The embodiments disclosed herein are directed to systems, methods, and devices for pyrolysis of methane in a microwave plasma for hydrogen production and structured carbon powder. Some methods are directed to producing a structured carbon powder using a microwave generated plasma comprising injecting a plasma gas comprising methane (CH.sub.4) into a liner, the liner in communication with a microwave waveguide; propagating microwaves through the microwave waveguide, the microwaves generated using a microwave generator; and generating a microwave plasma by contacting the plasma gas with the microwaves.

Plasma generators and methods of generating plasma are disclosed. Electrodes in a reaction zone are energized by a high voltage power source that is electrically insulated from the electrodes. A first conductor array, preferably a coil, is electrically coupled to the power source and electrically insulated from the electrodes. A second conductor array, preferably a coaxial coil nested within the first conductor array, is electrically coupled to the electrodes. Electromagnetic induction between the first conductor array and the second conductor array is used to energize the electrodes and generate a plasma in the reaction zone. One or more microwaves are further directed at the plasma to form microwave plasma, either in parallel or in series. Such plasmas are used to reform a hydrocarbon feedstock into low C hydrocarbons, carbon, or hydrogen. Plasma generators combining induction plasma with serial microwave plasmas are further contemplated.

An apparatus for treating gaseous pollutant with plasma comprises a microwave source generating a microwave oscillation; a waveguide component coupled to the microwave source; and a resonant cavity coupled to the waveguide component, the microwave oscillation is substantially propagated toward a waveguide direction, the resonant cavity comprises a first chamber and a second chamber, the waveguide direction is substantially parallel to a reference axis defined in the first chamber, the first chamber has an inner wall surrounding the reference axis, the inner wall comprises a first inner wall obliquely inclined toward the reference axis and a second inner wall substantially parallel in respect to the reference axis relatively, an area of the first inner wall is larger than that of the second inner wall so that the first chamber has a tapered space, and the microwave oscillation interacts with an ignition gas in the second chamber to generate a torch.

The present technology is directed to a system for controlling the electron energy distribution function in an atmospheric and near-atmospheric low-temperature plasma by subjecting the generated plasma to a repetitive nanosecond-pulsed voltage that is completely decoupled from the means that generated the plasma (i.e., decoupled from an electron-beam). The repetitive nanosecond-pulsed voltage generates a nanosecond-pulsed electric field that affects the energy of the electrons in the plasma without affecting the energy of the ions.

There is a cold atmospheric plasma generator configured to receive air as input substance and expel RONS, Reactive Oxygen and Nitrogen Species, suitable for being inhaled by living beings as output substance, and respiratory device that integrates said cold atmospheric plasma generator.

An arc plasma reactor includes a cylindrical surface, a gas inlet, an arc generation part, a catalyst filling part, and a gas outlet. The gas inlet is formed on the cylindrical surface and injects gas at an angle of 30 degrees () to 90 with respect to a long axis of the arc plasma reactor. The arc generation part includes a high voltage electrode disposed inside the arc plasma reactor and a ground electrode disposed on an inner wall of the arc plasma reactor. The catalyst filling part is disposed in an area outside the arc generating part, on an opposite side of the gas inlet, and an inside diameter of the arc plasma reactor in an area where the high voltage electrode is disposed is less than an inside diameter of the arc plasma reactor in an area where the catalyst filling part is disposed.

A gas treatment system includes a first scrubber, a regenerative catalytic oxidizer (RCO) that treats gas that passes through the first scrubber, a second scrubber that treats the gas that passed through the regenerative catalytic oxidizer, and a dielectric barrier discharge (DBD) plasma reactor that treats the gas that passed through the second scrubber. The regenerative catalytic oxidizer includes a two-bed regenerative catalytic reactor.

There is provided a dielectric barrier electrical discharge apparatus, system and method. The apparatus comprises at least two electrodes arranged in use to provide at least one anode and at least one cathode an electric field thereby being establishable therebetween, the at least two electrodes being separated to allow a fluid to be present between the electrodes in use. At least one of the electrodes has a dielectric portion connected to at least part of said electrode, and a sub-macroscopic structure is connected to at least one of the electrodes or dielectric portion.

A generator includes a plasma production tube made of a dielectric at least on a surface of the plasma production tube; an antenna that includes a linear conductor and a dielectric that coats the conductor; a high-frequency power supply connected to the antenna; and a gas supply unit that supplies a gas for generating radicals or ions to an interior of the plasma production tube. The antenna is disposed to extend to a vicinity of the other end of the plasma production tube. The antenna is disposed in a groove formed in an axial direction on an inner surface of the plasma production tube. The antenna is disposed in a groove formed in a circumferential direction on an inner surface of the plasma production tube at least in a portion of the vicinity of the other end of the plasma production tube.

A plasma reactor for decomposing a hydrocarbon fluid includes a reactor chamber and a plasma torch attached to a wall of the reactor chamber and including an inner tubular electrode and an outer tubular electrode. A feed lance projecting into the reactor chamber is arranged inside the inner tubular electrode and is displaceable relative to the tubular electrodes by way of a sliding mechanism. A plasma gas outlet for dispensing plasma gas is between the inner tubular electrode and the outer tubular electrode, and an oxidizing fluid outlet for dispensing oxidizing fluid preferably including CO.sub.2 or H.sub.2O is disposed within the inner tubular electrode. Related methodology is also disclosed.