Mixtures Of Aluminum Chloride Research Articles

Ternary Ionic Liquid Analogues as Electrolytes for Ambient and Low-Temperature Rechargeable Aluminum Batteries.

Rechargeable aluminum (Al) metal batteries are enticing for the coming generation of electrochemical energy storage systems due to the earth abundance, high energy density, inherent safety, and recyclability of Al metal. However, few electrolytes can reversibly electrodeposit Al metal, especially at low temperatures. In this study, Al electroplating and stripping were investigated from 25 °C to -40 °C in mixtures of aluminum chloride (AlCl3), 1-ethyl-3-methyl-imidazolium chloride ([EMIm]Cl), and urea. The ternary ionic liquid analogue (ILA) consisting of AlCl3-urea-[EMIm]Cl in a molar ratio of 1.3:0.25:0.75 enabled reversible Al electrodeposition at temperatures as low as -40 °C while exhibiting the highest current density and the lowest overpotential among all of the electrolyte mixtures at 25 °C, including the AlCl3-[EMIm]Cl binary mixture. The ILA electrolyte was further tested in a rechargeable Al-graphite battery system down to -40 °C. The addition of urea to AlCl3-[EMIm]Cl binary mixtures can improve the Al electrodeposition, extend the liquid temperature window, and reduce the cost.

Investigation of Conversion Positive Electrode Active Materials for the Aluminum Rechargeable Battery

Introduction As a post lithium ion battery, new rechargeable batteries with metal negative electrodes which form multivalent cations during discharging are actively being investigated because they are expected to have high specific power, high energy density and low cost. Mg is the most popular materials for the multivalent cation battery because it shows higher energy density (3837 mAh cm-3) than Li (2062 mAh cm-3). Al is two times as large in energy density (8043 mAh cm-3) as Mg. Thus Al rechargeable battery is a promising next generation power source. To construct the Al rechargeable battery, investigation of the positive electrode material is necessary. Preciously, we reported the Al rechargeable battery using V­­2O5 positive electrode and its specific capacity was about 200 mAh g-1, however this battery can only be charged/discharged with 1/10 ~ 1/40 C rate and it is too low charging/discharging rate for practical application.1) In this study, we have developed the Al rechargeable battery using CuF2 as the positive electrode to increase the high rate dischargeability. This battery can be operated with high charging/discharging rate, however, XRD data suggested that in the process of conversion reaction, CuCl and CuCl2 was produced by substitution of F- with Cl-supplied from the electrolyte. So, we also investigated transition chlorides (CuCl, CuCl2 CoCl2, FeCl2) as the conversion positive electrode active material for the Al rechargeable battery to increase specific power and energy density. Experimental All electrochemical measurements were performed with a glass cell. The electrolyte was a mixture of aluminum chloride, dipropylsulfone and toluene with the mole ratio of 1:10:5. An Al plate with diameter of 14 mm was used as counter and reference electrodes for all experiments. A glass fiber filter was used as separator. 44 mg of transition Chlorides and 5 mg of Ketjen black powders were mixed, and 1-Methyl-2-pyrrolidone and 4 mg of polyimide were added to the mixture to prepare a paste. The positive electrode was prepared by casting the paste onto a molybdenum current collector and drying at 230 °C. Results and discussions Figure 1 shows CVs of CuF2, CuCl and CuCl2 positive electrodes. Almost the same oxidation and reduction peaks were observed. This suggests that CuF2 was converted to CuCl or CuCl2 by substitution of F- with Cl-during charge-discharge reactions. An Al rechargeable battery using CuCl and CuCl2 as cathode material was fabricated and subjected to charge-discharge tests (Figure. 2). For the initial 15 cycles, discharge capacity was higher than 150 mAh g-1, suggesting CuCl and CuCl2 was a new positive electrode material for Al rechargeable battery. CoCl2 and FeCl2 positive electrodes showed oxidation and reduction peaks. However, their capacities were less than that of CuCl and CuCl2. Reference 1) M. Chiku et al. 224thECS Meeting # 521 Figure 1

