Hydrodeoxygenation of phenolic compounds to cycloalkanes over supported nickel phosphides

Abstract SiO 2 , HZSM-5 and Al 2 O 3 were used to support nickel phosphides to prepare hydrodeoxygenation (HDO) catalysts. The nickel loading was kept at 20 wt% while the Ni/P molar ratio was varied among 3, 2, and 1 in the preparation by incipient wetness impregnation. XRD characterization revealed that Ni 3 P, Ni 12 P 5 , and Ni 2 P as the major crystal phases were obtained at Ni/P ratio of 3, 2, and 1, respectively, on SiO 2 and HZSM-5. When Al 2 O 3 was used as the support, nickel metal rather than nickel phosphides was generated. Among SiO 2 -supported nickel phosphides, Ni 3 P exhibited highest hydrogenation activity and catalytic performance in phenol HDO. Ni 3 P/HZSM-5 showed the high catalytic performance in HDO of phenol as well as catechol and o-cresol, with Ni 3 P as the hydrogenation site and the acid sites in HZSM-5 zeolite as the dehydration site. The strong acidity in HZSM-5 also facilitated the isomerization of cycloalkanes at elevated temperatures.