Investigating the Pyrolysis Process of Polyethylene in the Presence of Biochar Catalyst to Convert iT into Liquid Fuel

Document Type : Research Article


Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, I.R. IRAN


In this study, the effect of biochar catalyst on the pyrolysis process of light (LDPE), heavy (HDPE), and mixed polyethylene was investigated. For this aim, 30 grams of sample was loaded in a laboratory-sized reactor and pyrolyzed at 500°C under atmospheric pressure. The amount of gas produced in the presence of catalysts decreased 11.96 and 16.08 wt% for HDPE and mixed polyethylene, but not for LDPE, indicating an increase in heavy vapor cracking. The amount of wax produced in the presence of a catalyst has increased 5.94 and 3.59 wt% for HDPE and mixed polyethylene excluding LDPE. The amount of liquid product obtained was increased for all three samples in the presence of biochar catalysts (from 12.30 to 16.69, from 38.21 to 46.19, and from 4.47 to 16.97 wt% for LDPE, HDPE, and mixed, respectively). Biochar increased the propane content for all three samples. This was due to the increase in cracking and conversion of heavy molecules to propane. Ethane content for LDPE decreased while for HDPE increased. This is indicating more breakdown of HDPE molecules and reaction of molecules with each other and with ethane to other products such as propane. Liquid product analysis showed that biochar catalysts tended to reduce compounds such as alcohols, indicating a tendency to deoxidize. In addition, biochar also caused the breakdown of larger and smaller aromatic molecules. The catalyst analysis indicated the presence of a coke layer on the catalyst, which contained more aromatic and oxygenated compounds.


