- Effect of cation structure on the oxygen solubility and diffusivity in a range of bis{(trifluoromethyl)sulfonyl}imide anion based ionic liquids for lithium-air battery electrolytes
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This paper reports on the solubility and diffusivity of dissolved oxygen in a series of ionic liquids (ILs) based on the bis{(trifluoromethyl)sulfonyl}imide anion with a range of related alkyl and ether functionalised cyclic alkylammonium cations. Cyclic voltammetry has been used to observe the reduction of oxygen in ILs at a microdisk electrode and chronoamperometric measurements have then been applied to simultaneously determine both the concentration and the diffusion coefficient of oxygen in different ILs. The viscosity of the ILs and the calculated molar volume and free volume are also reported. It is found that, within this class of ILs, the oxygen diffusivity generally increases with decreasing viscosity of the neat IL. An inverse relationship between oxygen solubility and IL free volume is reported for the two IL families implying that oxygen is not simply occupying the available empty space. In addition, it is reported that the introduction of an ether-group into the IL cation structure promotes the diffusivity of dissolved oxygen but reduces the solubility of the gas.
- Neale, Alex R.,Li, Peilin,Jacquemin, Johan,Goodrich, Peter,Ball, Sarah C.,Compton, Richard G.,Hardacre, Christopher
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- High-silica nanocrystalline Beta zeolites: Efficient synthesis and catalytic application
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An efficient synthesis methodology to obtain homogeneous nanosized high-silica Beta zeolites (~10-20 nm) with high solid yields (above 95%) using simple alkyl-substituted flexible dicationic OSDAs is described. These dicationic OSDAs allow the synthesis o
- Martínez-Franco, Raquel,Paris, Cecilia,Martínez-Armero, Marta E.,Martínez, Cristina,Moliner, Manuel,Corma, Avelino
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- Nanosized MCM-22 zeolite using simple non-surfactant organic growth modifiers: Synthesis and catalytic applications
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Non surfactant cyclic alkylammonium can selectively decrease the rate of crystal growth along the x-y crystal axes during the synthesis of MWW zeolite. This results in an ~60 nm nanocrystalline zeolite that shows remarkable catalytic properties for the production of cumene.
- Gallego, Eva M.,Paris, Cecilia,Martínez, Cristina,Moliner, Manuel,Corma, Avelino
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- Thermophysical and Electrochemical Properties of Ethereal Functionalised Cyclic Alkylammonium-based Ionic Liquids as Potential Electrolytes for Electrochemical Applications
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A series of hydrophobic room temperature ionic liquids (ILs) based on ethereal functionalised pyrrolidinium, piperidinium and azepanium cations bearing the bis[(trifluoromethyl)sulfonyl]imide, [TFSI]?, anion were synthesized and characterized. Their physicochemical properties such as density, viscosity and electrolytic conductivity, and thermal properties including phase transition behaviour and decomposition temperature have been measured. All of the ILs showed low melting point, low viscosity and good conductivity and the latter properties have been discussed in terms of the IL fragility, an important electrolyte feature of the transport properties of glass-forming ILs. Furthermore, the studied [TFSI]?-based ILs generally exhibit good electrochemical stabilities and, by coupling electrochemical experiments and DFT calculations, the effect of ether functionalisation at the IL cation on the electrochemical stability of the IL is discussed. Preliminary investigations into the Li-redox chemistry at a Cu working electrode are also reported as a function of ether-functionality within the pyrrolidinium-based IL family. Overall, the results show that these ionic liquids are suitable for electrochemical devices such as battery systems, fuel cells or supercapacitors.
- Neale, Alex R.,Murphy, Sinead,Goodrich, Peter,Hardacre, Christopher,Jacquemin, Johan
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- Colloidal and Nanosized Catalysts in Organic Synthesis: XXIII. Reductive Amination of Carbonyl Compounds Catalyzed by Nickel Nanoparticles in a Plug-Flow Reactor
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Reductive amination of aldehydes and ketones with primary and secondary amines under catalysis with nickel nanoparticles supported on zeolite X, MgO, or activated carbon in the gas phase or in the gas-liquid system in a plug-flow reactor proceeds at atmospheric pressure of hydrogen with the formation of secondary or tertiary amines in high yield.
