Effect of CoMo metal loading on H2 and CNTs production from biogas by integrative process

Effect of CoMo metal loading to MgO (1, 5, 30 and 50 wt%) on conversion of biogas by an integrative process was investigated at 900 °C under atmospheric pressure. The integrative process combines the direct methanation of CO 2 in biogas and the CH 4 decomposition to upgrade biogas to CH 4 and decompose to hydrogen and carbon nanotubes. Methane dissociative reaction is governed by the concentration of active metals on the catalyst surface, while DRM reaction is suppressed. The 30 wt%CoMo catalyst shows the optimal loading for production of high-purity H 2 (>90v/v%) and high yield of MWCNTs (2.33 gCNT/gCat-h) with 100%CO 2 conversion and 95%CH 4 conversion. Meanwhile, 1 wt%CoMo catalyst provided the single-walled CNTs with diameter of 2.5 nm, high surface area of 165 m 2 /g and high graphitization of I G /I D = 6.14. • The 100%CO 2 conversion and 95%CH 4 conversion of biogas was obtained. • The hydrogen with 90%purity was produced from biogas. • The 30 wt%CoMo catalyst shows the optimum catalyst. • The high value-added MWCNTs was obtained. • The 1 wt%CoMo catalyst produced SWCNTs.