Patented Oct. 27, 1942 2,300,246 INHIBITOR FOB GASOLINE Joseph A. Chenicek and Chicago, Ill., assignors note Company, Chicago,
Delaware BobertH. Itosenwald, to Universal Oil ProdllL, a corporation of No Drawing. Application October 27, 1939, Serial No. 301,636
Claims- (01.44-45) This invention relates to a method (or stabilizing olefin-containing hydrocarbon oils and more particularly cracked gasoline of petroleum orig against deterioration and loss of valuable properties on storage. Gasolines from other sources may also be treated according to the present invention, as may other hydrocarbon fractions such the polymerization of northe reiorming of naphthas,
as those produced by mally gaseous oleflns, etc.
More particularly method for stabilizing olefin-containing gasoline during storage in respect to valuable properties such as color, antiknock value and low gum content which tend to depreciate because of the action of oxygen upon the oleflns in said gasoline.
The cracking and reforming of petroleum oils to produce additional yields of valuable motor fuel or to improve the antiknock characteristics of straight-run gasolines and naphthas has been practiced to a large extent during recent years. Furthermore, processes have been developed for polymerizing the normally gaseous olefins contained in cracking plant gases to produce substantial yields of high octane number blending fluid. All of the products thus produced, whether by cracking, reforming or polymerization, contain substantial amounts of oleflnic hydrocarbons which tend to form peroxides and gums and to depreciate in antiknock quality, color, odor, etc. when stored in the presence of even minor amounts of oxygen. The use of inhibitors has been practiced to prevent such reactions and many types of compounds have been suggested for this purpose, including aminophenols, fractions of wood tar, polyhydroxyphenols, etc.
In one specific embodiment the present invention comprises a method for treating unstable olefin-containing gasolines to preserve their valuable properties in respect to gum content, color and antlknock properties by adding thereto minor quantities of allnvl ethers of aminophenols oi the general structure:
wherein R is either a hydrogen atom or an alkyl group, and R is an alkyl group.
the invention concerns a The properties desirable in a gasoline gum inhibitor are as follows:
(a) Solubility in the gasoline to a degree in excess of the maximum concentration in which it is likely. to be used.
(1:) High degree of potency so that relatively small concentrations can be used.
(c) Insolubility or relatively low solubility in water or aqueous alkaline 0r acidic solutions with which the gasoline is likely to come in contact.
(d) Either normally liquid or having a high degree of solubility in a non-aqueous, gasolinemiscible solvent thus increasing the ease of handllng and addition to the gasoline.
(e) Nonreactive with tanks, fittings, lines, engine parts, etc., with likely to come in contact.
(f) 01 light color, and ing no objectionable color or odor when added, or during storage.
The inhibitors of the present invention to a large extent fulfill these requirements.
A representative group of the compounds which are useful are given in the example.
The alkom group and the N-substituted alkyl group may contain any suitable alkyl group such as normal, secondary, or tertiary allql groups, and may be either the same or difierent in molecular weight and structure.
The compounds may be prepared by reacting the sodium salt of nitrophenol with an alkyl halide of the desired molecular weight and structure followed by reducing the nitro ether thus formed to the amino ether. The amino ether may then be reacted with an alkyl halide to produce the N-substituted amino ether. Another method oi preparing the compounds is to react the sodium salt of an N-substituted aminophenol with an alkyl halide to produce the N-substituted amino ether.
The followin examples are given to illustrate the usefulness and practicability of the compounds characterizing the invention but should not be construed as limiting it to the exact compounds given therein.
The inhibitor effectiveness 01 the compounds was measuredby means of the oxygen bomb induction period. In this test a sample of gasoline with and without 0.01% by weight of the added imparting or developto the gasoline which the gasoline is curred was measured.
compound was heated a pressure recording desodium hydroxide solution. The
data obtained are shown in Table II.
