Deactivating and removing aluminum and titanium contaminant from Ziegler-Natta polymerization mixtures

Abstract

A polymerization reaction product comprising a solution of a poly(1-alkene) and a hydrocarbon polymerization solvent is purified of Ziegler-Natta aluminum and titanium containing catalyst residue by treating with flux-calcined diatomite to deactivate and insolubilize the aluminum and titanium and filtering out the insolubilized aluminum and titanium.

We claim: 
     
       1. A method for the deactivation and separation of residual catalyst from a solution containing a liquid poly(1-alkene) which is the reaction product of the polymerization of a 1-alkene having from five to 20 carbon atoms in a hydrocarbon polymerization solvent in the presence of a catalytic amount of an organoaluminum compound and a titanium compound which comprises the steps of adding a minor amount of a flux-calcined diatomite to the poly(1-alkene) polymerization solution and filtering out the flux-calcined diatomite and the insolubilized catalyst metals from the liquid poly(1-alkene) solution. 
     
     
       2. A method in accordance with claim 1 in which the flux-calcined diatomite is added in an amount of at least about 0.005 weight percent of the poly(1-alkene) solution. 
     
     
       3. A method in accordance with claim 1 in which the flux-calcined diatomite is added in an amount about equal to the weight of the catalyst. 
     
     
       4. A method in accordance with claim 1 in which the flux-calcined diatomite has a mean particle size of at least about 5.5 microns. 
     
     
       5. A method in accordance with claim 1 in which the flux-calcined diatomite has a mean particle size of at least about 10 microns. 
     
     
       6. A method in accordance with claim 1 in which the flux-calcined diatomite has a mean particle size of at least about 20 microns. 
     
     
       7. A method in accordance with claim 1 in which the flux-calcined diatomite is added in an amount of at least about 0.02 weight percent of the poly(1-alkene) solution. 
     
     
       8. A method in accordance with claim 1 in which the organoaluminum compound has the general formula AlR 3   -n  X n  where n is from 0 to about 2, R is alkyl having one to about 20 carbon atoms and X is chlorine, bromine or hydrogen. 
     
     
       9. A method in accordance with claim 8 in which n is 0 and R is alkyl having one to four carbon atoms and the titanium compound is a titanium trichloride composition. .Iadd. 10. A method for the deactivation and separation of residual catalyst from a solution containing a poly(1-alkene) dissolved in a hydrocarbon polymerization solvent in the presence of a catalytic amount of an organoaluminum compound and a titanium compound which comprises the steps of adding a minor amount of a flux-calcined diatomite to the poly(1-alkene) polymerization solution and filtering out the flux-calcined diatomite and the insolubilized catalyst metals from the liquid poly(1-alkene) solution. .Iaddend.