US3190835A - Metal deactivators - Google Patents

Description

United States Patent 3,190,835 METAL DEACTIVATORS Wilhelm C. Brezesinska Smithuysen, Daniel van Velzen, Jacob C. Caron, and Wim de Bruine, all of Amsterdam, Netherlands, assignors to Shell Oil Company, New York, N.Y., a corporation of Delaware N0 Drawing. Filed June 28, 1961, Ser. No. 120,178 Claims priority, application Netherlands, July 29, 1960, 254,361 7 Claims. (Cl. 252-47) This invention relates to improved hydrocarbon oils and particularly to gasoline, kerosene and transformer oil compositions having improved oxidation stability.

It is known that certain hydrocarbon oils such as motor fuels boiling within the gasoline boiling range, i.e., gasoline produced from the cracking of petroleum, have an undesirable tendency to undergo deterioration on storage, with loss in such valuable properties as light color, low gum content and antiknock values. Moreover, blends of these unstable gasoline compositions with more stable gasolines, such as straight run gasoline, frequently also show a tendency to deteriorate upon storage. This oxidative deterioration of hydrocarbon oils is considerably ac celerated by traces of polyvalent metals nearly always present in these materials. Copper in particular has a great accelerating effect on oxidative deterioration of most hydrocarbon oils during storage. As a result, the acid number and sludge content of transformer oil, for example, may increase to such an extent that the oil has to be renewed, whereas in gasoline the gummy products formed by this catalyzed deterioration often later cause fouling of engine carburetor and fuel lines.

It is known that the catalytic oxidative effect of certain polyvalent metals in hydrocarbon oils can be neutralized by the addition of certain complexing compounds to these materials. Most of the complexing compounds used today are derivatives of salicyclaldimine, i.e., having the general structural formula:

In addition, compounds in which two of these groupings are bound by, an ethylene bridge are often used. The corresponding ketimine derivatives as well as derivatives from amino-phenol and from anthranilic acid are also employed.

The above types of complexing compounds, however, all have the disadvantage in that they contain a functional group capable of reacting with alkali also present in the hydrocarbon oil. The resultant alkali-metal deactivator salts, will not form complexes with the catalytically active polyvalent metals. In addition the alkalimetal salts formed are water-soluble, therefore during storage, they accumulate in the separating aqueous phase and are ultimately lost.

It is an object of this invention to provide hydrocarbon oil compositions with improved stability. It is a further object of the invention to increase the oxidative stability of certain gasoline compositions without affecting the detonation resistance of the gasoline and without increasing either the toxicity of the fuel composition or its tendency to lay down combustion chamber deposits. A still further object of the invention is to provide improved hydrocarbon oil compositions containing metal deactivator compounds which are effective in the presence of alkali. The attainment of these and other objects will be apparent from the detailed description of the invention which is a hydrocarbon oil composition containing small but critical amounts of certain complexing agents, capable of forming complexes with polyvalent metals in the presence 31,190,835 Patented June 22, 1965 ice of alkali, and which, in the presence of an alkaline or non-alkaline aqueous phase will not pass into that phase.

X Bil Wherein each R can be a hydrogen atom, an alkyl radical, an aryl radical, an aralkyl radical or an alkaryl radical or the two Rs together with the wherein each R can be an imino radical or an alkylene radical containing from 1 to 3 carbon atoms and each X is a nitrogen-containing heterocyclic radical containing from 3 to 9 carbon atoms bonded to R in the 2-position such as Z-thiazolyl, 2-pyridyl, 2-quinolyl and 2-isopyrrolyl radicals.

In an also preferred embodiment of the invention, disubstituted diphenyl pyrroline compounds are used as the complexing agent. These materials have the structural formula:

R-X Cairo-i;

\NH 0,13 -o ,ii-X

Wherein each R can be an amino radical or an alkylene radical containing from 1 to 3 carbon atoms and each X is a nitrogen-containi-ng heterocyclic radical containing from 3 to 9 carbon atoms bonded to R in the 2-position such as Z-thiazoly-l, 2-pyridyl, 2-quinolyl, and 2-isopyrrolyl radicals.

