Catalytic steam reforming of n-dodecane over high surface area Ce0.75Zr0.25O2 supported Ru catalysts

A high surface area (HSA) Ce 0.75 Zr 0.25 O 2 (CZ) support was synthesized by hydrothermal synthesis method with assistance of surfactant (cetyltrimethyl ammonium bromide , CTAB), and then 2.0 wt% Ru was impregnated on it to obtain a steam reforming catalyst for n-dodecane. The surface area of Ru/HSA-CZ catalyst is 107.6 m 2  g −1 , which is ca. three times higher than that prepared through the sol-gel (sg) method (34.3 m 2  g −1 , Ru/CZ-sg) and ca. 40% higher than that without CTAB (76.7 m 2  g −1 , Ru/CZ-wo). Catalytic steam reforming of n-dodecane, shows the completely conversion of n-dodecane over Ru/HSA-CZ and slightly drops about 6% (650 °C, LHSV = 12 mL/g h, S/C = 4, time on stream = 7 h) while 81% and 70% were observed for the Ru/CZ-wo and Ru/CZ-sg but with twice (or triple) deactivation rates. The possible reason for observed better performance of Ru/HSA-CZ should be attributed to the high metal dispersion of Ru over HSA-CZ, and the favorable Ru-support interaction as evidenced by H 2 -Temperature programmed reduction (H 2 -TPR), and high redox ability of high surface area Ce 0.75 Zr 0.25 O 2 support thanks to high Ce 3+ content. Further steam reforming of n-dodecane over Ru/HSA-CZ at higher LHSV (750 °C, LHSV = 36 mL/g h, S/C = 4) exhibits completed conversion and without significant deactivation.