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United States Patent Office Patented Sept 3,271,380 United States Patent Office Patented Sept. 6, 1966 2 move catalyst residues without inhibition of the removal PROCESS FOR CATALYSTRESIDUE327380 REMOVAL by undesirable hydrogen halides. Richard E. Dietz, Bartlesville, Okla., assignor to Phillips Other objects, aspects and the several advantages of the Petroleum Company, a corporation of Delaware invention will be apparent to those skilled in the art in No Drawing. Filed Apr. 1, 1963, Ser. No. 269,769 view of the following disclosure and the appended claims. 15 Claims. (C. 260-93.7) In accordance with the presence invention, I have now discovered that a major portion of the metallic catalyst This invention relates to the removal of catalyst resi residues contained in olefin polymers can be removed dues from polymers. In one aspect, this invention by treatment with (a) a halogen-containing epoxide hav relates to the removal of catalyst residues by utilizing a ing the general formula halogenated epoxide treatment of a polymer. In another O aspect, this invention relates to the removal of catalyst / N residues by utilizing a combination of a halogenated ep R-g-g-R oxide and a dicarbonyl compound as a treating agent for ly R the polymer. A further aspect of this invention relates 15 wherein R and R' are selected from the group consisting to the removal of catalyst residues by utilizing a combina of hydrogen and the nonsubstituted, epoxy-substituted, tion of a halogenated epoxide and a solid adsorbent bed and halogen-substituted alkyl, cycloalkyl, aryl, alkyl treatment of a polymer. A still further aspect of this cycloalkyl, cycloalkylalkyl, alkaryl, aralkyl, cycloalkyl invention relates to the removal of catalyst residues by aryl, and arylcycloalkyl radicals; R and R' can be joined utilizing a combination of a halogenated epoxide, a di 20 to form carbocyclic groups; and the molecule contains 2 carbonyl compound and a sorbent bed treatment of the to 20 carbon atoms, 1 to 3 halogen atoms, and 1 to 3 oxy polymer. gen atoms; (b) the halogen-containing epoxides of (a) Various reactions for polymerizing olefins are described plus a dicarbonyl compound containing the group in literature, and the polymerizations usually are carried O O out in the presence of a catalyst. One such procedure 25 | for the production of olefin polymers involves contacting C-CH-C- the monomer(s) with a catalyst system comprising a com (c) the halogen-containing epoxides of (a) plus a solid pound of a metal of Group IV, V, VI or VIII and a com adsorbent bed; or (d) the combination of the compounds pound selected from the group consisting of organometal of (b) and a solid adsorbent bed. compounds, metal hydrides and metals of Group I, II or 30 By the method of this invention the polymer is con III of the Periodic System. One of the problems encoun tacted with the halogen-containing epoxide in a hydro tered with polymers prepared by such processes concerns carbon slurry in an amount of from 1 to 5 times the the presence of catalyst residues, or ash-forming ingredi stoichiometric amount calculated on the basic of n gram ents, in the polymer. The "ash content” refers to the amols of treating agent per gram atom of total metal in inorganic constitutes which are present in the polymer 35 the catalyst charged, where n is the valence of the in unidentified form and which produce ash when the metal(s) in the catalyst, after which the system is heated polymer is burned. The presence of these catalyst resi to a temperature in the range of between 100 and 200 F. dues in the polymer adversely affects the color and heat for from 0.25 to 5.0 hours. When the hydrocarbon dil stability of the polymer as well as its electrical proporties. uent is the polymerization monomer, such as for example In addition, where metal halides are present in the cata 40 propylene, the temperature obviously will not exceed lyst, the use of a treating agent such as dicarbonyl com the critical temperature thereof. pounds containing the group Frequently it may be desirable to drain residual mono O O mer and/or other diluent from the system, wash the poly mer with hydrocarbon, and treat the washed polymer in -C-CH-C- 45 clean hydrocarbon, e.g. in additional monomer. By so results in reaction of the treating agent with the metal operating, the amount of treating agent will be substan halide with the evolution of a hydrogen halide. This is tially reduced since soluble residues in the diluent are most usually hydrogen chloride since metal chlorides are removed prior to treatment. usually employed as catalyst. HCl generation can lead When a dicarbonyl-containing compound is used in con to significant operating problems, especially in commercial 50 junction wtih the halogen-containing epoxide treatment, equipment, in the nature of corrosion of conduits and ves the dicarbonyl compound is combined with the halogen 'sels. Moreover, only moderate rates of extraction of containing epoxide