Deactivation and Regeneration of HZSM-5 during Aromatization of Oil Shale Pyrolysis Vapors: From Coke Nature to Overall Catalyst Performance
DOI:
https://doi.org/10.66960/jof.3093-8899.00042Keywords:
HZSM-5, deactivation, coke, regeneration, pyrolysis vapors, monoaromatic hydrocarbons, TPO, integrated productivityAbstract
A critical review of the mechanisms of HZSM-5 deactivation and regeneration is presented with specific reference to the two-stage aromatization of shale pyrolysis vapors. It is demonstrated that evaluating a catalyst based on a single fresh cycle systematically overestimates the technological value of materials with high initial acidity when this acidity is accompanied by rapid micropore blockage and an increase in polyaromatic coke formation.
A multilevel catalyst-state model is proposed that integrates coke amount, coke localization, degree of condensation, loss of micropore volume, changes in accessible Brønsted/Lewis acidity, and structural recovery following oxidative regeneration. For cyclic pyrolysis, the principle of correcting for temporal variability in the composition of the feed vapors is adapted: catalyst activity should be compared at an equivalent cumulative vapor load or against a parallel control sample of the fresh catalyst.
As the primary performance indicator, the integrated productivity Σm(MAH)/m_cat,0 over a series of reaction–regeneration cycles is proposed, complemented by the activity recovery coefficient and specific coke formation. Based on the literature concerning shale, pyrolysis oils, and other complex hydrocarbon streams, a research program comprising at least five cycles is formulated. The program includes characterization of fresh, spent, and regenerated HZSM-5 using XRD, N₂ adsorption, NH₃-TPD/pyridine-FTIR, and TGA/TPO. Raman spectroscopy is proposed as an independent method for evaluating the degree of ordering of carbonaceous deposits.
The scientific contribution of this review lies in shifting from the static concept of “catalyst activity” toward a measurable catalyst-state map and cumulative productivity, as well as in establishing a practical regeneration window bounded, on one side, by incomplete coke removal and, on the other, by irreversible dealumination and loss of acidity.
References
Williams P.T., Chishti H.M. Influence of residence time and catalyst regeneration on the pyrolysis–zeolite catalysis of oil shale. Journal of Analytical and Applied Pyrolysis. 2001;60(2):187–203. DOI: 10.1016/S0165-2370(00)00198-4. DOI: https://doi.org/10.1016/S0165-2370(00)00198-4
Chang Z. et al. Production of aromatic hydrocarbons from catalytic pyrolysis of Huadian oil shale using ZSM-5 zeolites as catalyst. Journal of Analytical and Applied Pyrolysis. 2021;159:104990. DOI: 10.1016/j.jaap.2020.104990. DOI: https://doi.org/10.1016/j.jaap.2020.104990
Yang Q. et al. Continuous catalytic pyrolysis of waste oil to aromatics: Exploring the structure-performance relations of ZSM-5 based on different scale-up forms. Chemical Engineering Journal. 2023;475:146259. DOI: 10.1016/j.cej.2023.146259. DOI: https://doi.org/10.1016/j.cej.2023.146259
Nyembe N., Isa Y.M. Design rules for hierarchical ZSM-5 zeolites in catalytic fast pyrolysis: Linking porosity and acidity to selectivity and deactivation resistance. Chemical Engineering and Processing - Process Intensification. 2026;227:110940. DOI: 10.1016/j.cep.2026.110940. DOI: https://doi.org/10.1016/j.cep.2026.110940
