Ether amine detergent and motor fuel composition containing same

A detergent additive represented by the formula: EQU R--[O--CH.sub.2 --CH(CH.sub.3)].sub.y --NH--(CH.sub.2).sub.3 --NH.sub.2 in which R is a hydrocarbyl radical having from 8 to 18 carbon atoms and y is about 2 to 6, and a gasoline motor fuel composition containing same.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
Modern internal combustion engine design is undergoing important changes to 
meet stricter standards concerning engine and exhaust gas emissions. One 
major change in engine design is the feeding of blow-by gases from the 
crankcase zone of the engine into the intake air-fuel mixture at the 
carburetor just below the throttle plate, rather than venting these gases 
to the atmosphere as in the past. The blow-by gases contain substantial 
amounts of deposit forming substances and are known to form deposits in 
and around the throttle plate area of the carburetor. Another significant 
change is the recirculation of a part of the exhaust gases to the fuel air 
intake of the engine. These exhaust gases also have deposit forming 
tendencies. The deposits caused by the recirculated gases, both blow-by 
and exhaust gases, restrict the flow of air through the carburetor at idle 
and at low speeds so that an over-rich fuel mixture results. This 
condition produces rough engine idling and stalling and leads to the 
release of excessive hydrocarbon exhaust emissions to the atmosphere. 
The noted design changes while effective for prompting a cleaner exhaust 
from the engine also leads to a fouling of the carburetor and therefore 
dictates the need for an effective detergent fuel composition in order to 
maintain the cleanliness and efficiency of the carburetor. 
2. Description of the Prior Art 
U.S. Pat. No. 3,980,450 discloses a carburetor detergent compound of the 
formula: 
##STR1## 
where R is a hydrocarbyl group containing at least 20 carbon atoms, 
R.sup.1 is a hydrocarbyl or amino substituted hydrocarbyl group and 
R.sup.2 and R.sup.3, which may be the same or different, are hydrogen 
atoms or alkyl groups and a gasoline composition containing same. 
U.S. Pat. No. 3,849,083 discloses a gasoline containing a carburetor 
detergent amount of ether amine selected from: 
I. R--O--L--NH.sub.2 
II. (R--O--L--).sub.2 NH and 
III. mixture containing (I) and (II) 
wherein R is selected from C.sub.1 -C.sub.40 alkyl groups, C.sub.6 
-C.sub.40 aryl groups and C.sub.3 -C.sub.40 alkenyl groups, and L is 
C.sub.2 -C.sub.8 alkylene, and additive concentrates suitable for blending 
into gasoline containing said ether amine detergent. 
U.S. Pat. No. 3,309,182 discloses polyether diamines as inhibitors of 
sludge sediment formation in petroleum distillate fuels. 
SUMMARY OF THE INVENTION 
This invention pertains to a carburetor detergent additive represented by 
the formula: 
EQU R--[O--CH.sub.2 --CH(CH.sub.3)].sub.y --NH--(CH.sub.2).sub.3 --NH.sub.2 
in which R is a hydrocarbyl radical having from 8 to 18 carbon atoms and y 
is about 2 to 6 and a motor fuel composition comprising a major portion of 
a mixture of hydrocarbons boiling in the gasoline boiling range containing 
same. 
The group R preferably contains 10 to 18 carbon atoms, most preferably from 
16 to 18. 
Also, y is preferably 2 to 5, most preferably about 2 to 4. 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The aminopropylated ether amines of this invention are represented by the 
following formula: 
EQU R--[OCH.sub.2 CH(CH.sub.3)].sub.y --NH--(CH.sub.2).sub.3 --NH.sub.2 
where R is a hydrocarbyl radical having 8 to 18 carbon atoms and y is about 
2 to 6 inclusive. 