Main Subjects

[1] McKay G., Dioxin Characterisation, Formation and Minimisation During Municipal Solid Waste (MSW) Incineration. Chemical Engineering Journal, 86(3): 343-68 (2002).
[2] Li Q., Meng A., Jia J., Zhang Y., Investigation of Heavy Metal Partitioning Influenced by Flue Gas Moisture and Chlorine Content During Waste Incineration, Journal of Environmental Sciences, 22(5): 760-8. (2010).
[3] Ahmad I., Khan M.I., Ishaq M., Khan H., Gul K., Ahmad W., Catalytic Efficiency of Some Novel Nanostructured Heterogeneous Solid Catalysts in Pyrolysis of HDPE, Polymer Degradation and Stability, 98(12): 2512-9 (2013).
[4] Zhou H., Meng A., Long Y., Li Q., Zhang Y., An Overview of Characteristics of Municipal Solid Waste Fuel in China: Physical, Chemical Composition and Heating Value, Renewable and Sustainable Energy Reviews, 36: 107-122 (2014).
[5] He M., Mourant D., Gunawan R., Lievens C., Wang X.S., Ling K., Bartle J., Li C.Z., Yield and Properties of Bio-Oil from the Pyrolysis of Mallee Leaves in a Fluidised-Bed Reactor, Fuel, 102: 506-513 (2012).
[6] Drożdżek M., Zawadzki J., Zielenkiewicz T., Kłosińska T., Gawron J., Gołofit T., Borysiak S., The Influence of Method of Cellulose Isolation from Wood on the Degree and Index of Crystallinity, Wood Research, 60(2): 255-262 (2015).
[7] Wang L., Dibdiakova J., Characterization of Ashes from Different Wood Parts of Norway Spruce Tree, Chemical Engineering Transactions, 37: 37-42 (2014).
[8] Serafimova E., Mladenov M., Mihailova I., Pelovski Y., Study on the Characteristics of Waste Wood Ash, Journal of the University of Chemical Technology and Metallurgy, 46(1): 31-34 (2011).
[9] Gholizadeh M., Gunawan R., Hu X., Kadarwati S., Westerhof R., Chaiwat W., Hasan MM., Li C.Z., Importance of Hydrogen and Bio-Oil Inlet Temperature during the Hydrotreatment of Bio-Oil, Fuel Processing Technology, 150: 132-140 (2016).
[10] Gholizadeh M., Gunawan R., Hu X., Hasan M.M., Kersten S., Westerhof R., Chaitwat W., Li C.Z., Different Reaction Behaviours of the Light and Heavy Components of Bio-Oil During the Hydrotreatment in a Continuous Pack-Bed Reactor, Fuel Processing Technology, 146: 76-84 (2016).
[11] Gholizadeh M., Gunawan R., Hu X., de Miguel Mercader F., Westerhof R., Chaitwat W., Hasan M.M., Mourant D., Li C.Z., Effects of Temperature on the Hydrotreatment Behaviour of Pyrolysis Bio-Oil and Coke Formation in a Continuous Hydrotreatment Reactor, Fuel Processing Technology, 148: 175-183 (2016).
[12] Tessini C., Romero R., Escobar M., Gordon A., Flores M., Development of an Analytical Method for the Main Organic Compounds Derived from Thermochemical Conversion of Biomass, Journal of the Chilean Chemical Society, 61(1): 2837-42 (2016).
[13] Choi Y.S., Johnston P.A., Brown R.C., Shanks B.H., Lee K.H., Detailed Characterization of Red Oak-Derived Pyrolysis Oil: Integrated Use of GC, HPLC, IC, GPC and Karl-Fischer, Journal of Analytical and Applied Pyrolysis, 110: 147-154 (2014).
[14] Mullen C.A., Boateng A.A., Chemical Composition of Bio-Oils Produced by Fast Pyrolysis of Two Energy Crops, Energy & Fuels, 22(3): 2104-9 (2008).
[15] Shirvani S., Ghashghaee M., Kegnæs S., Dual Role of Ferric Chloride in Modification of USY Catalyst for Enhanced Olefin Production from Refinery Fuel Oil, Applied Catalysis A: General, 580: 131-139 (2019).
[16] شیروانی س.، قشقائی م.، قمبریان م.، پیرولیز دو مرحله‌ای نفت کوره پالایشگاهی به اولفین‌ها و سوخت، نشریه شیمی و مهندسی شیمی ایران، (4)38: 243 تا 252 (1398).
[17] Ghashghaee M., Shirvani S., Kegnæs S., Steam Catalytic Cracking of Fuel Oil Over a Novel Composite Nanocatalyst: Characterization, Kinetics and Comparative Perspective, J. Anal. Appl. Pyrol., 138: 281-293 (2019).
[18] Ghashghaee M., Shirvani S., Ghambarian M., Kegnæs S., Synergistic Coconversion of Refinery Fuel Oil and Methanol over H-ZSM-5 Catalyst for Enhanced Production of Light Olefins, Energy Fuels, 33(6): 5761−5765 (2019).
