Limited ion-ion selectivity of salt-rejecting membranes due to enthalpy-entropy compensation was written by Shefer, Idit;Peer-Haim, Ophir;Epsztein, Razi. And the article was included in Desalination in 2022.Electric Literature of ClLi The following contents are mentioned in the article:
Water and ion transport in salt-rejecting membranes, such as nanofiltration (NF) and reverse osmosis (RO), are exposed to different hindrance effects that result in selectivity between species. In this study, we explored systematically the hindrance effects that govern water-salt and ion-ion selectivity in NF and RO membranes. More specifically, we measured the permeability of different species at varying temperatures and applied an Eyring-type equation to quantify the enthalpic and entropic barriers for their transport in three types of salt-rejecting membranes. We found that water-salt selectivity is entropically driven, where water mols. gain entropy in the membrane, while the salt ions face a substantial entropic barrier due to their larger size that reduces their possible configurations in the membrane. As the enthalpic barriers of the water and salt did not show a prominent difference (with minor effect on the water-salt selectivity), most ion-ion separations were restricted by an enthalpy-entropy compensation (EEC) effect; i.e., an ion with a higher entropic barrier experienced a lower enthalpic barrier compared to the competing ion, resulting in minor variations in the free-energy barriers between ions that limit the ion-ion selectivity. We conclude by proposing possible mechanisms that promote EEC during ion transport in salt-rejecting membranes. This study involved multiple reactions and reactants, such as Lithium chloride (cas: 7447-41-8Electric Literature of ClLi).
Lithium chloride (cas: 7447-41-8) belongs to organic chlorides. An organic chloride is an organic compound containing at least one covalently bonded atom of chlorine. Their wide structural variety and divergent chemical properties lead to a broad range of names and applications. Organochlorine compounds are lipophylic, meaning they are more soluble in fat than in water. This gives them a high tenancy to accumulate in the food chain (biomagnification).Electric Literature of ClLi
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics