Hoechst Aktiengesellschaft

Bernhard Kuxdorf

Karl Kaiser

Herbert Pusche

Ursus Thummler

Hugo Werner

Kurt Wissel

Peter Luhr

Heinz Erpenbach

Harald Scholz

Friedrich-Wilhelm Dorn

Hans Hennen

Robert Queck

Wernfried Riechmann

Joachim Hundeck

Robert Willms

Rudolf Wesselmann

Walter Klemm

Hellmuth Daniel

The disclosure relates to a process for making 1,2-dichloroethane by reacting ethylene and chlorine in a reaction zone having a liquid medium containing chlorinated C.sub.2 -hydrocarbons circulated therein. To this end, the disclosure provides:

Process for making 1,2-dichloroethane

The disclosure relates to a process for making phosphorus pentoxide by subjecting elemental yellow phosphorus to combustion with dried air inside a steel-made combustion chamber with utilization of the reaction heat for the production of energy. To this end, the disclosure provides for the combustion to be effected inside a combustion chamber of which the walls are arranged so as to form a cooling system with cavities therein; for water or a water/steam-mixture as a heat carrier abstracting the reaction heat to be circulated through the cooling system, the water or water/steam-mixture assuming an increased temperature being circulated, preferably under increased pressure; for steam formed in the cooling system to be continuously taken therefrom; for an equivalent proportion of fresh desalted water to be introduced into the cooling system; for hot gaseous phosphorus pentoxide issuing from the combustion chamber to be condensed or worked up into phosphoric acid; for the steam taken from the cooling system to be passed through a steam delivery pipe disposed in the upper portion of the combustion chamber, or through a delivery conduit for product gas containing phosphorus pentoxide; for the steam to be heated therein to a temperature of 400.degree. to 600.degree. C. under constant pressure, and for the steam so superheated to be used.

Process for making phosphorus pentoxide and optionally phosphoric acid

The disclosure relates to a process for making phosphorus pentoxide by subjecting elemental yellow phosphorus to combustion with dried air inside a steel-made combustion chamber with utilization of the reaction heat for the production of energy. To this end, the disclosure provides for the combustion to be effected inside a combustion chamber of which the walls are arranged so as to form a cooling system with cavities therein; for a liquid or liquid/steam-mixture as a heat carrier abstracting the reaction heat to be circulated through the cooling system, the liquid or liquid/steam-mixture assuming an increased temperature being preferably so circulated under increased pressure; for steam formed in the cooling system to be continuously taken therefrom; for an equivalent proportion of fresh liquid to be introduced into the cooling system; for hot P.sub.2 O.sub.5 issuing in vapor form from the combustion chamber to be condensed or worked up into desirable final product, the combustion chamber being a cylindrical vessel with a height/diameter-ratio of 2.5:1 to 5:1 and having 1 to 10 burners disposed axisymmetrically in its circular base plate. The disclosure also relates to an apparatus for carrying out the process.

Process and apparatus for making phosphorus pentoxide with utilization

The invention relates to process for making phosphorus pentoxide by subjecting elementary phosphorus to a combustion reaction with the aid of air, the reaction heat being utilized for the production of energy. To this end, the invention provides for the phosphorus to be subjected to combustion with dry air containing, per m.sup.3, 5 g down to 0.01 g of water, inside a combustion chamber of which the metallic walls are arranged so as to form a cooling system with cavities therein and for a liquid and liquid/steam-mixture, respectively, to be circulated through the cooling system under pressure within the range 1 to 150 bars, the liquid or mixture assuming a temperature of more than 150.degree. C. up to 500.degree. C. Steam which is formed in the cooling system is continuously taken therefrom and replaced by an equivalent proportion of fresh liquid.

Production of phosphorus pentoxide with utilization of reaction heat

A degassing column comprising a tubular shell provided with a plurality of apertured plates; the plates are vertically spaced within said shell; a gap uniform in width over the periphery is left between each plate and said shell; each of said plates is penetrated by at least one eccentrically arranged conduit comprising a draining shaft in the upper portion thereof and a feed shaft in the lower portion below the penetrated plate; the apertures in said plates have a diameter of less than 5 mm; and a surface portion of each plate underneath each conduit is impermeable, said impermeable surface portion being one to two times the cross-section of said conduit. More specifically, each plate is supported by a plurality of generally wedge-shaped mountings fastened to the inside of the shell, and by a ring which is level with the said mountings and is fastened to the inside of the shell, the ring being interrupted at least in the regions of the said mountings. A capping sleeve is slipped over each draining shaft. The capping sleeve comprises an upper portion whose cross-section is similar to that of the draining shaft, and a lower portion of larger cross-section, which lower portion overlaps and is securely connected to the upper portion.

Degassing column

The invention relates to an improved process, wherein polyolefins are freed from saturated liquid residual hydrocarbons with the aid of water and steam. The improvement comprises

Process and apparatus for the continuous removal of residual

An aqueous polymer dispersion containing approximately 1 to 60 weight % of solid polymer particles with an average size of 20 to 500 microns and 5000 to 15,000 ppm of monomer(s), is freed from monomeric material. More specifically, the aqueous dispersion is preheated to 60.degree. to 90.degree. C. and introduced continuously into an upper portion of a column accommodating a plurality of apertured trays disposed one above another of which each has at least one eccentric aqueous dispersion descent shaft. The aqueous dispersion is introduced at a rate of a 5 to 35 m.sup.3 per m.sup.2 of tray area per hour and contacted countercurrently with steam at 80.degree. to 150.degree. C., under 0.5 to 5 bars, and in a proportion of 30 to 100 kg of steam per m.sup.3 of dispersion, for a mean period of 1 to 30 minutes; the pressure drop for steam ascending through one tray in the column being lower than that which would occur upon the undesirable passage of steam through one of the said shafts. At the column base, aqueous dispersion freed from monomeric material is removed and a vapor mixture emerging at an upper level of the column, is condensed, and monomeric material and an aqueous phase are recovered therefrom.

Continuous removal of monomers from an aqueous dispersion of a polymer

In a degassing column with several perforated plates arranged over one another and at a distance from one another in a column housing there is left free, between each plate and the column housing, a gap which is as small as possible and is uniform over the periphery, and the apertures in the plates have a diameter of less than 5 mm. Each plate is penetrated by at least one eccentrically arranged draining shaft, and at least one eccentrically arranged feed shaft ends above each plate. Finally, below each feed shaft on the plate an area is impermeable which is at least as large as the cross-section of the feed shaft.

A distillation column comprising a shell which has serially arranged therein a plurality of distilling trays with respective liquid inlets and outlets. An annular slit of substantially uniform width is left between the individual trays and the shell. The slit may be interrupted by a plurality of spacers which bear against the inner surface of the shell, and the spacers are provided around the periphery of the individual trays.

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Bruhl, Germany

Bernhard Kuxdorf