- Mokhov, V. M.,Nebykov, D. N.,Paputina, A. N.,Popov, Yu. V.,Shishkin, E. V.
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p. 2333 - 2340
(2020/02/25)
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- Simple organic structure directing agents for synthesizing nanocrystalline zeolites
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The synthesis of the ZSM-5 and beta zeolites in their nanosized form has been achieved by using simple alkyl-substituted mono-cationic cyclic ammonium cations as OSDA molecules. The particular combination of a cyclic fragment and a short linear alkyl-chain group (preferentially C4) within the monocationic OSDA molecules allows directing the crystallization of nanosized zeolites with excellent solid yields (above 90%). Interestingly, the formation of the nanosized ZSM-5 and beta zeolites mostly depends on the size and nature of the cyclic fragment of the OSDA molecule, resulting in all cases in nanocrystalline solids with homogeneous distributions of particle sizes (~10-25 nm) and controlled Si/Al molar ratios (~15-30). The achieved nanosized ZSM-5 and beta zeolites have been extensively characterized by different techniques to study their physico-chemical properties, such as chemical composition, pore accessibility or Br?nsted acidity, among others. Moreover, the catalytic properties of the nanosized ZSM-5 and beta zeolites have been evaluated for different chemical reactions, including methanol-to-olefins (MTO) in the case of ZSM-5, and alkylation of benzene with propylene to obtain cumene and oligomerization of light olefins to liquid fuels in the case of beta, observing in all cases improved catalytic activity and product selectivity towards target products when compared to related catalysts.
- Gallego, Eva M.,Paris, Cecilia,Díaz-Rey, M. Rocío,Martínez-Armero, Marta E.,Martínez-Triguero, Joaquín,Martínez, Cristina,Moliner, Manuel,Corma, Avelino
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p. 8138 - 8149
(2017/11/27)
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- LOW VISCOSITY IONIC LIQUIDS
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Disclosed is an ionic liquid: wherein: n is 1 or 2; R1 is selected from H and (C1-C6)alkyl; R2 is selected from —(CH2)wO[(CH2)xO(CH2)y]m(CH2)zCH3 and wherein w is 1 to 6, x is 1 to 6, y is 0 to 6, z is 0 to 6, m is 0 to 3 and [w+m(x+y)+z] is less than or equal to 12; and R3 is selected from H and methyl, wherein if n is 1 then R3 is methyl, and if n is 2 then R3 is H. Also disclosed are electrochemical devices and devices employing such electrochemical devices as energy sources.
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Page/Page column
(2013/03/26)
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- LOW VISCOSITY IONIC LIQUIDS
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Disclosed is an ionic liquid formula (I): wherein: n is 1 or 2; R1 is selected from H and (C1-C6)alkyl; R2 is selected from -(CH2)wO[(CH2)xO(CH2)y]m(CH2)zCH3 and wherein w is 1 to 6, x is 1 to 6, y is 0 to 6, z is 0 to 6, m is 0 to 3 and [w+m(x+y)+z] is less than or equal to 12; and R3 is selected from H and methyl, wherein if n is 1 then R3 is methyl, and if n is 2 then R3 is H. Also disclosed are electrochemical devices and devices employing such electrochemical devices as energy sources.
