Conversion of glucose into furans in the presence of AlCl3 in an ethanol–water solvent system

2012 ◽  
Vol 116 ◽  
pp. 190-194 ◽  
Author(s):  
Yu Yang ◽  
Changwei Hu ◽  
Mahdi M. Abu-Omar
Keyword(s):  
Solvent System ◽  
Water Solvent

Effect of Cellulose Coating on Properties of Cotton Fabric

2016 ◽  
Vol 860 ◽  
pp. 81-84
Author(s):  
Bandu Madhukar Kale ◽  
Jakub Wiener ◽  
Jiri Militky ◽  
Hafiz Shahzad Maqsood
Keyword(s):  
Tensile Strength ◽  
Cotton Fabric ◽  
Solvent System ◽  
Dissolving Pulp ◽  
Cotton Fibers ◽  
Cellulose Solution ◽  
Dyeing Properties ◽  
Sem Micrographs ◽  
Coated Substrate ◽  
Water Solvent

Cellulose solution was used for coating and it was prepared by dissolving pulp cellulose in Urea-Thiourea-NaOH-Water solvent system. Reactive Red 240 dye was used for dyeing the coated as well as control cotton fabric. The effect of cellulose coating on the dyeing properties of cotton fabric was studied by measuring K/S values of the coated substrate at various concentrations of cellulose and dye. K/S value decreased after coating cellulose on the surface of cotton fabric. The lightness of cotton fabric increased after cellulose coating. SEM micrographs revealed that coated cellulose was attached to cotton fibers. Tensile strength increased after cellulose coating.

scholarly journals Pyrolyzing Renewable Sugar and Taurine on the Surface of Multi-Walled Carbon Nanotubes as Heterogeneous Catalysts for Hydroxymethylfurfural Production

Catalysts ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 517 ◽  
Author(s):  
Huiping Ji ◽  
Jie Fu ◽  
Tianfu Wang
Keyword(s):  
Carbon Nanotubes ◽  
Heterogeneous Catalysts ◽  
Metal Salt ◽  
Textural Properties ◽  
Solvent System ◽  
Hydrothermal Stability ◽  
Transportation Fuels ◽  
Water Solvent ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Conversion of biorenewable feedstocks into transportation fuels or chemicals likely necessitates the development of novel heterogeneous catalysts with good hydrothermal stability, due to the nature of highly oxygenated biomass compounds and the prevalence of water as a processing solvent. The use of carbon-based materials, derived from sugars as catalyst precursors, can achieve hydrothermal stability while simultaneously realizing the goal of sustainability. In this work, the simultaneous pyrolysis of glucose and taurine in the presence of multi-walled carbon nanotubes (MWCNTs), to obtain versatile solid acids, has been demonstrated. Structural and textural properties of the catalysts have been characterized by TEM, TGA, and XPS. Additionally, solid state nuclear magnetic resonance (ssNMR) spectroscopy has been exploited to elucidate the chemical nature of carbon species deposited on the surface of MWCNTs. Al(OTf)3, a model Lewis acidic metal salt, has been successfully supported on sulfonic groups tethered to MWCNTs. This catalyst has been tested for C6 sugar dehydration for the production of HMF in a tetrahydrofuran (THF)/water solvent system with good recyclability.

scholarly journals Liquid-liquid equilibria of phenol-water-solvent system.

1988 ◽  
Vol 14 (4) ◽  
pp. 531-535 ◽  
Author(s):  
Syogo Takahashi ◽  
Kazutoshi Otake ◽  
Tolu Takahashi ◽  
Akihiro Iguchi
Keyword(s):  
Solvent System ◽  
Water Solvent ◽  
Phenol Water

Meisenheimer Complex Formation Between 1,3,5-Trinitrobenzene and Hydroxide Ion. Equilibrium Constants for the Dimethylformamide–Water Solvent System

1972 ◽  
Vol 50 (11) ◽  
pp. 1729-1733 ◽  
Author(s):  
E. A. Symons ◽  
E. Buncel
Keyword(s):  
Complex Formation ◽  
Aqueous Medium ◽  
Equilibrium Constant ◽  
Equilibrium Constants ◽  
Solvent System ◽  
Medium Composition ◽  
Hydroxide Ion ◽  
Spectrophotometric Methods ◽  
Water Solvent ◽  
Sigma Complex

Sigma-complex formation between 1,3,5-trinitrobenzene (TNB) and hydroxide ion has been studied quantitatively as a function of medium composition for part of the dimethylformamide (DMF)–water solvent system by spectrophotometric methods. Only a 1:1 complex is detected under the conditions of measurement, with [TNB] ≥ [OH−]. The equilibrium constant (Keq) for complex formation in 22 mol % DMF has the value 3 × 10−3 l mol−1, compared with 3 l mol−1 in purely aqueous medium. Further increases in Kcq occur as the DMF content of the medium is raised; in 50 mol % DMF Keq ≈ 105, but reliable Keq values could not be obtained in this region of medium composition. The increase in Keq with increasing DMF content is interpreted largely on the basis of hydroxide ion desolvation.

Isomerization of Retinyl Palmitate Using Conventional Lipid Extraction Solvents

1983 ◽  
Vol 66 (3) ◽  
pp. 746-750
Author(s):  
Mary C Mulry ◽  
Ronald H Schmidt ◽  
James R Kirk
Keyword(s):  
High Performance ◽  
Methylene Chloride ◽  
Lipid Extraction ◽  
Chlorinated Solvents ◽  
Solvent System ◽  
Retinyl Palmitate ◽  
Fluorometric Detection ◽  
Butyl Ether ◽  
Water Solvent ◽  
Extraction Solvents

Abstract The use or a chlorotorm-ethanol-water solvent system for the direct extraction of retinyl palmitate isomers from fortified food products was previously shown to be unsuitable because significant isomerization of all-trans-retinyl palmitate occurred during the extraction. This study investigated the extent of isomerization of retinyl palmitate in various extraction solvents when subjected to gold fluorescent laboratory light. Purified solutions of all-trans-retinyl palmitate in hexane were diluted with methyl t-butyl ether, hexane, methylene chloride, and stabilized chloroform and subjected to gold fluorescent laboratory light for 2, 4, and 6.5 h. Similar solutions were subjected to light or kept in the dark for 3.5 h. All-trans-, 9-cis-, and 13-cis-retinyl palmitate esters in the solutions were determined by using normal phase high performance liquid chromatography with fluorometric detection. Results demonstrated a noticeable increase in the 9-cis-retinyl palmitate concentration and a corresponding decrease in all-trans-retinyl palmitate concentration with time, in chloroform and methylene chloride compared with hexane. Chlorinated solvents in the absence of light did not promote isomerization of retinyl palmitate. Use of chlorinated solvents for the extraction of vitamin A esters should be avoided because they promote isomerization of retinyl palmitate when subjected to light, including gold fluorescent laboratory light.

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