Bensafi B., Chouat N., Djafri F. The universal zeolite ZSM-5: Structure and synthesis strategies. A review. Coordination Chemistry Reviews. 2023;496:215397. DOI: 10.1016/j.ccr.2023.215397. DOI: https://doi.org/10.1016/j.ccr.2023.215397
Lok C.M., Van Doorn J., Aranda Almansa G. Promoted ZSM-5 catalysts for the production of bio-aromatics, a review. Renewable and Sustainable Energy Reviews. 2019;113:109248. DOI: 10.1016/j.rser.2019.109248. DOI: https://doi.org/10.1016/j.rser.2019.109248
Daligaux V., Richard R., Manero M.-H. Deactivation and regeneration of zeolite catalysts used in pyrolysis of plastic wastes—A process and analytical review. Catalysts. 2021;11(7):770. DOI: 10.3390/catal11070770. DOI: https://doi.org/10.3390/catal11070770
Argyle M.D., Bartholomew C.H. Heterogeneous catalyst deactivation and regeneration: A review. Catalysts. 2015;5:145–269. DOI: 10.3390/catal5010145. DOI: https://doi.org/10.3390/catal5010145
Guisnet M., Magnoux P. Deactivation by coking of zeolite catalysts. Prevention of deactivation. Optimal conditions for regeneration. Catalysis Today. 1997;36:477–483. DOI: 10.1016/S0920-5861(96)00238-6. DOI: https://doi.org/10.1016/S0920-5861(96)00238-6
Guisnet M., Magnoux P. Organic chemistry of coke formation. Applied Catalysis A: General. 2001;212:83–96. DOI: 10.1016/S0926-860X(00)00845-0. DOI: https://doi.org/10.1016/S0926-860X(00)00845-0
Fals J. et al. Deactivation and regeneration dynamics in hierarchical zeolites: Coke characterization and impact on catalytic cracking of vacuum gas oil. Heliyon. 2024;10:e37813. DOI: 10.1016/j.heliyon.2024.e37813. DOI: https://doi.org/10.1016/j.heliyon.2024.e37813
Chen T.-S., Wang P.-F., Du Z.-Y., Liao Y.-H. Comparative effects of mesopores and framework defects on the deactivation of HZSM-5 catalyst during alkylphenol dealkylation. Chemical Engineering Science. 2023;275:118712. DOI: 10.1016/j.ces.2023.118712. DOI: https://doi.org/10.1016/j.ces.2023.118712
Anekwe I.M.S. et al. Stability, deactivation and regeneration study of a newly developed HZSM-5 and Ni-doped HZSM-5 zeolite catalysts for ethanol-to-hydrocarbon conversion. Catalysis Communications. 2024;186:106802. DOI: 10.1016/j.catcom.2023.106802. DOI: https://doi.org/10.1016/j.catcom.2023.106802
Liu X. et al. Catalytic pyrolysis of nonedible oils for the production of renewable aromatics using metal-modified HZSM-5 catalysts. ACS Omega. 2022;7:18953–18968. DOI: 10.1021/acsomega.2c02011. DOI: https://doi.org/10.1021/acsomega.2c02011
Wang J. et al. Aromatic hydrocarbon production and catalyst regeneration in pyrolysis of oily sludge using ZSM-5 zeolites as catalysts. Energy & Fuels. 2017;31:11681–11689. DOI: 10.1021/acs.energyfuels.7b01855. DOI: https://doi.org/10.1021/acs.energyfuels.7b01855
Kariim I., Swai H., Kivevele T. Bio-oil upgrading over ZSM-5 catalyst: A review of catalyst performance and deactivation. International Journal of Energy Research. 2023;2023:4776962. DOI: 10.1155/2023/4776962. DOI: https://doi.org/10.1155/2023/4776962
Li Y. et al. ZSM-5 zeolite for catalytic cracking of non-edible oil: Strategies for coke suppression. Catalysts. 2026;16:834. DOI: 10.3390/catal16090834. DOI: https://doi.org/10.3390/catal16090834
He L. et al. Mechanisms of sulfur and nitrogen transformation during Longkou oil shale pyrolysis. Energy. 2021;232:120977. DOI: 10.1016/j.energy.2021.120977. DOI: https://doi.org/10.1016/j.energy.2021.120977
