Abstract
The efficiency of certain additives like tryptophan (TRP), adenosine monophosphate (AMP) and phenethylamine (PEA) on polyamide membrane (PA) surface for better salt rejection is studied through density functional theory. The interaction energies of monovalent (Na+, K+) and divalent (Ca2+, Mg2+) cations with pure PA and modified PA surfaces are calculated and a stronger binding of divalent cations over monovalent cations is noticed. The increasing order of binding of PA surfaces with metal-ions is PA_PEA<PA<PA_AMP<PA_TRP. The two major factors influencing the binding of metal ions to the surfaces are cation–π interactions between the metal ion and the π-cloud of the additive and the nucleophilic character of the membrane surface. The increasing order of metal ion binding to any of the PA surface is K+<Na+<Ca2+<Mg2+. Both gas phase and solvent phase interaction energies follow the same trend of metal ion binding to the PA surface. The findings from the interaction studies are supported by conceptual density functional descriptors. TRP and AMP bound PA surfaces with polar functional groups are relatively presented as an effectual membrane surface for salt rejection than the pure polyamide surface.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
