A preparation method of a polyurethane resin including the following steps is provided. A liquid polyamine compound is placed in a continuous reaction system, and the liquid polyamine compound is circulated in the continuous reaction system. A solid bis(cyclic carbonate) and a solid catalyst are placed in the continuous reaction system to mix the solid bis(cyclic carbonate), solid catalyst, and liquid polyamine compound to form a heterogeneous mixture. The heterogeneous mixture is heated in the continuous reaction system in a microwave manner, such that the heterogeneous mixture reacts to form a polyurethane resin.

The present invention relates to a single mode or single dominating mode microwave reactor, a single dominating mode microwave reactor system and a method of producing fuel, such as biofuel.

A combination for carrying out microwave assisted reactions is disclosed, such as acid digestion and solvent extraction. The combination includes a microwave transparent pressure-resistant reaction vessel and a flexible film fluoropolymer liner inside the reaction vessel. The flexible film liner has a size and shape that substantially conforms to the inner walls of the reaction vessel. A pressure-relief closure is positioned on the reaction vessel and the flexible film liner, and an infrared temperature detector that operates in wavelengths (frequencies) to which both the reaction vessel and the flexible liner are transparent, so that an exact fit and conductive heating to the outside of the reaction vessel are not required.

A microwave heating system comprises a bowl, dome and rotor device. The dome is fit to the bowl. The bowl and dome form a volume. The bowl is connected to a microwave source such that a microwave field is supplied to the volume. The microwave field is attenuated in a region between the rotor device and the dome compared to a region between the bowl and the rotor device. The rotor device is rotatably supported by the bowl and supports a reaction vessel. The rotor device includes a base plate with a through-hole and a tubular member that receives the reaction vessel. The base plate and tubular member are metal. The rotor device is coupled to the base plate so that a longitudinal axis of the tubular member passes through the through-hole.

A fluid treatment apparatus is described for the treatment of a fluid substance having multiple component substances to control levels of one or more particular component substances. The apparatus has a reactor chamber; a fluid inlet adapted to provide fluid communication from an external supply of a fluid substance to be treated to said reactor chamber whereby said fluid substance may pass into and through said reactor chamber; a fluid outlet adapted to provide a fluid communication from said reactor chamber whereby said fluid substance may pass from said reactor chamber; at least one first electromagnetic radiation (EMR) waveguide, having at least one first waveguide input port operably coupled within said reactor chamber and adapted to couple electromagnetic radiation of a predetermined first wavelength to a fluid substance passing through said reactor chamber. A method for the treatment of a fluid substance is also described.

A substance treatment apparatus includes an RF signal source, power detection circuitry, a controller, and a transmission path between the RF signal source and a first electrode that radiates electromagnetic energy into a chamber. The RF signal source includes a solid-state amplifier that generates an RF signal. The power detection circuitry detects reflected signal power along the transmission path. Based on the reflected signal power, the controller modifies values of variable components within an impedance matching network electrically coupled along the transmission path to adjust a magnitude of the reflected signal power. The impedance matching network may have a double-ended input connected to a balun, and a double-ended output connected to the first electrode and to a second electrode. Alternatively, the impedance matching network may have a single-ended input connected to the RF signal source, and a single-ended output connected to the first electrode. The second electrode may be grounded.

A Traveling Wave Reactor (TWR) includes an inner microwave-transparent tube including an inlet and an outlet; an outer resonant tube surrounding a section of the microwave-transparent tube; a microwave source operable to provide microwave radiation to the resonant tube, wherein the microwave radiation creates a traveling microwave field in the resonant tube; and a tube rotator operable to rotate the microwave-transparent tube. A method for H.sub.2S treatment includes introducing a gas comprising H.sub.2S into a Traveling Wave Reactor (TWR), wherein the TWR includes a microwave source and a microwave-transparent tube including a catalyst bed; contacting the gas with the catalyst bed; and irradiating the catalyst bed with microwaves emitted by the microwave source, thereby activating a conversion of H.sub.2S.

A vessel system for high-pressure reactions is disclosed. The system includes a plugged polymer cylinder reaction vessel with a pressure vent opening extending radially through the wall of the reaction vessel and a supporting frame into which the vessel is received. Complementing keying structure elements on the vessel and on the frame limit the orientation of the reaction vessel in the supporting frame and the radially extending vent opening to a defined single position.

A microwave reactor constructed to produce a homogeneous heat distribution across the body of the microwave reactor subsequent exposure to microwave irradiation. The microwave reactor includes a body having an exterior wall transparent to microwave irradiation. A microwave sensitized element layer is adjacent the exterior wall and is comprised of a carbide mixture wherein the carbide mixture includes a carbide mixed with either a metal oxide, a ferrite or a nitride. The carbide mixture is in granular form wherein the carbide has a larger particle size than the other component. The microwave sensitized element layer further includes a metal layer that extends the length thereof. The metal layer is positioned in various arrangements within or adjacent to the carbide mixture. The body further includes an inner layer adjacent to the microwave sensitized layer opposite the exterior wall. The inner layer is transparent to microwave irradiation.

A preparation method of a polyurethane resin including the following steps is provided. A liquid polyamine compound is placed in a continuous reaction system, and the liquid polyamine compound is circulated in the continuous reaction system. A solid bis(cyclic carbonate) and a solid catalyst are placed in the continuous reaction system to mix the solid bis(cyclic carbonate), solid catalyst, and liquid polyamine compound to form a heterogeneous mixture. The heterogeneous mixture is heated in the continuous reaction system in a microwave manner, such that the heterogeneous mixture reacts to form a polyurethane resin.