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Page/Page column 18
(2011/09/15)
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- Azepanium ionic liquids
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The seven-member alicyclic secondary amine, azepane, has been used as starting material to synthesise a new family of room temperature ionic liquids. Such useful transformations of this coproduct of diamine production processes, generated in large amounts in the polyamide industry, would mitigate its disposal, which usually involves combustion. Reaction of azepane with 1-bromoalkanes or 1-bromoalkoxyalkanes produced the corresponding tertiary amines with good selectivity; further quaternisation reactions with the appropriate methylating agents yielded quaternary azepanium salts, [Rmazp]X (R = alkyl or alkoxyalkyl; X- = I-, [CF3CO 2]- or [OTf]-; Tf = (trifluoromethyl)sulfonyl). Analogous [NTf2]- salts have also been produced by metathetic reactions. Liquid temperature ranges are significantly affected by the nature of the anion and the substituents on the azepanium cation core; for example, [CF3CO2]- or [OTf]- salts based on cations with alkyl substitution are solids, whereas those with alkoxyalkyl substitution are liquids at ambient temperature. The crystal structures of [C4mazp][CF3CO2], [C 4mazp]I and [C6mazp][NTf2] (C4 = butyl, C6 = hexyl) are reported. The effects of the structural features of cations and anions on density, viscosity and conductivity data are discussed. The presence of ether linkages in the cationic side chains causes a marked decrease in viscosities and an increase in conductivities. Cyclic voltammetry showed that azepanium ionic liquids exhibit extremely wide electrochemical windows, thus becoming promising and safe alternatives to electrolytes based on volatile organic compounds. The Royal Society of Chemistry.
- Belhocine, Tayeb,Forsyth, Stewart A.,Gunaratne, H. Q. Nimal,Nieuwenhuyzen, Mark,Nockemann, Peter,Puga, Alberto V.,Seddon, Kenneth R.,Srinivasan, Geetha,Whiston, Keith
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experimental part
p. 3137 - 3155
(2011/12/04)
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- New ionic liquids from azepane and 3-methylpiperidine exhibiting wide electrochemical windows
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New ionic liquids based on azepanium and 3-methylpiperidinium cations have been synthesised; they exhibit moderate viscosities and remarkably wide electrochemical windows, thereby showing promise, inter alia, as electrolytes and battery materials, and as synthetic media.
- Belhocine, Tayeb,Forsyth, Stewart A.,Gunaratne, H. Q. Nimal,Nieuwenhuyzen, Mark,Puga, Alberto V.,Seddon, Kenneth R.,Srinivasan, Geetha,Whiston, Keith
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body text
p. 59 - 63
(2011/03/20)
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- IONIC LIQUIDS AS ELECTROLYTES
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The invention relates to an ionic liquid composition and a method for preparing the ionic liquid. The ionic liquid comprises a cation containing the FormulaI, disclosed, and wherein: n is 1 or 2, R1 is selected from the group consisting of: H, C1 - C12 alkyl, aryl or together with R2 may form a heterocyclic ring, and R2 is selected from the group consisting of: H, C1 - C12 alkyl, aryl or together with R1 may form a heterocyclic ring, and R3 is selected from the group consisting of hydrogen and C1-C12 alkyl, wherein if n is 1, then R3 is C1-C12 alkyl; and wherein R1 and R2 are not simultaneously selected from hydrogen. The method for the preparation of the ionic liquid composition provided herein starts with at least one N-substitution of the compound of Formula II, as herein disclosed, and wherein: n is 1 or 2, R3 is selected from the group consisting of hydrogen and C1-C12 alkyl, wherein if n is 1, then R3 is C1-C12alkyl. Further provided is a use of the ionic liquid in a chemical method including at least a method for electro-chemical oxidation.
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Page/Page column 14-15
(2009/01/24)
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- N-hydroxypyridine-2-thione carbamates. V. Syntheses of alkaloid skeletons by aminium cation radical cyclizations
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The title radical precursors (PTOC carbamates) were employed as sources of a variety of 5,6-unsaturated aminium cation radicals. 5-Exo radical cyclization followed by trapping by t-BuSH or the PTOC carbamate gave a variety of aklaloid skeletons, typically in good to excellent yields, including pyrrolidines, perhydroindoles, pyrrolizidines, tropanes, 9-azabicyclo[4.2.1]nonanes, 6-azabicyclo [3.2.1]octanes. 6-Exo and 7-endo cyclizations competed in a 6,7-unsaturated system.
- Newcomb, Martin,Marquardt, Donald J.,Deeb, Thomas M.
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p. 2329 - 2344
(2007/10/02)
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