Abstract

n-Ni/SiO2, n-Fe/SiO2 and n-Co/SiO2 nano-catalysts were prepared by co-precipitation cum modified Stöber method and applied for thermocataltytic decomposition of methane in order to investigate their thermal stability and activity to produce greenhouse gas free hydrogen and nano-carbon. Mean particles sizes of produced nano-catalysts obtained from BET analysis are 32.19 nm, 30.26 nm and 49.92 nm, respectively. Temperature programmed methane decomposition were conducted as preliminary catalytic examination and further isothermal analysis were performed at 700  °C, 600 °C and 500 °C. Production of hydrogen at each experimented temperatures and corresponding carbon yield were measured. Among the three catalysts inspected, n-Ni/SiO2 has found as the most efficient one for thermocatalytic methane decomposition. Furthermore, significant catalytic stability was observed with n-Ni/SiO2 and 500 °C and 600 °C. While, the rapid deactivation of the n-Fe/SiO2 and n-Co/SiO2 catalysts are attributed to the particle agglomeration and irregular formation of nano-carbon due to the metal fragmentation. Physical and chemical characteristics of produced nano-catalysts were performed by N2 adsorption-desorption measurement (BET), X-ray diffraction (XRD), transmission electron microscopy (TEM) and hydrogen-temperature programmed reduction (H2-TPR). Produced nano-carbon were inspected with TEM, FESEM and XRD.