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Molecular interactions of the ternary mixtures of 1-butyl-3-methylimidazolium chloride ([C4C1im]Cl)-water-2, 6-dimethoxyphenol (2, 6-DMP, a phenolic monomer lignin model compound) were investigated in comparison with the [C4C1im]Cl-water binary systems through attenuated total reflection infrared spectroscopy. Results indicated that the microstructures of water and [C4C1im]Cl changed with varying mole fraction of [C4C1im]Cl (xIL) from 0.01 to 1.0. This change was mainly attributed to the interactions of [C4C1im]Cl-water and the self-aggregation of [C4C1im]Cl through hydrogen bonding. The band shifts of C-H on imidazolium ring and the functional groups in 2, 6-DMP indicated that the occurrence of intermolecular interactions by different mechanisms (i.e., hydrogen bonding or π-π stacking) resulted in 2, 6-DMP dissolution. In the case of xIL=0.12, the slightly hydrogen-bonded water was fully destroyed and [C4C1im]Cl existed in the form of hydrated ion pairs. Interestingly, the maximum 2, 6-DMP solubility (238.5 g/100 g) was achieved in this case. The interactions and microstructures of [C4C1im]Cl-water mixtures influenced the dissolution behavior of 2, 6-DMP.

Binary mixtures of 1,3-dialkylimidazolium based ionic liquids (ILs) and water were selected as solvent systems to investigate the solute-solvent and solvent-solvent interactions on the preferential solvation of solvatochromic indicators at 25 °C. Empirical solvatochromic parameters, dipolarity/polarizability (π*), hydrogen-bond donor acidity (α), hydrogen-bond acceptor basicity (β), and Reichardt's polarity parameters (ENT) were measured from the ultraviolet-visible spectral shifts of 4-nitroaniline, 4-nitroanisole, and Reichardt's dye. The solvent properties of the IL-water mixtures were found to be influenced by IL type and IL mole fraction (xIL). All these studied systems showed the non-ideal behavior. The maximum deviation to ideality for the solvatochromic parameters can be obtained in the xIL range from 0.1 to 0.3. For most of the binary mixtures, the π* values showed the synergistic effects instead of the ENT, α and β values. The observed synergy extent was dependent on the studied systems, such as...

An inverse gas chromatographic (IGC) method has been used to measure the solubility parameters (delta2) of organosolv lignin at the absolute temperatures from 333.15 K to 373.15 K. The test probe solvents were n-octane (n-C8), n-decane (n-C10), n-dodecane (n-C12), and n-tetradecane (n-C14). The specific retention volumes of the solvents (Vg0), the molar enthalpy of sorption (deltaH1S), the partial molar enthalpy of mixing at infinite dilution (deltaH1infinity), the molar enthalpy of vaporization (deltaHv), the activity coefficients at infinite dilution (Omega1- infinity), and Flory-Huggins inter action parameters (chi12infinity) between organosolv lignin and probe solvents were obtained. The results showed that the above four probes are poor solvents for organosolv lignin; at the same temperature, the chi12infinity reduced with the increase of the carbon number of probe solvents. The average solubility parameter of organosolv lignin was determined as 19.03 (J x cm(-3))1/2.

A thermodynamic analysis of glycerol steam reforming in the presence of a CO2 adsorbent (CaO) and solid oxygen transfer material (Fe2O3) for high-purity hydrogen production was performed using the Gibbs free energy minimization method. CO in reformate gas was reduced via CO oxidation by Fe2O3 into CO2 coupled with in situ CO2 capture by CaO. The high-purity hydrogen produced without using a downstream reactor has potential application in proton exchange membrane fuel cells (PEMFCs). The influence of temperature (300–1000 °C), pressure (0.1–1.0 MPa), and mole ratios of H2O/glycerol (1–10), CaO/glycerol (0–6), and Fe2O3/glycerol (0–6) on equilibrium gas compositions and carbon formation was evaluated. The produced gas (99.8 mol% H2 and 12.8 ppm CO) was obtained without carbon formation under the optimal conditions (450 °C, 0.1 MPa, CaO/glycerol mole ratio of 3, Fe2O3/glycerol mole ratio of 3 and H2O/glycerol mole ratio of 10), and can be directly used in PEMFCs. However, further optimizations are needed.

The epoxidation of olefins with H 2 O 2 was performed with a tungsten-containing catalyst. This insoluble catalyst forms soluble active species by the action of H 2 O 2 , and when the H 2 O 2 is used up, the catalyst precipitates for easy recycling. Thus, the advantages of both homogeneous and heterogeneous catalysts are combined in one system through reaction-controlled phase transfer of the catalyst. When coupled with the 2-ethylanthraquinone/2-ethylanthrahydroquinone redox process for H 2 O 2 production, O 2 can be used for the epoxidation of propylene to propylene oxide with 85% yield based on 2-ethylanthrahydroquinone without any co-products. This approach avoids the problematic co-products normally associated with the industrial production of propylene oxide.

The effect of inorganic salts on the hydrolysis of starch in a microwave field was investigated and it was found that some inorganic salts can effectively accelerate the acid hydrolysis of starch. The yield of D-glucose reached 111 wt% (equal to the theoretical yield).