Back to Search Start Over

Synergistic effects between Cu and Ni species in NiCu/γ-Al2O3 catalysts for hydrodeoxygenation of methyl laurate.

Authors :
Miao, Caixia
Zhou, Guilin
Chen, Shuang
Xie, Hongmei
Zhang, Xianming
Source :
Renewable Energy: An International Journal. Jun2020, Vol. 153, p1439-1454. 16p.
Publication Year :
2020

Abstract

Cu was introduced into Ni/γ-Al 2 O 3 to prepare mesoporous Ni x Cu y /γ-Al 2 O 3 catalysts with different Ni and Cu contents. H 2 -TPR, XRD, BET, H 2 -TPD, and in-situ XPS were used to study the physicochemical properties of the prepared Ni x Cu y /γ-Al 2 O 3 catalysts. The catalytic performances of Ni x Cu y /γ-Al 2 O 3 catalysts were evaluated by methyl laurate catalytic hydrodeoxygenation (HDO) reaction. The Ni x Cu y O/γ-Al 2 O 3 precursors can be reduced to Ni0, Cu0, and NiCu alloy active species by H 2 at 420°C. Formed NiCu alloy can effectively promote the electronic effect between Ni and Cu, and enhance the adsorption and activation abilities of the corresponding catalyst for the reactant molecules. The Ni active sites preferentially catalyzes the decarbonylation/carboxyl (DCO) reaction in the deoxygenation of methyl laurate, while the HDO pathway is predominant on the Cu active sites. The deoxygenation pathway obviously changes from DCO to HDO at the mole ratio of Ni/Cu lower than 3/7, and the main deoxygenation products change from C 11 to C 12 alkane. At the H 2 /Oil ratio of 500N, the space velocity (SV) of 1.5 h−1, H 2 pressure(P) of 2 M Pa, and the reaction temperature of 380°C, the Ni 3 Cu 7 /γ-Al 2 O 3 catalyst shows the best methyl laurate DCO properties. And methyl laurate conversion and the main deoxygenation products C 11 alkane selectivity can reach 98.3 and 87.4%, respectively. Moreover, Ni 3 Cu 7 /γ-Al 2 O 3 catalyst also exhibits good stability. The introduction of Cu into the Ni based catalyst can enormously improve the dispersion of Ni0, Cu0, and NiCu alloy active components. Meanwhile, formed NiCu alloy can also effectively promote the electronic effect between Ni and Cu. The main deoxygenation pathway of methyl laurate and the product selectivity can be directly affected by the content of Ni and Cu active components in the prepared catalysts. The prepared Ni x Cu y /γ-Al 2 O 3 catalysts present superior catalytic hydrodeoxygenation performance and good use stability. Image 1 • The deoxygenation pathway of methyl laurate can be affected by the content of Ni and Cu active components. • Formed NiCu alloy can effectively promote the electronic effect between Ni and Cu. • Developed mesoporous structure and highly dispersed Ni, Cu, and NiCu alloy are beneficial for hydrodeoxygenation. • Ni x Cu y /γ-Al 2 O 3 catalysts present superior methyl laurate hydrodeoxygenation performance and good stability. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
09601481
Volume :
153
Database :
Academic Search Index
Journal :
Renewable Energy: An International Journal
Publication Type :
Academic Journal
Accession number :
142537814
Full Text :
https://doi.org/10.1016/j.renene.2020.02.099