It has now been discovered that the addition of the class of compounds of Formula I to hydrocarbon oils such as gasoline, kerosene, gas :oil and transformer oil, unexpectedly improves the stability of these hydrocarbon oils even in the presence of alkali. For example, diasubstituted isoindol-ine compounds are capable of complexing various polyvalent metals which act as oxidative catalysts even when these metals are in hydrocarbon oils containing 1-(2'-quino1y1imin0) 3-(2'-isopyrr0lylimin0) isoindoline, l.e.,

and 2,5-di(2 pyridy1imin0)3,4-diphenyl-pyrroline, i.e.,

and the certain materials which can be more readily de- 39 fined by setting forth their structural formula, i.e.

CHaCHg alkali. This result is particularly significant since conventional metal deactivators added to hydrocarbon oils in the presence of alkali fail to exhibit these complexing properties and thus fail to impart improved oxidative stability to the hydrocarbon oil compositions.

Specific examples of the complexing compounds of the invention are:

1,3-di(2-pyridylimino)-isoindoline, i.e.;

1,3-di(2-thiazolyli1nino)-isoindo1ine, i.e.,

l. 063 orn The various 1,3 substituents of the isoindoline compounds and 2,5 substituents of the pyrroline compounds above are preferably limited to nitrogen containing heterocyclic radicals which are bound to the isoindoline or pyrroline compound in the 2-position. 7

It was discovered that the complexing agents of the invention such as the di-substituted isoindoline compounds of the invention improve the oxidative stability of hydrocarbon compositions containing alkali and certain polyvalent metal, that is when the materials of Formula I are added to gasoline compositions in concentrations sufficient to deactivate the oxidation catalyzing metals contained therein, these metal deactivating compounds did not become water soluble upon extraction of the gasoline with alkali, whereas, conventional deactivators became water soluble and were readily extracted from gasoline with water and/or aqueous sodium hydroxide, when similarly treated.

For example 1,3-di(2'-pyridylimino)-isoindoline, 2,5- di-(2-pyridylimino)3,4-diphenylpyrroline and 1,3-di(2'- thiazolylimino)-isoindoline were dissolved in a gasoline. 1,3-di(2-pyridylimino)-isoindoline was prepared by the method desired by I. A. Elvidge and R. P. Linstead, I.

\ Chem. Soc., 1952, p. 5000 et seq., whereas the two other examples, 2,-B-di(2'-pyridylimino)3,4-diphenyl-pyrroline and 1,3-di(2-thiazolylimino)-isoindoline, were prepared as follows:

2,5-di(2'-pyridylimin0)3,4-diphenylpyrr0line.-A Il'liX- ture of 100 parts by weight of 1,2-diphenyl-1,2-dicyanoethene and 90 parts by weight of 2-aminopyridine were heated for 3 hours at 220 C. Evolution of ammonia occurred. The melted mass was dissolved in 4000 parts by weight of boiling n-butanol. The solution was cooled down to 12 C. and the crystallized product filtered and washed with pentane. The yield amounted to 90 parts by Weight of 2,5-di(2-pyridylirnino)3,4-diphenyl-pyrroline in the form of black-green crystals.

Analysis.-Carbon 77.7% w., hydrogen 5.1% w., nitrogen 17.0% w. Calculated for C H N carbon 77.8% w., hydrogen 4.7% W., nitrogen 17.4% w.

1,3 di(2' thiazolylimino) isind0line.20 parts by weight of Z-amino-thiazole and 14.5 parts by weight of 1,3-di-imino-isoindoline were dissolved in 400 parts by weight of isobutanol. The solution was boiled under reflux for 8 hours. Evolution of ammonia took place. After cooling 20 parts by weight of green-colored crystals was obtained. After crystallizing in 6400 parts by weight of isobutanol the yield was 18 parts by weight of 1,3-di(2- thiazolylimino)-isoindoline in the form of green-yellow needles. The melting point was 277 C.

Analysis.Nitrogen content 22.6% w. Calculated for C H N S nitrogen content 22.5% W.

In the following l,3-di(2'-pyridylimino)-isoindoline is indicated as Compound A, 2,5-di(2'-pyridylimino)3,4-diphesnyl-pyrroline as Compound B and l,3-di(2-thiazolylimino) isoindoline as Compound C. Compound A, Compound B and Compound C each were dissolved in a catalytically cracked gasoline having a boiling range of from about 40 to 200 C., in a concentration of 2.5 p.p.m., 5 p.p.rn. and 6.7 p.p.m., respectively. The resultant gasoline compositions were extracted with water and an aqueous solution of sodium hydroxide. A similar exraction was also carriedout with a catalytically cracked gasoline containing 2.5 p.p.m. of disalicylal-ethylene diamine, a conventional metal deactivator. The result of these extractions are set forth below in Table I.

