Abstract:
Autoclaves with combined airflow to provide controllable heating or cooling of parts being processed are disclosed. Gas flow along the autoclave is provided in one or more duct areas (48,52), with a plurality of duct valves (50) along the duct (48,52) controllably diverting the gas into the working area of the autoclave. In a fully configured autoclave, duct valves (50) divert gas flowing from the fan or blower (38) from the ceiling, sides and floor of an autoclave to provide a controllable, three dimensional, air flow in the working area of the autoclave. Control of the duct valves (50) may be manual or automatic, with individual or ganged duct valve control. Computer control based on temperature sensor on parts in the working area of the autoclave may be used to provide uniform heating or cooling, or intentional non-uniform heating or cooling rates. Various embodiments are disclosed.
Abstract:
A process of making a crystalline powder and the powder. The process includes providing at least a precursor material; hydrothermal synthesis to create a predetermined amount of boehmite as an intermediate product from the at least precursor material; hydrothermal synthesis to convert at least a portion of the boehmite to alpha alumina, wherein any remaining, un-converted boehmite is attached to alpha alumina. The process may be part of a process to make and extrudate and the extrudate. The composition and extrudate may include alpha alumina crystals with surface adhesions of boehmite. An apparatus for hydrothermal synthesis of high purity alpha alumina powder, the apparatus including an autoclave with titanium liners, a pressure relief system and a heat exchanger.
Abstract:
The present invention discloses the process of supplying high pressure (e.g., 30 atmospheres) CO that has been preheated (e.g., to about 1000° C.) and a catalyst precursor gas (e.g., Fe(CO)5) in CO that is kept below the catalyst precursor decomposition temperature to a mixing zone. In this mixing zone, the catalyst precursor is rapidly heated to a temperature that results in (1) precursor decomposition, (2) formation of active catalyst metal atom clusters of the appropriate size, and (3) favorable growth of SWNTs on the catalyst clusters. Preferably a catalyst cluster nucleation agency is employed to enable rapid reaction of the catalyst precursor gas to form many small, active catalyst particles instead of a few large, inactive ones. Such nucleation agencies can include auxiliary metal precursors that cluster more rapidly than the primary catalyst, or through provision of additional energy inputs (e.g., from a pulsed or CW laser) directed precisely at the region where cluster formation is desired. Under these conditions SWNTs nucleate and grow according to the Boudouard reaction. The SWNTs thus formed may be recovered directly or passed through a growth and annealing zone maintained at an elevated temperature (e.g., 1000° C.) in which tubes may continue to grow and coalesce into ropes.
Abstract:
In a process for preparing polyethylene in tube reactors with or without autoclaves, where a free-radical initiator is introduced with or without cold ethylene into a flowing ethylene- and comonomer-containing medium, rotation is generated between two streams (61, 62) to be mixed at an angle (66) or by provision of a swirl element (20, 80) in the flow cross section (27, 28). In the region of a feed point (72, 81) for a free-radical initiator, there is provided a cross-sectional constriction (63, 67, 71) at which the free-radical initiator is introduced through an optimized off-center outlet opening (44) of an introduction finger (40) into the rotating flow (61, 62, 70).
Abstract:
A method for oxidizing organic matter contained in an aqueous effluent and an installation for implementing the method. The method comprises the following steps: injecting into a tubular body the aqueous effluent; bringing the aqueous effluent to a pressure P1, corresponding to the critical pressure of the aqueous effluent; bringing the aqueous effluent to a temperature T1; and injecting into the tubular body at n points spaced apart from one another, n fractions of at least an oxidizing composition, so that a portion of the thermal energy produced by the oxidation reaction increases the temperature of the reaction mixture from said temperature T1 to temperature T2>T1 according to an increasing curve, whereby the organic matter is oxidized, the reaction mixture continuously developing from a sub-critical liquid state to the supercritical domain.
