Integrated method for producing chlorine

Abstract

The invention relates to a process for preparing chlorine in three process steps, wherein a catalytic oxidation of hydrogen chloride to chlorine over a uranium oxide catalyst is performed in a first process step, the chlorine formed is at least partly removed in a second step, and an electrochemical oxidation of hydrogen chloride to chlorine is performed in a third process step.

1 . A process for preparing chlorine from a reaction mixture A comprising at least hydrogen chloride, comprising the steps of
 a) oxidizing hydrogen chloride with oxygen to chlorines in at least one first reaction zone in presence of a catalyst to obtain a product stream P 1 ,   b) at least partly removing the chlorine present in the product stream Pi from a) to obtain a product stream P 3 ,   c) electrochemically oxidizing the hydrogen chloride present in the product stream P 3  from b) in a second reaction zone, the product stream P 3  also comprising water, and in some cases also chlorine,   wherein the product stream P 3  from b) is fed directly to the reaction zone in c), and in that the catalyst in a) comprises a uranium compound.   
     
     
         2 . The process according to  claim 1 , wherein the catalyst comprises a support material. 
     
     
         3 . The process according to  claim 2 , wherein the support material is a uranium compound. 
     
     
         4 . The process according to  claim 1 , wherein the uranium compounds are uranium oxides, uranium chlorides and/or uranium oxychlorides. 
     
     
         5 . The process according to  claim 4 , wherein the uranium oxides are UO 3 , UO 2 , or UO is, or uranium oxides of a nonstoichiometric composition. 
     
     
         6 . The process according to  claim 5 , wherein the uranium oxides of nonstoichioetric composition are those with a uranium to oxygen ratio according to the formula UO x  of UO 21  to UO 5 . 
     
     
         7 . The process according to  claim 1 , wherein the step a) is conducted at temperatures above 350° C. up to temperatures of 800° C. 
     
     
         8 . The process according to  claim 1 , wherein a fractional condensation to obtain the product stream P 3  performed in step b), and from which a product stream P 2  comprising essentially chlorine is removed. 
     
     
         9 . The process according to  claim 8 , wherein the heat withdrawn from the product stream P 1  is used for the heating of the reaction mixture A in or upstream of reaction zone of the step a). 
     
     
         10 . The process according to  claim 1 , wherein step c) is performed with an oxygen consumption cathode.