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A series of bifunctional P‐Zr‐SBA‐15 catalysts with Lewis acid and Brønsted acid sites were prepared by modifying mesoporous material SBA‐15 with Zr4+ and phosphate group, which were used in the conversion of xylose and xylan into furfural. The structure and acidic characteristics of the catalyst were analyzed by X‐ray diffraction, Fourier transform infrared spectroscopy, N2 adsorption desorption, scanning/transmission electron microscopy, X‐ray photoelectron spectroscopy, thermogravimetric analysis, NH3 temperature programmed desorption, and pyridine adsorption infrared spectroscopy. The effects of different process parameters on the catalytic performance of the catalyst were studied. when using the xylose and xylan as substrates, the furfural yield were 80.3 % and 68.8 % under the optimal conditions in the H2O(NaCl)/toluene (3/3 mL) biphasic solvent system, respectively, and 52.5 % furfural yield was obtained using xylose as substrate in aqueous system. In addition, the catalyst has good thermal stability and easy recovery in the recycling experiment. [ABSTRACT FROM AUTHOR]

Currently, precious metal catalysts or toxic copper-chromium catalysts are widely used in the catalytic hydrogenation of furfural. In this study, the selective hydrogenation of furfural to furfuryl alcohol was performed over alumina-carbon matrix embedded Ni nanoparticles catalyst. The Ni-loaded metal organic framework precursors were synthesized by reverse microemulsion method (water in oil), then the Ni/Al2O3–C catalysts were obtained by pyrolysis under a nitrogen atmosphere. Various characterizations including XRD, XPS, SEM, TEM, TPR, TPD and TG were carried out to reveal the microstructure and chemical composition of the prepared samples. The results showed that the hexagonal platelet structure and the smaller nickel nanoparticle size(~ 8 nm) benefits from the alumina–carbon matrix support, which helped the uniform dispersion and prevented it from accumulation at high temperatures. In addition, the catalyst performance was greatly affected by the calcination conditions and metal loading. At optimized operating conditions, 98.7% conversion of furfural and 92% yield of furfuryl alcohol could be achieved over Ni0.15/Al2O3–C catalyst in the liquid phase hydrogenation reaction with a good reusability. [ABSTRACT FROM AUTHOR]

Aqueous-phase processing of biomass-derived furfural is one of the promising ways to convert biomass into useful chemicals. Supported metal catalysts are crucial in the aqueous-phase hydrogenation of furfural. Understanding the effect of acid and basic properties of supports on the performance of the catalysts will help understand the reaction pathways and develop more efficient catalysts. Here, a series of Cu-based catalysts with different supports (Al2O3, ZnO, SiO2, MgO, and ZSM-5) have been investigated in hydrogenation of furfural in aqueous phase. The properties of the supports have been characterized by X-ray diffraction, N2 adsorption-desorption, transmission electron microscope, H2 temperature-programmed reduction, and CO2 and NH3 temperature-programmed desorption. The results show that pure acid support leads to the formation of oligomers and pure basic support results in furfuryl alcohol as the main product. And the mass balance in reaction system catalyzed by Cu-based catalysts with higher acidity amount is lower. © 2017 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Liquid phase and one-step reaction for furfural (FFR) hydrogenated to tetrahydrofurfuryl alcohol (THFA) was conducted by employing noble metal-absence and toxicity-free, bimetallic Ni-Co catalysts. The bimetallic Ni-Co catalysts with different molar ratio of Ni to Co and two monometallic catalysts (Ni, Co) were synthesized by conventional incipient-wetness impregnation method with short channeled SBA-15 as support. Among these catalysts, highly selective hydrogenation of FFR to THFA was attained over Ni-Co/SBA-15 catalysts. The impact of molar ratio of Ni/Co was studied with a fixed Ni loading (10 wt %) in bare support. The samples were characterized by N 2 sorption, XRD, XPS, H 2 -TPR, SEM, TEM and CO chemisorption. The results confirmed that the reducibility of Ni-catalysts can be improved by incorporating Co metal and revealed that appropriate amount of spinel NiCo 2 O 4 oxides is favorable to uniform and high dispersion of Ni 0 and CoO over short channeled SBA-15, which would be benefit for the catalytic performance. For catalytic activity investigation, other four mesoporous SiO 2 materials (MCM-41, MCM-4, MCF-2 and common SBA-15) were employed as supports to investigate the effect on the hydrogenation of FFR and the reaction parameters including the reaction temperature, initial of H 2 pressure, reaction time and the reusability of the catalysts were also studied. 100% of FFR conversion and 92.1% of THFA selectivity were achieved at 90 °C, 50 bar of initial H 2 and 2.0 h over catalyst Ni-Co/SBA-15 when the molar ratio of Ni to Co was 0.67. [ABSTRACT FROM AUTHOR]