These compounds are prepared using linear primary alcohols, having from 
about 8 to 18 carbon atoms as starting materials. These starting materials 
must first be propoxylated to add the desired number of propoxy groups to 
the alkyl moiety. The propoxylation reaction, which is essential for the 
aminopropylated ether-amines of this invention, is conducted by methods 
well known to those skilled in the art by reacting the linear primary 
alcohol with the propylene oxide in the presence of a catalyst, usually a 
basic material such as potassium hydroxide. 
The propoxylated alcohols are reacted with ammonia using a known method of 
catalytic liquid phase reductive amination. This step is accomplished via 
the procedures of U.S. Pat. No. 3,390,184 which is concerned with 
converting long chain secondary alcohols to the corresponding primary 
amines by reaction with ammonia in the liquid phase in the presence of a 
hydrogenation-dehydrogenation catalyst. 
The preferable catalyst of the ammonolysis would be one containing nickel, 
copper and chromium as described, for example, in U.S. Pat. No. 3,152,998. 
This catalyst is generally prepared by the reduction of a mixture of the 
oxides of nickel, copper and chromium in the presence of hydrogen at a 
temperature within the range of about 250.degree. to 400.degree. C. 
Calculated on an oxide-free basis, the catalyst contains 60 to 85 mole 
percent nickel. A particularly preferred catalyst composition is one 
containing 70 to 80 mole percent nickel, 20 to 25 mole percent copper and 
1 to 5 mole percent chromium. 
The ammonolysis reaction is generally conducted at a temperature of from 
about 190.degree. to about 250.degree. C. with the preferable range being 
about 200.degree. to about 240.degree. C. The pressure conditions for this 
reaction are from about 1000 to 5000 psig with the preferable range being 
from 1500 to 3000 psig, this pressure being partly due to the presence of 
excess hydrogen. Ammonia is introduced into the reaction such that the 
ammonia to alcohol mole ratio is from 5 to 40 moles of ammonia per 
hydroxyl group to be aminated. It is preferable that from about 10 to 30 
moles of ammonia per mole of alcohol be present. The reaction can be 
conducted either as a batch or a continuous reaction. 
The aminated material, now containing internal ether groups from the 
reaction with the propylene oxide and a primary amine group on one end of 
the molecule is reacted with one equivalent of acrylonitrile at 35.degree. 
C. in a methanolic solution to give the corresponding N-2-cyanoethyl 
derivative. This reaction solution was then hydrogenated at 120.degree. C. 
in the presence of six moles of ammonia per mole of nitrile, hydrogen and 
a cobalt-copper-chromium catalyst. The product is filtered and the ammonia 
and methanol is removed to yield the desired N-3-aminopropyl ether-amine: 
EQU CH.sub.3 (CH.sub.2).sub.8-18 CH.sub.2 [OCH.sub.2 CH(CH.sub.3)].sub.2-6 
NH(CH.sub.2).sub.3 NH.sub.2 
Specific examples of the aminopropylated ether amines of this invention 
include: N-1-(oleyl isopropoxyl)-1,3-propane diamine; N-1-[stearyl 
(polyisopropoxyl)3]-1,3-propane diamine; N-1-[octyl 
(polyisopropoxyl)1.75]-1,3-propane diamine; N-1-[eicosane 
(polyisopropoxyl)3.4]-1,3-propane diamine; N-1-[pentadecyl 
(polyisopropoxyl)4.1]-1,3-propane diamine; N-1-[isodecyl 
isopropoxyl]-1,3-propane diamine; N-1-[3-phenylisodecyl 
isopropoxyl]-1,3-propane diamine. 
The N-3-aminopropylated ether amines of the invention are employed in a 
gasoline motor fuel composition at a concentration effective to provide or 
to enhance the carburetor detergency properties of the fuel composition. 
In general, an effective concentration of the additive ranges from about 
0.00032 to 0.0192 volume percent based on the volume of the fuel 
composition with a preferred concentration ranging from about 0.00092 to 
0.0016 volume percent. The former limits correspond to from 1 to 60 PTB 
and the latter limits correspond to the preferred range of about 3 and 5 
PTB (pounds of additive per 1000 barrels of fuel). 
