Aluminum-27 and carbon-13 NMR studies of aluminum chloride-dialkylimidazolium chloride molten salts

Abstract

Mixtures of 1 -methyl-3-ethylimidazolium chloride and aluminum chloride form salts that are liquid at room temperature. As the proportions of organic chloride and aluminum chloride are varied, the 13C NMR chemical shifts of the cation carbons change and the 27A1 line widths of the chloroaluminate anions change. The 13C shifts may be explained by anion-cation interactions and the27A1 line widths by the presence of more than one type of chloroaluminate anion. Temperature-dependent 27A1 NMR results show chemical exchange between chloroaluminate anions in the aluminum chloride rich molten salts.

Conductivities of Room Temperature Molten Salts Containing AlCl3, Measured by a Computerized Direct Current Method

“…Figure 8 shows that the conductivity is m axim um at 50 mol% AICI3 and 30 to 80 °C. In the A1C13-EM IC m elt system, the acid-base equilibria of ionic reactions may be sim ilar to those in the A1C13-BPC m elt [22,23]. Figure 9 shows that there is an irregular change at 4 0 -7 0 mol% AICI3 and 5 0 -8 0°C.…”

Polymorphous crystals from chlorozincate-choline chloride ionic liquids in different molar ratios

“…The composition effect on the anion size and distribution may be analogous to the chloroaluminate ILs, which were previously intensively investigated. For example, the Raman [19] and NMR [20,21] spectra of the AlCl 3 -1-(1-butyl)-pyridinium chlor- [18] proposed Eq. (1) for the ChCl-ZnCl 2 IL at X(ZnCl 2 ) ¼ 0.67 and equilibria (2) and (3) for the explanation of actual zinc anions present.…”

Some physicochemical characteristics of molten salts derived from trimethylsulfonium bromide

“…Some formation of Al,CI,{ may be important at high (>64 mol%) AICl, mole fractions (5,6). The anion-cation interactions that take place in ambient temperature melts have been studied by NMR spectroscopy (7)(8)(9). In basic melts the organic cations interact strongly with halide ions, apparently through hydrogen bond formation; in particular, all three Im+ ring protons interact (1G13) with C1-.…”

“…In basic melts the organic cations interact strongly with halide ions, apparently through hydrogen bond formation; in particular, all three Im+ ring protons interact (1G13) with C1-. In acidic melts (excess AlCl, over C1-) little interaction seems to occur (7)(8)(9). Both AlC1,:BPC and AlC1,:ImCl melts do provide wide acidity ranges and electrochemical windows bu; take considerable time and work to obtain pure.…”