Патент USA US2409374код для вставки
(1 Patented Oct. 15, 1946 2,409,372 qUNlTED STATES PATENT OFFICE REMOVAL OF ORGANIC FLUORINE Maryan I’. Matuszak, Bartlesville, Okla, assignor to Phillips Petroleum Company, a corporation of Delaware Application January 3.1944, ‘ No Drawing‘. Serial No. 516,852 ' 10 Claims. (01. 196-411 . r t , 1 v 2 a , or otherwise. The other method involves treat ment with a solid porous. contact material under conditions binding the ?uorine so that the treated hydrocarbon material is not only freed from a embodiment it relates to the removal from hydro carbon materials of ?uorine-containing organic 01 substantial part or all of the organically com bined ?uorine but is also recovered without being compounds which are present in relatively minor contaminated with free hydrogen ?uoride. The amounts. In a more speci?c embodiment my in latter process is described in the copending appli vention relates to the removal of at least a major cation of Frederick E, Frey, Serial Number portion of organically bound ?uorine from hydro 398,361, ?led June 16, 1941, now U. S. Patent carbon materials containing organically bound 2,347,945, issued May 2, 1944. Among the con ?uorine in an amountnot greater than about 2 tact materials which may be used in such a proc~ per cent by weight, and often in an amount not ess are those catalytically active for hydrogena-. greater than about 0.1 to about 0.5 per cent by This invention relates to the treatment of or ganic materials to remove organic ?uorine-con taining compounds therefrom. In one general weight. The invention is particularly applicable tion and dehydrogenation reactions, preferably to such ?uorine removal as carried out with the 15 the oxides of various metals, such as the oxides of metals chosen from the group consisting of aid of naturally occurring minerals containing aluminum, titanium, zirconium, hafnium, tho silica as an impurity. In the manufacture of hydrocarbons by proc esses in which ?uorine-containing catalysts are used, small proportions of organic ?uorine-con taining lay-products are often formed. Processes to which my invention may be generally applied involve the alkylation of relatively low-boiling hydrocarbons with ole?ns, alcohols, ethers, alkyl halides, and the like, to produce higher-boiling hydrocarbons in the presence of catalysts com prising one or more such ?uorine compounds as hydro?uoric acid, boron tri?uoride, antimony tri rium, vanadium, chromium, moIy-bdenumtung sen, uranium, manganese, iron, cobalt, nickel, 30 or the like, alone or in admixture, synthetically produced or in naturally occurring forms such as ores. Due primarily to their low cost and avail ability, the naturally occurring ores are ordinarily - used, and bauxite has been found to be particu larly advantageous. Other naturally occurring oxides such as limonite, manganite, baddeleyite, brookite, brucite, diaspore, dysanalite, .gibbsite, goethite, heusmannite, huebnerite, ilmenite, lep ?uoride, complexes of these with other materials idocrite,,rutilefspinel', valentinite, etc., are also such as are formed by boron tri?uoride and water, ‘ useful.__jr various organic acids, alcohols, and acids of phos ‘_ - ' _, Unfortunately, natural contact materials of this type contain up to as, much as 20 per cent by weight Or vmore of siliceous material, most gener; phorus. My invention may also be applied to processes wherein such low-boiling hydrocarbons are .isomerized in the presence of such catalysts. The exact nature and composition of the organic containing by-products which are formed and acid believed to be formed by decomposition of which are present as impurities in the desired the organic ?uorinecompounds before such'hy product has not been de?nitely established, al though they are believed to be predominantly alkyl and/or aryl ?uorides, but it is known that they are not completely removed by washing the products with alkali solutions, and that they tend .to decompose at elevated temperatures such as those employed in fractional distillation of the products, thereby forming hydro?uoric acid which is corrosive, especially in the presence of moisture. drogen ?uoride becomes bound by the porous con tact material. At anyrate, the formation of sili con tetra?uoride occurs. This silicon tetrafluo ride is highly objectionable because it contami nates the hydrocarbon material, and because con tact of it with moisture produces hydro?uoric ’ same time deposits gelatinous silicic acid which accumulates , until the equipment is plugged. In gases they may thus cause corrosion of han Moreoventhe loss of ?uorine, in the form of sili 'dling equipment; in liquid motor fuel hydrocar con tetra?uoride, is economically undesirable. ‘ bons they are undesirable for reasons that are An object of this invention is to effect removal of organically combined ?uorine from hydrocar obvious. ' ' ‘ ‘ Two general methods of removing-such organic combined ?uorine are available. One involves a decomposition of the same under‘conditions liber ating free hydrogen ?uoride, which is subsequent ly removed from the hydrocarbons by distillation ally silica, as an impurity. In'actual practice, such silica apparently reacts with hydro?uoric acid, Whichis exceedingly corrosive, and at the bon'materials containing the same. _ ' Anotherobject is to eifect substantially com plete removal of ?uorine from hydrocarbon ?uids containing organic ?uorine