2.3. Catalytic Performance Testing

The catalytic runs were carried out in a fixed-bed reactor operating at atmospheric pressure. The catalysts (200 mg, 160–250 μm) diluted with quartz particles were pre-treated under a 5% O₂/He flow (100 cm³ min⁻¹) at 500 °C for 1 h. The standard reaction mixture was composed of 1%CH₄ and 20%O₂ balanced with He (F_tot = 100 cm³ min⁻¹) corresponding to a weight hourly space velocity (WHSV) of 300 cm³ CH₄ h⁻¹ g⁻¹. The reaction temperature was increased from 200 to 500 °C with a ramp of 1 °C min⁻¹. The thermocouple was positioned at the inlet of the catalyst bed. Additional experiments were performed to study the influence of the addition of water (10%) and CO₂ (10%). The water vapor was fed using a GILSON 307 pump (Gilson Inc., Middleton, OR, USA). The analysis system consisted of a gas chromatograph (Agilent Technologies 490 Micro GC) (Agilent Technologies, Santa Clara, CA, USA) equipped with a TCD detector.