Oxidative coupling of methane in hysteresis condition

A system for catalytic oxidative coupling of methane, the system comprising:

• a fixed-bed reactor configured to operate at adiabatic condition and receive a stream comprising oxygen and methane;
• and
• a catalyst contained inside of the fixed-bed reactor and configured to catalyze oxidative coupling of the methane in a hysteresis mode,
• wherein the catalyst is in the form of pellets or powders with average particle size ranging from 50 μm and 40 mm, and has a morphological shape selected from the group consisting of cylindric, hollow, spheric, multilobe, and others, and a ratio between an external surface area (A) and an external volume (V) in the range of 100 m−1 and 30000 m−1.