17 research outputs found
Resource Upgrading in Advanced Supercritical Fluid (Supercritical Fluid with Catalyst and Cosolvent): Liquid Fuels from Biomass in Sub and Supercritical Water and Carbohydrate Up-Conversion in Ionic Liquid and Supercritical Fluids Mixtures
Liquid fuels from biomass and up-conversion of biomass in advanced supercritical fluid are reviewed in this chapter. Lignin can be converted into heavy hydrocarbons in subcritical water extraction. Lipid, which is triglyceride, is catalytically converted into straight-chain hydrocarbons of free fatty acid (decarboxylation) formed by hydrolysis. Carbohydrate is also hydrothermally converted into furan ring compound and fatty acids. Protein is converted into amino acids in hydrothermal water and depolymerization of protein is favored with rapid heating and denaturation agency such as alkaline earth metals. Free amino acids are further decomposed into carboxylic acid through deamination and into amine through decarboxylation. To inhibit Maillard reactions, which result in polymerization, the deamination of amino acid at low temperature was favored and a solid catalyst was quite active for deamination of free amino acids at quite low temperature hydrothermal water. Cellulose was dissolved in some ionic liquids with high mass percentages (5–20 wt%) and converted into monomers and useful components such as furan ring compounds and supercritical fluid cosolvent such as hydrothermal water in ionic liquids supported improvement of reaction efficiency. For hydrogenation of biomass, it was confirmed that hydrogen solubility was enhanced with supercritical carbon dioxide and it must be helpful for hydrogen reaction with biomass molecule
Physical Properties and Models of Ionic Liquid-Supercritical CO2 Systems for Developing Biomass Reaction and Separation Processes
Densities at Pressures up to 200 MPa and Atmospheric Pressure Viscosities of Ionic Liquids 1‑Ethyl-3-methylimidazolium Methylphosphate, 1‑Ethyl-3-methylimidazolium Diethylphosphate, 1‑Butyl-3-methylimidazolium Acetate, and 1-Butyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide
High pressure densities at (10–200)
MPa over a range of
temperatures and atmospheric pressure viscosities at (293–373)
K for three ionic liquids (ILs) that are able to dissolve biomass,
1-ethyl-3-methylimidazolium methylphosphate ([emim][MP]), 1-ethyl-3-methylimidazolium
diethylphosphate ([emim][DEP]), and 1-butyl-3-methylimidazolium
acetate ([bmim][Ac]) are reported. Densities of the IL 1-butyl-3-methylimidazolium
bis(trifluoromethylsulfonyl)imide ([bmim][Tf<sub>2</sub>N])
were measured at the same conditions to verify the apparatus and to
extend the range of present data. The high pressure densities of [emim][MP]
and [emim][DEP] are newly measured in this work. Combined expanded
uncertainties of densities for [emim][MP], [emim][DEP], [bmim][Ac],
and [bmim][Tf<sub>2</sub>N] were estimated to be 1.5 kg·m<sup>–3</sup>, 1.4 kg·m<sup>–3</sup>, 1.4 kg·m<sup>–3</sup>, and 1.7 kg·m<sup>–3</sup>, respectively.
The Tait equation could correlate the experimental density data to
within 0.03 % of average relative deviation. The derivative properties,
isobaric expansivity, and isothermal compressibility were calculated
using the Tait equation and it was observed that the isobaric expansivity
decreased with increasing temperature. The trend of the isobaric expansivity
and isothermal compressibility with temperature were in accordance
with the theory of corresponding states using methanol for comparison
Measurement and Correlation of High-Pressure Densities and Atmospheric Viscosities of Ionic Liquids: 1‑Butyl-1-methylpyrrolidinium Bis(trifluoromethylsulfonyl)imide), 1‑Allyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide, 1‑Ethyl-3-methylimidazolium Tetracyanoborate, and 1-Hexyl-3-methylimidazolium Tetracyanoborate
Four ionic liquids,
[bmpyr][Tf<sub>2</sub>N] (1-butyl-1-methylpyrrolidinium
bis(trifluoromethylsulfonyl)imide), [amim][Tf<sub>2</sub>N] (1-allyl-3-methylimidazolium
bis(trifluoromethylsulfonyl)imide), [emim][TCB] (1-ethyl-3-methylimidazolium
tetracyanoborate), and [hmim][TCB] (1-hexyl-3-methylimidazolium tetracyanoborate),
were studied. High-pressure densities were measured at pressures up
to 200 MPa and at temperatures of 312−433 K. Densities and
viscosities at atmospheric pressure were measured over a temperature
range of 293 to 373 K, and average relative deviation (ARD) of correlation
with Vogel–Fulcher–Tammann equation for viscosity were
within 0.08%. Correlation of the density data with the Tait equation
could be obtained to within 0.02% ARD. Isobaric expansivities calculated
from the Tait equation were constant or decreased slightly with increasing
temperature in accordance with trends commonly reported for ionic
liquids. Parameters for the ε*-modified Sanchez–Lacombe
equation of state are tabulated that allow correlation of the ionic-liquid
high-pressure densities to within an ARD of less than 0.08%
Identification and expression analysis of a gene encoding a shikimate transporter of Corynebacterium glutamicum
Mechanism of Glucose Conversion into 5‑Ethoxymethylfurfural in Ethanol with Hydrogen Sulfate Ionic Liquid Additives and a Lewis Acid Catalyst
Hydrogen
sulfate ionic liquid additives with aluminum chloride
catalyst in ethanol were found to promote efficient (30 min) one-pot,
one-step transformation of glucose into 5-ethoxymethylfurfural (5-EMF)
in 37% yields. Spectroscopic measurements (FT-IR, <sup>1</sup>H NMR)
showed that ionic liquids form multiple hydrogen bonds with glucose
and promote its ring opening through ionic liquid–AlCl<sub>3</sub> complexes to enable formation of 5-EMF via 5-hydroxymethylfurfural
(5-HMF). Reactions performed in dimethyl sulfoxide using (protic,
aprotic) ionic liquid additives with and without AlCl<sub>3</sub> catalyst
showed that both the ionic liquid and AlCl<sub>3</sub> were required
for efficient transformation of glucose into 5-EMF. The proposed reaction
mechanism for 5-EMF synthesis in the ethanol–1-butyl-3-methylimidazolium
hydrogen sulfate–AlCl<sub>3</sub> reaction system consists
of ring opening of glucose to form the 1,2-enediol and dehydration
to form 5-HMF that is followed by etherification to the 5-EMF product.
The reaction system is effective for glucose transformation and has
application to biomass-related compounds
N-formyl-stabilizing quasi-catalytic species afford rapid and selective solvent-free amination of biomass-derived feedstocks
\u3cp\u3eNitrogen-containing compounds, especially primary amines, are vital building blocks in nature and industry. Herein, a protocol is developed that shows in situ formed N-formyl quasi-catalytic species afford highly selective synthesis of formamides or amines with controllable levels from a variety of aldehyde- and ketone-derived platform chemical substrates under solvent-free conditions. Up to 99% yields of mono-substituted formamides are obtained in 3 min. The C-N bond formation and N-formyl species are prevalent in the cascade reaction sequence. Kinetic and isotope labeling experiments explicitly demonstrate that the C-N bond is activated for subsequent hydrogenation, in which formic acid acts as acid catalyst, hydrogen donor and as N-formyl species source that stabilize amine intermediates elucidated with density functional theory. The protocol provides access to imides from aldehydes, ketones, carboxylic acids, and mixed-substrates, requires no special catalysts, solvents or techniques and provides new avenues for amination chemistry.\u3c/p\u3