Modelling and simulation of chemical reaction of porous MgCl2 pellets with NH3 by including impact of heat and mass transfer and structure change


Creative Commons License

Helvaci Z. K., KARAKAŞ G., ULUDAĞ Y.

Turkish Journal of Chemistry, vol.47, no.3, pp.572-582, 2023 (SCI-Expanded) identifier identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 47 Issue: 3
  • Publication Date: 2023
  • Doi Number: 10.55730/1300-0527.3561
  • Journal Name: Turkish Journal of Chemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.572-582
  • Keywords: ammonia, chemical heat pump, Magnesium chloride, modelling, reaction kinetics, transport phenomena
  • Middle East Technical University Affiliated: Yes

Abstract

The MgCl2–NH3 reactive system is investigated in terms of heat and mass transfer coupled with chemical reaction through numerical simulation. The reversible nature of the chemical reaction is captured by including adsorption and desorption terms in the rate expression simultaneously. The kinetic coefficients of the adsorption are directly adopted from the literature, while those for the desorption reaction are calculated based on the thermodynamic relations. The impact of changing pressure and pellet porosity are also investigated in the simulations. The initial temperature of the pellet is 300 K in all simulations. Temperature, NH3 pressure, and conversion distributions in the pellets, along with pellet swelling are obtained and presented as a function of time. The results indicated strong effects of heat transfer resistances in the pellets.