An efficient bifunctional Ni-Nb2O5 nanocatalysts for the hydrodeoxygenation of anisole

The Ni-Nb2O5 nanocatalysts have been prepared by the sol-gel method, and the catalytic hydrodeoxy-genation (HDO) performance of anisole as model compound is studied. The results show that Nb exists as amorphous Nb2O5 species, which can promote Ni dispersion. The addition of Nb2O5 increases the acid-ity of the catalyst. However, when the content of niobium is high, there is an inactive Nb-Ni-O mixed phase. The size and morphology of Ni grains in catalysts are different due to the difference of Nb/Ni molar ratio. The Ni0.9Nb0.1 sample has the largest surface area of 170.8 m(2).g(-1) among the catalysts prepared in different Nb/Ni molar ratios, which is mainly composed of spherical nanoparticles and crack pores. The HDO of anisole follows the reaction route of the hydrogenation HYD route. The Ni0.9Nb0.1 catalyst dis-played a higher HDO performance for anisole than Ni catalyst. The selectivity to cyclohexane over the Ni0.9Nb0.1 sample is about 10 times that of Ni catalyst at 220 degrees C and 3 MPa H-2. The selectivity of cyclo-hexane is increased with the increase of reaction temperature. The anisole is almost completely trans-formed into cyclohexane at 240 degrees C, 3 MPa H-2 and 4 h. (C) 2022 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

Automated summary

The Ni-Nb2O5 nanocatalysts prepared by the sol-gel method were investigated for their catalytic hydrodeoxy-genation (HDO) performance of anisole. The addition of Nb2O5 increased the acidity of the catalyst and promoted Ni dispersion, but a high niobium content resulted in the formation of an inactive Nb-Ni-O mixed phase. By adjusting the Nb/Ni molar ratio, the size and morphology of Ni grains in the catalysts were varied. Among the catalysts prepared at different Nb/Ni molar ratios, the Ni0.9Nb0.1 sample showed the largest surface area, mainly composed of spherical nanoparticles and crack pores. The Ni0.9Nb0.1 catalyst exhibited higher HDO performance for anisole and higher selectivity to cyclohexane compared to Ni catalysts. The selectivity of cyclohexane increased with the increase of reaction temperature, reaching almost complete conversion of anisole to cyclohexane at 240 degrees C, 3 MPa H-2, and 4 hours.