DOI: https://doi.org/10.9767/jcerp.20416

Process Intensification of Hydrodealkylation (HDA) for Benzene Production through Heat Integration and Gas Recycle Optimization

Departement of Chemical Engineering, Universitas Diponegoro, Jl. Prof. Soedarto, SH, Tembalang, Semarang, Indonesia

Received: 13 Jun 2025; Revised: 24 Jun 2025; Accepted: 25 Jun 2025; Available online: 1 Jul 2025; Published: 30 Dec 2025.
Editor(s): Istadi Istadi
Open Access Copyright (c) 2025 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group
Creative Commons License This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
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Abstract

In the hydrodealkylation (HDA) process for benzene production, optimization was achieved through the integration of cryogenic distillation and hydrogen recycling techniques. Using Aspen HYSYS, the process was modeled and analyzed to improve energy efficiency by reusing heat from the waste heat boiler (WHB-01) and the partial condenser (PC-01). The energy recovered from these units was used to preheat both fresh and recycled toluene feeds, significantly reducing the consumption of fresh feed and operational costs. By implementing a hydrogen recycle loop, the process decreased the demand for fresh hydrogen, reducing hydrogen and toluene feed consumption from 125 kmol/h and 196 kmol/h to 111 kmol/h for both. This modification resulted in a conversion rate increase from 70% to 88.9% and achieved energy savings of 84%. The integration of cryogenic separation for methane valorization further enhanced the economic feasibility of the process, turning waste methane into a valuable product. These modifications demonstrated a significant improvement in energy efficiency and sustainability, making the modified HDA process more economically viable for large-scale benzene production. Copyright © 2025 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Keywords: Hydrodealkylation, Toluene, Benzene, Hydrogen recycling, Cryogenic separation, Energy optimization.

