405results about "Supercritical condition processes" patented technology

A method for large-scale manufacturing of gallium nitride boules. Large-area single crystal seed plates are suspended in a rack, placed in a large diameter autoclave or internally-heated high pressure apparatus along with ammonia and a mineralizer, and grown ammonothermally. The seed orientation and mounting geometry are chosen to provide efficient utilization of the seed plates and of the volume inside the autoclave or high pressure apparatus. The method is scalable up to very large volumes and is cost effective.

Submicron particles of water-insoluble compounds, particularly drugs, are prepared by simultaneously stabilizing microparticulate suspensions of same with surface modifier molecules by rapid expansion into an aqueous medium from a compressed solution of the compound and surface modifiers in a liquefied gas and optionally homogenizing the aqueous suspension thus formed with a high pressure homogenizer.

Coal is converted into hydrocarbon compounds using supercritical water. The process involves two stages; a first stage in which carbonaceous material is reacted with supercritical water at above 850K to produce a first supercritical fluid reaction mixture comprising hydrocarbon compounds; and a second stage in which hydrocarbon compounds are extracted from coal mixed with at least a portion of the first supercritical fluid at a temperature within a range of from the supercritical temperature of water to about 695K. Char from the second stage is finely divided and may be either be used outside the process, e.g. in a coal fired power station or a gasifier, or used as at least a portion of the carbonaceous material used in the first stage.

A reactor for conducting a process using supercritical water to upgrade a heavy hydrocarbon feedstock into an upgraded hydrocarbon product or syncrude with highly desirable properties (low sulfur content, low metals content, lower density (higher API), lower viscosity, lower residuum content, etc.) is described. The reactor is operable under continuous) semi-continuous or batch mode and is equipped with means to enable momentum, heat and mass transfer in and out of and within the reactor.

A method for large-scale manufacturing of gallium nitride includes a process for reducing and/or minimizing contamination in the crystals, for solvent addition to an autoclave, for improving or optimizing the solvent atmosphere composition, for removal of the solvent from the autoclave, and for recycling of the solvent. The method is scalable up to large volumes and is cost effective.

A gas-phase method for producing high yields of single-wall carbon nanotubes with high purity and homogeneity is disclosed. The method involves using preformed metal catalyst clusters to initiate and grow single-wall carbon nanotubes. In one embodiment, multi-metallic catalyst precursors are used to facilitate the metal catalyst cluster formation. The catalyst clusters are grown to the desired size before mixing with a carbon-containing feedstock at a temperature and pressure sufficient to initiate and form single-wall carbon nanotubes. The method also involves using small fullerenes and preformed sections of single-wall carbon nanotubes, either derivatized or underivatized, as seed molecules for expediting the growth and increasing the yield of single-wall carbon nanotubes. The multi-metallic catalyst precursors and the seed molecules may be introduced into the reactor by means of a supercritical fluid. In addition the seed molecules may be introduced into the reactor via an aerosol or smoke.

A capsule for containing at least one reactant and a supercritical fluid in a substantially air-free environment under high pressure, high temperature processing conditions. The capsule includes a closed end, at least one wall adjoining the closed end and extending from the closed end; and a sealed end adjoining the at least one wall opposite the closed end. The at least one wall, closed end, and sealed end define a chamber therein for containing the reactant and a solvent that becomes a supercritical fluid at high temperatures and high pressures. The capsule is formed from a deformable material and is fluid impermeable and chemically inert with respect to the reactant and the supercritical fluid under processing conditions, which are generally above 5 kbar and 550° C. and, preferably, at pressures between 5 kbar and 80 kbar and temperatures between 550° C. and about 1500° C. The invention also includes methods of filling the capsule with the solvent and sealing the capsule, as well as an apparatus for sealing the capsule.

Provided is a process for the supercritical upgrading of petroleum feedstock, wherein the process includes the use of a start-up agent, wherein the use of the start-up agent facilitates mixing of the petroleum feedstock and water, thereby reducing or eliminating the production of coke, coke precursor, and sludge.

A method for producing nano-carbon materials, having a step wherein a starting material comprising one or more kinds of compounds selected from the group consisting saturated hydrocarbons, unsaturated hydrocarbons, saturated cyclic hydrocarbons, and alcohols whose atomic ratio of the component carbon to the component oxygen is more than 2.0 and a catalyst are together treated at a temperature in a range of from 100 to 800° C. while being compressed at a pressure in a range of from 0.2 to 60 MPa, where said starting material is converted into a supercritical fluid or a subcritical fluid while said supercritical fluid or said subcritical fluid being contacted with said catalyst, or a step wherein said starting material, said catalyst and a supplementary material capable of functioning as a reaction promotion medium are together treated at a temperature in a range of from 100 to 800° C. while being compressed at a pressure in a range of from 0.2 to 60 MPa, where at least said supplementary material is converted into a supercritical fluid or a subcritical fluid and said starting material is contacted with said supercritical fluid or said subcritical fluid formed from said supplementary material while being contacted with said catalyst.

A process and system for upgrading an organic feedstock including providing an organic feedstock and water mixture, feeding the mixture into a high-rate, hydrothermal reactor, wherein the mixture is rapidly heated, subjected to heat, pressure, and turbulent flow, maintaining the heat and pressure of the mixture for a residence time of less than three minutes to cause the organic components of the mixture to undergo conversion reactions resulting in increased yields of distillate fuels, higher-quality kerosene and diesel fuels, and the formation of high octane naphtha compounds. Hydrocarbon products are cooled at a rate sufficient to inhibit additional reaction and recover of process heat, and depressurizing the hydrocarbon products, and separating the hydrocarbon products for further processing. The process and system can include devices to convert olefinic hydrocarbons into paraffinic hydrocarbons and convert olefinic byproduct gas to additional high-octane naphtha and/or heavier hydrocarbons by one of hydrogenation, alkylation, or oligomerization.