Yung M.M. et al. Restoring ZSM-5 performance for catalytic fast pyrolysis of biomass: Effect of regeneration temperature. Catalysis Today. 2019;323:76–85. DOI: 10.1016/j.cattod.2018.06.025. DOI: https://doi.org/10.1016/j.cattod.2018.06.025
Heracleous E. et al. Characterization of deactivated and regenerated zeolite ZSM-5-based catalyst extrudates used in catalytic pyrolysis of biomass. Journal of Catalysis. 2019;380:108–122. DOI: 10.1016/j.jcat.2019.10.019. DOI: https://doi.org/10.1016/j.jcat.2019.10.019
Luna-Murillo B. et al. Catalytic fast pyrolysis of biomass: Catalyst characterization reveals the feed-dependent deactivation of a technical ZSM-5-based catalyst. ACS Sustainable Chemistry & Engineering. 2021;9(1):291–304. DOI: 10.1021/acssuschemeng.0c07153. DOI: https://doi.org/10.1021/acssuschemeng.0c07153
Stanton A.R., Iisa K., Mukarakate C., Nimlos M.R. Role of biopolymers in the deactivation of ZSM-5 during catalytic fast pyrolysis of biomass. ACS Sustainable Chemistry & Engineering. 2018;6(8):10030–10038. DOI: 10.1021/acssuschemeng.8b01333. DOI: https://doi.org/10.1021/acssuschemeng.8b01333
Eschenbacher A. et al. Impact of ZSM-5 deactivation on bio-oil quality during upgrading of straw-derived pyrolysis vapors. Energy & Fuels. 2019;33(1):397–412. DOI: 10.1021/acs.energyfuels.8b03691. DOI: https://doi.org/10.1021/acs.energyfuels.8b03691
Kalogiannis K.G., Stefanidis S.D., Lappas A.A. Catalyst deactivation, ash accumulation and bio-oil deoxygenation during ex situ catalytic fast pyrolysis of biomass in a cascade thermal-catalytic reactor system. Fuel Processing Technology. 2019;186:99–109. DOI: 10.1016/j.fuproc.2018.12.008. DOI: https://doi.org/10.1016/j.fuproc.2018.12.008
Hernández-Giménez A.M. et al. Deactivation and regeneration of solid acid and base catalyst bodies used in cascade for bio-oil synthesis and upgrading. Journal of Catalysis. 2022;405:641–651. DOI: 10.1016/j.jcat.2021.09.029. DOI: https://doi.org/10.1016/j.jcat.2021.09.029
Vitolo S., Bresci B., Seggiani M., Gallo M.G. Catalytic upgrading of pyrolytic oils over HZSM-5 zeolite: behaviour of the catalyst when used in repeated upgrading–regenerating cycles. Fuel. 2001;80(1):17–26. DOI: 10.1016/S0016-2361(00)00063-6. DOI: https://doi.org/10.1016/S0016-2361(00)00063-6
Li Y. et al. Control of coke deposition in solid acid catalysis through the doping of transition metal combined with the assistance of H2: a review. Applied Catalysis A: General. 2021;626:118340. DOI: 10.1016/j.apcata.2021.118340. DOI: https://doi.org/10.1016/j.apcata.2021.118340
Yao N.-Y. et al. Coke formation on different metal-modified (Co, Mo and Zr) ZSM-5 in the catalytic pyrolysis of cellulose to light aromatics. Journal of Analytical and Applied Pyrolysis. 2024;179:106516. DOI: 10.1016/j.jaap.2024.106516. DOI: https://doi.org/10.1016/j.jaap.2024.106516
Hu J. et al. Synthesis of HZSM-5@activated carbon for improving aromatic production from catalytic pyrolysis of biomass. Chemical Engineering Journal. 2024;494:153031. DOI: 10.1016/j.cej.2024.153031. DOI: https://doi.org/10.1016/j.cej.2024.153031
Zhong S. et al. Selective production of aromatics from catalytic fast pyrolysis of cassava residues over vanadium modified ZSM-5: Experimental and kinetic study. Journal of Analytical and Applied Pyrolysis. 2024;177:106334. DOI: 10.1016/j.jaap.2023.106334. DOI: https://doi.org/10.1016/j.jaap.2023.106334