compounds‘ as im purities. ' . ‘ . » 2,409,372 4 3 monia thus recovered may be reused in the proc Another object is to remove organic ?uorine ess of the present invention. from hydrocarbon materials that have been pre In carrying out a treatment in accordance with pared by a process in which a ?uorine-containing my invention, the hydrocarbon material, contain catalyst is used. ing a small added proportion of ammonia, is Another object of the invention is to avoid the passed in the liquid or vapor phase, preferably formation of silicon tetrafluoride in processes in the liquid phase, through the contact mass, wherein fluorineeconta-ining material is contacted which is preferably bauxite, at a space velocity with bauxite or other naturally occurring metal of approximately 1 to 10 volumes of liquid per oxide. Further objects and advantages of my inven 10" volume of contact mass per hour and at a tem perature-in the. range between about 100 and tion will be apparent, to one skilled: inthearth 350° F. The pressure on the hydrocarbon ma from the accompanying disclosure and discussion. According to this invention,v in preferred-‘em bodiment, a small proportion of ammonia, usu terial, although not critical, is preferably be tween about*15‘~ and 500 p. s. i. (pounds per square inch), and is“ chosen to give vapor phase, mixed ally less than 1 per cent by weight, and prefer ably not more than approximately the. stoichie-J phase, or liquid phase operation as desired.‘ In_order to illustrate certain features of my ometric equivalent of the ?uorine, such aszior example 0.001 to 0.01 per cent by weight, is added. ' invention,4the following examples are offered. It tact‘ material of‘ the’ nature described. Hydroe fluoric acid present‘ in theihydrocarbon material will of course be understood that the data given are only exemplary in nature, and hence are not to be. so1 construed as to unduly limit the inven tion'. or formed from the organic- ?uorine is" believed to react with the’ ammonia‘ to form ammonium In an exploratory'experiment, 03 gram of am moniawas‘ mixed with 48.5‘ grams of n-butane to the hydrocarbon material before contacting ' with the silicon-containing bauxite or other con- _ fluoride and/or ammonium acid ?uoride, where :5 containing 0.069‘ percent by~weight of silicon tetra?uoride- After-the mixture had stood over byj;it is prevented‘ from forming silicon» tetra night',.the: butane‘ contained’ only 0.011 per cent ?uorid'e: Furthermore, any silicon tetra?uoride by-weightof’sili-con tetra?uoride; indicating that which maybe fbrmedisoconverted to" ammonium 84' per‘ cent‘ of the silicon tetra?uori'cl'e had been ?iiosiiicate‘," which‘ is relatively‘ less volatile; so‘ thafthe" hydrocarbon" material remains free : converted to" compounds of- lower volatility by- re action: with the ammonia. from this objectionable compound‘. The‘ ammo In another exploratory‘ experiment, a‘ stream nium salts. are retained by the contact‘ mate' of n-butane containing'0.038 per cent by weight rial'. The‘ addition‘ of ammonia: to. the‘ hydro of? ammonia waspassed through spent bauxite carb'on-st'ream has'the-pra‘ctical advantages that pretreatment of'the bauxite is" unnecessary and -'-‘-'I fromthe bauxite treater of a commercial hydro ?uoric. acid alkylation plant‘ at a space velocity that" the ammonia can‘ be added in' controlled of 1.4 liquid volumes per volume of catalyst per proportion in‘ accordance with need as‘ shown by hour and at a temperature of'180°' F; After am analysis‘ of‘ the effluent hydrocarbon material. monia amounting to 3.4 percent by‘ weight of the Any ammonia in' the hydrocarbon stream‘ inex cess of‘ that‘ required for‘ reaction with'hydro 4:1) used bauxite had been adsorbed, a stream of'n butane containing’ 0.0025 per cent by weight of ?uoricacid' and/or silicon tetrafluoride; appears silicon'tetrafiuoride was passedv through the am to‘ be adsorbed by the bauxite and/or‘ the. de monia-containing bauxite at’ a- space velocity of posited ammonium salt' or salts, so. that“ the 1.8lto 2.3 volumes‘ of 'liquid pervolume of contact diluent hydrocarbon stream is' ammonia-free. When the bauxite‘ has become spent; the passage 45 mass“ per hour. Substantially complete removal of' hydrocarbon materials is interrupted; and‘the of‘ the silicon tetra?uoride. occurred. bauxite is revivi?ed" or" replaced. Ingran illustrative speci?c example, a debutan It will‘ be appreciated that natural‘ ores’ con izer overhead e?luent- from the hydro?uoric‘ acid alkylation of isobutane with butenes is mixed taining relatively high proportions of silica. are more readily available and much cheaper. than 50 with 0.005 per cent‘ by weight of ammonia, and the mixture is! passed over bauxite; The rate of those- having‘. an unusually“ low-v silica: content. Such advantages of high-silica ores are even more ?ow of’_ the hydrocarbon is from 2 to 5 volumes pronounced when_ comparedv with synthetically of-hydrocarbon per volumeof' catalyst per hour; the-temperatureis'maintained at 150 to 200° F.'