US2098046A - Treatment of hydrocarbons - Google Patents

Description

Patented Nov. 2, 1937 UNITED STATES PATENT OFFICE TREATMENT OF HYDROCARBONS Vladimir Ipatieif and Vasili Komarewsky, Chicago, 111., assignors to Universal Oil Products Company, Chicago, 111., a corporation of Delaware No Drawing. Application August 10', 1935, Serial No. 36,560

4 Claims.

This invention relates to the treatment of saturated hydrocarbons such as parafllns and naphthenes representing the groups of chain and cyclic hydrocarbons respectively and, in a more 5 specific sense, is concerned with a process involving the interaction of parafflns and naphthenes in the presence of selected catalysts and under properly chosen conditions of temperature and pressure to form mixed hydrocarbon deriva- 16 tives.

Hydrocarbons of the character involved in the process of the present invention are the less reactive of the hydrocarbon classes in contrast to the more reactive oleflns and aromatics. -In the II case of the paraflins, represented by the general formula CnH2n+2, they show substantially no reactivity with even strong acids like sulfuric unless the temperature is raised to a point where the oxidizing properties of the acid come into play.

20 The cyclic naphthene hydrocarbons having the general formula CnHZn also require oxidizing temperatures for interaction with sulfuric acid though these temperatures may be somewhat lower than those corresponding to paraffin hydro- 26 carbons with the same number of carbon atoms.

' Both paraflin and naphthene hydrocarbons exto paraflins may be somewhat higher in the latter case. Toward each other these two groups are substantially unreactive in the absence of catalysts below cracking temperatures and it is with a catalytic process which enables the interaction of these two groups at relatively low temperatures that the process of the present invention is concerned.

In one specific embodiment the invention comprises reacting paraflln hydrocarbons with naphthenic hydrocarbons in the presence of phosphoric acid at elevated temperatures and pressures to produce mixed derivatives.

According to the present invention any naphthene may be reacted with any paraflin, any single naphthene may be reacted with any mixture of parafllns or any single paraflln may be reacted with any mixture of naphthenes while using a phosphoric acid as a catalyst. It is preferable to use as catalysts the acids of phosphorous in which this element has a valence of 5, and for purposes of reference the names, formulas and common properties of the ortho and pyrophosphoric acids which are the most serviceable in the present instance are given below.

Name M. P. 0. Dec. 0.

Orthophosphorlo HaP0|-- P10031810-- 38.6 Loses )5 H10 Pyrophosphoric HIPl 1- I:0a.2Hi0-. 61 at 213 ist in hizh percentages in the relatively low boil- 35 ing fractions of petroleums of either a paraflinic or a mixed 'base origin, and it may even be said that they preponderate in the lower distillation products of petroleums of a distinctly asphaltlc character even though the ratio of naphthenes Compound pentane. ethyl diethyl ethyl For further purposes of reference and with no intent of unduly limiting the scope of the invention the following tables are introduced to indicate some of the compounds of both the paraffin and naphthene series of hydrocarbons which may be caused to interact.

Formula Boll Melt point" point I M in Compound Formula 33. gh

(n-Thu Z3 "6- 2 giggfl m x n! 261 5 5 Pentadeune. Gun gm 5 Hexsdecane C fi 287. 5 +18 Heptadecane (inn-r 303 +22- 6 OctadecaneuHu 817 I28 Nonnrloonnn on; m a Eimunmr gag-s fig I l lg Gun m m 1 D l mm- 310 +700 Pentm can m +741 Dimyricyl (ll-Hm This and following down to at 700 m. in. pressure, or under.

' This and following to end oi table at or under 16 m. in. pressure.

Naphthenc hydrocarbons Name 5 5- B. P. 'o.

0 elo-hexnn hcxahydro-bcnzol. 0. 7788 81 m othyl-cgc -hexane, hcxahydro-tolucl. 0. 7097 1,1-dimct yl-cyclc-hexane -;-..--L 0. 7804' no 1,2-dimethyl cyclo-hexane, hexahydroon o 0. 7783 1,3-dimethyl-cyclo-hexane, hexahydro' m-xy 0.7736 121 1, idimcthyl-cyclo-hexane, hcxahydrop-xylol 0. 7090 120 Ethyl-cyclo-hoxanc 0. 7772 l,2-methyl-ethyl-cyclo-hcxane.. 0. 784 151 n-Propyl-cyclo-hexanc 0 7865 156 1,3,6-trimethyi-cyclo-hexano, hex hydro-mexitylcne 0. 7867 138 1,3,4-trimethyl cyclo -hexnnc, hexahydroudo-cumol 0. 7807 143 1,3,5-dimethyl-ethyl-cyclo-hex.ene. 0. 7929 169 1,4-methyl slo propyl cyclo hexane,

hexahydro-cy 167 Owing to the fact that there are paraflln hydrocarbons which are normally gaseous, liquid and solid and also naphthene hydrocarbons which exist in the same three phases, it is evident that the details of procedure when carrying out the process are capable of considerable modification, when it is alsoconsidered that varying temperatures and pressures may be used depending upon the reactivity of the various compounds, the proportions in which they are used and the character of the results desired.

