Reduction of fouling in high pressure reactors

Abstract

The Application of equations of state to experimental and literature data permits the formation of a model and phase diagram(s) that show under what conditions polyethylene is likely to precipitate out of a high pressure solution of polyethylene in supercritical ethylene. This then permits a better definition to run a high pressure reactor to reduce the likelihood of phase separation, loss of cooling and potentially decomposition of the reactor contents.

1 - 11 . (canceled) 
     
     
         12 . A method of operating a polymerization of a mixture of not less than about 80 wt % ethylene and up to about 20 wt % of one or more C 3-8  alpha olefin monomers at a pressure from about 100 to about 350 MPa and a conversion wherein during the initial conversion of up to about 10 wt % of polymer wherein the temperature is maintained above about 125° C. [to about 135° C.]. 
     
     
         13 . The method according to  claim 12 , wherein the pressure is from about 150 to about 325 MPa. 
     
     
         14 . The method according to  claim 13 , wherein the initial conversion to polymer is up to about 7 wt %. 
     
     
         15 . The method according to  claim 14 , wherein the temperature is above about 130° C. 
     
     
         16 . The method according to  claim 15  wherein the pressure is from about 200 to about 300 MPa. 
     
     
         17 . The method according to  claim 16 , wherein the temperature is above about 128° C.