US2467326A - Production of branched chain hydrocarbons catalyzed by friedelcrafts catalysts modified by boric acid - Google Patents

Description

Patented Apr. 12, 1949 um'rao "STATES-- PATENT OFFlCE 4 amuse PRODUCTION or naaivcrmn mm HrnaocAanoNs CATALYZED nrr'ampnncams CATALYSTS MODIFIED ar- BORIC ACID I Julian M. Mavity, Hinsdale, m, assignor to Uni-- versal Oil Products Company, Chicago, lll., a

corporation of Delaware No Drawing.

Application September 29, 1945, Serial No. 619,431

12 Claims. (Cl. 260-671) This invention relates to the treatment of organic compounds in the presence of a particular type of catalyst to produce compounds of branched carbon structure. The invention is more particularly concerned with the production of branched chain hydrocarbons by processes which utilize a catalyst prepared by reacting boric acid and 'a metal halide of the Friedel Crafts type.

The production of branched chain hydrocarbons may involve the isomerization of less branched into more Branched hydrocarbons, such as the isomerization of normal. butane to isobutane, the isomerlzation of more branched into less branched hydrocarbons, such as the conversion of dimethylcyclopentane into methylcyclohexane or the conversion of methylcyclopentane into cyclohexane, the alkylation of paramns, naphthenes, and aromatics, the deallrylation oi cyclic hydrocarbons including naphthenic and aromatic hydrocarbons. the polymerization of oleflns, and the like.

In one embodiment the present invention relates to a process for producing hydrocarbons of branched carbon structure which comprises subjecting a reactive hydrocarbon under conversion conditions to the action of a catalyst prepared by reacting boric acid and a metal halide of the Friedel-Crafts type with the evolution of hydrogen halide.

The hydrocarbons which may be utilized as starting materials for the process of the present invention comprise paraiilnic, oleilnic, naphthenic, and aromatic hydrocarbons. The paraffins and oieiins include both normal and branched chain isomers, and the naphthenes and aromatics comprise cyclic and alkylated cyclic hydrocarbons. The diil'erent types of hydrocarbons which may be converted into branched and more highly branched chain hydrocarbons according to the process of the present invention are hereinafter referred to more completely.

Aromatic hydrocarbons, such as benzene, toluone other allryl' benzenes, naphthalene, alkyl naphthalenes, other poly-nuclear aromatics, etc., which are alkylated by oleflnic hydrocarbons as hereinafter set forth, may be obtained from any source such as by distillation 0! coal, by the dehydrogenation of naphthenic hydrocarbons. by the dehydrogenation and cyciization of aliphatic hydrocarbons, etc.

Naphthenic hydrocarbons which may be alkylated or isomerized according to the present process occur generally in admixture with parafilns and aromatics in diiferent crude petroleums,

2 Of the different naphthenic hydrocarbons, also referred to as cycloparamns, the cyclop'en'tane, cyclohexane, alkyl cyclopentane and alkyl cyclohexane hydrocarbons are generally those which are isomerized or alkylated in the presence of a catalyst of the type herein described to produce naphthenic hydrocarbons of more highly branched chain structures. which areutilizable as constituents of high antihnock gasoline or for other purposes.

Normal paramnic hydrocarbons which may be converted into isoparamnic hydrocarbons by the present process comprise normal bu tane and higher boiling paraiilnic hydrocarbons of straight-chain structure. Similarly, mildly branched liquid paramns may be isomerized into more highly branched chain paraiiinic hydrocarbons with substantially higher antiknock value than the less branched compounds charged to the process.

Isobutane is the isoparaflin commonly subjected to alkylation although higher molecular weight isoparailins also react with oleflnic hydrocarbons under similar or modified conditions of operation to produce branched chain parafflnic hydrocarbons of higher boiling point than the isoparafiinic hydrocarbons charged to the process. 1

Olefinic hydrocarbons utilizable in the present process comprise mono-olefins having one double bond per molecule and poly-oleflns having more than one double bond per molecule. Mono-oleflns which may be polymerized or be utilized for alkylating isoparamnic, naphthenic, or aromatic hydrocarbons in the presence of the catalyst herein described are either normally gaseous or normally liquid and include ethylene, propylene.

butylenes, amylenes, and higher normally liquid oleflns, the latter including various polymers of normally gaseous oleflns. Cyclic oleflns such as cyclohexene may also be utilized, but'generally not under the same conditions of operation as those employed with non-cyclic oleflns. Other olefinic hydrocarbons utiliz'able in the present process include conjugated dicleflns such as butadiene and isoprene and also non-conjugated diolefins and other poly-oleflnic hydrocarbons containing more than 2 double bonds per molecule.

