摘要:
A high-temperature tube furnace for pyrolysis includes a twin-hole ceramic tube including a pyrolysis capillary concentrically arranged within a sintering heat tube which is concentrically arranged within a thermally insulated tube housing. At least one heating tube holding element that is electrically insulative and high-temperature resistant is provided and includes at least three pins disposed radially about the sintering heating tube. Each pin is mounted to the tube housing via a clamp in such a way that the pins are adjustable in the radial direction so that the sintering heating tube is removably disposed between the tips of the pins. The sintering heating tube is connected to a voltage source for applying a heating current to thereto.
摘要:
A process is proposed for preparing isocyanates by thermally cleaving carbamates to obtain a carbamate cleavage gas comprising the corresponding isocyanate and the corresponding alcohol, which comprises quenching the carbamate cleavage gas in the presence of an ether which functions as an inhibitor for the reverse reaction of the isocyanate with the alcohol.
摘要:
The present invention relates to a process for the production of isocyanates, preferably diisocyanates and polyisocyanates of the diphenylmethane series (MDI), by reacting an amine with phosgene in the liquid phase or in the gas phase to form the corresponding isocyanates, subsequent removal of the solvent in at least two steps to obtain at least two solvent streams, individual treatment of the at least two solvent streams, and re-circulation of at least a portion of the solvent streams.
摘要:
The present invention relates to an implantable chamber (1) with a connecting element (2), comprising a connecting sleeve (6) and a surrounding contact surface (7), an insert element (3), comprising an insert sleeve (8) and a surrounding abutment surface (9). The insert sleeve (8) is inserted into the connecting sleeve (6) of the connecting element (2). The implantable chamber (1) further comprises a cap (4) with a surrounding edge (11), the cap (4) partly covering the connecting element (2) and the insert element (3), leaving an opening (13) on one side. The implantable chamber (1) contains a passive resonance circuit (14) with an inductance and a capacitance, the passive resonance circuit (14) surrounding at least part of a cavity (15) inside the insert element (3).
摘要:
A pipe anchor having: a base cradle with a lug; a top cradle with a lug and secured to the base cradle so as to encircle a pipe within the base cradle and the top cradle; a locking mechanism with opposite mating components attached to the base cradle and the top cradle; at least one lug attached to the pipe; and insulation material filling a space between the pipe and the cradles, wherein the insulation material engages the at least one lug of the pipe and the lugs of the cradles.
摘要:
A process is proposed for preparing isocyanates by thermally cleaving carbamates to obtain a carbamate cleavage gas comprising the corresponding isocyanate and the corresponding alcohol, which comprises quenching the carbamate cleavage gas in the presence of an ether which functions as an inhibitor for the reverse reaction of the isocyanate with the alcohol.
摘要:
The invention relates to a process for obtaining a dialkyl carbonate and an alkylene glycol from a stream comprising dialkyl carbonate, alkylene carbonate, alkylene glycol and alcohol, comprising the following steps: (a) distillatively removing a stream (5) comprising dialkyl carbonate and alkylene glycol as a heteroazeotrope from the stream comprising dialkyl carbonate, alkylene carbonate, alkylene glycol and alcohol in a first distillation stage (1), (b) separating the stream (5) comprising dialkyl carbonate and alkylene glycol as a heteroazeotrope into a first crude product stream (27) comprising essentially di-alkyl carbonate and a second crude product stream (29) comprising essentially alkylene glycol in an apparatus for phase separation (25).
摘要:
This invention relates to a process for working up residues from production of isocyanates. This process involves hydrolyzing residues from production of at least one isocyanate with water to form a hydrolysis product, and processing the hydrolysis product within an extruder or a kneader having a heat transfer surface, to form a mixed product containing at least one amine and water. The amine and the water are separated from the mixed product to form an amine/water mixture, which is then separated to obtain the water and the amine. The process may also involve separating all or part of the water from the hydrolysis, or separating part of the amine from the hydrolysis, prior to the processing of the hydrolysis product.
摘要:
The content of the invention is a process for preparing urethanes by reaction of aromatic amines with a dialkyl carbonate, wherein the alkyl radical of the organic dialkyl carbonate comprises 4-18 carbon atoms and is branched in the 2 position, and the reaction is performed in the presence of a substoichiometric amount of base, based on the amino groups.