In a simple method of carrying out the process, liquid paraillns and liquid naphthenes are mixed and contacted with orthophosphoric acid of approximately 90% concentration in exteriorly heated rotating bombs. The temperature necessary for effecting interaction will vary with the proportions and the molecular Weight of the interacting paraflins and naphthenes respectively so that only general ranges can be given which are approximately 700 to 900 F. The pressures generated will again depend upon the type and character of the interacting constituents and the proportions in which they are employed, though it is common observation that the pressure may be atmospheric or may rise to as high as 100 atmospheres or higher at temperatures in the neighborhood of 800 F. due partly to the evolution of fixed gases resulting from the decomposition of both groups of hydrocarbons.

Continuous operations may be conducted in the case of liquid parafllns and naphthenes by pumping them along with phosphoric acid through tubular heating elements in which they are brought up to the proper reaction temperature and then discharging the reaction products into settling chrmbers in which the phosphoric acid is separated as a lower layer while the lower boiling hydrocarbon products are released as vapor and fractionated under reduced pressure and any unvaporized hydrocarbon products are drawn. oil with the phosphoric acid.

In cases involving the interaction of gaseous paramns and liquid naphthenes, several alternative modes of operation will suggest themselves to those familiar with these typu of commercial operation. For example, in batch operation paraiflnic gases may be pumped continuously into heated mixtures of naphthenes and phosphoric acid until the desired degree of reaction has taken. place or gases 'and liquids may be vaporized and passed upwardly countercurrent to descending streams of phosphoric acid in towers containing inert baiiling or spaced filling material. The process is not limited to the particular type of mechanical arrangement of apparatus which may be employed to effect the desired reactions.

Observation 01 a considerable number of reactions typical of the present process indicates that what may be termed a destructive alkylation occurs. ihere is a variable amount of decomposition of each of the reacting compounds, both paraiiinic and naphthenic with the formation of transient radicals which results to form mixed derivatives of the general character of alkylated naphthenes. This necessarily involves some loss of hydrogen and there are also formed some low boiling parafflnic gases such as methane and ethane owing to the lack of 100% efllciency in the reactions. The process is of especial value in increasing the antiknock value of naphthenic distillates by the use of low boiling paraflln hydrocarbons from methane to hexane, such as are normally present in natural and refinery gases.

The following example is given to indicate the character of the results obtainable by the use of the present process though it is not intended for the purpose of correspondingly limiting the scope of the invention.

50 parts by weight of cyclohexane and 50 parts by weight of normal hexane were heated in a rotating pressure vessel with 15 parts by weight of 100% orthophosphoric acid at 842 F. for a. period of 12 hours.

After cooling and release of the residual gas pressure, the bomb contents were found to consist of a lower layer of partly spent phosphoric acid (chiefly contaminated by dissolved esters of the acid) and an upper hydrocarbon layer which upon fractionation showed the presence of 20 parts by weight of alkylated aromatic hydrocar- 7 bons boiling within the range of 230-340 F. By resubjecting the unaflected hexane and cyclohexane to the same treatment after the removal of the alkylated reaction products it was found possible to increase the yield of alkylated aromatic and naphthenic reaction products to approximately 60% of the original reacting constituents. These products were directly utilizable for blending material for increasing the antiknock value of gasoline.

The above specification and numerical data. have been given to indicate the general character of the invention and to illustrate the results obtainable by its use although neither section'is intended to be unduly limiting.

We claim as our invention:

1. A process for producing alkylated hydrocarbons which comprises reacting a paraffln and a.

20 naphthenic hydrocarbon at destructive alkylation temperature of from about 700 F. to 900 F. and in the presence of orthophosphoric acid.

2. A process for producing alkylated hydrocarbons whichcomprises reacting a paraflin and a. naphthenic hydrocarbon at destructive alkylation temperature of from about 700 F. to 900 F. and in the presence of pyrophosphoric acid.

3. A process for producing alkylated hydrocarbons which comprises reacting a paraffin and a. naphthenic hydrocarbon at a temperature of from about 700 F. to 900 F. and in the presence of a phosphoric acid.

4. A process for producing alkylated hydrocarbons which comprises reacting a paramn and a naphthenic hydrocarbon at a temperature of from about 700 F. to 900 F. and in the presence of a phosphoric acid in which the phosphorus has a valence of 5.

VLADIMIR IPATEEFF. VASIH KOMAREWSKY.