:Alkylation of saturated hydrocarbons, including isoparafllnic, naphthenic and aromatic hydrocarbons may also be eifected in the presence of the catalyst hereinafter described, by reacting with the saturated hydrocarbons a substance capable of producing olefinic hydrocarbons under 3 the conditions of operation chosen for the process. Such olefin-producing substances include alcohols, ethers, and esters capable of undergoing dehydration or splitting to form oleflnlc hydrocarbons containing at least 2 carbon atoms per molecule which may be considered to be present in the reaction mixture even though possibly only as transient intermediate unsaturates which react further with the saturated hydrocarbons to produce desired reaction products.

Oleflnic hydrocarbons and the above mentioned olefin-producing.substances are herein referred to as olefin-acting compounds. Alkyl halides are also olefin-acting compounds and may be considered as esters of halogen acids.-

Organic compounds other than hydrocarbons which may be utilized in the process of the present invention include such alkylatable compounds as the phenols and heterocyclic compounds such as indole. Examples of isomerizable organic compounds are halogenated paraflins containing at least two and preferably three carbon atoms and certain halogenated aromatics, such as ortho chloroethyl benzene. I I m I have found that catalysts useful in promoting the formation of more-highly branched hy drocarbons from less highly branched hydrocar- 1 lions may be made by interactin boric acid with a metal halide of the Friedel-Crafts type under suchconditions that limited amounts of hydrogen halide are evolved, which amounts generally arefrom about 0.5 to about 2.0 molecular equivalents based upon the metal halide. It is apparent that since there are a number of Friedel-Crafts type metal halides which may be interacted, a considerable number of alternative catalysts may be made although such catalysts will not necessarily be equivalent in their action in any par;

ticular hydrocarbon conversion reaction to produce more-branched chain hydrocarbons.

. Friedel-Crafts type metal halides which may be reacted with boric acid to form catalysts useml in the present process include aluminum chloride, aluminum bromide, zinc chloride, zirconium chloride, ferric chloride, antimony chloride, bismuth chloride, and others. Substantially anhydrous'aluminum chloride is the Friedel-Crafts type catalyst usually employed in hydrocarbon conversion reactions of the types mentioned herein. However, disadvantages accompany its use in some instances on account of its high degree of activity. Thus it has a tendency to form undesirable complexes with unsaturated and aromatic hydrocarbons. However, by reacting proportioned mixtures of an aluminum halide, such as alumlnum chloride, and boric acid in accordance with the present invention, catalysts of modified activities are obtained which may be utilized for promoting the formation of more highly branched chain hydrocarbons as herein set forth. These catalysts do not form substantial amounts. of

' complexes with unsaturated and aromatic hydrocarbons and. accordingly, they may be used in continuous processes over long periods of time with relatively little contamination by suchcomplexes that in many instances the catalyst life is considerably longer than the life of the corresponding aluminum halide in similar types of hydrocarbon conversion reactions. An additional ad'- vantage of these catalysts is that their solubility in the products of the reaction is considerably effected between the organic compound and the catalyst.

In continuous operations the granular catalyst, either alone or on carriers, may be placed in reaction chambers and preheated mixtures of the organic compounds alon with hydrogen halide may be passed through'the catalyst bed. The

products from such a treatment may be continuously fractionated to separate the hydrogen halide from the organic compounds.

The reactions described herein are carried out at temperatures of'from about 20 to about 150" C.-and under a pressure of from substantially at-- mospheric to approximately 100 atmospheres. In

the hydrocarbon mixtures subjected to alkylation' it is preferable to have present from about 2 to about molecular proportions of the alkylatabie hydrocarbon per one molecular proportion of oleflnic hydrocarbon.

The following examples are given to illustrate the method of preparing the catalyst and the} character of results obtained by the use of the present process although'the data presented are not introduced with the intention of unduly re-'\ stricting the generally broad scope of the invention.

EXAMPLE I A catalyst was prepared as follows: 20.64 g.

(54; mole) of C. P. boric acid and 133.3 g. (1 mole) of anhydrous aluminum chloride were intimately mixed. by rotating in aball mill for 20 hours.

less than that of, metal halides, such as aluminum chloride and aluminum bromide, and thus the.

usual step of recovering dissolved catalyst from the reaction products can be eliminated.

The bulk of this mixture was transferred to glass liner and heated for two hours at 200 C. and then for two more hours at 250 C. in a rotating bomb. Th product was recovered in two parts as follows:

- Grams In lower part of liner 95.3 In upper part of liner 2.0

The material in the upper part of the'liner a'ppeared to be sublimed aluminum chloride and was discarded. The material in the lower part 0! the liner was a hard, brittle. granular, yellowgray solid which was designated as the catalyst. It was noted that hydrogen chloride was evolved during the mixing in the ball mill and during the heating in the bomb.

