Thermocatalytic decomposition of methane using activated carbon: Studying the influence of process parameters using factorial design

The thermocatalytic decomposition of methane over activated carbon (AC) is proposed as a potential alternative for the production of hydrogen. The experiments were divided into two parts; the first part was conducted using thermogravimetric analyzer (TGA) while the second part was conducted in a bench-scale unit. For the first part, the research objective is to study the main and interaction effects of decomposition temperature (800–950 °C) and methane partial pressure (0.03–0.63 atm) on the initial specific rate of carbon formation by using statistical method. The experiments were carried out as a general full factorial design consisting of 20 experiments. Quadratic model was developed for initial specific rate of carbon formation in term of temperature and methane partial pressure using response surface methodology. The model’s results show that not only the effects of the main parameters are important, but also the interaction effects between them are significant. For the second part, the main effects of decomposition temperature (775–850 °C) and AC weight (20–120 g) on the initial rate of methane decomposition by using the analysis of variance (ANOVA) were investigated. The results showed that AC weight has higher mean effects than decomposition temperature on the initial rate of methane decomposition.

► First time to study the main and interaction effects of process parameters on hydrogen production from methane decomposition. ► Using TGA, the model’s results show that the main parameters and the interaction effects between them are significant. ► The R2 value of Quadratic model equation shows a good fit of the model with experimental data. ► Using a bench-scale unit, the weight of catalyst has higher mean effects than temperature on rate of methane decomposition.