Tun: II Enect of caustic and water on aminophenul I I ether;
Cu dish gum, mg./100 cc. Induction period, minutes Per ggfi .Inhibitor Water Caustic Water Ciustic Water Caustic min wash wash wash wash wash wash Blank gasoline 00 11a 19 so 70 so Commercial inhibitor A 7 12 80 340 285 105 17 79 Commercial inhibitor B 9 14 300 305 210 0 27 p-Aminophenyl isobutyl ether 49 18 19 360 325 280 9 l8 p-Aminophen lisopropyl ether 25 25 25 305 280 260 7 7 pn-Butyl g-phenyl t-butyl ethe 12 10 350 310 310 ll 4 pn-Butylamino henyl n-butyl ether 21 35 23 310 310 305 0 0 p- Isopropylamino hen lisopropyl ether" 10 17 10 28) 265 240 3 5 p-(Isonmylamino)-p eny t-butylether 8 9 11 315 295 285 4 0 Vice whereby the interval of time between t initiation o! heating the induction period.
TABLE I Inhibitor ratios of various p-alkylaminophenyl ethers Induction N 0. Compound .Minutes Blank gasoline 85 1 p-(n-Bntylamino)-plienyl t-butyl ether. 410 2 p-(laosmylaminoyghenyl t-butyl other. 375 3 p-Aminophonyl iso utyl ether 205 4 p-gn-Butylaminoyphenyl n-butyl ether 18g 5 pn-Butylamino)-phenyl ally] ether 17a 6 p-(Methylamino)-phenyl isobutyl ethcr 170 7 p-Aminophenyl isopropyl ether 165 8 p- Isoamylnmino)- henyl sec-butyl ether 165 9 ppropylamino -phenyl isopropyl other.-. 165 10 ppropylamino henyl t-butyi ether 165 11 pn-Butylaminogenyl isobutyl other.-- 155 12 p-(n-Butylamino -phe nyl sec-butyl ML. 155 13 pn-Butylamino)- henyl isoamyl other-.- 155 14 ppropylsminoyl'iehenyl isobutyl ether 150 15 p-(Isosmylsmino)-p nyl n-bntyl other-.- .150 16 p-Aminophenyl nrogy] other 145 17 ppropylsmino -p enyl sec-butylether 145 18 pn-Butylaminog-pheny ethei ether 145 19 pn-Butylamino -pheny isogropyl ethe 140 20 psoamylamino)- henyl iso utyl ether 140 21 p-(Isopropylsminof-ghenyl isoamyl other 140 22 p-Aminophenyl met yl ether 135 23 p-Aminophenyl n-amyl ether 135 24 psoarnylaminog-phenyl isopropyl ether 135 25 p-(Isoamylamino henyl isoamyl ether. 135 26 p-Aminophenyl et yl ether. 130 27 p-Aminophenyl sec-butyl ether 130 As further evidence 01 the usefulness of the compounds of the present invention, several representative compounds were compared with two commercial inhibitors. Suilicient amounts of the various compounds were added to a gasoline to give an induction period of the same order of figure. The copper. dish gum and induction periods were determined before and after shaking the samples with water and with dilute (1%) resultsindicate that the compounds of this invention are relatively insoluble in water and sodium hydroxide, being superior in this respect to the commercial inhibitors with which they are compared. Translated into terms of commercial practice, these data indicate that the inhibitors when presentin gasoline stored in tanks containing water or alkaline aqueous solutions will not be removed thereby, but will continue to protect the gasoline from the deleterious eifects of oxidation.
We claim as our invention:
1. An inhibitor for cracked ing essentially p-(n-buty1amlno)-phenyl t-butyl ether.
2. An inhibitor for cracked gasoline comprising essentially p-(n-butylamino) -phenyl n-butyl ether. I
3. A process for stabilizing olefin-containing hydrocarbon 011 against deterioration of its valuable properties which comprises adding to said 011 a minor portion of a compound ing general structure:
wherein R and R are alkyl groups selected from the group consisting of normal butyl, isobutyl, secondary butyl and tertiary butyl groups.
4. An inhibitor for cracked gasoline comprising essentially p(n-butylamino)-phenyl-secondary-butyl ether.
'5. An inhibitor i'or cracked gasoline which comprises essentially a compound having the JOSEPH A. CHENICEK. ROBERT H. ROSENWALD.
gasoline compris-