abstract
Two tricyanomethanide-based ionic liquids (ILs), namely, 1-ethyl-3-methylimidazolium tricyanomethanide ([C(2)C(1)im] - [TCM] ) and 1-butyl-4-methylpyridinium tricyanomethanide ([4-C(4)C(1)py] [TCM]), have been recently reported as effective solvents for the benzene, toluene, and xylene (BTX) extractive distillation from pyrolysis gasoline. The vapor-liquid or vapor-liquid-liquid equilibria (VLE/VLLE) of several {aliphatic + aromatic + [TCM]-based ILs} ternary systems related to pyrolysis gasoline were extensively determined by headspace gas chromatography on a wide range of temperatures and solvent-to-feed ratios. The cubic plus association equation of state (CPA EoS) was used to predictively describe the experimental VLE/VLLE from binary interaction parameters regressed from {hydrocarbon + IL} binary systems. Here, the VLE/VLLE related to the separation of the pyrolysis gasoline key components (n-octane and benzene) and other aliphatic/ aromatic challenging mixtures in terms of aliphatic/aromatic relative volatility are reported. Specifically, the VLE/VLLE data for {n-octane + benzene + IL}, {n-heptane + benzene + IL}, and {n-octane + toluene + IL} ternary systems were determined. The CPA EoS accuracy, robustness, and transferability between different systems are verified, with the advantages and limitations shown in previous works. Overall, the results obtained in this work lay the foundation for the implementation of the CPA EoS parameterization in a commercial simulator to rigorously simulate the multicomponent BTX extractive distillation from pyrolysis gasoline with ILs.
keywords
EQUATION-OF-STATE; PLUS; DESIGN; RECOVERY; SOLVENT; AROMATICS; BENZENE; MIXTURE
subject category
Engineering
authors
Ayuso, M; Palma, AM; Larriba, M; Delgado-Mellado, N; Garcia, J; Rodriguez, F; Coutinho, JAP; Carvalho, PJ; Navarro, P
our authors
acknowledgements
This work was partly developed in the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. The authors are also grateful to Ministerio de Economia y Competitividad (MINECO) of Spain and Comunidad Autonoma de Madrid for the financial support of projects CTQ2017-85340-R and P2018/EMT-4348, respectively. P.N. and P.J.C. thank FCT for awarding their postdoctoral grant (SFRH/BPD/117084/2016) and contract under the Investigator FCT 2015 (IF/00758/2015), respectively. N.D.-M. and M.A. also thank MINECO for awarding them an FPI grant (BES-2015-072855 and PRE2018-083728, respectively). M.L. thanks Ministerio de Eduacion, Cultura y Deporte of Spain, for awarding him a Jose Castillejo postdoctoral mobility grant (CAS17/00018). All authors thank Infochem-KBC for the Multiflash program that was used for CPA EoS calculations.