[19] Ghashghaee M., Shirvani S., Ghambarian M., Eidi A., Two-Stage Thermocatalytic Upgrading of Fuel Oil to Olefins and Fuels Over a Nanoporous Hierarchical Acidic Catalyst, Pet. Sci. Technol., 37(16): 1910–1916 (2019).
[20] Shirvani S., Ghashghaee M., Combined Effect of Nanoporous Diluent and Steam on Catalytic Upgrading of Fuel Oil to Olefins and Fuels Over USY Catalyst, Petrol. Sci. Technol., 36(11): 750–755 (2018).
[21] Ghashghaee M., Shirvani S., Two-Step Thermal Cracking of an Extra-Heavy Fuel Oil: Experimental Evaluation, Characterization, and Kinetics, Ind. Eng. Chem. Res., 57(22): 7421–7430 (2018).
[22] Ghashghaee M., Omidkhah M.R., Shirvani S., “Catalytic Degradation of Linear Low-Density Polyethylene over USY Catalyst: Effect of Catalyst-to-Polymer Ratio”, 13th International Seminar on Polymer Science and Technology (ISPST 2018), Tehran, Iran, 19–22 November (2018).
[23] Wang Y., Li X., Mourant D., Gunawan R., Zhang S., Li C.Z., Formation of Aromatic Structures during the Pyrolysis of Bio-Oil, Energy & Fuels, 26(1): 241-7 (2011).
[24] Garcia-Perez M., Wang X.S., Shen J., Rhodes M.J., Tian F., Lee W.J., Wu H., Li C.Z., Fast Pyrolysis of Oil Mallee Woody Biomass: Effect of Temperature on the Yield and Quality of Pyrolysis Products, Industrial & Engineering Chemistry Research, 47(6): 1846-54 (2008).
[25] Garcia-Perez M., Chaala A., Pakdel H., Kretschmer D., Roy C., Characterization of Bio-Oils in Chemical Families, Biomass and Bioenergy, 31(4): 222-242 (2007).
[26] Garcia-Perez M., Wang S., Shen J., Rhodes M., Lee W.J., Li C.Z., Effects of Temperature on the Formation of Lignin-Derived Oligomers During the Fast Pyrolysis of Mallee Woody Biomass, Energy & Fuels, 22(3): 2022-2032 (2008).
[27] Prabir B., "Biomass Gasification and Pyrolysis", Elsevier, The Boulevard, Langford Lane, Kidlington, Oxford, OX5 1GB, UK. (2010).
[28] Alcock C.B., “Thermochemical Processes”, First Edition, University of Norte Dame, Indiana, USA (2000).
[29] Gašparovič L., Koreňová Z., Jelemenský Ľ., Kinetic Study of Wood Chips Decomposition by TGA, Chemical Papers, 64(2): 174-81 (2010).
[30] Scott DS., Piskorz J., Radlein D., Liquid Products from the Continuous Flash Pyrolysis of Biomass, Industrial & Engineering Chemistry Process Design and Development, 24(3): 581-8 (1985).
[31] Fagbemi L., Khezami L., Capart R., Pyrolysis Products from Different Biomasses: Application to the Thermal Cracking of Tar, Applied Energy, 69(4): 293-306 (2001).
[32] Mohan D., Pittman Jr C.U., Steele P.H., Pyrolysis of Wood/Biomass for Bio-Oil: A Critical Review, Energy & Fuels, 20(3): 848-889 (2006).
[33] Onay O., Kockar O.M., Slow, Fast and Flash Pyrolysis of Rapeseed, Renewable Energy, 28(15): 2417-2433 (2003).
[34] Al Arni S., Comparison of Slow and Fast Pyrolysis for Converting Biomass into Fuel, Renewable Energy, 124: 197-201 (2018).
[35] Pattiya A., “Fast Pyrolysis, InDirect Thermochemical Liquefaction for Energy Applications”, Woodhead Publishing, 1: 3-28 (2018).
[36] Data Excerpted from Bridgwater. Compiled from Data in Demirbas (2001).
[37] Brown R.C., Wang K., “Fast Pyrolysis of Biomass: Advances in Science and Technology”, Royal Society of Chemistry, (2017).
[38] Liang C., Wang Y., Jiang S., Zhang Q., Li X., The Comprehensive Study on Hydrocarbon Fuel Pyrolysis and Heat Transfer Characteristics, Applied Thermal Engineering, 117: 652-8 (2017).
[39] Liu Z., Zhang F., Yan S., Tian L., Wang H., Liu H., Wang H., Hu J., Effects of Temperature and Low-Concentration Oxygen on Pine Wood Sawdust Briquettes Pyrolysis: Gas Yields and Biochar Briquettes Physical Properties, Fuel Processing Technology, 177: 228-36 (2018).
[40] Staurt B., “Infrared Spectroscopy: Fundamentals and Applications”, John Wiley and Sons Inc, West Sussex, England (2004).
[41] Iglesias M.J., Jimenez A., Laggoun-Défarge F., Suarez-Ruiz I., FTIR Study of Pure Vitrains and Associated Coals, Energy & Fuels, 9(3): 458-66 (1995).
[42] Krull E.S., Baldock J., Skjemstad J.O., Smernik R.S., “Characteristic of Biochar: Organo-Chemical Properties, Biochar for Environment Science and Technology”, Earthsan Publication Ltd, 4: 53-66 (2009).