Process to Decrease or Eliminate Corrosion from the Decomposition of Halide Containing Olefin Cataysts

Abstract

A process is provided to inhibit or limit the decomposition of a halide-containing olefin oligomerization catalyst system during recovery of an oligomerization product. The process includes deactivation of an olefin oligomerization catalyst system present in an olefin oligomerization reactor effluent stream by contact with an alcohol under conditions that minimize potential for deactivated catalyst system decomposition. Such conditions include minimization of the water content of the deactivation agent and concentration of the deactivation agent.

What is claimed is: 
     
         1 . A process to deactivate a halide-containing olefin oligomerization catalyst system and inhibit or limit the decomposition of the deactivated catalyst system during recovery of an olefin oligomerization product comprising the steps of:
 a) forming an intermediate stream by contacting an olefin oligomerization reactor effluent stream which comprises one or more olefin products, the catalyst system, and heavies with an alcohol that is soluble in any portion of the reactor effluent stream thereby deactivating the catalyst system; and   b) separating the intermediate stream into at least one product stream comprising the olefin oligomerization product and at least one heavies stream, wherein separating the intermediate stream comprises distilling a material, wherein distilling the material comprises passing the material through a reboiler, wherein the material is maintained below about 190° C.   
     
     
         2 . The process of  claim 1  wherein the material is maintained below about 185° C. 
     
     
         3 . The process of  claim 1  wherein the material is maintained below about 175° C. 
     
     
         4 . The process of  claim 1  wherein distilling the material comprises passing the material through at least two distillation stages. 
     
     
         5 . The process of  claim 1  wherein the alcohol has a boiling point different from at least one of the one or more olefin products in the reactor effluent stream. 
     
     
         6 . The process of  claim 1  wherein the alcohol has 6 or more carbon atoms per molecule. 
     
     
         7 . The process of  claim 1  wherein the alcohol is selected from the group of 1-hexanol, 3-hexanol, 2-ethyl-1-hexanol, 3-octanol, 1-heptanol, 2-heptanol, 3-heptanol, 4-heptanol, 2-methyl-3-heptanol, 1-octanol, 2-octanol, 4-octanol, 7-methyl-2-decanol, 1-decanol, 2-decanol, 3-decanol, 4-decanol, 5-decanol, 2-ethyl-1-decanol, and mixtures thereof. 
     
     
         8 . The process of  claim 1  wherein the alcohol is selected from the group of diols and polyols. 
     
     
         9 . The process of  claim 1  wherein the catalyst system comprises: a chromium source; a pyrrole-containing compound; and a metal alkyl comprising an alkylaluminum compound, a halogenated alkylaluminum compound, or combinations thereof. 
     
     
         10 . The process of  claim 9  wherein the alcohol is added in an amount to effect a mole alcohol to mole aluminum ratio between about 2.5 and about 1.5. 
     
     
         11 . The process of  claim 1  wherein the reactor effluent stream further comprises an organic diluent and one or more unreacted olefins. 
     
     
         12 . The process of  claim 1  wherein the catalyst system comprises a halogenated alkylaluminum compound. 
     
     
         13 . The process of  claim 1  wherein the catalyst system comprises a halide compound and a metal alkyl compound. 
     
     
         14 . The process of  claim 1  wherein the catalyst system comprises a mixture of an alkylaluminum compound and a halogenated alkylaluminum compound. 
     
     
         15 . The process of  claim 14  wherein the alkylaluminum compound comprises triethylaluminum. 
     
     
         16 . The process of  claim 14  wherein the halogenated alkylaluminum compound is diethylaluminum chloride. 
     
     
         17 . The process of  claim 9 , wherein the alkylaluminum compound comprises triethylaluminum, wherein the halogenated alkylaluminum compound comprises diethyl aluminum chloride, wherein the alcohol is 2-ethyl-1-hexanol, and wherein the olefin product comprises 1-hexene. 
     
     
         18 . The process of  claim 1   wherein the catalyst system comprises active metal alkyl units, and   wherein the alcohol is present in an amount greater than 0.1 and less than about 1.8 equivalents per equivalent of active metal alkyl units.   
     
     
         19 . The process of  claim 1  wherein the olefin oligomerization product comprises one or more olefin trimers. 
     
     
         20 . A process to deactivate a halide-containing olefin oligomerization catalyst system and inhibit or limit the decomposition of the deactivated catalyst system during recovery of an olefin oligomerization product comprising the steps of:
 a) forming an intermediate stream by contacting an olefin oligomerization reactor effluent stream which comprises olefin product(s) and catalyst system with an alcohol that is soluble in any portion of the reactor effluent stream thereby deactivating the catalyst system; and   b) separating the intermediate stream of step (a) into at least one olefin oligomerization product stream;   wherein the separation of step (b) comprises a distillation comprising a reboiler and material passed through the reboiler maintained below about 190° C.   
     
     
         21 . A process to deactivate a halide-containing olefin oligomerization catalyst system and inhibit or limit the decomposition of the deactivated catalyst system during recovery of an olefin oligomerization product comprising the steps of:
 a) forming an intermediate stream by contacting an olefin oligomerization reactor effluent stream which comprises olefin product(s), catalyst system, and heavies with an alcohol that is soluble in any portion of the reactor effluent stream thereby deactivating the catalyst system; and   b) separating the intermediate stream of step (a) into at least one olefin oligomerization product stream and at least one heavies stream;   wherein the separation of step (b) comprises a distillation comprising a reboiler and material passed through the reboiler maintained below about 190° C.,   wherein the catalyst system comprises active metal alkyl units, and   wherein the alcohol is present in an amount greater than 0.1 and less than about 1.8 equivalents per equivalent of active metal alkyl units.   
     
     
         22 . A process of  claim 21 , wherein the separation comprises at least two distillation stages and material passed through each reboiler is maintained below about 190° C.