Abstract: The present invention relates to a process for extracting aromatic dicarboxylic acids from an outlet stream of a basic depolymerization of polycondensates containing metal carboxylates of the aromatic dicarboxylic acid to be extracted, wherein a mineral or organic acid is added to this outlet stream, the pKs value of which acid being greater than or equal to that of the aromatic dicarboxylic acid, on which the polycondensate is based.

Abstract: The invention relates to a method for producing a mixture of recycled terephthalic acid (r-TA) and recycled iso-terephthalic acid (r-IA) from condensation polymer waste (CP waste) to obtain a mixture of r-TA and r-IA having set r-IA isomer content between 0.001% by weight and 25% by weight of the mixture, for which waste having different IA contents is mixed and processed.

Abstract: A method and a device for reprocessing waste products containing substantially polyalkylene terephthalate, particularly polyethylene terephthalate and/or polybutylene terephthalate, in a continuous process by means of depolymerizing is provided. A solid alkali hydroxide and/or alkali earth hydroxide, particularly sodium hydroxide, is added to the waste products for producing a reaction mixture, suitable for recycling multilayer systems and colored material nearly entirely chemically into the starting materials at a high throughput and high quality, in order to be able to produce new polyalkylene terephthalate products from the recycling products without limitation. An alkylene glycol is additionally added to the reaction mixture as a reactant, wherein the alkylene glycol is an alkylene glycol produced as a product of the intended depolymerizing, particularly MEG. No further reactive components are added to the reaction mixture.

Abstract: A turbine rotor, e.g., for a drive turbine of a rotary atomizer, is disclosed having a rotatably supported turbine shaft with the potential for mounting an atomizer wheel, and having at least one drive turbine wheel having a plurality of turbine blades. The turbine blades of the drive turbine wheel may be impinged on during operation by a drive fluid in order to drive the turbine rotor. The drive turbine wheel may be designed for the drive fluid to axially impinge on the turbine blades. A complete drive turbine having such a turbine rotor is also disclosed, as well as a complete rotary atomizer and individual exemplary components of the drive turbine.

Abstract: A rotary atomizer is disclosed, comprising an atomizer bell and a shaft carrying the same. The rotary atomizer may further include a retainer between the atomizer bell and the shaft, said retainer preventing, e.g., by the action of a centrifugal force, the atomizer bell from detaching itself from the shaft.

Abstract: A turbine rotor, e.g., for a drive turbine of a rotary atomizer, is disclosed having a rotatably supported turbine shaft with the potential for mounting an atomizer wheel, and having at least one drive turbine wheel having a plurality of turbine blades. The turbine blades of the drive turbine wheel may be impinged on during operation by a drive fluid in order to drive the turbine rotor. The drive turbine wheel may be designed for the drive fluid to axially impinge on the turbine blades. A complete drive turbine having such a turbine rotor is also disclosed, as well as a complete rotary atomizer and individual exemplary components of the drive turbine.

Abstract: A rotary atomizer is disclosed, comprising an atomizer bell and a shaft carrying the same. The rotary atomizer may further include a retainer between the atomizer bell and the shaft, said retainer preventing, e.g., by the action of a centrifugal force, the atomizer bell from detaching itself from the shaft.

Abstract: Isocyanates are prepared by reacting primary amines with phosgene in a reactor by a process in which a reaction discharge is present in the form of a suspension which contains the isocyanate to be prepared, as a liquid, and carbamyl chlorides as a solid, and the suspension is worked up in a film evaporator, and this process is carried out in a production plant.

Abstract: Isocyanates are prepared by reacting primary amines with phosgene in a reactor by a process in which a reaction discharge is present in the form of a suspension which contains the isocyanate to be prepared, as a liquid, and carbamyl chlorides as a solid, and the suspension is worked up in a film evaporator, and this process is carried out in a production plant.

Abstract: A process for working up residues from the preparation of pyrrolidone and/or N-vinylpyrrolidone comprises subjecting the residues to a thermolysis.

Abstract: A method of reacting a solution comprising a mixture of chemical compounds which are in chemical equilibrium with one another with at least one further chemical compound (9) is provided. The method comprises the following steps: fractionation of the solution by means of a separation method to give at least two fractions (5, 6) which are enriched in different chemical compounds of the mixture; and reaction of a fraction (5) with the further chemical compound or compounds (9). The fractionation is advantageously carried out using a film evaporator (1). Unreacted fractions (6) can be recirculated via a residence time vessel (3) back to the fractionation step. The method is particularly suitable for reactions of an aqueous formaldehyde solution in which various components of the solution (formaldehyde, methylene glycol, polyoxymethylene glycols) react in different ways.

Abstract: A process for working up residues from the preparation of pyrrolidone and/or N-vinylpyrrolidone comprises subjecting the residues to a thermolysis.

Abstract: The invention relates to a process for the production of a heat transfer device, which comprises electroless chemical deposition of a metal/polymer dispersion layer, in which the polymer is halogenated, on a heat transfer surface. The invention furthermore relates to a process for the production of a heat transfer device, wherein a metal/phosphorus layer with a thickness of from 1 to 15 &mgr;m is applied by electroless chemical deposition before application of the metal/polymer dispersion layer. The invention furthermore relates to a heat transfer device which can be produced by a process according to the invention, and to the use of a coating, produced by electroless chemical deposition of a metal/polymer dispersion layer, in which the polymer is halogenated, for reducing the tendency of the coated surfaces to accumulate solids from fluids, causing fouling.

Abstract: A process for distilling ethylene oxide out of a mixture including ethylene oxide in a column at an absolute pressure of from 2 to 10 bar and a temperature of 20 to 180.degree. C. by withdrawing pure ethylene oxide in the liquid or gaseous state overhead or via a sidestream in the rectifying section of the column includes effecting the distillation in a column having on its inside a plurality of successive zones of structured sheet-metal packing or dumped beds of packing elements, these zones being assigned one or more extinguishing systems on the outside of the column.

Abstract: The invention relates to a process for evaporating a liquid containing vaporizable oxidation-sensitive compounds in an evaporator in which the liquid is brought into contact with a heated solid surface for evaporation, by a process in which direct contact between the resulting vapor phase and the heated solid surface is substantially avoided. It also directed to an evaporator composed of a heatable solid surface (16), an apparatus (2, 3) for heating the solid surface and an apparatus (10) for feeding a liquid containing vaporizable compounds to the heatable solid surface, wherein the apparatus for feeding the liquid is designed and arranged in the evaporator in such a way (12, 14, 18) that direct contact between a resulting vapor phase and the heatable solid surface is substantially avoided.

Abstract: Neopentyl glycol hydroxypivalate (NGH) is isolated from a mixture containing NGH, lower- and higher-boiling products and inorganic salts and purified in a two-stage process, whereinin a first separation stage, the inorganic salts and part of the higher-boiling products are separated off in a wiped-film evaporator and a vapor stream consisting of NGH, lower- and higher-boiling products is discharged and fed to a heat exchanger and condensed therein,and, in a second separation stage, the resulting condensate is distilled in a rectification column from which NGH is taken off in a side stream and condensed. Further discharges of the rectification column containing lower-boiling products or higher-boiling products are separately taken off. The higher-boiling products which comprise residual NGH are partly or completely recycled to the lower region of the rectification column.