Bayer Materialscience Ag

Covestro Deutschland Ag

Bayer Intellectual Property Gmbh

Solarworld Aktiengesellschaft

Knud Werner

Alfred Soppe

Ole Brettschneider

Friedhelm Steffens

Thomas Runowski

Torsten Erwe

Thorsten Leidig

Juergen Bittner

Hans-Dieter Block

Rainer Weber

Leslaw Mleczko

Gebhard Wagner

Jürgen Kintrup

Peter Lehner

Johannes-Peter Schäfer

Hans-Joachim Leimkühler

Karsten-Ulrich Klatt

Jun Wang

Dirk Weiβenberg

Eric Jakobs

Annette Conrad

Carsten Welz

Dietmar Schwanke

Jürgen Bittner

Dirk Weissenberg

The present invention relates to a process for purifying raw-material gases by fractionation. In particular, the present invention relates to a process for cleansing chlorine gas of bromine.

Process for purifying raw-material gases by fractionation

The invention relates to a process for the preparation of isocyanates in a system network comprising an isocyanate production plant, a chlorine production plant and a phosgene production plant, in which carbon dioxide formed as a by-product is partially to completely condensed out with the gaseous chlorine formed in the chlorine production plant and enters into the phosgene preparation process and, after the preparation of phosgene, the predominant part of the carbon dioxide formed is thereby sluiced out of the system network in gaseous form.

Process for the preparation of isocyanates

Processes comprising: providing an anion exchanger at least partially loaded with hexachlorostannate; and contacting the at least partially loaded anion exchanger with a 1 to 10 wt. % hydrochloric acid solution to regenerate the anion exchanger.

Processes for the regeneration of an anion exchanger loaded with hexachlorostannate

A process is described for the production of chlorine by a catalysed gas-phase oxidation of hydrogen chloride with an oxygen-containing gas stream.

Process for producing chlorine from HCL

Processes comprising: providing a crude gas stream having a temperature not exceeding 40&#xb0; C., the crude gas stream comprising hydrogen chloride and at least one organic impurity; condensing at least a portion of the at least one organic impurity from the crude gas stream at a temperature not exceeding 0&#xb0; C. to form a prepurified gas stream and a condensate comprising condensed organic impurity; subjecting at least a portion of the prepurified gas stream to adsorption on an adsorption medium to provide a purified gas stream; and separating the condensate into at least a head gas stream comprising residual hydrogen chloride and a sump stream comprising at least a portion of the condensed organic impurity.

Processes for removing organic components from gases containing hydrogen chloride

Process for providing a purified gas stream, comprising: providing a crude gas stream comprising an organic impurity; condensing at least a portion of the impurity from the gas stream to form a prepurified gas stream; and subjecting the prepurified stream to adsorption on a first adsorption medium; wherein the first medium is subjected to a regeneration comprising: providing a circulating inert gas stream having a temperature of at least 100&#xb0; C.; passing the circulating inert gas stream over the first medium to form an organic impurity-loaded inert gas stream; cooling the loaded stream; condensing at least a portion of the organic impurity from the cooled stream to provide a prepurified circulating inert gas stream; subjecting the prepurified gas stream to adsorption on a second adsorption medium to provide a purified circulating inert gas stream; and recycling the purified gas stream to the circulating inert gas stream.

Regenerative adsorption processes for removing organic components from gas streams

The invention relates to a method for the production of high purity silicon, characterized by the following steps: a) reaction of metallic silicon with silicon tetrachloride (SiCl), hydrogen (H) and hydrochloric acid (HCl) at a temperature of 500 to 800&#xb0; C. and a pressure of 25 to 40 bar to give a trichlorosilane-containing (SiHCl) feed gas stream, b) removal of impurities from the resultant trichlorosilane-containing feed gas stream by scrubbing with condensed chlorosilanes at a pressure of 25 to 40 bar and a temperature of 160 to 200&#xb0; C. in a multi-stage distillation column, to give a purified trichlorosilane-containing feed gas stream and a solid-containing chlorosilane suspension and a distillative separation of the purified feed gas stream into a partial stream essentially comprising SiCland a partial stream, essentially comprising SiHCl, c) disproportionation of the SiHCl-containing partial stream to give SiCland SiH, whereby the disproportionation is carried out in several reactive/distillative reaction zones, with a counter-current of vapour and liquid, on catalytic solids at a pressure of 500 mbar to 50 bar and SiHClis introduced into a first reaction zone, the lower boiling SiH-containing disproportionation product produced there undergoes an intermediate condensation in a temperature range of &#x2212;25&#xb0; C. to 50&#xb0; C., the non-condensing SiH-containing product mixture is fed to one or more further reactive/distillative reaction zones and the lower boiling product thus generated, containing a high proportion of SiHis completely or partially condensed in the head condenser and d) thermal decomposition of the SiHto give high purity silicon.

Method for production of high purity silicon

Growing community of inventors

Krefeld, Germany

Knud Werner