Abstract: A method and apparatus for the pyrolytic destruction or synthesis of gases via a highly tunable combination of radio frequency heating and electron beam irradiation is disclosed. The method is appropriate for destroying toxic gases emanating from hazardous wastes and for synthesizing new molecules from the molecules of a gas. The method is also appropriate for creating scavenger gases and hot gases with large enthalpy for use in sterilization procedures, for example. Embodiments are disclosed employing inductive or direct waveguide/cavity coupling of radio frequency power to the gas. In embodiments of the invention, magnetic fields are used to modify the paths of the electrons in the beam to facilitate tuning and improve the energy efficiency of the system. In a two-stage system, solid and/or liquid wastes are first heated in order to vaporize the toxic materials.