*3.4. Catalytic Perfromance*

Methane reforming reaction was accomplished in a fixed-bed tubular stainless-steel micro-reactor (ID = 9 mm) at atmospheric pressure. The reactor system was provided by Process Integral Development (Process Integral Development Eng & Tech SL, Madrid, Spain). Before performing the DRM reaction, a 0.10 g catalyst was activated by H2 flow of 40 mL/min at 700 ◦C for 60 min. N2 gas was then admitted to the reactor for 20 min to remove adsorbed H2 while the catalyst was kept at reaction temperature (700 ◦C). Afterwards, feed gases of CH4, CO2, and N2 were injected at flow rates of 30, 30 and 5 mL/min, respectively. The temperature, pressure and reaction variables were inspected through the reactor panel. A GC (Shimadzu Corp., Kyoto, Japan) unit having a thermal conductivity detector and two columns, Porapak Q and Molecular Sieve 5A, was connected in series/bypass connections in order to have a complete analysis of the reaction products. The following equations were used to calculate the CH4 and CO2 conversions respectively.

$$\% \text{CH}\_4 \text{ conversion} = \frac{\text{CH}\_4 \text{ in} - \text{CH}\_4 \text{ out}}{\text{CH}\_4 \text{ in}} \times 100$$

$$\% \text{CO}\_2 \text{ conversion} = \frac{\text{CO}\_2 \text{ in} - \text{CO}\_2 \text{ out}}{\text{CO}\_2 \text{ in}} \times 100$$
