Mercury capture on a supported chlorocuprate(ii) ionic liquid adsorbent studied using operando synchrotron X-ray absorption spectroscopy

Abstract

Hardacre, C., ... Swadzba-Kwasny, M. (2016). Mercury capture on a supported chlorocuprate(II) ionic liquid adsorbent studied using operando synchrotron Xray absorption spectroscopy.

Lewis Acidic Ionic Liquids

“…Raman, ab initio [47] Zn(II) Crystal structure [50], 199 Hg NMR, Raman [51], EXAFS [52] Al(III) 27 Al NMR [20] 71 Ga NMR, EXAFS [53][54][55] In(III)…”

Tackling elemental mercury removal from the wet-gas phase by enhancing the performance of redox-active copper-based adsorbents utilising an operando pre-heating system

“…the d-d ligand field transition, suggested a different Cu(II) ion coordination in comparison to the CuCl 2 on silica. 41 For NaCl on silica, it was found to have an immediate breakthrough, and this is in line with the thermodynamics of chemical reactions, where the reactivity of NaCl and Hg(0) is thermodynamically infeasible via the Ellingham diagram plot. [51][52][53][54] Based on these results, selected samples on activated carbon and silica were chosen for testing under the wet-gas conditions, that are the preferred conditions for mercury removal in this work.…”

“…49 The enhancement of the mercury extraction performance was previously discussed to be possibly due to dispersion effects, supported by the scanning electron microscopy studies. 50 For bulk [C 4 mim]Cl-CuCl 2 (χ CuCl 2 = 0.5), it formed the chlorocuprate(II) ion, which is likely to be [Cu 2 Cl 6 ] 2-, 38,41 and this chlorocuprate(II) is expected to function differently than the CuCl 2 . The species of [C 4 mim]Cl-CuCl 2 (χ CuCl 2 = 0.5) on the silica support is unknown, but the electronic absorption spectra, i.e.…”

“…65 Further, the comproportionation reaction between Hg(II) in the complex with the incoming Hg(0), leading to the formation of stable compounds as calomel, is also feasible. 41…”

“…The applications of these solidsupported ionic liquid phase (SILP) materials have shown superior performance for mercury removal and have been successfully operating in our commercial gas plants since 2011. [38][39][40][41] We report herein a solution for Hg removal from the natural gas phase that contains moisture in the lower temperature regions of the plant (25-40°C) and more specifically, for application in wet-gas conditions, using CuCl 2 as the reactive chemical supported on selected solid supports. Wet-gas is defined as the gas that does not meet the pipeline quality for natural gas due to the presence of undesirable components such as free water, water vapour and/or higher hydrocarbons that might result in condensation under pipeline conditions.…”