Systems and methods for molten media pyrolysis for the conversion of methane into hydrogen and carbon-containing particles are disclosed. The systems and methods include the introduction of seed particles into the molten media to facilitate the growth of larger, more manageable carbon-containing particles. Additionally or alternatively, the systems and methods can include increasing the residence time of carbon-containing particles within the molten media to facilitate the growth of larger carbon-containing particles.

A method of preheating a feed to a molten material reactor comprises heating a hydrocarbon feed in a first heat exchanger using a cooled product gas to produce a heated hydrocarbon feed stream, pyrolyzing at least a portion of the C.sub.2+ hydrocarbons in the heated feed stream in a pyrolysis reactor to produce a pyrolyzed hydrocarbon stream, and heating the pyrolyzed hydrocarbon stream in a second heat exchanger using a product gas to produce a pre-heated feed gas. The heated hydrocarbon feed stream comprises methane and one or more C.sub.2+ hydrocarbons.

Reactor for the high-pressure non-catalytic synthesis of melamine from urea, comprising coaxial inner reaction zone (6) and outer reaction zone (7) wherein a crude melamine is formed in the inner reaction zone and contacted with gaseous ammonia for stripping in the outer reaction zone, wherein a gaseous phase liberated in the outer zone is collected in a gas collection chamber (12) above the reaction zones, wherein the crude melamine melt is transferred from the inner zone into the outer zone via a submerged liquid passage below the liquid level to provide a liquid seal between the chambers.

A method for thermal cracking of a hydrocarbon to produce hydrogen gas and carbon comprises heating a molten medium to an operating temperature sufficient to thermally crack the hydrocarbon. The operating temperature may, for example be in the range of 600° C. to 1100° C. The method mixes the hydrocarbon into the heated molten medium and pumping the mixed molten medium and hydrocarbon through a reactor. In the reactor, the hydrocarbon undergoes a thermal cracking reaction which forms hydrogen gas and carbon black. The method separates the carbon and hydrogen gas from the molten medium that has passed through the reactor. In some embodiments, the flow of the molten medium in the reactor is a turbulent flow.

The presently disclosed subject matter is generally directed to a system and method of reducing, reacting, and/or removing an oxidant or unwanted chemical species from a chemical stream. Particularly, the system and method include the use of one or more reductants that react with the undesired chemical species. The reductant and the chemical stream are added to a reactor and allowed to react for a desired amount of time. The reductant will reduce, react with, and/or remove the chemical species from the stream. The excess reductant and reaction products are then removed from the reactor, as described in more detail herein below.

A pyrolysis process comprises introducing one or more chemical reactants into a reactor containing a liquid maintained at a high temperature, producing chemical products in the liquid based on the high temperature, allowing the solid product to grow in particle size, accumulating the solid product in the liquid, and removing the solid product from the reactor while retaining a substantial portion of the liquid within the reactor. The chemical products comprise a solid chemical product that is mixed with the liquid.

The invention is directed to a system and method of reducing, reacting, and/or removing an oxidant or unwanted chemical species from a chemical stream. Particularly, the system and method include the use of one or more reductants that react with the undesired chemical species. The reductant and the chemical stream are added to a reactor and allowed to react for a desired amount of time. The reductant will reduce, react with, and/or remove the chemical species from the stream. The excess reductant and reaction products are then removed from the reactor, as described in more detail herein below.

A hydrogen production apparatus includes: a first furnace configured to heat a mixed gas of a raw material gas, which contains at least methane, and hydrogen to 1,000° C. or more and 2,000° C. or less; and a second furnace configured to accommodate a catalyst for accelerating a reaction of a first gas generated in the first furnace to a nanocarbon material, and to maintain the first gas at 500° C. or more and 1,200° C. or less.

A system and method are presented for producing metallic core-shell particles. The system includes the housing having a hollow interior configured to receive and hold a molten metal input, a carrier fluid, and one or more reagents. The system also includes a shearing assembly positioned within the hollow interior of the housing. The shearing assembly is configured to, when the molten metal input, carrier fluid, and one or more reagents are held withing hollow interior and sealed within housing, shear the molten metal input into particles of an effective size so that a shell created on a surface of the particles via reaction with the one or more reagents prevents a core of the particles from solidifying when the particles are cooled to a temperature below a freezing temperature of the molten metal input.

Described herein are processes and apparatus for the large-scale synthesis of boron nitride nanotubes (BNNTs) by induction-coupled plasma (ICP). A boron-containing feedstock may be heated by ICP in the presence of nitrogen gas at an elevated pressure, to form vaporized boron. The vaporized boron may be cooled to form boron droplets, such as nanodroplets. Cooling may take place using a condenser, for example. BNNTs may then form downstream and can be harvested.