Document Type : Research Paper

Author

Assistant Professor, Faculty of Chemical and Materials Engineering, Shahrood University of Technology, Shahrood, Iran.

Abstract

In current work, perturbed chain-statistical associating fluid theory (PC-SAFT) equation of state (EoS) together with the reaction equilibrium thermodynamic model (RETM) was employed to correlate H2S solubility in three carboxylate ionic liquids including [emim][Ace], [bmim][Ace], and [hmim][Ace]. The RETM proposes a chemical reaction approach between ionic liquid (IL) (B) and H2S (A) in the liquid phase. Moreover, PC-SAFT EoS contributes to VLE calculations. All the H2S and the investigated ILs, as self-associating components, are assumed to follow the 2B association scheme. Five adjustable variables of PC-SAFT EoS for pure components were calculated using experimental data of liquid density and vapor pressure. Afterward, the binary systems were investigated by applying RETM. Indeed, two nested loops calculate the liquid phase, total pressure, and vapor phase concentrations, respectively. For these systems, an AAD% of 2.29%, 3.09%, and 7.65% was obtained for H2S–[emim][Ace], H2S–[bmim][Ace], and H2S–[hmim][Ace] systems, respectively.

Highlights

  • Pure [emim][Ace], [bmim][Ace], and [hmim][Ace] were modeled;
  • H2S solubility in three carboxylates ionic liquids was correlated using PC-SAFT EoSs;
  • RETM was applied to calculate the liquid-phase concentrations;
  • RETM–PCSAFT presents AADs% equal to 2.29%, 3.09%, and 7.65% for H2S–[emim][Ace], H2S–[bmim][Ace], and H2S–[hmim][Ace] systems respectively;
  • The results of RETM–PCSAFT were compared with those of RETM–CPA.

Keywords

Main Subjects

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