Wacker-chemie Gmbh

Peter Hirschmann

Ludwig Schmidhammer

Rudolf Strasser

Gerhard Dummer

Franz Haunberger

Hermann Klaus

Klaus-Peter Mohr

Herbert Patsch

Gerhard Stettner

The invention is a multi-stage process for purifying hydrogen chloride containing acetylene and ethylene, from pyrolysis of 1,2-dichloroethane to provide highly pure hydrogen chloride for use in the preparation of silicon compounds. In the first stage, unsaturated by-products are chlorinated by reaction with an excess of chlorine gas. In the second stage, the unreacted chlorine gas remaining in the hydrogen chloride is reacted with an excess of defined olefins or chloroolefins and the hydrogen chloride is separated from the chlorination products and the excess olefins or chloroolefins by low-temperature rectification under pressure.

Process for purifying hydrogen chloride from pyrolysis of

In a process for the purification of hydrogen chloride from the pyrolysis of 1,2-dichloroethane, optionally after a preceding step of acetylene removal by selective hydrogenation under specific conditions followed by rectification of the resulting mixture to obtain hydrogen chloride containing at most 5 ppm of unsaturated hydrocarbons and at most 5 ppm of chlorinated hydrocarbons.

Process for purification of HCl from pyrolysis of EDC

In a process for preparation of 1,2-dichloroethane by chlorination of ethylene-containing reaction vent gases from the oxychlorination of ethylene in the presence of a catalyst carrier impregnated with metal compounds wherein the waste from the oxychlorination stage are chlorinated, the improvement comprising preheating the ethylene-containing waste gases to at least 50.degree. C. and then chlorinating the ethylene at 100.degree. to 300.degree. C. at a pressure of 1 to 7 bar with a space velocity of 100 to 5000 h.sup.-1 related to standard conditions in the presence of at least one metal compound selected from the group consisting of chlorides and oxides of manganese, nickel and cobalt supported on a catalyst carrier with reduced formation of oxychlorinated by-products.

Process for oxychlorination of ethylene

In a method of recovering heat from flue gas resulting from the combustion of chlorinated organic compounds at 900.degree. to 1300.degree. C. at a pressure of 0.9 to 1.5 bar absolute whereby the flue gas is cooled with the recovery of heat and hydrogen chloride is processed, the improvement comprising (a) cooling the flue gas in a first step to a temperature of 250.degree. to 350.degree. C. with a contact time of 0.05 to 0.15 seconds, (b) cooling the flue gas in a second step to a minimum of 140.degree. C. with a contact time of 1.3 to 2.0 seconds, the cooling medium in both stages being water flowing at an initial temperature of 100.degree. to 140.degree. C. in step (b) counter to the flue gas flow direction and added to cooling stage (a) at a temperature of 200.degree. to 220.degree. C. and (c) cooling the flue gas in a third stage to its dew point and scrubbing it with water to recover the hydrogen chloride therein in solution.

Growing community of inventors

Burghausen, Germany

Peter Hirschmann