compound, which acts as an adjuvant catalyst residues are obtained when dicarbonyl-type che for the dicarbonyl chelator. In many instances, the lating agents are used to sequester the catalyst residues. amount of chelating agent necessary to reduce catalyst Also, it is believed that, at least in some instances, the 55 residues to acceptable levels can be reduced; thus the ad presence of hydrogen chloride may tend to inhibit the juvant operates to enhance the effectiveness of the che chelating reaction. lating agent, in one aspect by acting as a scavenger for the It is thus an object of the present invention to provide hydrogen halides liberated from the reaction of catalyst an improved process for producing polymers of olefins with the chelating agents. When a diketone and a halo having a low ash content. 60 gen-containing epoxide are used together, the diketone is Another object of the present invention is to provide used in an amount of from 1 to 5 times the stoichiometric a process for treating polymers to remove catalyst residues amount calculated on the basis of m/2 gram mols of associated therewith. diketone per gram atom of total metal, where m is the Another object of the invention is to provide a process coordination number of the metal(s) in the catalyst, for polymerizing olefins wherein the polymerization ef 65 and the halogen-containing epoxide is used in an amount fluent containing liquid monomer and polymer in sus of from 1 to 5 times the stoichiometric amount calculated pension is treated to remove catalyst residues. on the basic of one gram mol of halogen-containing ep A further object of the invention is to provide a method oxide per gram atom of halogen in the catalyst. for removing catalyst residues from a polymer wherein When an adsorbent bed is used in conjunction with a halogen is a part of the catalyst complex. either the epoxide compound alone or the combination A still further object of the invention is to provide a of epoxide and a dicarbonyl compound, a small quantity process for treating a stream containing polymer to re of epoxide or of epoxide plus diketone, calculated as 3,271,380 3 4. indicated above, is mixed with the polymer solution by p-tolylscandium dibromide, stirring the mixture for about 0.25 to 5.0 hours at a tem diphenylscandium chloride, perature level at which the polymer remains in solution, trimethyltyttrium, generally in the range of 100 to 300 F., then passing trimethylaluminum, the solution over a bed of an activated adsorbent, e.g. triethylaluminum, clay (bentonite, kaolinite, and the like), diatomaceous triisobutylaluminum, earth (kieselguhr and the like), bauxite, alumina, titania, tri-n-butylaluminum, magnesia, silica, activated carbon and the like, at a tri-n-pentylaluminum, similarly elevated temperature. Prior to contacting with trisooctylaluminum, the halogen-containing epoxide-polymer solution, the O tri-n-dodecylaluminum, adsorbent is activated by heating in a stream of air at a triphenylaluminum, temperature in the range of 500-1000 F. for about 10 triethylgallium, minutes to 6 hours and purging with nitrogen or other triphenylgallium, inert gases. Contact time of the solution with the ad tricyclohexylgalium, sorbent is in the range of about 1 to about 20 minutes, 5 tri-n-butylindium, From the adsorbent treatment the solution is passed to triethylthallium, a recovery zone where the polymer is isolated by suitable diethylaluminum hydride, means such as by stripping or flashing to remove solvent methylaluminum dichloride, therefrom, dimethylaluminum chloride, The present invention is applicable to the treatment of 20 ethylaluminum dichloride, polymers which are prepared by polymerizing olefinic diethylaluminum chloride, compounds including mono-1-olefins and diolefins con di-n-butylaluminum bromide, taining from 2 to 20 carbon atoms. Examples of such isooctylaluminum diiodide, monomers include di-n-propylgallium fluoride, ethylene, eicosylgallium dibromide, propylene, ditetradecylgallium fluoride, 1-butene, dicyclohexylgallium chloride, 1-pentene, diphenylgallium bromide, 3-methyl-1-butene, diphenylindium chloride, 1-hexene, 30 dioctylindium fluoride, 1-heptene, cyclohexylindium dibromide, 1-octene, 3-methylcyclohexylaluminum dichloride, 4-methyl-1-pentene, 2-cyclohexylethylgallium dichloride, 3-methyl-1-hexene, p-tolylberyllium iodide, 4-vinylcyclohexene, di-(3-phenyl-1-methylpropyl)indium fluoride, 1-eicosene, 2-(3 - isopropylcyclohexyl)-ethylthallium dibromide, and 4-ethyl-1-octadecene, the like. 6-methyl-1-dodecene, The metal hydrides can include, as specific examples, 1,3-eicosadiene, 40 aluminum hydride, lithium aluminum hydride, barium hy 4,6-diethyl-1,3-decadiene, dride, gallium hydride, indium hydride, sodium hydride, 4,5-dimethyl-1-octene, potassium beryllium hydride. 1-hexadecene, The metals of the first, second and third groups are 1,3-butadiene, applicable as a class, the most important members being isoprene, Sodium, magnesium, and aluminum.
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