Chloride-containing ionic liquids

D.1.1. Chloride-Containing Ionic Liquids. The melting points of some typical [AMIMJCl compounds are shown in Table I. Except for dimethylimidazolium chloride, which has a melting point above 120°C, the higher-alkyl [AMIM]C1 ionic liquids melt at temperatures below 100°C. 

The ionic liquids made of ferric chloride and tin chloride displayed good properties as alternative catalysts in the acylation reactions (127). For the acylation of mesitylene with acetylchloride and for the acylation of anisole with acetylanhydride, the best results were obtained with a ferric chloride-containing ionic liquid. The conversions were much higher, and the selectivity obtained was in the same range relative to those observed with the Al- and Sn-chloride-containing ionic liquids. 

In-situ IR-spectroscopic characterization of the Friedel-Crafts acylation of benzene in ionic liquids derived from AICI3 and FeCl3 showed that the mechanism of the reaction in ionic liquids was the same as that in 1,2-dichloroethane (128). The immobilization of ferric chloride-containing ionic liquid onto solid supports (e.g., silica and carbon) however failed to catalyze the acylation reaction, because leaching was a serious problem. When the reaction was carried out with gas-phase reactants, catalyst deactivation was observed. 

For the ir-eleccron dispersion forces the choice of the anion also plays a significant role, y " for toluene is lowest for the [BTA]-anion, followed by [OAc] , [CH3S04] and [BFJ, which feature similar values. The highest y" of toluene, and hence the lowest degree of interaction, is found for the chloride-containing ionic liquid. 

In contrast, in the presence of MBT, a clear plateau is observed in tlry and chloride-free BMIBF4 (Fig. 7, but not in wet and chloride-containing ionic liquid) at potentials about 100 mV above the corrosion potential indicating a layer of corrosion products, which substantially depress the corrosion rate. 

The results of gravimetric study are summarized in Table 1. Surprisingly the increase of temperature from 50 to 200 °C does not substantially accelerate the mass loss. Addition of MBT depressed the mass loss of all 3 metals irrespective of the temperature. It should be emphasized that the ionic liquids underwent a partial thermal decomposition at 200 °C, but this process was rather slow except for chloride-containing ionic liquid in contact with Cu, in which the thermal decomposition was faster than in other studied systems. 

Wet and chloride-containing ionic liquid leads to higher concentration of B and F in the corrosion products. The presence of MBT induces a substantial decrease in the concentration of the products of decomposition of ionic liquid in the corrosion products in spite of relatively low concentration of MBT (cf. the concentration of S reported in Table 2). This result proves a strong interaction between MBT and steel and suggests that MBT adsorption occurs directly on the surface. 

The solubility parameters (total as well as the van der Waals and electrostatic components) for the family of ionic liquids studied are summarized in Table 5.4 (chloride-containing ionic liquids were omitted due to reasons explained above). 

A limitation of aluminum-containing ionic liquids arises from their moisture sensitivity. Moreover, most transition metal complexes and organic reactants are not unreactive in the presence of the chloroaluminate compounds. These ionic liquids react with water in a highly exothermic manner, with the formation of hydrogen chloride and a white precipitate. 

D.1.2. N-alkylpyridinium-Containing Ionic Liquids. The melting point of N-alkylpyridinium chloride increases from 70 to 80°C when the alkyl chain is lengthened from Ci2 to Cig. The melting point of iV-alkylpyridinium [NiCl4]J changes only from 80 to 86°C as the substituent changes from C12 to Cig 62). 

CdTe, a II—VI compound semiconductor with a direct band gap of 1.44 eV at room temperature, is, from its physical properties, a promising photovoltaic material. The electrodeposition of CdTe in ionic liquid was published recently by Sun et al. [38]. They were able to show that the semiconductor can be electrodeposited at elevated temperature (above 120 °C) in the Lewis basic l-ethyl-3-methylimidazolium chloride/tetrafluoroborate ionic liquid containing CdCh and TeCU. CdTe films were obtained by the underpotential deposition (UPD) of Cd on the deposited Te. The deposit composition was independent of the deposition potential within the Cd UPD regime. The crystallinity of the deposits is improved by increasing the deposition temperature, which again demonstrates the high potential of the wide thermal windows of ionic liquids for compound electrodeposition. 

Maminska et al. [71] worked on all-solid-state micro-reference electrodes dedicated to the flow-through analysis. A flat Ag AgCl microelectrode was covered by a membrane made from poly(vinyl chloride) which contained ionic liquid 1-dodecylo-3-methyl-imidazol chloride. The presence of this ionic liquid kept the concentration of chloride ions constant which stabilized the potential. The potential of such electrodes was found to be independent of the concentration of such anions as CP, Br, and NO3. ... 

More detailed investigations pjerformed by our group dealing both with the synthesis and characterization of the formed nickel salts (chloride and for the first time sulphate) containing ionic liquids and the electrochemical Ni deposition onto various metallic substrates to get more consistent information on the technological parameters, will be presented in the next sections. 

Nickel electrodeposition from choline chloride based ionic liquids containing chlorides... 

The Ni electrodeposition from choline chloride based ionic liquids containing the metallic cation as sulfate (see Table 3) was also investigated, onto the same previously mentioned metallic substrates, respectively Cu, A1 and Mg ones. The electrolysis was performed using a Ni anode for coating durations between 30-60 minutes. 

Nitrogen Compounds Contained in Straight-Run Diesel Feed Using Chloride Based Ionic Liquid. Ind. Eng. Chem. Res., 47,8801-8807, ISSN 0888-5885. 

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