayat & Zulfiqar Ali & Waqar Ali Khan & Javaid Akhtar & Keith R. Cliffe, 2016. "High Pressure Oxydesulphurisation of Coal—Effect of Oxidizing Agent, Solvent, Shear and Agitator Configuration," Energies, MDPI, vol. 9(7), pages 1-15, June.
    5. Jiang, Yuan & Bhattacharyya, Debangsu, 2017. "Techno-economic analysis of direct coal-biomass to liquids (CBTL) plants with shale gas utilization and CO2 capture and storage (CCS)," Applied Energy, Elsevier, vol. 189(C), pages 433-448.
    6. Jiang, Yuan & Bhattacharyya, Debangsu, 2016. "Process modeling of direct coal-biomass to liquids (CBTL) plants with shale gas utilization and CO2 capture and storage (CCS)," Applied Energy, Elsevier, vol. 183(C), pages 1616-1632.
    7. Mushtaq, Faisal & Mat, Ramli & Ani, Farid Nasir, 2014. "A review on microwave assisted pyrolysis of coal and biomass for fuel production," Renewable and Sustainable Energy Reviews, Elsevier, vol. 39(C), pages 555-574.
    8. Galina Nyashina & Jean Claude Legros & Pavel Strizhak, 2017. "Environmental Potential of Using Coal-Processing Waste as the Primary and Secondary Fuel for Energy Providers," Energies, MDPI, vol. 10(3), pages 1-11, March.
    9. Alla Krylova & Kristina Krysanova & Mayya Kulikova & Albert Kulikov, 2021. "Non-Catalytic Dissolution of Biochar Obtained by Hydrothermal Carbonization of Sawdust in Hydrogen Donor Solvent," Energies, MDPI, vol. 14(18), pages 1-20, September.
    10. Shui, Hengfu & Shan, Chuanjun & Cai, Zhengyi & Wang, Zhicai & Lei, Zhiping & Ren, Shibiao & Pan, Chunxiu & Li, Haiping, 2011. "Co-liquefaction behavior of a sub-bituminous coal and sawdust," Energy, Elsevier, vol. 36(11), pages 6645-6650.
    11. Roman Volkov & Timur Valiullin & Olga Vysokomornaya, 2021. "Spraying of Composite Liquid Fuels Based on Types of Coal Preparation Waste: Current Problems and Achievements: Review," Energies, MDPI, vol. 14(21), pages 1-17, November.
    12. Yizhao Li & Yali Cao & Dianzeng Jia, 2017. "Direct Coal Liquefaction with Fe 3 O 4 Nanocatalysts Prepared by a Simple Solid-State Method," Energies, MDPI, vol. 10(7), pages 1-7, July.
    13. Engin Kocaturk & Tufan Salan & Orhan Ozcelik & Mehmet Hakkı Alma & Zeki Candan, 2023. "Recent Advances in Lignin-Based Biofuel Production," Energies, MDPI, vol. 16(8), pages 1-17, April.
    14. Kong, Hui & Kong, Xianghui & Wang, Jian & Zhang, Jun, 2019. "Thermodynamic analysis of a solar thermochemical cycle-based direct coal liquefaction system for oil production," Energy, Elsevier, vol. 179(C), pages 1279-1287.
    15. Hengfu Shui & Zhenyi Cai & Chunbao Xu, 2010. "Recent Advances in Direct Coal Liquefaction," Energies, MDPI, vol. 3(2), pages 1-16, January.
    16. Liu, Fang-Jing & Wei, Xian-Yong & Fan, Maohong & Zong, Zhi-Min, 2016. "Separation and structural characterization of the value-added chemicals from mild degradation of lignites: A review," Applied Energy, Elsevier, vol. 170(C), pages 415-436.

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:gam:jsusta:v:17:y:2025:i:11:p:4750-:d:1661515. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: MDPI Indexing Manager (email available below). General contact details of provider: https://www.mdpi.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.