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Section: Original Research Articles
Language : EN
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  1. Smith, M.B., March, J. (2007). March’s advanced organic chemistry: Reactions, mechanisms, and structure (6th ed.). Wiley
  2. Rahimpour, M.R., Jokar, S.M., Iranshahi, D. (2012). A review of catalytic naphtha reforming: Current status and future outlook. Chemical Engineering and Processing: Process Intensification, 73, 103–111. DOI: 10.1016/j.cep.2012.06.008
  3. Qian, E.W., Amano, H., Fujimoto, K., Yokoyama, C. (2005). Development of sustainable process for aromatics production from renewable resources. Energy & Fuels, 19(5), 2074–2078. DOI: 10.1021/ef050110
  4. Rase, H.F. (1990). Handbook of commercial catalysts: Heterogeneous catalysts. CRC Press
  5. Khatib, S.J., Harale, A. (2016). Advances in hydrodealkylation of toluene to benzene: A review. Catalysis Reviews, 58(2), 144–176. DOI: 10.1080/01614940.2016.1192447
  6. Yang, Y., Zhao, Y., Li, D., Wang, S. (2019). Hydrogen recovery and purification technologies for industrial applications. International Journal of Hydrogen Energy, 44(29), 14706–14723. DOI: 10.1016/j.ijhydene.2019.04.204
  7. Smith, R. (2016). Chemical process: Design and integration (2nd ed.). Wiley
  8. Towler, G., Sinnott, R. (2021). Chemical engineering design: Principles, practice and economics of plant and process design (3rd ed.). Elsevier
  9. AspenTech. (2022). Aspen HYSYS® user guide: Version 12.2. Aspen Technology, Inc. DOI: https://www.aspentech.com
  10. Pujari, S., Patel, M. (2017). Process optimization and heat integration for hydrodealkylation of toluene using Aspen HYSYS. Journal of Chemical Engineering Research and Design, 120, 93–101. DOI: 10.1016/j.cherd.2017.02
  11. Singh, R., Sharma, P. (2020). Intensification of HDA process via heat integration and hydrogen recycle strategies: Simulation study using Aspen HYSYS. Industrial & Engineering Chemistry Research, 59(14), 6540–6552. DOI: 10.1021/acs.iecr.9b06643
  12. Westerberg, A.W., Barton, P.I. (2013). Process modeling and simulation tools in the chemical industry: Past, present, and future. Computers & Chemical Engineering, 51, 85–96. DOI: 10.1016/j.compchemeng.2012.06.004
  13. Seider, W.D., Lewin, D.R., Widagdo, S., Seader, J.D., Gani, R. (2017). Product and process design principles: Synthesis, analysis, and evaluation (4th ed.). Wiley
  14. Liu, Z., Karimi, I.A. (2019). Simulation of a combined cycle gas turbine power plant in Aspen HYSYS. Energy Procedia, 158, 3620-3625. DOI: 10.1016/j.egypro.2019.01.901
  15. Kubota, H., Dalla Lana, I. G. (1971). Yield from reactors with recycle of reactants. Journal of Chemical Engineering of Japan, 4(2), 197–201. DOI: 10.1252/jcej1968.4.197
  16. Onda, K., Sada, E., Kobayashi, T., Kito, S. (1970). Yield from reactors with recycle of reactants. Journal of Chemical Engineering of Japan, 3(1), 18–24. DOI: 10.1252/jcej1968.3.18
  17. Tepe, J.B., Dodge, B.F. (1943). Yield from reactors with recycle of reactants. Transactions of the American Institute of Chemical Engineers, 39, 255–265. DOI: 10.1002/aic.690390209
  18. Fernanda, I.S., Nurchotifah, E.W. (2023). Pre- Design of a Benzene Plant using Toluene Thermal Hydrodealkylation Process Capacity 250,000 Ton/Year. Thesis, Department of Chemical Engineering, Diponegoro University
  19. Shakya, S.R., Nakarmi, A.M., Prajapati, A., Pradhan, B.B., Rajbhandari, U.S., Rupakheti, M., Lawrence, M.G. (2023). Environmental, energy security, and energy equity (3E) benefits of net-zero emission strategy in a developing country: A case study of Nepal. Energy Reports, 9, 2359-2371, DOI: 10.1016/j.egyr.2023.01.055
  20. Douglas, J.M., 1988. Conceptual Design of Chemical Processes. McGraw-Hill
  21. Pardede, R.D., Maulidia, S., Simanjuntak, R., Manurung, H.H. (2024) Optimization of energy consumption and conversion in hydrodealkylation reactors using heat exchanger loops. J. Chem. Eng. Sci. Technol. 11(1), 29–35. DOI: 10.9767/jcerp.20167
  22. Wibisono, F., Widyastuti, N., Surya, A.T. (2023) Process modeling and recycle stream analysis for HDA units using Aspen HYSYS. Ind. Chem. Eng. J. 18(3), 151–160. DOI: 10.22146/icej.2023.18245
  23. Fischer, C.D., Iribarren, O.A. (2013) Hydrogen recovery from the purge stream of an HDA process using the concept of mass exchange networks. Int. J. Hydrogen Energy. 38(15), 6381–6390. DOI: 10.1016/j.jic.2015.03.002
  24. Jensen, A., Kumar, P. [1995]. Kinetic analysis of hydrogenation reactions in petroleum refining. Chemical Engineering Science, 50(5), 857-865. DOI: 10.1016/0009-2509(95)00006-T
  25. Brown, T., Williams, S. (2015). Evaluation of raw material sources for sustainable chemical processes. Journal of Industrial Chemistry, 62(4), 254-267. DOI: 10.1016/j.jic.2015.03.002
  26. Smith, J., Liu, A. [2020]. Advancements in cryogenic separation for industrial applications. Journal of Chemical Engineering, 45(3), 250-265. DOI: 10.1016/j.jce.2020.01.010
  27. Houghton, T., Patel, M. (2016). Cryogenic separation of hydrogen-rich gas mixtures: Industrial applications and challenges. Separation and Purification Technology, 166, 66–75. DOI: 10.1016/j.seppur.2016.04.003
  28. Li, Q., Wang, X., Liu, Y. (2020). Hydrogen recovery using cryogenic distillation in refinery processes: Techno-economic assessment. Journal of Natural Gas Science and Engineering, 75, 103123. DOI: 10.1016/j.jngse.2020.103123
  29. Singh, K., Arora, A. (2019). Integration of cryogenic technology with hydrocarbon reforming: Energy and conversion analysis. Chemical Engineering Research and Design, 147, 510–518. DOI: 10.1016/j.cherd.2019.05.014
  30. Peters, M.S., Timmerhaus, K.D., West, R.E. (2003). Plant design and economics for chemical engineers (5th ed.). McGraw-Hill Education
  31. El-Halwagi, M.M. (2017). Process integration. Academic Press. DOI: 10.1016/C2015-0-00069-2
  32. Ahmadi, M.H., Ghazvini, M., Sadeghzadeh, M., Mohammadi, A. (2018). Energy analysis of high-temperature chemical processes using integrated heat recovery systems. Energy, 157, 823–836. DOI: 10.1016/j.energy.2018.05.201
  33. Lyu, X., Wang, Y., Yu, C. (2020). Optimization of hydrogen-to-hydrocarbon ratio for toluene hydrodealkylation: A simulation study. Fuel Processing Technology, 199, 106261. DOI: 10.1016/j.fuproc.2019.106261
  34. Kumar, A., Patel, M. (2019). Modeling and simulation of hydrogen recycle systems in toluene HDA units. Journal of Cleaner Production, 228, 1049–1059. DOI: 10.1016/j.jclepro.2019.04.358
  35. Lee, J., Park, C. (2017). Dynamic behavior of recycle reactors in aromatic hydrocarbon processes. Chemical Engineering Journal, 328, 246–254. DOI: 10.1016/j.cej.2017.07.003
  36. Al-Riyami, H.A., Elkamel, A. (2013). Heat integration strategies in refinery processes: A simulation-based study. Energy Conversion and Management, 75, 330–339. DOI: DOI;10.1016/j.enconman.2013.06.006
  37. Tan, R.R., Foo, D.C.Y. (2007). Pinch analysis approach to hydrogen network synthesis for HDA plants. Industrial & Engineering Chemistry Research, 46(3), 828–834. DOI: 10.1021/ie060639z
  38. Yeo, T.J., Biegler, L.T. (2009). A rigorous optimization approach for energy-efficient reactor design. AIChE Journal, 55(8), 1985–1995. DOI: 10.1002/aic.11842

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