- Synthesis and dissolving power of 1-Alkyl-3-methylpyridinium-based ionic liquids
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1-Alkyl-3-methylpyridinium-based ionic liquids with substituents from C2 to C10 and anions Cl- and Br- were synthesized, and their dissolving power toward the cellulose was investigated. The results of quantum-chemical calculations of molecules of ionic liquids are presented.
- Sashina,Kashirskii,Zaborski,Jankowski
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- Effect of molecular structure of cation and anions of ionic liquids and co-solvents on selectivity of 5-hydroxymethylfurfural from sugars, cellulose and real biomass
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The concept of biorefinery still requires advancements in process development for energy and materials. Ionic liquids have been successfully used for several biorefinery applications including high yield synthesis of biofuels and value added platform chemicals. Designing suitable ionic liquid that is efficient in terms of cost as well as product selectivity is still highly needed. This study is carried out to check the effect of different anions of Bronsted acidic ionic liquids (BAILs), Bronsted Lewis acidic ionic liquids (BLAILs), Lewis acidic ionic liquids (LAILs) as well as organic electrolyte solutions (OES) for 5-HMF selectivities from monosaccharides, polysaccharides as well as lignocellulosic composite. Different variables and parameters such as Lewis acidity of anions, alkyl side chain of ionic liquid, metal chloride type and loading, time, temperature, substrate loading, polar protic and aprotic solvents are thoroughly studied for process optimization. Polar protic solvents added in [C1C4SO3HPy] based ionic liquids with CH3COO? and Cl? anions yielded 94 and 80% 5-HMF from fructose and glucose respectively in the presence of AlCl3 as Lewis acid. C4SO3H side chain yielding high from fructose and glucose is inefficient for conversion of cellulose and lignocellulose. High product selectivity from these biopolymers is achieved using butyl side chain with 3-methylpyridinium cation and chlorochromate anion.
- Muhammad, Nawshad,Naz, Sadia,Uroos, Maliha
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- Ion pairing in 1-butyl-3-methylpyridinium halide ionic liquids studied using NMR and DFT calculations
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We present the 1H, 13C and 15N NMR chemical shifts of bulk ionic liquids based on 1-butyl-3-methylimidazolium (the cation also known as 1-butyl-3-picolinium) halides (Cl-, Br- and I-) and tribromide (Br3-) salts. A characterization in solution of the analogous ICl2- and I3- salts is also reported. A series of DFT calculations has been run to predict the features of the NMR spectra of the pure ILs based on a few selected supramolecular ionic aggregates. To test the effect of temperature, and vibrational and conformational motions, only for the chloride salt, we also run first-principles molecular dynamics simulations of the ion pair in the gas phase, using the ADMP scheme (Atom Centered Density Matrix Propagation molecular dynamics model). The aim of our investigation is to test whether a simple DFT based approach of ion-pairing in ionic liquids is capable of providing reliable results and under which conditions the protocol is robust. We obtained a very good agreement between the calculated and experimental spectra for the three halides, where the bulk structure of the ILs is dominated by H-bond interactions between the X- anion (X = Cl, Br and I) and the ortho protons of the pyridinium ring (a structural arrangement not too different from the solid-state structure of pyridinium halides). In contrast, when the H-bond is weak, as in the Br3- case, a number of supramolecular arrangements exist in solution and the simple DFT calculations of a few selected cases cannot exhaustively explore the complete energy landscape. Moreover, the dynamic effects due to thermal motion, evaluated by ADMP MD simulations of the chloride salt, appear to be not very significant.
- Swamy, Vincent P.,Thulasiram, Hirekodathakallu V.,Rastrelli, Federico,Saielli, Giacomo
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- Thermal properties of 1-alkyl-3-methylpyridinium halide-based ionic liquids
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This study was carried out for the comparison of thermal properties that determine various conditions and methods, including the differential scanning calorimetry (DSC), thermogravimetry (DTG) and the Bo?tius heated stage. Series of 1-alkyl-3-methylpyridinium chloride- and bromide-based ionic liquids having alkylic chain lengths ranging from C2 to C10 were synthesized, and their thermal characteristics were defined: glass transitions, melting and decomposition. Detailed thermal properties of ionic liquids, obtained in this work, can be useful in a variety of chemical engineering processes that are related with their application.
- Sashina, Elena S.,Kashirskii, Dmitrii A.,Janowska, Grazyna,Zaborski, Marian
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- Alkylpyridiniumdicyanamides as polar solvents
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Alkylpyridinium cyanamide compounds (I) are new. Alkylpyridinium cyanamide compounds of formula (I) are new. R n 1>CN or 1-20C alkyl; R 2>1-20C alkyl; and n : 0-3. An independent claim is also included for the preparation of (I). [Image].
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Page/Page column 5
(2008/06/13)
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- Organic salt conditioner, organic salt-containing composition, and uses thereof
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The present invention relates to the use of, and a composition containing, at least one non-polymeric organic salt with a melting point of less than 60° C. These organic salts may be imidazolium, pyrazolium, pyridinium, pyrimidinium or tetraalkylphosphonium salts. The inventinon composition may be used for washing (cleaning) and/or conditioning keratin materials, and especially the hair.
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