TABLE I Percent of Percent compound of di- Extracting agent extracted salicylalethylene diamine. A B O extracted 10 by vol. of water having a pH of 6.0. 0 10% by vol. of a 0.1 by wt. caustic soda solution 0 10 by vol. of a 1.0 wt. caustic soda solu on 0 0 0 100 2 by vol. of a 5 wt. caustic soda solution 0 100 1 by vol. of a 10 by wt. caustic soda nlntinn 0 100 1 by vol. of a 30 by wt. caustic soda solution 0 0 The oxidative stability of a catalytically cracked gaso line having a boiling range of from about 40 C. to about 200 C. and containing copper in catalytic concentrations, i.e., containing a copper coil strip equal to about 1 sq. cm. of copper per 20 ml. of gasoline, was tested with and without the addition of 10 ppm. of 1,3-di(2- pyridylimino)-isoindoline, by storing the gasoline composition, in the atmosphere in an open glass vessel.

The induction period of the gasoline in fresh conditions and after it had been stored for one week was determined by ASTM Method D525. The copper content of It is evident from the data set forth above that the copper chelate formed by the 1,3-di(2-pyridylimino)- isoindoline is not catalytically active, so that there is no catalyzed oxidative deterioration of the gasoline.

The induction period of a catalytically cracked gasoline having a boiling range of from about 40 to about C. was determined by ASTM Method D525. Copper napththenate was then dissolved in the gasoline and the induction period determined. The induction period of similar gasolines containing Compounds A, B and C and copper naphthenate were also determined. The results are set forth in Table III below.

A catalytically cracked gasoline having a boiling range of from about 40 to about 190 C. was treated with 10% by volume of a 1% by weight caustic soda solution. Cop per naphthenate was then dissolved in the treated gasoline. A similar gasoline was treated with caustic soda in the same way and copper napthenate and Compound A were then dissolved in the treated gasoline. 'Similar gasolines containing the Compounds A, Band C were treated with caustic soda as'described above and copper naphthenate was then dissolved in the treated gasoline. The induction periods of the gasolines were determined by ASTM Method D525. The results are set forth in Table IV.

The oxidative stability of caustic-treated similar gasolines containing disalicylal-ethylene diamine was also de- 5" termined using ASTM Method D525. These results are set forth in Table V.

TABLE III Concentration, Concentrap.p.m. of tion of copper Induction compound naphthenate period,

expressed as minutes p.p.m. copper A B O Catalytically cracked TABLE IV Induction period in minutes Gasoline treated with caustic soda solution 300 Gasoline treated with caustic soda solution and then 0.5 p.p.m. of copper as copper naphthenate added Gasoline treated with caustic soda solution and then 0.5 p.p.m. of copper as copper naphthenate and 6 p.p.m. of Compound A added Gasoline containing 6 p.p.m. of Compound A treated caustic soda and then 0.5 p.p.m. of copper as copper naphthenate added Gasoline containing 5 p.p.m. of Compound B treated with caustic soda and then'0.5 p.p.m. of copper as copper naphthenate added Gasoline containing 6.7 p.p.m. of Compound C treated with caustic soda and then 0.5 p.p.m. of copper as copper naphthenate added 195 TABLE V Induction period in minutes Gasoline containing 0.5 p.p.m. copper as copper naphthenate and 3 p.p.m. of disalicylal-ethylene diamine 280 Gasoline containing 3 p.p.m. of disalicylal-ethylene diamine 320 Gasoline containing 3 p.p.m. of disalicylal-ethylene diamine treated with caustic soda and then 0.5 p.p.m. of copper naphthenate added 120 It is readily apparent from the results set forth in Table III that the addition of copper naphthenate has an adverse effect on the oxidative stability of the gasoline tested and that metal deactivators of Formula I, i.e., 1,3- di(2'-pyridylimino)-isoindoline, 2,5-di(2 pyridylimino) 3,4-diphenyl-pyrroline and 1,3-di(2-thiazoly1in1ino)-isoindoline are capable of counteracting this adverse effect. It can also be seen from Table III as well as from Table II, that even in the absence of copper naphthenate or copper, the stability of gasoline is further improved by the addition of Formula I type compounds. The data set forth in Table IV and in Table V show that the Formula I type compounds are resistant to treatment with a caustic soda solution, whereas conventional metal deactivators, such as disalicylal ethylenediamine, are not.