.; produced materials. My' invention“ may be vap- ' the‘ pressure is sufficient to maintain the hydro pli'edeto treatment with materiaisv of' lower high carbon in the liquid phase. Substantially com silica-content to advantage, and the'choice of particular" contact" material will be largely a plete removal of the organic ?uorine oc.curs;.and matter ‘of’ economic‘ consideration. the e?luent hydrocarbon material is free from When'the'spent contact‘mass'isi to be revivi?ed‘, silicon tetra?uoride. When spent, the contact it‘is-heated‘ to-an elevated temperature at which ammonia and‘ ammonium‘ salts are‘ volatilized'. The vol'atilizationmay be“ aided‘ by' a flowing. at mosphere of‘ an" inert carrier gas. Usually, volatili'zat'i'onv of ‘all the ammonia and ammonium salts need not. be practiced. During the. revivi ?cation some. silica may. be removed as silica tet ra?uoride. and/or ammonium.?uosilicate;. in. fact, insome instances, after revivi?cationthebauxite mass is heated in a stream of gas, such as natural gas or butane, to remove ammonia and ammoni um' compounds; which are collected and used for any ‘suitable purpose. The revivi?ed contact mass is suitable for re-use. Any ammonia obtained by the revivi?cationstep. isrecycl'ed. to the process. It..will,readily, be, appreciatedthat. while cer tain-speci?c aspects. of the. invention have been described .in- considerable; detail, the. invention is or.~other catalyst: may contain: so little: silica that 70 not to be so construed as to be unduly limited subsequent use of. itrmay bemadeein‘theordinary thereby, and’ various modi?cations. and‘ embodi manner: without‘ use. of ' ammonia. The gases: and ments; may be practiced, by one skilled'inv the fumes; eifluent from‘ the revivi?cation. may‘ be art; by following. the teachings of the. present passed tov a. recovery’ stepv for: recovery._of am disclosure. without departing from the spirit monia and/or other desired compounda. thereof‘ or from the scopeof'the- claims. 2,409,372 5 I claim: 6 , 5. The process of ‘claim 3, wherein said nat— urally-occurring solid metal oxide contact ma— _ 1. The process of removing organic ?uorine from hydrocarbon materials containing the same terial is bauxite. _ which comprises treating such hydrocarbon mae 6. The process of claim 3, wherein said nat terials with a solid contact material comprising urally-occurring solid metal oxide contact ma a metal oxide catalytically active for hydrogena terial is an oxide of an iron-group metal. tion and dehydrogenation reactions and contain '7. The process of claim 3, wherein said nat ing silica as an impurity, said treating being urally-occurring solid metal oxide contact ma conducted in the presence of added ammonia uné terial is iron oxide. der conditions producing a hydrocarbon ef?uent 10 8. The process of claim 3, wherein, when said of substantially reduced ?uorine content and contact material becomes incapable of removing substantially free from silicon compounds. _ ?uorine to a desired extent, said contact ma 2. The process of removing organic ?uorine terial is heated in a stream of inert gas to an from hydrocarbon materials containing the same, elevated temperature adequate to effect the vola' which comprises treating such hydrocarbon ma 15 tilization of at least a portion of the ammonium terials with a naturally-occurring solid metal ox compounds therefrom, and is then reused for said ide contact material active for removal of or- . ganically combined ?uorine from hydrocarbon materials and containing a minor amount of silica ?uorine removal. ‘ 9. In a process for the removal of organically combined ?uorine from a hydrocarbon material as an impurity, said treating being conducted in 20 containing the same, wherein such a material the presence of ammonia under conditions pro is contacted with bauxite containing siliceous ducing a hydrocarbon eiiluent of substantially impurities under conditions such that extensive reduced ?uorine content and substantially free chemicalv changes in said hydrocarbon material from silicon compounds. itself are not e?ected and such that the hydro 3. A process for treating a hydrocarbon ma 25 carbon effluent from said contacting is substan terial to remove organically combined ?uorine tially free of such organically combined ?uorine therefrom, which comprises subjecting a hydro but normally contains volatile compounds of sili carbon material, containing a minor quantity of con and ?uorine, the improvement which com organically combined ?uorine and also contain prises admixing with such hydrocarbon material ing ammonia in an amount substantially stoi 30 undergoing said contaoting a minor quantity of chiometrically equivalent to the ?uorine content ' ammonia at least stoichiometrically equivalent to thereof, to the action of a naturally-occurring the ?uorine content thereof. solid metal oxide contact material active for re— 10. The process of claim 9, wherein said hy moval of organically combined ?uorine from hy drocarbon material contains not over about 2 drocarbon materials and containing a minor 35 per cent by weight of ?uorine, is contacted in the amount of silica as impurity, under conditions liquid phase with bauxite at temperatures be such that extensive chemical changes in said hy- _ tween about 100 and about 350° F. at ?ow rates drocarbon material itself are not effected and between about 1 and about 10 volumes per vol such that the total effluent from. said treatment ume bauxite per hour, and in which a hydrocar is substantially free from ?uorine in any form 40 bon e?luent from said contacting is'obtained sub and from ammonia and ammonium compounds. stantially free from silicon and from ?uorine. 4. The process of claim 3, wherein said nat urally-occurring solid metal oxide contact ma— MARYAN P. MATUSZAK. terial comprises an alumina.