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A new noble metal-free Ni–Co–P/HAP (hydroxyapatite) amorphous alloy catalyst was synthesized by an impregnation-chemical reduction method; the structure and properties of the catalysts were characterized by XRD, SEM, BET, XPS and DSC. Based on the model of the hydrodeoxygenation (HDO) of vanillin to 2-methoxy-4-methylphenol (MMP) with formic acid as a hydrogen source, the catalytic performance of the catalyst was studied. The results found that the Ni–Co–P/HAP catalyst exhibited excellent catalytic activity for the in situ HDO reaction of vanillin compared with Ni–P and Ni–Co–P. The conversion of vanillin could be high to 97.86% with MMP selectivity of 93.97% under optimized reaction conditions. In addition, mechanism studies have shown that the side reaction of carbocation and vanillyl alcohol (HMP) condensation can be effectively reduced with increasing the hydrogenation rate, thereby the selectivity of MMP was effectively increased.

A citric acid ligand assisted self-assembly method is used for the synthesis of ternary mesoporous cerium lanthanum solid solution doped with metal elements (Co, Zr, Mg). Their textural property was characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption, X-ray photoelectron spectroscopy and TPD techniques, and so on. The results of catalytic testing for synthesis of dimethyl carbonate (DMC) from CH3OH and CO2 indicated that the DMC yield reached 316 mmol/g on Ce-La-Co solid solution when the reaction temperature was 413 K and the reaction pressure was 8.0 MPa. It was found that Co had synergistic effect with La and Ce, doping of Co on the mesoporous Ce-La solid solution was helpful to increase the surface area of the catalyst, promote CO2 adsorption and activation, and improve the redox performance of solid solution catalyst. The conversion of Co2+ to Co3+ resulted in the continuous redox cycle between Ce4+ and Ce3+, and the oxygen vacancy content of the catalyst was increased. Studies have shown that the catalytic performance of Ce-La-Co solid solution is positively correlated with oxygen vacancy content. On this basis, the reaction mechanism of DMC synthesis from CO2 and CH3OH on the catalyst was speculated.

The Ni-P amorphous alloy was synthesized by chemical reduction, modified by adding element Co, and characterized by XRD, SEM, XPS and DSC. The hydrodeoxygenation (HDO) performance of the amorphous alloy was investigated by hydrodeoxygenation of vanillin to 2-methoxy-4-methylphenol (MMP). It is shown that the synergy between Ni and Co not only contributes to the reduction of Ni, increases the number of active centers of the catalyst, but also improves the dispersion, disorder and thermal stability of the amorphous alloy. Under the optimized reaction conditions: nCo/(nCo + nNi) (molar ratio) = 0.08, H2 partial pressure of 2.0 MPa, reaction temperature of 150°C, reaction time of 180 min, catalyst dosage of 0.05 g, vanillin conversion and the MMP selectivity can reach 100% and 82.7%, respectively. After 5 cycles of the catalyst, the conversion of vanillin remains 100% and the selectivity of MMP decreases to 68.7%.

A citric acid ligand assisted self-assembly method is used for the synthesis of ternary mesoporous cerium lanthanum solid solution doped with metal elements (Co, Zr, Mg). Their textural property was characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption, X-ray photoelectron spectroscopy and TPD techniques, and so on. The results of catalytic testing for synthesis of dimethyl carbonate (DMC) from CH3OH and CO2 indicated that the DMC yield reached 316 mmol/g on Ce-La-Co solid solution when the reaction temperature was 413 K and the reaction pressure was 8.0 MPa. It was found that Co had synergistic effect with La and Ce, doping of Co on the mesoporous Ce-La solid solution was helpful to increase the surface area of the catalyst, promote CO2 adsorption and activation, and improve the redox performance of solid solution catalyst. The conversion of Co2+ to Co3+ resulted in the continuous redox cycle between Ce4+ and Ce3+, and the oxygen vacancy content of the catalyst was increased. Studies have shown that the catalytic performance of Ce-La-Co solid solution is positively correlated with oxygen vacancy content. On this basis, the reaction mechanism of DMC synthesis from CO2 and CH3OH on the catalyst was speculated.

Carbohydrates were found to have substantial effects on tailoring phase tunable of ionic liquids (ILs) and water. Phase behaviors of 1-alkyl-3-methylimidazolium derivatives [C(n)mim]X (n = 2 to 10, X = Cl(-), Br(-), BF(4)(-))-carbohydrate-H(2)O were systemically investigated. For hydrophilic ILs, 1-alkyl-3-methylimidazolium tetrafluoroborate [C(n)mim]BF(4) (n = 3, 4), the homogeneous aqueous solution can be induced to separate two aqueous phases by addition of carbohydrate. For hydrophobic ILs, [C(n)mim]BF(4) (n = 5 to 10), the mutual solubility with water can be lowered by addition of carbohydrate. While 1-alkyl-3-methyl imidazolium chloride ([C(n)mim]Cl, n = 2 to 10) and 1-alkyl-3-methyl imidazolium bromide ([C(n)mim]Br, n = 2 to 10) aqueous solutions never form aqueous two-phase systems (ATPSs) with carbohydrate in the investigated temperatures ranging from (242.15 to 373.15) K. The high partitioning behavior of phenol in ([C(n)mim]BF(4) (n = 3 to 10) (1) + carbohydrate (2) + H(2)O (3) shows that carbohydrate-tailored {IL + H(2)O} systems are feasible to be used as extraction systems, especially in biological and environmental engineering. (C) 2009 Elsevier Ltd. All rights reserved.

A novel complex Pd(C4H2O4)(C4H8N2)0.5 has been synthesized by solvent thermal synthesis and used as a heterogeneous catalyst for direct synthesis of diphenyl carbonate (DPC) by oxidative carbonylation of phenol. In the reaction system of Pd(C4H2O4)(C4H8N2)0.5/Cu(OAc)2/tetrabutylammonium bromide/hydroquinone/ 4A molecular sieves, the effect of reaction temperature, time and CO pressure on catalytic activity were investigated, and the results revealed that the catalyst could catalyze oxidative carbonylation of phenol effectively. Under suitable reaction conditions of T=90℃, t=4h, p(O2)=0.3 MPa, p(CO)=3.9 MPa and CH2Cl2 as solvent, the turnover number (TON) of diphenyl carbonate can reach about 13.50 (mol-DPC/mol-Pd), which is higher than the TON for pure PdCl2 under the same reaction conditions.