No abstract

The stability test results for the CaO, CeO2@CaO-60 and CeO2–CaO-60 catalysts for biodiesel production.

The in-situ hydrodeoxygenation of bio-derived phenol is an attractive routine for upgrading bio-oils. Herein, an active trimetallic Ni-Cu-Co/Al2O3 catalyst was prepared and applied in the in-situ hydrodeoxygenation of bio-derived phenol. Comparison with the monometallic Ni/Al2O3 catalyst and the bimetallic Ni-Co/Al2O3 and Ni-Cu/Al2O3 catalysts, the Ni-Cu-Co/Al2O3 catalyst exhibited the highest catalytic activity because of the formation of Ni-Cu-Co alloy on the catalyst characterized by using X-ray powder diffraction (XRD), temperature programmed reduction (TPR), N2 physisorption, scanning electron microscope (SEM), and transmission electron microscope (TEM). The phenol conversion of 100% and the cyclohexane yield of 98.3% could be achieved in the in-situ hydrodeoxygenation of phenol at 240 °C and 4 MPa N2 for 6 h. The synergistic effects of Ni with Cu and Co of the trimetallic Ni-Cu-Co/Al2O3 catalyst played a significant role in the in-situ hydrodeoxygenation process of phenol, which not only had a positive effect on the production of hydrogen but also owned an excellent hydrogenolysis activity to accelerate the conversion of cyclohexanol to cyclohexane. Furthermore, the catalyst also exhibited excellent recyclability and good potential for the upgrading of bio-oils.

The sorption-enhanced steam reforming (SESR) of poplar sawdust pyrolysis oil and acetic acid for high-purity hydrogen production was investigated in this present work. The Ni/CeO2-ZrO2-CaO bifunctional materials with different Ce/Ca ratios were prepared and characterized by the analytic techniques of N2 adsorption–desorption measurement, X-ray diffraction, temperature-programmed reduction, temperature-programmed oxidation, and transmission electron microscopy. The effects of the Ce/Ca ratio in Ni/CeO2-ZrO2-CaO catalysts on the CO2 capture abilities and the catalytic behaviors were also discussed. The Ni/Ce1.2Zr1Ca5 catalyst showed an excellent catalytic performance with a purity of H2 up to about 95% even after 15 consecutive cycles for the SESR of acetic acid. It also exhibited an improved catalytic activity for the SESR of poplar sawdust pyrolysis oil. However, after several SESR operations of bio-oil, the carbon deposits and Ni particles sintering could be found on the surface, which might be the dominant deactivation cause for this catalyst.