Zwitterionic Compounds Derived from Structural Motifs of Ionic Liquids: Computational Insights Into Green and Sustainable Processes

12/06/2024

In alignment with Green Chemistry principles, zwitterionic (ZW) compounds are explored as safer alternatives to ionic liquids (ILs) in applications where lower toxicity is beneficial. This work investigates the structural similarity between ZWs and ILs using molecular dynamics simulations, focusing on neat systems of imidazolium-sulphonate (aromatic) and quaternary ammonium-sulphonate (non-aromatic) ILs and their analogous ZWs, as well as aqueous systems of imidazolium-sulphonate ILs/ZWs. The findings reveal that ZWs exhibit stable polar and nonpolar networks closely resembling those of ILs. Non-aromatic systems showed structural consistency across analogous IL/ZW pairs. In aromatic systems, variations in imidazolium ring substituent chain lengths did not disrupt polar network integrity. However, introducing polar oxyethylene groups into the alkyl chains disrupted nonpolar domain formation. In aqueous systems, ZWs demonstrated structural identity with their IL counterparts while exhibiting notable water solubility. Interactions between the sulphonate group and water were stronger than those between imidazolium and water. As dilution increased, ion-water interactions became more pronounced, while ion-ion interactions weakened, disrupting the polar network and leading to smaller ZW aggregates. At higher dilutions, oxyethylene substituent ZWs preferred smaller aggregates compared to alkyl counterparts. These findings enhance the understanding of zwitterionic compounds, supporting their potential as safer alternatives to ILs. By elucidating the similarities between the structural behaviours of ZWs with their analogous ILs, this work paves the way for the rational design of zwitterionic formulations for enhanced functionalities in energy storage and life sciences, while minimising toxicity.

Authors in the community:

• 

  T

  Tomás Teodoro de Carvalho

  ist196640

Supervisors of this institution:

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  K

  Karina Shimizu

  ist32907

• 

  A

  Adilson Alves de Freitas

  ist90208

chemical-engineering - Chemical engineering

por - Portuguese

Instituto Superior Técnico