A reaction chamber contains catalytic material(s). Tunable microwave source(s) each emit microwave radiation at corresponding time-varying microwave frequency(ies) or at simultaneous multiple different microwave frequencies. Microwave transmission element(s) irradiate the interior volume of the reaction chamber with the microwave radiation, emitted by the microwave source(s), that propagates along the transmission element(s) into the reaction chamber. The reaction chamber is characterized by a maximum temperature variation of a fixed-frequency, steady-state temperature spatial profile that results from irradiation of the reaction chamber by microwave radiation at a substantially fixed microwave frequency and at a reference microwave power level. Irradiation of the reaction chamber at the reference microwave power level by the microwave radiation with the time-varying microwave frequency(ies), or the simultaneous multiple different microwave frequencies, results in a multi-frequency temperature spatial profile having a maximum temperature variation less than the maximum temperature variation of the fixed-frequency, steady-state temperature spatial profile.

Apparatus and method are disclosed for plasma synthesis of graphitic products including graphene. A plasma nozzle is coupled to a reaction chamber. A process gas is supplied to the plasma nozzle, the process gas comprising a carbon-containing species. Radio frequency radiation is supplied to the process gas within the plasma nozzle, so as to produce a plasma within the nozzle in use, and thereby cause cracking of the carbon-containing species. The plasma nozzle is arranged such that an afterglow of the plasma extends into the reaction chamber. The cracked carbon-containing species also passes into the reaction chamber, and the cracked carbon-containing species recombines within the afterglow, so as to form the graphitic products including graphene.

A chemical reaction method having steps of preparing a chemical reaction apparatus by partitioning an inside of a horizontal flow reactor into multiple chambers by multiple partition plates, and flowing a liquid horizontally with an unfilled space being provided thereabove, generating microwaves with a microwave generator, and transmiting the microwaves, with at least one waveguide, to the unfilled space in the reactor. Also forming a top portion of the partition plates act as a weir, inclining the reactor such that, in each of the chambers, a weir height on the inlet side is higher than a weir height on the outlet side by at least an overflow depth at the partition plate on the outlet side, flowing content over each of the partition plates inside the reactor, and configuring the weir heights of the partition plates in the reactor are the same in a state where the reactor is not inclined.

The disclosure provides several pyrolysis reactor configurations and associated methods for generating pyrolysis products (e.g., oil, gas, and/or char) from organic feedstock.

An instrument and method for high pressure microwave assisted chemistry are disclosed. The method includes the steps of applying microwave radiation to a sample in a sealed vessel while measuring the temperature of the sample and measuring the pressure generated inside the vessel and until the measured pressure reaches a designated set point, opening the vessel to release gases until the pressure inside the vessel reaches a lower designated set point, closing the vessel, and repeating the steps of opening the vessel at designated pressure set points and closing the vessel at designated pressure set points to the sample until the sample reaction reaches a designated high temperature. The designated set points can controllably differ from one another as the reaction proceeds. Microwave energy can be applied continuously or intermittently during the opening and closing steps. The apparatus includes a microwave cavity, a microwave transparent pressure resistant reaction vessel in the cavity, a cap on the reaction vessel, a pressure sensor for measuring pressure in the vessel, a temperature sensor, and means for opening and closing the cap at predetermined pressure set points measured by the pressure sensor to release pressure from the vessel.

A system for processing hydrocarbon materials, comprising a hydrocarbon feedstock source; a process gas source; a waveguide; and a reaction tube structure. The process gas source comprises one or more sources of gases selected from the group consisting of helium, argon, krypton, neon, xenon, methane, propane, butane, ethane, acetylene, propylene, butylene, ethylene, carbon monoxide, carbon dioxide, water vapor, hydrogen, and nitrogen. The waveguide comprises a lateral portion comprising housing having a first end portion configured to be connected to a microwave generator, a closed opposite end portion, a primary axis extending from the first end portion to the second end portion, and a central portion having an opening, wherein the central portion has a depth that is smaller than a corresponding depth of the first end portion and the second end portion, and a coaxial portion having a first end portion connected to the opening and a lateral dimension that is perpendicular to the primary axis. The reaction tube structure comprises an outer wall made of a dielectric material, and is configured such that when hydrocarbon feedstock from the feedstock source and process gas from the process gas source are fed into the reaction tube structure and microwaves are received in the waveguide, one or more surface waves are propagated in the reaction tube structure to form a plasma within the reaction tube structure and cause the feedstock and process gas to react and form into a product stream, and wherein the reaction tube structure has a lateral dimension that is perpendicular to the lateral portion and parallel to the coaxial portion, and the reaction tube structure is connected to a second end of the coaxial portion.

A microwave reduction furnace including a reaction furnace provided with a refractory chamber of silica or silicon carbide for storing a material therein, a supply section for supplying the material into the refractory chamber, the material being a mixture of a silica powder and a graphite powder or a mixture of a silica powder, a silicon carbide powder and a graphite powder, a discharge section for discharging molten silicon, obtained through reduction, out of the chamber, and a microwave oscillator for outputting microwave toward the refractory chamber in the reaction furnace with a degree of directionality by virtue of a helical antenna or a waveguide.

A system for converting hydrocarbon materials into a product includes a hydrocarbon feedstock source, a process gas source, an energy generator, and a cylindrical reaction chamber. The reaction chamber has a conductive inner surface that forms a resonant cavity. The resonant cavity is configured to support a standing TM010 electromagnetic wave. The reaction chamber is also configured to receive feedstock from the feedstock source, process gas from the process gas source, and convert the feedstock into a product stream in the presence of the TM010 electromagnetic wave.

A method of converting carbon containing compounds such as coal, methane or other hydrocarbons into a liquid hydrocarbon fuel utilizes a high pressure, high temperature reactor which operates upon a blend of a carbon compound including CO.sub.2 and a carbon source, a catalyst, and steam. Microwave power is directed into the reactor. The catalyst, preferably magnetite, will act as a heating media for the microwave power and the temperature of the reactor will rise to a level to efficiently convert the carbon and steam into hydrogen and carbon monoxide.

Embodiments of the present invention are directed to apparatus and methods for converting carbon dioxide and/or methane into higher alkanes and hydrogen gas in a single reaction chamber using a catalyst and microwave radiation.