The stability of a mineral oil fraction containing 1,3- di(2' pyridylimino) isoindoline was examined in the S.E.V. test (Publication No. 124, Regeln fiir Isolieriil, by the Schweizeriseher Elektrotechnischer Verein, January 1, 1936). The mineral oil fraction was a naphthenic spindle oil extracted with sulphur dioxide and having a viscosity of approximately 80 SUS at 100 F. This oil was tested as such and after the addition of 0.01% and 0.02% by weight respectively of 1,3-di(2'-pyridylimino)- isoindoline and disalicylal ethylenediamine. The oil was heated to 110 C. in a copper beaker for seven days, a

copper bar provided with a cotton thread winding being present in the oil. The results of these tests are set forth in Table VI below.

In addition to being effective in improving the oxidative stability of hydrocarbon oils such as gasoline, kerosene, gas oil, transformer oil and crankcase lubricating oils, the metal deaetivators of Formula I can also be used .in specialty products such as mineral spirits, paint solvents and the like. Particularly beneficial results are generally achieved in the case of liquid hydrocarbon products and especially hydrocarbon distillates.

The improvement in the oxidative stability of various hydrocarbons by the use of the compounds of Formula I may be obtained over a wide range of concentrations, that is, the concentration of these materials may be as low as 0.1 p.p.m. and as high as 150 p.p.m. depending upon the particular material in which it is incorporated, the severity of the conditions to which the hydrocarbon is to be subjected and the length of time the hydrocarbon base must be protected against deterioration. For example, in most gasolines, jet fuels and other hydrocarbon distillates, the lower concentrations are ordinarily sufficient, that is, up to about 15 p.p.m. and particularly about 1 to about 10 p.p.m. are preferred.

In a preferred embodiment of the invention the metal deactivator of Formula I is'used in gasoline fuels. The stabilized gasoline fuel compositions of this invention include thermally or catalytically cracked, thermally or catalytically reformed gasolines or products of sulphuric acid or hydrochloric acid alkylation of lower molecular weight olefins and isoparaffins, e.g., of butylene and isobutane and mixtures thereof. Automotive gasoline fuel compositions having a boiling range from about the boiling points of C to C hydrocarbons to about 450 F., are suitable as the hydrocarbon base of the invention. These fuels will preferably have an ASTM Method D-86 distillation range of from about to F. to about 357 to 425 F.

In addition to the metal deactivator, the stabilized gasoline fuel compositions of the invention will preferably contain an octane-improving amount of an organo-lead antiknock agent, i.e., a lead antidetonant, such as tetralower-alkyl lead compound, for example tetraethyllead, tetramethyllead, diethyl .dimethyl .lead, ethyl trimethyl lead, methyl triethyl lead and mixtures thereof. The concentration of the lead antiknock agent is generally at least 0.5 cc. per gallon and up to 6 cc. per gallon, more especially at least 1 cc. per gallon and no more than 4 cc. per gallon. When a lead antiknock agent is used a halohydrocarbon scavenger such as ethylene dibromide or a mixture of ethylene dibromide and ethylene dichloride will usually be addedin conjunction therewith, especially in an amount-of from about 1.0 to about 1.5 or 1.6 theories, 1.0 theory being the amount necessary to provide two atoms of halogen per atom of lead in the lead antiknock agent present. The gasoline compositions of the invention can also contain other antiknock agents such as iron-pentacarbonyl, dieyclopentadienyl iron, xylindene, N-methylaniline, and the organo-manganese compounds such as described in Brown et al., US. 2,818,417, December 31, 1957, especially methylcyclopentadienyl manganese tricarbonyl, or bis(cyclopentadienyl) manganese.

Other additives which may be added to the gasoline compositions of the invention include the various antiicing agents such as the mono-N-alkyl substituted propylenediamines; combustion chamber deposit modifiers such as esters of boric acid, for example, isopropyl 2- methyl-2,4-pentanediol borate, 2-methyl-2,4-pentanediol monoacid borate, bis(1,1,3-trimethyl trimethyleneoxy) boric acid, and the like; corrosion inhibitors such as polymerized linoleic acids and N,C-disubstituted imidazolines; metal deactivators such as N,N-disalicylal-1,2- propanediamine; and dyes, silicone oils, and the like.