We present here a study of the production of furfural from xylose and wheat straw using the chromium phosphate (CrPO 4 ) with Lewis and Brønsted acidity as a highly efficient catalyst in the water/tetrahydrofuran (THF) biphasic system. The effects of various reaction parameters including reaction temperature, reaction time, system, and catalyst dosage were explored to evaluate the product yield. Under CrPO 4 catalysis, an excellent furfural yield could reach 88% from the xylose at 160 °C for 60 min. Meanwhile, 67% furfural and 32% 5‑hydroxymethylfurfura (HMF) were simultaneously achieved from wheat straw at 180 °C for 90 min. Mechanistic studies suggested that the perfect catalytic activity of CrPO 4 was due to its inherent bifunctional catalysis activity. It was found that the CrPO 4 was easily to be recovered and a great catalytic activity was available after four cycles, which not only contributed to a sustainably reduced energy consumption on catalyst recovery, but also reduced the concerns associated with toxic chromium element. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuCo bimetallic catalyst was derived from Co-doped Cu-BTC metal organic frameworks. • Synthesized CuCo/C catalyst is very active and stable in conversion of furfural to furfuryl alcohol. • The doping of cobalt helps the dispersion of copper and the thermolysis temperature has an impact on chemical states of copper and cobalt. In this study we report an efficient CuCo bimetallic catalyst with highly dispersed CuCo-based mixed metal/metal oxide on porous carbon matrix for the hydrogenation of furfural to furfuryl alcohol. The catalyst is derived from Co-doped Cu-BTC metal-organic frameworks (MOFs) by thermolysis in nitrogen atmosphere at temperatures ranging from 773 K to 1073 K. The best catalytic performance is achieved when cobalt to copper molar ratio is 0.4 and the precursor is calcined at 873 K. The characterization of prepared catalytic materials is done by multi-techniques including XRD, XPD, SEM, TEM, TG and BET analysis. The sum of their results reveal that the doping of cobalt helps the dispersion of nanoparticles of copper and cobalt and thermolysis temperature has an impact on both the particle size and the chemical states. The resulting catalyst CuCo 0.4 /C-873 shows 98.7% furfural conversion and 97.7% furfuryl alcohol selectivity in ethanol solvent with good stability which is better than most reported catalysts. [ABSTRACT FROM AUTHOR]

CuNi bimetallic nanoparticles embedded in carbon matrix (CuNi@C) were synthesized and applied in the selective conversion of biomass-derived furfural to cyclopentanone. The catalysts were prepared directly from thermolysis of Cu-based metal–organic frameworks (MOFs) impregnated with nickel nitrate. Compared with traditional precipitation method, relatively high surface area (91.6 m 2 /g) and nano-sized (about 15 nm) metallic copper and nickel particles can be obtained when molar ratio of nickel to copper was 0.5. Furthermore, the porous carbon matrix can not only act as a supporter but prevent the accumulation of metal particles. By varying the molar ratio of nickel to copper, CuNi 0.5 @C shows best catalytic performance (99.3% conversion of furfural and 96.9% yield of cyclopentanone) at optimum conditions (130 °C, 5 h, 5 MPa) attributed to the above mentioned properties. In addition, the CuNi 0.5 @C can be reused four times with good activity and stability. Hence, current work presents a new and facile method to prepare CuNi bimetallic catalysts which has a brilliant performance in catalytic conversion of furfural to cyclopentanone. [ABSTRACT FROM AUTHOR]