Removal of Rhodamine B from Water by Benzyl‐Functionalized Ionic Liquids

Abstract

The removal of rhodamine B by benzyl-functionalized ionic liquids (ILs) from water was carried out. Effects of aqueous pH value, concentration of rhodamine B, phase volume ratio, and the presence of salt on the extraction efficiency have been investigated. Experimental results showed that the extraction efficiency of rhodamine B decreased with the increase of pH value. Thermodynamic studies indicated that hydrophobic interaction is the main driving force, besides, p-p stacking, electrostatic interaction, and salting-out effect are also important for the extraction of rhodamine B. Notably, the quantitative extraction of rhodamine B into 1-butyl-3-benzylimidazolium bis(trifluoromethylsulfonyl)imide ([C 4 Bzim]NTf 2 ) was achieved even at the phase volume ratio V w /V IL ¼ 500:1. After extraction, [C 4 Bzim]NTf 2 , could be directly reused at least five times. These results suggest that the [C 4 Bzim]NTf 2 has potential application in the removal of rhodamine B from water.

Lab at home: 3D printed and low-cost experiments for thermal engineering and separation processes in COVID-19 time

“…The experimental values shown in this figure could be compared by the students with literature values obtained by other authors in the liquid-liquid extraction of rhodamine B, to determine the performance of limonene in this separation process. In the literature, students will find articles in which rhodamine B has been extracted from aqueous solutions using conventional organic solvents (toluene, benzene, xylene, or hexane) ( Elumalai and Muthuraman, 2013 ), ionic liquids ( Fan et al, 2016 ; Kumar et al, 2020 ), or soybean oil ( Jiao et al, 2016 ). The students will compare the results obtained using limonene and the other solvents used in literature, considering technical aspects (extraction yields, distribution ratios, selectivities, viscosities, and costs) but also sustainability aspects, comparing the methods of obtaining and synthesizing the different solvents.…”

Tunable aryl alkyl pyrazolium tetrafluoroborate ionic liquids/salts: synthesis, characterization, and applications for removal of methyl orange from aqueous solution

“…The results mentioned above indicate that the removal efficiencies are higher than 99.0% in the range of pH 4–10. Therefore, separating MO from TAAILs by changing the pH values of solutions is difficult [ 43 ]. Hence, the synthesized TAAIL was used directly for the next cycle of extraction.…”

Response to Comment on “Sustainable Cotton Dyeing in Nonaqueous Medium Applying Protic Ionic Liquids”

“…In recent years, in view of the urgent need to modernize the textile industry, mainly due to the reduction of production costs and growing international trade concurrency, a large number of studies have been carried out aiming at the applications of ILs into different stages of textile processing (textile spinning, − textile preparation, − textile coloration, ,− textile finishing, − textile wastewater treatment, − and removal of textile dyes). − …”