The Effect of Chloride Ion in the Electrolyte of Al Rechargeable Battery

Introduction Mg metal is considered as a promising negative electrode material for the post Li-ion battery. However, we focused onto Al rechargeable battery because it shows highest energy density per volume (8043 mAh cm-3) and Al metal is abundant on the earth. Moreover, Al is stable in the atmosphere, therefore, Al rechargeable battery is essentially safe in the case of accidents. There are limited variety of materials as a candidate for the electrolyte of Al rechargeable battery because the number of the electrolyte which enable reversible electrochemical deposition and dissolution of Al metal is limited. Ionic liquid is one of the most popular electrolyte for Al deposition and it also used as the electrolyte for Al rechargeable battery. Jayaprakash et al. reported that they successfully constructed the rechargeable aluminum-ion battery using ionic liquid electrolyte, Al metal negative electrode and V2O5 positive electrode1). In contrast, Reed et al. suggested the V2O5 was not electrochemically active material and the iron and chromium in the stainless steel current collectors acted as positive electrode materials2). We used a mixture of aluminum chloride and dipropylsulfone (DPSO2) as electrolyte and constructed Al rechargeable battery using Al metal negative electrode and V2O5 positive electrode3). Our battery could be operated with the specific capacity about 150 mAh g-1 for 30 cycles. However, the electrochemical window of the electrolyte was limited by the oxidation of contained chloride ion and it constricted the cell voltage of Al rechargeable battery. In this study, we report the effect of chloride ion in the mixture of aluminum chloride and DPSO2 as the electrolyte for Al rechargeable battery. Experimental DPSO2/AlCl3 electrolytes were prepared by mixing DPSO2, AlCl3 and toluene with mole ratios of X:1:5 (0.5≦X≦10). All electrochemical measurements were examined with a two-electrode glass cell. A Mo plate was employed as the working electrode while an Al plate was employed as the counter and reference electrodes. The chloride ion free DPSO2/AlCl3 = 10 electrolyte was prepared using AgBF4. AgBF4 was added into the DPSO2/AlCl3 = 10 electrolyte and chloride ion was precipitated as AgCl. The supernatant liquid was used as chlorine free DPSO2/AlCl3 = 10 electrolyte. Results and discussions Figure 1a shows the CV of Mo electrode in the DPSO2 + AlCl3 + toluene solutions with different DPSO2/AlCl3 ratios. CV with the DPSO2/AlCl3 = 10 electrolyte showed reversible deposition and dissolution of Al metal. On the other hands, the DPSO2/AlCl3 = 1 electrolyte was electrochemically inactive. Figure 1b shows the NMR spectrum of these electrolytes. [Al(DPSO2)3]3+ was the main product in the DPSO2/AlCl3 = 10 electrolyte, whereas AlCl3-DPSO2 was the main product in the DPSO2/AlCl3 = 1 electrolyte. We suspected that almost all of chlorine was combined with Al ion in the DPSO2/AlCl3 = 1 electrolyte. To investigate the effect of chloride ion, we measured XPS of Al metal sheet following impregnation into these electrolytes. It clearly showed the chlorine content inside the Al oxides layer on the Al plate impregnated into the DPSO2/AlCl3 = 1 electrolyte was decreased. We also prepared the chloride ion free DPSO2/AlCl3 = 10 electrolyte. NMR and CV measurement results showed that almost all of Al was existed as [Al(DPSO2)3]3+ in the chloride ion free DPSO2/AlCl3 = 10 electrolyte and this electrolyte was electrochemically inactive. These features suggests the free chlorine content is essential for reversible Al deposition/dissolution reaction. Reference N. Jayaprakash, S. K. Das and L. A. Archer, Chem. Commun., 47, 12610 (2011)L. D. Reed and E. Menke, J. Electrochem. Soc., 160, A915 (2013)M. Chiku, H. Takeda, T. Kunisawa, E. Higuchi and H. Inoue, 224th ECS Meeting # 521

Properties of Heat Treatment Alkaline Pulping Black Liquor with Aluminum Chloride

The black liquor contains a large amount of suspended solids, organic pollutants and toxic substances, the black liquor discharged directly into water bodies will lead to serious pollution. So we regards the alkaline pulping black liquor as a research object, using autoclave to heat the mixture of aluminum chloride and soda black liquor lignin. By changing the heating temperature and the pH before the heat treatment, we analyze the lignin and carbohydrates in the cooking liquid to study cleavage situation and the corresponding structural changes. The results show that the lignin content accompanied the increase in temperature, organic matter content decreased and part of the decomposition of organic matter. Without adjusting pH, the lignin content is small and ash (inorganic) content is higher.

Orthoamide, LXIV [1]. Aromatenformylierungen mit Tris(dichlormethyl)amin und Oligoformylamin-Derivaten in Gegenwart von Supersäuren / Orthoamides, LXIV [1]. Formylation of Aromatic Compounds by Tris(dichloromethyl)amine and Oligoformylamine Derivatives in the Presence of Superacids

Tris(dichloromethyl)amine (4), triformamide (1) and tris(diformylamino)methane (“formylaalen”) (2) can be activated by addition of trifluoromethanesulfonic acid. The formylating systems thus formed transform activated aromatic compounds, such as toluene, anisole or 2,4- dimethoxybenzene to the corresponding aldehydes. The formylating ability of systems from 4 and superacids, such as FSO3H, FSO3H/SbF5, C4F9SO3H, and mixtures of aluminum chloride with C4F9SO3H and chlorosulfonic acid, respectively, is compared. In general, low reaction temperatures (−20 to −10 °C) are necessary to obtain aldehydes with acceptable to good yields. Remarkably, at higher temperatures (~ 100 °C) compound 4 can also act as a formylating agent in the presence of suitable zeolites, as e. g. zeolite HBEA. Reaction mechanisms of the new formylation reactions are proposed.