Qiao J. et al. Methanol to aromatics: isolated zinc phosphate groups on HZSM-5 zeolite enhance BTX selectivity and catalytic stability. RSC Advances. 2020;10:5961–5971. DOI: 10.1039/C9RA09657D. DOI: https://doi.org/10.1039/C9RA09657D
Shim H., Hong J., Ha K.-S. Efficient utilization of hydrocarbon mixture to produce aromatics over Zn/ZSM-5 and physically mixed with ZSM-5. Catalysts. 2022;12(5):501. DOI: 10.3390/catal12050501. DOI: https://doi.org/10.3390/catal12050501
Wang W., Luo Z., Li S., Xue S., Sun H. Novel micro-mesoporous composite ZSM-5 catalyst for aromatics production by catalytic fast pyrolysis of lignin residues. Catalysts. 2020;10(4):378. DOI: 10.3390/catal10040378. DOI: https://doi.org/10.3390/catal10040378
Chen H. et al. Catalytic fast pyrolysis of rice straw to aromatic compounds over hierarchical HZSM-5 produced by alkali treatment and metal-modification. Journal of Analytical and Applied Pyrolysis. 2018;131:76–84. DOI: 10.1016/j.jaap.2018.02.009. DOI: https://doi.org/10.1016/j.jaap.2018.02.009
Hernández-Giménez A.M. et al. Effect of mesoporosity, acidity and crystal size of zeolite ZSM-5 on catalytic performance during the ex-situ catalytic fast pyrolysis of biomass. ChemCatChem. 2021;13:1207–1219. DOI: 10.1002/cctc.202001778. DOI: https://doi.org/10.1002/cctc.202001778
Qiao K. et al. Catalytic fast pyrolysis of cellulose in a microreactor system using hierarchical ZSM-5 zeolites treated with various alkalis. Applied Catalysis A: General. 2017;547:274–282. DOI: 10.1016/j.apcata.2017.07.034. DOI: https://doi.org/10.1016/j.apcata.2017.07.034
Jia L.Y. et al. Catalytic fast pyrolysis of biomass: superior selectivity of hierarchical zeolites to aromatics. Green Chemistry. 2017;19:5442–5459. DOI: 10.1039/C7GC02309J. DOI: https://doi.org/10.1039/C7GC02309J
Chen H. et al. Controlled synthesis of hierarchical ZSM-5 for catalytic fast pyrolysis of cellulose to aromatics. Journal of Materials Chemistry A. 2018;6:21178–21185. DOI: 10.1039/C8TA08930B. DOI: https://doi.org/10.1039/C8TA08930B
Yang K. et al. Preparation of nanocrystalline ZSM-5 and its catalytic performance in fast pyrolysis of cellulose to produce aromatic hydrocarbons. Microporous and Mesoporous Materials. 2022;331:111679. DOI: 10.1016/j.micromeso.2022.111679. DOI: https://doi.org/10.1016/j.micromeso.2022.111679
Sun H. et al. Porosity roles of micro-mesostructured ZSM-5 in catalytic fast pyrolysis of cellulolytic enzyme lignin for aromatics. Energy Conversion and Management. 2021;247:114753. DOI: 10.1016/j.enconman.2021.114753. DOI: https://doi.org/10.1016/j.enconman.2021.114753
Du H. et al. Ex-situ catalytic upgrading of vapors from microwave-assisted pyrolysis of bamboo with chemical liquid deposition modified HZSM-5 to enhance aromatics production. Journal of Analytical and Applied Pyrolysis. 2020;149:104857. DOI: 10.1016/j.jaap.2020.104857. DOI: https://doi.org/10.1016/j.jaap.2020.104857
Dai G. et al. Enhancement of aromatics production from catalytic pyrolysis of biomass over HZSM-5 modified by chemical liquid deposition. Journal of Analytical and Applied Pyrolysis. 2018;134:439–445. DOI: 10.1016/j.jaap.2018.07.010. DOI: https://doi.org/10.1016/j.jaap.2018.07.010
Rahman M.M., Liu R., Cai J. Catalytic fast pyrolysis of biomass over zeolites for high quality bio-oil – a review. Fuel Processing Technology. 2018;180:32–46. DOI: 10.1016/j.fuproc.2018.08.002. DOI: https://doi.org/10.1016/j.fuproc.2018.08.002