Abstract:
The present invention discloses the process of supplying high pressure (e.g., 30 atmospheres) CO that has been preheated (e.g., to about 1000null C.) and a catalyst precursor gas (e.g., Fe(CO)5) in CO that is kept below the catalyst precursor decomposition temperature to a mixing zone. In this mixing zone, the catalyst precursor is rapidly heated to a temperature that results in (1) precursor decomposition, (2) formation of active catalyst metal atom clusters of the appropriate size, and (3) favorable growth of SWNTs on the catalyst clusters. Preferably a catalyst cluster nucleation agency is employed to enable rapid reaction of the catalyst precursor gas to form many small, active catalyst particles instead of a few large, inactive ones. Such nucleation agencies can include auxiliary metal precursors that cluster more rapidly than the primary catalyst, or through provision of additional energy inputs (e.g., from a pulsed or CW laser) directed precisely at the region where cluster formation is desired. Under these conditions SWNTs nucleate and grow according to the Boudouard reaction. The SWNTs thus formed may be recovered directly or passed through a growth and annealing zone maintained at an elevated temperature (e.g., 1000null C.) in which tubes may continue to grow and coalesce into ropes.
Abstract:
The present invention discloses the process of supplying high pressure (e.g., 30 atmospheres) CO that has been preheated (e.g., to about 1000° C.) and a catalyst precursor gas (e.g., Fe(CO)5) in CO that is kept below the catalyst precursor decomposition temperature to a mixing zone. In this mixing zone, the catalyst precursor is rapidly heated to a temperature that results in (1) precursor decomposition, (2) formation of active catalyst metal atom clusters of the appropriate size, and (3) favorable growth of SWNTs on the catalyst clusters. Preferably a catalyst cluster nucleation agency is employed to enable rapid reaction of the catalyst precursor gas to form many small, active catalyst particles instead of a few large, inactive ones. Such nucleation agencies can include auxiliary metal precursors that cluster more rapidly than the primary catalyst, or through provision of additional energy inputs (e.g., from a pulsed or CW laser) directed precisely at the region where cluster formation is desired. Under these conditions SWNTs nucleate and grow according to the Boudouard reaction. The SWNTs thus formed may be recovered directly or passed through a growth and annealing zone maintained at an elevated temperature (e.g., 1000° C.) in which tubes may continue to grow and coalesce into ropes.
Abstract:
A method and apparatus for processing substances by coexisting an object matter with water held at temperature above 200° C. to carry out chemical reactions such as severing of molecular chains, recombination and decoupling occluded molecules, oxidation and reduction reactions. A mixture phase containing an object matter and a liquid medium is subjected to a super-critical state of a medium in a super-critical reaction apparatus, where feed inlets are provided on the upper end, and a product outlet is provided on the lower end. In the interior of the apparatus, the super-critical zone is provided above and the sub-critical zone is provided below, and the object matter and the reaction products are progressed towards a lower end of a reaction chamber in one direction.
Abstract:
Process for the preparation of ethylene copolymers, and their use as additives to mineral oil and mineral oil distillates. The invention relates to a process for the preparation of terpolymers of ethylene and at least 2 further olefinically unsaturated compounds by polymerization in a tubular reactor fitted with at least one side branch, wherein the fresh monomer components, which are introduced into the tubular reactor via the reactor inlet (the primary stream) or via the side branch or side branches (secondary stream or secondary streams), in each of the streams contain ethylene and at most one further olefinically unsaturated compound.
Abstract:
A process for producing hollow, single-walled carbon nanotubes by catalytic decomposition of one or more gaseous carbon compounds by first forming a gas phase mixture carbon feed stock gas comprising one or more gaseous carbon compounds, each having one to six carbon atoms and only H, O, N, S or Cl as hetero atoms, optionally admixed with hydrogen, and a gas phase metal containing compound which is unstable under reaction conditions for said decomposition, and which forms a metal containing catalyst which acts as a decomposition catalyst under reaction conditions; and then conducting said decomposition reaction under decomposition reaction conditions, thereby producing said nanotubes.