Use of ionic liquids as ‘green’ solvents for extractions

Abstract

This review summarizes recent applications of ionic liquids (ILs) as ‘green’ solvents in extractions of a variety of substances, including metal ions, organic and bio‐molecules, organosulfur from fuels, and gases. ILs could also be used along with another ‘green’ technology, supercritical fluid extraction (SFE), for a more effective separation of products from ILs. In addition to their environmentally‐benign feature, ILs have other favorable properties over organic solvents used for extraction, such as adjustable hydrophobicity, polarity and selectivity. Copyright © 2005 Society of Chemical Industry

Separation of Organic Nitrogen Compounds by Supported Liquid Membranes Based on Ionic Liquids

“…Generally, hydrodenitrogenation is the most diffi cult hydrogenation reaction because such deep hydrogenation processes have high energy and hydrogen consumption, so other processes are needed. Methods based on solvent extraction method have been proposed 4), 5) with the advantages of low energy cost, elimination of hydrogen usage, retention of the chemical structures of the fuels, and no special equipment requirements 6) . Novel desulfurization processes have been suggested for fuel oils based on photochemical reactions and solvent extraction 7) .…”

“…The suitability of ionic liquids as green solvents for chemical processes has been frequently recognized because of the negligible vapor pressure, as replacements for volatile, conventional organic solvents 8), 9) . Ionic liquids have been used to replace organic solvents in the fi eld of separation processes 6) . Desulfurization and denitrogenation have been investigated with solvent extraction using ionic liquids 10) 13) .…”

Studies Regarding the Influence of the Ultrasonication Conditions on the Adsorption Performance of Obtained Ionic Liquid Impregnated Materials

“…Therefore in the present paper was study the influence of the work condition of ultrasionication method upon the adsorption performance of the Florisil impregnated with 1-Butyl-3-methylimidazolium hexafluorophosphate- [BmimPF 6 ]. This ionic liquid was chosen because the imidazolium based ionic liquids were intensive investigated in literature and showed higher stability [25]- [27]. An inorganic solid support was used due to highly porous texture and large specific surface area.…”

Effects of Ionic Liquids and Supports on the Permeation of Organic Nitrogen Compounds through Supported Ionic Liquid Membranes

“…Generally, hydrodenitrogenation is the most difficult hydrogenation reaction because such deep hydrogenation processes have high energy and hydrogen consumption, so other processes are needed. Methods based on solvent extraction have been proposed [4,5] with the advantages of low energy cost, elimination of hydrogen usage, retention of the chemical structures of the fuels, and no special equipment requirements [5]. Recently, desulfurization and denitrogenation have been investigated with solvent extraction [6][7][8] and supported liquid membranes (SLM) [9,10] using ionic liquids.…”