Method of oxychlorination utilizing split feeds

Abstract

A method for oxychlorinating ethylene to ethylene dichloride utilizing a two reactor oxychlorination system in which the oxygen and hydrogen chloride feeds are split between the reactors such that the volume ratio of HCl fed to the first reactor to the HCl fed to the second reactor, and the volume ratio of O2 fed to the first reactor to the O2 fed to the second reactor are both in the range of about 50:50 to about 99:1.

We claim: 
     
       1. A method of oxychlorination comprising: providing an oxychlorination reactor system having a first reactor in fluid communication with a second reactor, said reactor system for converting ethylene, hydrogen chloride, and oxygen into a ethylene dichloride product stream from said second reactor;   feeding a quantity of hydrogen chloride to said reactor system;   feeding ethylene to said reactor system in less than 5% stoichiometric excess to said quantity of hydrogen chloride;   feeding a quantity of oxygen to said reactor system in stoichiometric excess to said quantity of hydrogen chloride;   reacting ethylene, hydrogen chloride and oxygen in said first reactor by contacting ethylene, hydrogen chloride, and oxygen together in the presence of an oxychlorination catalyst to produce a first reactor product stream containing ethylene;   reacting hydrogen chloride, oxygen and the first reactor product stream in said second reactor by contacting said first reactor product stream, hydrogen chloride and oxygen together in the presence of an oxychlorination catalyst to produce said ethylene dichloride product stream; and   recycling ethylene from said ethylene dichloride product stream to provide recycled ethylene to said first reactor;   wherein the ratio of the hydrogen chloride fed to the first reactor to the hydrogen chloride fed to the second reactor is in the range of about 50:50 to about 99:1, and wherein the ratio of the oxygen fed to the first reactor to the oxygen fed to the second reactor is in the range of about 50:50 to about 99:1.   
     
     
       2. The method of claim 1 wherein the ethylene, hydrogen chloride and oxygen are contacted together in the presence of a copper containing catalyst. 
     
     
       3. The method of claim 1 wherein the volume ratio of the hydrogen chloride fed to the first reactor to the hydrogen chloride fed to the second reactor is in the range of 50:50 to 80:20, and wherein the volume ratio of the oxygen fed to the first reactor to the oxygen fed to the second reactor is in the range of 50:50 to 80:20. 
     
     
       4. The method of claim 1 wherein the volume ratio of the hydrogen chloride fed to the first reactor to the hydrogen chloride fed to the second reactor is in the range of 50:50 to 75:25, and wherein the volume ratio of the oxygen fed to the first reactor to the oxygen fed to the second reactor is in the range of 50:50 to 75:25. 
     
     
       5. The method of claim 1 wherein the operating temperatures within the first reactor and the second reactor are in the range of from 180° C. to 350° C. 
     
     
       6. The method of claim 1 wherein the percent of total HCl fed to the first reactor is about the same as the percent of total O2 fed to the first reactor. 
     
     
       7. The method of claim 1 wherein the percent of total hydrogen chloride fed to the first reactor divided by the percent of total oxygen fed to the first reactor is from about 0.95 to about 1.5. 
     
     
       8. The method of claim 3 wherein the percent of total hydrogen chloride fed to the first reactor divided by the percent of total oxygen fed to the first reactor is from about 0.95 to about 1.5. 
     
     
       9. The method of claim 1 further comprising: (c) contacting the second reactor product stream with water to form a quenched product stream.   
     
     
       10. The method of claim 9 further comprising: (d) contacting the quenched product stream with a caustic to form a washed stream.   
     
     
       11. The method of claim 10 further comprising: (e) condensing the washed stream to form an ethylene dichloride product stream and a recycle gas stream.   
     
     
       12. The method of claim 11 further comprising: (f) recycling the recycle gas stream to the first reactor.   
     
     
       13. The method of any one of claims 1 to 12 further including the step of recycling ethylene from said ethylene dichloride product stream to provide recycled ethylene to said second reactor wherein said recycled ethylene is split between said first reactor and said second reactor. 
     
     
       14. The method of any one of claims 1 to 12 wherein the step of feeding ethylene to said reactor system in less than 5% stoichiometric excess to said quantity of hydrogen chloride feeds said ethylene to said first reactor and said second reactor in split fashion. 
     
     
       15. The method of any one of claim 14 further including the step of recycling ethylene from said ethylene dichloride product stream to provide recycled ethylene to said second reactor wherein said recycled ethylene is split between said first reactor and said second reactor.