Oxidative coupling of methane systems and methods

A system for generating hydrocarbons having two or more carbon atoms (C2+ hydrocarbons), comprising:

• a methane source that provides methane;
• an oxidant source that provides an oxidant;
• a reaction unit in fluid communication with said methane source and said oxidant source, said reaction unit comprising a catalyst bed that includes at least one oxidative coupling of methane (OCM) catalyst, wherein said OCM catalyst facilitates an OCM reaction using said methane from said methane source and said oxidant from said oxidant source to generate said C2+ hydrocarbons, and wherein said catalyst bed has an inlet zone that is contacted by a bulk gas mixture formed upon entry of said methane from said methane source and said oxidant from said oxidant source into said reaction unit;
• and
• a control unit operably coupled to said reaction unit, wherein said control unit is programmed to:
• (a) maintain a thermal profile across said catalyst bed during said OCM reaction, which thermal profile is characterized by (i) a temperature of said inlet zone being less than about 600° C., and (ii) a maximum temperature within said catalyst bed being greater than about 800° C.;
• (b) maintain a pressure within said reaction unit greater than about 15 pounds per square inch gauge (psig);
• and
• (c) maintain said OCM reaction within said catalyst bed at a methane conversion of at least about 6% and a C2+ hydrocarbon selectivity of at least about 40%.