Abstract |
Fe(III) can be easily extracted from weak acidic solutions by organophosphorus extractants, but stripping a large amount of Fe(III) from the loaded extractants is very difficult. The extraction and stripping of Fe(III) from 2 pH chloride and sulfate solutions was performed with ionic liquids(ILs) and organophosphorus acidic extractants, and the behaviors compared. As ionic liquids, two succinimides ([N88SA][C4min] and ([N88SA][C4Py]) were used, and bi-functional ionic liquids (Bif-ILs) synthesized from Aliquat336 and the organophosphorus acids Cyanex272, D2EHPA, and PC88A were employed. The extraction of Fe(III) by the ILs and extractants employed in this work was in the following order: organophosphorus extractants > Bif-ILs > succinimide ILs. The extraction of Fe(III) by succinimide ILs and Bif-ILs was higher from the chloride solution than from the sulfate one, while the nature of the medium had little effect on the extraction of Fe(III) by the organophosphorus extractants. FT-IR spectra confirmed the ion exchange mechanism of Fe(III) by the succinimide ILs. There was little difference in the stripping of Fe(III) by H2SO4 from the loaded Bif-ILs and the organophosphorus acids. However, stripping of Fe(III) from the loaded Bif- ILs using HCl did not readily occur. Fe(III) was readily stripped from the loaded [N88SA][C4min] and [N88SA][C4Py], and the HCl solution was more effective for stripping than H2SO4. [N88SA][C4min] is considered a promising new extractant for the recovery of Fe(III) based on its Fe(III) extraction and stripping behavior from weak acidic solution.
(Received September 18, 2019; Accepted October 29, 2019) |
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Key Words |
ionic liquids, succinimide, extraction, stripping, iron(III) |
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