Methods for preparing the aminopropylated ether-amines useful in the 
present invention are as follows:

EXAMPLE I 
Propoxylation of a C16, C18 Linear Primary Alcohol: 
A clean and dry nitrogen purged 7-gallon kettle, equipped with stirring and 
heating means, was charged with 21.0 lbs (35.4 moles) of melted C16, C18 
linear primary alcohols (206-211 hydroxyl no.) and 30.0 grams of flaked 
potassium hydroxide. The mixture was heated to 120.degree. C. and then 
19.8 lbs (154.6 moles of propylene oxide were added over a period of 7.0 
hours. After allowing this reaction mixture to further digest for 2.0 
hours at 110.degree.-120.degree. C., 36 grams of oxalic acid were added at 
110.degree. C. to neutralize the basic catalyst. Then the whole mixture 
was filtered at 110.degree. C. to remove the formed salts. The product, a 
propoxylate alcohol of the formula: CH3(CH2)14,16CH2[OCH2CH(CH3)]4OH, was 
clear and colorless liquid (113.8 hydroxyl no.) with a molecular weight of 
493.1 (calculated). 
Reductive Amination of the Propoxylate Alcohol: 
This propoxylate alcohol was then reductively aminated in a 500 ml 
stainless steel continuous tubular reactor containing 475 ml of a 
proprietary nickel-copper-chromium catalyst (U.S. Pat. No. 3,152,998). The 
reaction conditions were as follows: 
______________________________________ 
Propoxylated alcohol, lbs/hr 
0.61 
Anhydrous ammonia, lbs/hr 
0.42 
Space velocity, g/ml cat/hr 
0.98 
75% H2:25% N2, 1/hr (STP) 
50 
Temperature, .degree.C. 
215.2 
Pressure, psig 2500 
Ammonia/organic (moles) 
20.1 
______________________________________ 
Prerun was 2.0 hrs and on-stream was 4.0 hrs. The effluent was stripped of 
ammonia and water to give a clear and colorless liquid ether amine 
product, CH3(CH2)14,16CH2 [OCH2CH(CH3)]4NH2, which analyzed as follows: 
______________________________________ 
Total titratable amine, meg/g 
1.82 
Primary amine, meg/g 1.74 
Hydroxyl no. 114.5 
% Nitrogen 2.73 
% Water 0.05 
______________________________________ 
The above titration techniques indicated that 89.2% conversion had been 
achieved and that the amine present contained 95.6% primary amine. 
Aminopropylation of the Ether-Amine 
A methanolic solution of the above-synthesized ether amine was reacted with 
one equivalent of acrylonitrile at 35.degree. C. to give the corresponding 
N-2-cyanoethyl derivative. This reaction solution was then transferred to 
a 1-gallon stirred autoclave and hydrogenated at 120.degree. C. in the 
presence of hydrogen, six moles of ammonia per mole of nitrile and 25 
grams of proprietary cobalt-copper-chromium catalyst per mole of nitrile. 
The maximum pressure in the autoclave was 1420 psig and the total reaction 
time was 12/3 hours. After filtration and ammonia and methanol removal, 
the desired N-3-aminopropyl ether-amine, CH3(CH2)14,16CH2[OCH2CH(CH3)]4 
NH(CH2)3NH2, a yellow to brown mobile liquid bottoms product, was obtained 
in excellent yield. Product structure was confirmed by nuclear magnetic 
resonance (NMR) and infrared (IR) spectra. The material analyzed as 
follows: 
______________________________________ 
Total titratable amine meg/g 
3.21 
Primary amine, meg/g 1.64 
Secondary + tertiary amine, meg/g 
1.52 
Total acetylatables, meg/g 
3.85 
% Nitrogen 4.49 
% Water 0.11 
______________________________________ 
EXAMPLE 2 
Propoxylation of a C10,12 Linear Primary Alcohol 
The mixture of decyl, dodecyl alcohol propoxylated was E(R) 1012 which 
is manufactured by the Ethyl Corporation. More specifically, E(R) 
contains 0.2 C6, 204 C8, 75.1 C10, 6.2 n-C12 and 16.1% iso-C12 alcohols 
(m.w. 162; 347 hydroxyl no.). The 1.75 mole propoxylate, 
CH3(CH2)8,10CH2[OCH2CH(CH3)]1.75OH (213.1 hydroxyl no.), was prepared 
according to the method of propoxylation described in Example I. 
