A microwave energy source that generates a microwave energy is disclosed. The microwave energy source has an on-state and an off-state. A control circuit is coupled to the microwave energy source and includes an output to generate a control signal that adjusts a pulse frequency of the microwave energy. A voltage generator applies a non-zero voltage to the microwave energy source during the off-state. A frequency and a duty cycle of the non-zero voltage is based on a frequency and a duty cycle of the control signal. A waveguide is coupled to the microwave energy source. The waveguide has a supply gas inlet that receives a supply gas, a reaction zone that generates a plasma, a process inlet that injects a raw material into the reaction zone, and an outlet that outputs a powder based on a mixture of the supply gas and the raw material within the plasma.

This invention provides an innovative method to manufacture graphene layers or quantities and graphene oxide layers or quantities from graphite, coal slags, asphalt, and other carbon-rich sold materials in nature. The present invention uses controllable microwave irradiation to heat the mixtures of basic material, graphite, or coal slags, or asphalt, or their combinations with ionic liquids and surfactant plus environmentally friendly oxidation agents. This invention can generate the said-products of graphene layers and graphene oxides in a short time period of one second to 300 seconds. The present invention does not involve any concentrated sulfuric acid, nitric acid, nor huge water quantities needed for the purification, unlike the prior art. The as-produced graphene-based materials can be used for preparing conductive films for touch screens, producing graphene carbon fibers and three-dimensional porous graphene nanomaterials, and preparing graphene-based other intelligent nanocomposites for super-light-weight machines and vehicles.

In one aspect, the disclosure relates to relates to heterogeneous catalysts useful for the synthesis of ammonia under microwave irradiation, processes for preparing the disclosed heterogeneous catalysts, and processes for synthesizing ammonia using the heterogeneous catalysts with microwave irradiation. In various aspects, the disclosed heterogeneous catalysts comprise: a metal selected from Group 7, Group 8, Group 9, Group 10, Group 11, or combinations thereof; a metal oxide support; and optionally a promoter material. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

Gas streams may be effectively processed using microwave energy in such a way as to significantly reduce processing cost and plant complexity. In the first instance, microwave energy is used to generate a self-catalytic, non-equilibrium plasma, resulting in essentially complete gas reaction at industrial scales of operation. In the second instance, microwave energy is used in combination with conventional catalyst materials to significantly enhance their performance by enabling operation at reduced gas temperatures. In this second instance, the microwave energy may be used either to generate a non-equilibrium plasma or to selectively and directly heat the catalyst material.

A microwave energy source that generates a microwave energy is disclosed. The microwave energy source has an on-state and an off-state. A control circuit is coupled to the microwave energy source and includes an output to generate a control signal that adjusts a pulse frequency of the microwave energy. A voltage generator applies a non-zero voltage to the microwave energy source during the off-state. A frequency and a duty cycle of the non-zero voltage is based on a frequency and a duty cycle of the control signal. A waveguide is coupled to the microwave energy source. The waveguide has a supply gas inlet that receives a supply gas, a reaction zone that generates a plasma, a process inlet that injects a raw material into the reaction zone, and an outlet that outputs a powder based on a mixture of the supply gas and the raw material within the plasma.

Apparatuses and methods are provided for applying radio frequency (RF) energy from a source of electromagnetic energy to an object in an energy application zone. At least one processor may be configured to acquire information indicative of electromagnetic energy loss associated with at least a portion of the energy application zone. The processor may be further configured to determine a weight to be applied to each of a plurality of electromagnetic field patterns each having a known electromagnetic field intensity distribution and cause the source to supply each of the plurality of electromagnetic field patterns to the energy application zone at the determined weights.

A microwave heating method using a microwave, including: controlling a frequency of the microwave, to form a single-mode standing wave; disposing an object to be heated in a magnetic field region where a strength of a magnetic field formed by the single-mode standing wave is uniform and maximum; and heating the object to be heated by magnetic heat generation by magnetic loss caused by an action of the magnetic field of the magnetic field region, and/or induction heating by an induced current generated in the object to be heated due to the magnetic field of the magnetic field region.

In a system and process for selectively purifying various pharmacologically-relevant components of a source plant such as cannabis, an initial step provides a low-temperature, robust essential oil/terpene capture that also dehydrates and decarboxylates the starting productfresh raw cannabisby means of a vacuum-assisted microwave distillation process. By doing the terpene capture under vacuum distillation temperature may be kept low. The low distillation temperature maximizes yields of thermally-sensitive components such as terpenes and cannabinoids. The system includes an oil/water separator configured to prevent leakage of ambient air into the system.

A microwave microstrip resonator apparatus including a housing; a resonator within the housing; an output conductor within the housing and spaced apart from the resonator so as to define a capacitive gap therebetween; a reaction vessel configured to reside with the capacitive gap; and a power supply coupled to the resonator whereby contents within the reaction vessel are heated when energy is supplied to the resonator by the power supply. A mass spectrometer may also be coupled to an outlet end of the reaction vessel such that the contents within the reaction vessel are, simultaneously, delivered to the mass spectrometer for analysis.

A microwave thermosolar method and device used in a tubular reactor (110) includes a conveyor for substrates defined as materials thus conveyed. According to this method, a step is provided for circulating an electric current in the conveyor in order to produce heat in this conveyor by Joule effect and optionally to cause, in the substrates, at least some of the following: curing, pyrolyses, gasifications, fusions and chemical reactions including oxidation-reduction reactions, under the action of the electric current.