Liang J., Shan G., Sun Y. Catalytic fast pyrolysis of lignocellulosic biomass: critical role of zeolite catalysts. Renewable and Sustainable Energy Reviews. 2021;139:110707. DOI: 10.1016/j.rser.2021.110707. DOI: https://doi.org/10.1016/j.rser.2021.110707
Liu R. et al. Multi-scale complexities of solid acid catalysts in the catalytic fast pyrolysis of biomass for bio-oil production – a review. Progress in Energy and Combustion Science. 2020;80:100852. DOI: 10.1016/j.pecs.2020.100852. DOI: https://doi.org/10.1016/j.pecs.2020.100852
Valle B. et al. Selective production of aromatics by crude bio-oil valorization with a nickel-modified HZSM-5 zeolite catalyst. Energy & Fuels. 2010;24:2060–2070. DOI: 10.1021/ef901231j. DOI: https://doi.org/10.1021/ef901231j
Mullen C.A., Boateng A.A. Catalytic pyrolysis-GC/MS of lignin from several sources. Fuel Processing Technology. 2010;91:1446–1458. DOI: 10.1016/j.fuproc.2010.05.022. DOI: https://doi.org/10.1016/j.fuproc.2010.05.022
Zheng Y. et al. Study on aromatics production via the catalytic pyrolysis vapor upgrading of biomass using metal-loaded modified H-ZSM-5. Journal of Analytical and Applied Pyrolysis. 2017;126:169–179. DOI: 10.1016/j.jaap.2017.06.011. DOI: https://doi.org/10.1016/j.jaap.2017.06.011
Carlson T.R. et al. Aromatic production from catalytic fast pyrolysis of biomass-derived feedstocks. Topics in Catalysis. 2009;52:241–252. DOI: 10.1007/s11244-008-9160-6. DOI: https://doi.org/10.1007/s11244-008-9160-6
Yu Y. et al. The role of shape selectivity in catalytic fast pyrolysis of lignin with zeolite catalysts. Applied Catalysis A: General. 2012;447–448:115–123. DOI: 10.1016/j.apcata.2012.09.012. DOI: https://doi.org/10.1016/j.apcata.2012.09.012
Luan P. et al. Ex-situ catalytic fast pyrolysis of waste polycarbonate for aromatic hydrocarbons: Utilizing HZSM-5/modified HZSM-5. Journal of Analytical and Applied Pyrolysis. 2024;182:106667. DOI: 10.1016/j.jaap.2024.106667. DOI: https://doi.org/10.1016/j.jaap.2024.106667
Liu H., Qiu Y., Shan R., Zhang J., Yuan H., Chen Y. Catalytic pyrolysis of polyethylene over bimetallic-modified ZSM-5: Role of alkaline sites on structure regulation, thermal behavior and aromatics production. Fuel. 2025;395:135180. DOI: 10.1016/j.fuel.2025.135180. DOI: https://doi.org/10.1016/j.fuel.2025.135180
Wu Z. et al. Boosting aromatic production from catalytic pyrolysis of polyethylene by co-feeding CO₂ over Zn-modified HZSM-5 zeolite. Journal of the Energy Institute. 2026;127:102602. DOI: 10.1016/j.joei.2026.102602. DOI: https://doi.org/10.1016/j.joei.2026.102602
Gu B. et al. Catalytic fast pyrolysis of sewage sludge over HZSM-5: A study of light aromatics, coke, and nitrogen migration under different atmospheres. Industrial & Engineering Chemistry Research. 2020;59(39):17537–17545. DOI: 10.1021/acs.iecr.0c01170. DOI: https://doi.org/10.1021/acs.iecr.0c01170
Geng R. et al. Structure evolution of Zn species on fresh, deactivated, and regenerated Zn/ZSM-5 catalysts in ethylene aromatization. ACS Catalysis. 2022;12(23):14735–14747. DOI: 10.1021/acscatal.2c04074. DOI: https://doi.org/10.1021/acscatal.2c04074
Downloads
Published
Issue
Section
License
Copyright © 2026 Щерзод Менглиев, Хихматулло Насуллаев, Шухрат Гуломов, Руслан Хабипов, Мунаввар Аметова, Муниса Меркулова
This work is licensed under a Creative Commons Attribution 4.0 International License.
This work is licensed under a Creative Commons Attribution 4.0 International License.
How to Cite
