Abstract:
Method for the production of urea from ammonia and carbon dioxide in a urea plant containing a high-pressure synthesis section with a horizontal pool condenser, wherein the method comprises exchanging heat from a high pressure process medium received in a shell section of the pool condenser to a medium pressure urea containing solution received in a first heat exchanging section provided in the pool condenser to at least decompose ammonium carbamate into NH 3 and CO 2 , wherein the method further comprises exchanging heat from the high pressure process medium to a low pressure steam condensate received in a second heat exchanging section provided in the pool condenser to produce low pressure steam. The invention also relates to an apparatus for the production of urea from ammonia and carbon dioxide.
Abstract:
Disclosed is a reactor system for the production of polyester pre-condensate. The system comprises at least two reaction zones, operating at substantially different pressure. Reactants fed into the first zone are allowed to initially react and are then allowed to enter a second zone by means of pressure flow. In the second zone, a system of concentric spacers is present so as to ensure a sufficient path length of the reaction mixture to form a pre-condensate, as well as in internal heat exchanger. The pre-condensate is allowed to flow to a next (polymerization) stage by means of gravity flow on account of a standpipe present in the second reaction zone. Said standpipe has an inlet above the internal heating system in the second reaction zone.
Abstract:
Disclosed is a process for the concurrent production of hydrogen and sulphur from a H 2 S-containing gas stream, with reduced, and preferably zero, emissions. The method comprises the catalytic oxidative cracking of H 2 S so as to form H 2 and S 2 . Preferably, the oxidation is conducted using oxygen-enriched air, preferably pure oxygen. The process is conducted in a reaction chamber comprising a bifunctional catalyst material, so as to favor both the partial oxidation of H 2 S and the dissociation thereof.
Abstract:
The invention relates to the production of hydrogen by steam reforming comprising the steps of (i) providing a fossil fuel, preferably methane, and steam, (ii) conducting a steam reforming reaction between the fossil fuel and the steam under heating, wherein a reaction mixture is formed comprising hydrogen and carbon dioxide, (iii) separating hydrogen from the reaction mixture by membrane separation, wherein a permeate is formed comprising hydrogen and a retentate comprising carbon dioxide, (iv) purifying carbon dioxide from the retentate, and (v) using said carbon dioxide as a heat exchange medium to supply heat at least for the steam reforming reaction (ii). The method of the invention can also be used for the production of pressurised carbon dioxide characterised by a high purity. Further, the invention relates to a system for hydrogen production and to the use of pressurised carbon dioxide as heat exchange medium.
Abstract:
The invention is related to a liquid composition comprising (1) a silicon oligomer comprising a group derivable from an alkoxylated silicone, at least two groups chosen from the group consisting of urethane and urea groups obtained from a polyisocyanate and at least one ethylenical unsaturation and (2) at least one polyfunctional cross-linking agent. The liquid composition is suitable in producing ribbon coatings for optical glass fibers.
Abstract:
Process for the polymerization of cyclic esters, using a metal salt as a catalyst, whereby the catalyst consists of a compound with formula (I) where M is a metal ion and n a number from 1 to 4 and being smaller or equaling the valency of the metal ion and where the R and R groups are, independently of each other, alkyl, aryl or cycloaliphatic groups and R is an alkyl, aryl, cycloaliphatic group or a hydrogen atom and where the R -R groups are so chosen that the catalyst has a melting point lower than the desired polymerization temperature. Polymers produced while applying a process or a catalyst according to the invention can be used in numerous fields, but are of particular advantage in biomedical applications as bio-resorbable material, as described in literature.
Abstract:
This invention relates to a radiation-curable monoethylenically unsaturated liquid non-aqueous composition whereby the composition comprises an ionomeric composition comprising a monoethylenically unsaturated acid wherein at least a portion of the acid groups thereof is neutralized by a metal ion-producing component. An investment casting method utilizing a pattern produced from the composition is also disclosed.
Abstract:
Oligomeric acrylates containing composition suitable for the production of endless objects without the use of continuous carrier material, whereby the composition also contains a high molecular weight thermoplastic polymer. Products made from a composition according to the invention are, depending on the starting materials, suitable for applications in those areas where a good temperature resistance, a good fire resistance and/or a good corrosion and solvent resistance are required besides good mechanical properties. Examples are cable sheathing, fireproof clothing, asbestos replacement, high temperature filters, aircraft interiors, precursors for carbon fibre, food packagings (for instance for use in a microwave oven), condenser films, optical fibre and filament winding products.
Abstract:
Elongated object, made of an orientated alternating copolymer of carbon monoxide and an olefinically unsaturated monomer, which has a modulus of elasticity of at least 16 GPa, and a method for the production of objects from an alternating copolymer, orientated by stretching, of carbon monoxide and an olefinically unsaturated monomer, by dissolving the copolymer in a suitable solvent, converting the solution obtained, at a temperature above the dissolving point of the solution, to an object consisting of the solution, converting the object consisting of the solution to a solvent-containing object consisting of the copolymer, completely or partially removing the solvent from the solvent-containing object consisting of the copolymer and stretching at least the object thus obtained, or the solvent-containing object consisting of the copolymer, at elevated temperature, it being possible for the stretching of tapes and films also to take place in two directions.
Abstract:
The invention relates to a thermoplastic polymer based on a vinyl monomer, which is characterized in that the polymer composition contains more than 1% (wt) of one or more compounds according to formula (I) and/or (II), where R is a hydrogen atom, alkyl, aryl, cycloalkyl, cycloaryl and/or a halogen. By applying a polymer according to the invention the composition is protected against thermal decomposition so that the CO2 emission during or after processing is lower than 0.5% (wt). Polymers according to the invention are excellently suited for the production therefrom of dashboards for motor cars and of housings for electric equipment.