A method for converting uranium hexafluoride to uranium dioxide includes steps of hydrolysis of UF.sub.6 to uranium oxyfluoride (UO.sub.2F.sub.2) in a hydrolysis reactor (4) by reaction between gaseous UF.sub.6 and dry water vapour injected into the reactor (4), and pyrohydrolysis of UO.sub.2F.sub.2 to UO.sub.2 in a pyrohydrolysis furnace (6) by reaction of UO.sub.2F.sub.2 with dry water vapour and hydrogen gas (H.sub.2) injected into the furnace (6). The hourly mass flowrate of gaseous UF.sub.6 supplied to the reactor (4) is between 75 and 130 kg/h, the hourly mass flowrate of dry water vapour supplied to the reactor (4) for hydrolysis is between 15 and 30 kg/h, and the temperature inside the reactor (4) is between 150 and 250° C.

There is described a method of producing hydrogen and nitrogen using a feedstock gas reactor. Reaction of feedstock and combustion gases in the reactor produces hydrogen and nitrogen through pyrolysis of the feedstock gas. Parameters of the process may be adjusted to control the ratio of hydrogen to nitrogen that is produced such that it may be suitable, for example, for the synthesis of ammonia.

A microwave pyrolysis reactor including an elongated hollow body defining an internal cavity, a bottom body secured to the bottom end of the elongated hollow body, and a top body secured to the top end of the elongated hollow body, the elongated hollow body and the bottom and top bodies form an enclosure for receiving a product to be pyrolyzed, wherein the elongated hollow body includes an elongated wall extending between an internal face and an external face, the elongated wall being provided with at least one fluid receiving cavity for receiving therein a temperature control fluid in order to control a temperature of the product when received in the enclosure, and with the at least one fluid receiving cavity extending at least within a bottom section of the elongated wall adjacent to the bottom body.

Described herein is an improved conversion of nitrous oxide (N.sub.2O) present as a by-product in a chemical process to NO.sub.x which can be further converted to a useful compound or material, such as nitric acid.

Methods and systems for producing vinyl acetate may use flammability limit (FL) formulas with improved efficiencies at more than one location in the vinyl acetate production process. Herein, FLs can be used at one or more of four portions of the vinyl acetate production process: the reactor, the process-to-process heat exchangers, the carbon dioxide removal system, and the ethylene recovery system. Such FLs are functions of operating conditions and include at least one interaction term that represents the interrelation of two or more of the operating conditions (e.g., temperature, pressure, and component concentration) on the FL.

A reactor and method for the conversion of hydrocarbon gases utilizes a reactor (12, 312, 412, 512, 612, 712) having a unique feed assembly with an original vortex combustion chamber (40, 340, 436, 536, 636, 736), a diverging conduit (48, 348, 448, 548, 648, 748), and a cylindrical reactor chamber (40, 340, 436, 536, 636, 736). This design creates a compact combustion zone and an inwardly swirling fluid flow pattern of the feed gases to form a swirling gas mixture that passes through a diverging conduit (48, 348, 448, 548, 648, 748). The feed streams can be introduced into the reactor at any angle (perpendicular, axial, or something between, or a combination of the above forms) with swirling flow components. This provides conditions suitable for efficient cracking of hydrocarbons, such as ethane, to form olefins.

A distillation apparatus for use in microwave-assisted pyrolysis includes a microwave, a pyrolysis reactor, a microwave-absorbent bed, and a condenser. The pyrolysis reactor is located within the microwave and configured to receive a liquid input stream and to output a vapor. The microwave-absorbent bed is located within the pyrolysis reactor that converts microwave energy provided by the microwave to thermal energy to initiate pyrolysis within the pyrolysis reactor, wherein the pyrolysis reactor provides a vapor output. The condenser is configured to receive the vapor output of the pyrolysis reactor and to cool and condense the vapor into a recoverable product.

Provided is a method of producing a silicon compound material, including the steps of: storing a silicon carbide preform in a reaction furnace; supplying a raw material gas containing methyltrichlorosilane to the reaction furnace to infiltrate the preform with silicon carbide; and controlling and reducing a temperature of a gas discharged from the reaction furnace at a predetermined rate to subject the gas to continuous thermal history, to thereby decrease generation of a liquid or solid by-product derived from the gas.

The present invention provides materials for improving the ignition of gaseous reactants in metal catalyzed oxidation reactions comprising a metal catalyst gauze, preferably, a platinum/rhodium catalyst gauze, having in contact therewith, from 0.5 to 1.5 wt. %, based on the weight of the metal catalyst gauze, of one or more pieces of previously used metal catalyst gauze. Further, methods of making the metal catalyst materials comprise shaping the pieces of previously used metal catalyst gauze and placing them equidistant from each other in contact with or on the surface of the metal catalyst gauze. And methods of using the materials comprise feeding into the reactor a gas mixture of oxygen or air and one or more reactant gases, and igniting the gas mixture at the surface of one or more or all of the pieces of previously used metal catalyst.

A process for producing syngas that uses the syngas product from a partial oxidation reactor to provide all necessary heating duties, which eliminates the need for a fired heater. Soot is removed from the syngas using a dry filter to avoid a wet scrubber quenching the syngas stream and wasting the high-quality heat. Without the flue gas stream leaving a fired heater, all of the carbon dioxide produced by the reforming process is concentrated in the high-pressure syngas stream, allowing essentially complete carbon dioxide capture.