Determination of chloride ion diffusion coefficients for zinc dissolution in a low temperature molten salt

The transport properties and stoichiometry of the zinc dissolution process in mixtures of aluminum chloride and 1-methyl-3-ethylimidazolium chloride were studied. A new mass transfer correlation for rotating cylinder electrodes was found for these high Schmidt number electrolytes. Two limiting current regions were observed during the dissolution process which corresponded to a coordination number of four at low overpotentials and a coordination number of three at high overpotentials. The quantity Dμ/ T was calculated to be 3.5 × 10 −10, which corresponds to a chloride ion radius of 2.1 × 10 −8 cm.

Room Temperature Molten Salt Electrolytes for Photoelectrochemical Applications

Mixtures of aluminum chloride (AlCl3) with triethylammonium chloride (Et3NHCl), 1,6-ethyl lutidinium bromide (EtluBr), tert-butyl pyridinium bromide (BPBr), and dialkyl imidazolium chloride (R2ImCl), in certain molar ratios yielded ionic liquids at room temperature which were studied with respect to their applicability as electrolytes in photoelectrochemical (PEC) cells. Background voltammograms were obtained for these electrolytes on carbon and n-GaAs electrodes. The anodic stability limit was found to be enhanced on n-GaAs relative to carbon in all cases. The cathodic decomposition potential of the electrolyte showed a smaller positive shift on n-GaAs with the exception of the 3:1 AlCl3-BPBr electrolyte. The difference in electrolyte stability behavior on carbon and n-GaAs is interpreted in terms of carrier density effects. Cyclic voltammograms were compared on carbon in the various electrolytes for a model redox system comprising the ferrocene/ferricenium couple. The separation of the cathodic and anodic waves in all the cases was consistent with a quasi-reversible redox behavior—the most sluggish electron transfer being observed in the case of the 3:1 AlCl3-BpBr electrolyte. These results are compared with those obtained previously on the AlCl3-butyl pyridinium chloride (BPC) system. Capacitance-voltage measurements were made on n-GaAs electrodes in contact with the various electrolytes. Flatband-potentials (Vfb) were deduced from these data using Mott-Schottky plots. The relative positions of the n-GaAs band-edges and the redox levels were mapped on a common potential scale utilizing these data. The ferrocene/ferricenium redox level was placed negative of the conduction band-edge in n-GaAs in all the cases. The implications of this result for PEC applications and the role of specific ion adsorption of electrolyte species on the electrostatic aspects of the n-GaAs/molten salt electrolyte interface are discussed with the aid of energy band diagrams.

LOW TEMPERATURE CONVERSION OF PENTANE WITH ALUMINUM CHLORIDE–METAL SULFATE MIXTURES

Abstract The mixtures of aluminum chloride and metal sulfate are found to be effective catalysts for the conversion of pentane at low temperatures. For example, when 10 ml of pentane was shaked with the equimolar mixture of AlCl3 and Ti2(SO4)3 (7.5 mmol each) at 28 °C for 3 hr, the pentane conversion of 46 % was obtained with the selectivity to isopentane of 84 %. In the vapor phase conversion, however, the main product was found to be isobutane.

Recrystallization of aluminium in the molten mixture of aluminium chloride and sodium chloride

Recrystallization of aluminium in the molten mixture of aluminium chloride and sodium chloride

A STUDY OF SOME FACTORS INFLUENCING THE ACTIVITY OF ALUMINUM AND FERRIC CHLORIDES IN THE FRIEDEL AND CRAFTS REACTION

In the preparation of aluminum chloride by the action of hydrogen chloride on the metal, hydrogen chloride is adsorbed and can be recovered to the extent of about 9 cc. per gram. After sublimation in nitrogen and re-sublimation in hydrogen chloride, however, the amount of adsorption is smaller and irregular. The adsorbed gas is not removed by a stream of nitrogen at room temperature. The activities in the Friedel and Crafts reaction of various preparations of aluminum chloride and of ferric chloride and of mixtures of these were determined; the order of decreasing activity was found to be as follows: a mixture of aluminum chloride and ferric chloride, aluminum chloride made by the action of hydrogen chloride on aluminum, aluminum chloride made by the action of chlorine on aluminum, a mixture of aluminum chloride and partially reduced ferric chloride, ferric chloride, and partially reduced ferric chloride. The most striking result of the measurements is that although ferric chloride alone has an activity of only about one-third that of aluminum chloride, an approximately equimolecular mixture of the two has an activity somewhat greater than that of pure aluminum chloride.