Toluene methylation to para-xylene

Modeling of fixed packed bed reactor
  • Mahdi Abdi-khanghah
  • Abdullah A. A. A. Alrashed
  • Touba Hamoule
  • Reza Mosayebi Behbahani
  • Marjan Goodarzi


To investigate the effect of operational parameter and transport phenomena on para-xylene production from toluene methylation with methanol, a fixed bed tubular reactor packed with Al-HMS-5 mesoporous catalyst was numerically studied. A mechanistic Longmuir–Hinshelwood-type kinetic study has been implemented on a proposed reaction network based on former experimental observation and theoretical background. Kinetic parameters and activation energy related to proposed reaction network for toluene methylation were evaluated using nonlinear regression and Arrhenius plot, respectively. In addition, heat transfer, fluid flow, and chemical reaction equations consisting of toluene methylation and xylene isomerization were solved using finite element method. In order to optimize toluene methylation process, reaction temperature and residence time were investigated. The results showed that uniform distribution of temperature exists at the reactor. There is only deviation from uniform temperature at the reactor entrance, but in other places, the temperature distribution is uniform. As a result, fluid temperature quickly becomes the same as the wall temperature, making the toluene methylation reaction highly efficient. Finally, the residence time of 60 s and wall temperature of 425 K were recommended as optimum working values.


Para-xylene production Finite element method Al-HMS-5 catalyst Fixed bed reactor 


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  1. 1.Department of Gas EngineeringPetroleum University of TechnologyAhwazIran
  2. 2.Department of Automotive and Marine Engineering Technology, College of Technological StudiesThe Public Authority for Applied Education and TrainingAdailiyaKuwait
  3. 3.Department of Basic SciencePetroleum University of TechnologyAhwazIran
  4. 4.Sustainable Management of Natural Resources and Environment Research Group, Faculty of Environment and Labour SafetyTon Duc Thang UniversityHo Chi Minh CityVietnam

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