In addition to the compositions described above, a suitable example of a gasoline composition for use of the invention is set forth below:

Catalytic reformate percent v 70 Straight run gasoline percent v 30 1,3-di(2-isopyrrolylimino)-isoindoline p.p.m Tetraethyllead cc./ gal- 2.8 Ethylene dibromide theory 0.5 Ethylene dichloride do 1.0 Tricresyl phosphate do 0.3

The lubricating oils to which the compounds of Formula I are added are preferably mineral oils. They can be parafiin base, naphthene base or mixed paratfin-naphthene base distillate or residual oils. Lubricating oils having an SUS viscosity of 100 F. between about 50 and 1,000 may be used. These lubricating oils will usually contain other additives such as detergents and dispersants. A preferred lubricating oil for use in the invention is a non-ash forming mineral oil within the SAE -30W range.

The following are illustrative examples of compositions suitable for use according to the invention.

Example I Transformer oil containing p.p.m. of 1,3-di(2'- pyridylethylene) -isoind oline.

Example ll Kerosene containing p.p.m. of 1,3-di(2'-quinolyln-propylene -isoindoline.

Example III Gasoline containing 5 p.p.m. of 1-(2'-thiazolylimino)- 3- (2-pyridy1imino -iso-indoline.

Example IV Gasoline containing 1 p.p.m. of 1,3-di(2'-pyridylimino)- isoindoline.

Example V Gas oil containing 50 p.p.m. of 1,3-di(2-isopyrrolylimino) -isoindoline.

Example VI Mineral lube oil having a viscosity of 320 SUS at 100 F. containing 5 ppm. of 1-(2'-isopyrrolylimino)-3-(2- quinolyl-methylene) -isoindoline.

Example VII Kerosene containing 20 p.p.m. of a complexing agent having the structural formula:

Inc-ii mo U 10 Example VIII A gasoline composition contain 10 p.p.m. of a complexing agent having the structural formula:

Example IX A lubricating oil containing 5 p.p.m. of a complexing agent having the structural formula:

l: l l 1 l l A 0g OH OH Example X A gasoline composition containing 10 p;p.m. of a complexing agent of the formula:

wherein R is selected from the group consisting of hydrogen, alkyl, aryl, aralkyl and alkaryl, with the proviso that the carbon atoms within the R groups which are in the beta position relative to N can be members of a nonacetylenically-unsaturated S-membered hetenocyclic ring in which N is the hetero atom, R is selected from the '1 1 group consisting of imino and alkylene having from 1 to 3 carbon atoms, and X is a heterocyclic nitrogencontaining radical, bonded to R in the 2-position, selected from! the group consisting of Z-thiazolyl, 2-pyridyl, 2- quinolyl, and 2-isopyrroly1.

2. A composition according to claim 1 wherein the hydrocarbon i1 is a gasoline fuel.

3. A composition according to claim 1 wherein the hydrocarbon oil is kerosene.

4. A composition according to claim 1 wherein the hy- 10 drocarbon oil is a crankcase lubricating oil having an SUS viscosity at 100 F. of between 50 and 1000.

5. A liquid hydrocarbon oil containing 0.1-150 p.p.m. by weight of 1,3-di(2-thiazolylimino)-isoindolinc.

6. A liquid hydrocarbon oil containing 0.1150 p.p.m. 15 by weight of 1,3-di(2'-pyridylimino)-isoindo1ine.

312 v '7. A liquid hydrocarbon oil containing 0.15O p.p.m. by weight of 2,5-di(2-pyridylimino) 3,4-diphenyl-pyrroline.

References Cited by the Examiner UNITED STATES PATENTS 2,492,048 12/49 Klabunde 252 401XR 2,595,140 4/52 Heinrich 252-50 2,787,551 4/57 Bell et a1. 44-63 XR 2,864,676 12/58 Thompson 4463 DANIEL E. WYMAN, Primary Examiner.

JULIUS GREENWALD, Examiner.

Claims (1)

1. A LIQUID HYDROCARBON OIL, NORMALLY CONTAINING TRACE AMOUNTS OF ALKALI AND POLYVALENT OXIDATIVE CATALYZING METALS, HAVING IMPROVED OXIDATIVE STABILITY CONTAINING 0-1-150 P.P.M. BY WEIGHT OF A COMPLEXING AGENT CAPABLE OF FORMING COMPLEXES WITH POLYVALENT METALS IN THE PRESENCE OF ALKALI HAVING THE STRUCTURAL FORMULA