Insight into the role of ion-pairing in the adsorption of imidazolium derivative-based ionic liquids by activated carbon was written by Liu, Mengping;Zhu, Ling;Zhang, Xiaoxian;Han, Wenhui;Qiu, Yuping. And the article was included in Science of the Total Environment in 2020.Product Details of 79917-89-8 This article mentions the following:
The association of the cation and anion of ionic liquids (ILs) dominates the absorbability of ILs by activated carbon (AC). Nevertheless, the mechanism behind the role of ion-pairs is largely unknown. In this study, the adsorption of a series of imidazolium derivative-based ILs by AC was involved in response to the octanol-water partition coefficient (KOW), hydrogen bonding acidity (伪), ion-pair binding constants (KIP), binding energy of ion-pairs (Ebinding) and d. functional theory (DFT) calculation of ILs. A significant pos. correlation between lg KOW and Kd and between KIP and lg KOW was observed (p < 0.05). However, both Ebinding and 伪 was inversely proportional to KIP. Hence, the substitution of oxygen-containing functional groups, such as carboxyethyl, 1-methoxyethyl, and 1-(ethoxycarbonyl)methyl, on imidazolium ring enhanced the hydrogen bond interaction with water mols. and then weakened the binding of imidazolium cation and [NTf2]–, thereby reducing the adsorption of ILs to AC. DFT calculation further revealed that the polar substitution improved the electron d. and electronegativity of imidazolium skeleton. By contrast, the ILs functionalized with non-polar groups (e.g., Bu, allyl, and benzyl) generally displayed high KIP values and low 伪 values. Consequently, the formation of hydrogen bond between the oxygen-containing functional groups of IL cation and water would facilitate the dissociation of IL ion-pairs and then decrease the adsorption of ILs on AC. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-propylimidazolium Chloride (cas: 79917-89-8Product Details of 79917-89-8).
1-Methyl-3-propylimidazolium Chloride (cas: 79917-89-8) belongs to imidazole derivatives. The solubility of imidazoles in ethers is lower than that in alcohols and decreases with increasing chain length of the ethers . In contrast, the solubility of benzimidazoles in alcohols (C3鈥揅6) is higher than in water and generally decreases with a Imidazole is incorporated into many important biological compounds. The most pervasive is the amino acid histidine, which has an imidazole side-chain. Histidine is present in many proteins and enzymes, e.g. by binding metal cofactors, as seen in hemoglobin.Product Details of 79917-89-8
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem