A conventional high voltage wire-like plasma cna be greatly enhanced and spread by pulsed microwave to form an umbrella-like plasma contionuously distributed in reactor. By use of this plasma, methanr is directly converted to C2 hydrocarbons at high yield under the condition of atmospheric or higher pressure. The effect of pressure, microwave power, pulse duration, molar ratio of H2/CH4 and flow rate on the methane conversion was investigated. Higher conversion of methane is achieved by proper choice of parameters, and the products only comprise ethylene and acetylene; The molar ratio of C2H2/C2H4 could be adjusted through changing the pressure. With total flow rate of 300 mL/min, H2/CH4 molar ratio of 2, pressure of 0.13 MPa, peak microwave power of 120W, pulse duty factor of 400/400 ms, conversion of methane and yield of C2 could reached up to 59.2% and 52% respectively.

Key words: LOW TEMPERATURE, MICROWAVE, PLASMAS, NATURAL GAS PYROLYSIS, NATURAL GAS, C2 COMPOUNDS