EXAMPLEII Part of the catalyst prepared as described in Example I was used to isomerize n-pentane in an Ipatiei! rotating autoclave. The charge stock consisted of volume per cent of C. P. normal pentane and 10 volume Per cent of cyclohexane. The operating conditions and results'are shown in the following table.

Tan 1 Ismneflzatlon of normal pentanc Operating conditions:

Temp. --C. Time Lrs 4 Max. press. .lrg./cm. 80

The results show that over 50% or the normal pentane was converted to isopcntane.

nxauennm A portion or the catalyst prepared as described in Example I' was used in the batch alkylation or benzene with propylene with the rollowing resulta v I run: 2' c Alkylation of benzene with i miene Operating conditions:

Temp. 1 0-- 100 Time .hours 4 Charged. srams:

Catalyst 17.8 80 H01 10.0 Benzene 156.0 Propylene r 15.4 Recovered hydrocarbons: Non-condensable gas cc 1140 Liquid "grams" 170 Distillation of liquid product Cuts 522: 1 cc. Grams. an"

no a7 1.4 1.4 a4 1.1 as as 8.1 7.0 28 22 1.4012 2.7 as 1. 401s 2.9 1.4m

Cuts 8- through 12 represent monopropylated benzene. These cuts were water white and saturated to potassium permanganate.

EXAMPLE IV Propylene was polymerized in a batch experi-, ment using still another portion or the catalyst prepared as described in Example I. The operation conditions and results are shown in Table 3.

Duuuotm of liqutd prcduct I 4 Weight B u out Ra get C. 311231123; "D?

' Charge 10 L421 23 1.4474 a 1.4008 s Cuts l and 2 decolorized potassium permanganate immediately, which shows that they were unsaturated. The residue was very viscous and was unsaturated to bromine in carbon tetrachloride.

I claim as my invention: 1. A process for producing hydrocarbons or branched carbon structure which comprises subjecting a reactive hydrocarbon under conversion conditions to the action of a catalyst prepared by reacting boric 'acid and a metal halide or they Friedel-Craits typel with the evolution of hydrogen halide. T

2. A process for producing hydrocarbons of branched carbon structure which comprises sub- Jecting a reactive hydrocarbon under conversion conditions to the action of a catalyst'prepared by reacting boric acid and aluminum chloride with i the evolution'ot hydrogen chloride.

3.'A process for producingalkylated aromatic hydrocarbons which comprises contacting an aromatic and an olefin under alkylating conditions with a catalyst prepared by reacting boric acid and aluminum chloride with the evolution or hydrogen chloride.

4. The process of claim 3 further characterized in that said process is carried out at a temperature of from about -20 C. to about C.

5. A process for producing alkylated benzene which comprises contacting about 2 to about 20 molecular proportions of benzene and one mo- I lecular proportion of an olefin at a. temperature 0! from about -20 to about 150 C. with a catalyst prepared by reacting boric acid and aluminum chloride with the evolution of hydrogen chloride.

6. A processior the isomerization of isomerizable hydrocarbons which comprises subjecting said hydrocarbon to the action of a catalyst prepared by reacting boric acid and aluminum chloride with the evolution of hydrogen chloride. 7. A process for the isomerization of straight chain and mildly branched paraflins to more highly branched paraflins which comprises sub- Jecting said paraflln at a temperature of. from about 20 to about 150 C. to the action or a catalyst prepared by reacting boric acid and aluminum chloride with gen chloride.

8. A process for theisomerization oi' n-butane to isobutanewhich comprises subjecting n-butane at a temperature of from about -20 to about 150 C. to the action of a catalyst'prepared by reacting boric acid and aluminum chloride with the evolution or hydrogen chloride.

the evolution of hydro- 9. A process for the polymerization of olefinic hydrocarbons which comprises subjecting s aid olefin to polymerization in the presence of a catalyst prepared by reacting boric acid and aluminum chloride with the evolution ol hydrogen chloride. 10. A process for the polymerization of normally gaseous oleilnic hydrocarbons which comprises subjecting said hydrocarbons to polymerination at a temperature or from about 20 to amtm I about 150 C. in the presence or a catalyst pre- 8 and aluminum chloride with the evolution of hydrogen chloride.

' A JULIAN M. MAVI'I'Y.

REFERENCES CITED The following references are of record in the tile of this patent:

UNITED STATES PATENTS m Number Name Date 2,109,340 Nieuwland et al. Feb. 22, 1938 2,358,011 v Ipatiei! et al Sept. 12. 1944