Reductive Amination of the Propoxylated Alcohol 
This propoxylated alcohol was then reductively aminated in a continuous 
reactor by the reductive amination procedure described in Example I. A 
clear and colorless liquid ether amine product, 
CH3(CH2)8,10CH2[OCH2CH(CH3)]1.75 NH2, was obtained which analyzed as 
follows: 
______________________________________ 
Total titratable amine, meq/g 
3.59 
Primary amine, meq/g 3.49 
Hydroxyl no. 207.6 
______________________________________ 
The above titration techniques indicated that 97.0% conversion had been 
obtained and that the amine present contained 97.2% primary amine. 
Aminopropylation of the Ether-Amine 
The compound, CH3(CH2)8,10CH2[OCH2CH(CH3)]1.75NH (CH2)3NH2, was prepared 
from CH3(CH2)8,10CH2[OCH2CH(CH3)] 1.75NH2, by the same procedure for 
aminopropylation described in Example I. Product structure was confirmed 
by Nuclear Magnetic Resonance (NMR) and Infrared (IR) spectra. The 
material analyzed as follows: 
______________________________________ 
Total titratable amine, meq/g 
5.64 
Primary amine, meq/h 2.93 
Secondary + tertiary amine, meq/g 
2.60 
Total acetylatables, meq/g 
5.84 
% Nitrogen 7.84 
______________________________________ 
The base fuel employed for preparing the motor fuel composition of the 
invention comprises a mixture of hydrocarbons boiling in the gasoline 
boiling range. This base fuel may consist of straight chain or branched 
chain paraffins, cycloparaffins, olefins, aromatic hydrocarbons or any 
mixture of these. The base fuel can be derived from straight run naphtha, 
polymer gasoline, natural gasoline or from catalytically cracked or 
thermally cracked hydrocarbons and catalytically reformed stocks. 
The composition of hydrocarbon components of the base fuel is not critical 
nor does the octane level of the base fuel have any material effect on the 
motor fuel composition of the invention. 
The fuel composition may contain any of the additives normally employed in 
gasoline. Thus, the fuel composition can contain an anti-knock compound 
such as tetraalkyl lead compound, including tetraethylead, 
tetramethyllead, tetrabutyllead and mixtures thereof. The fuel composition 
can also contain anti-icing additives, dyes, upper cylinder lubricating 
oils and the like. 
The N-3-aminopropylated ether amine additive of the invention was tested 
for its effectiveness as a detergent in gasoline in the Chevrolet 
Carburetor Detergency Test. In this test, a gasoline fuel composition 
containing the additive is tested for its ability to remove preformed 
deposits from the throttle plate area in a carburetor. This test is run on 
a Chevrolet V-8 engine mounted on a test stand using a modified 
four-barrel carburetor. The two secondary barrels on the carburetor are 
sealed. The feed to each of the primary barrels is arranged so that the 
detergent additive fuel can run in one barrel and a reference fuel or a 
base fuel run in the other. The primary carburetor barrel was also 
modified to contain removable aluminum inserts in the throttle plate area 
so that the deposits formed on the insert could be conveniently weighed. 
The engine is run for a period of time usually 24 or 48 hours using the 
base fuel as the feed to both barrels with the engine blow-by circulated 
to the air inlet of the carburetor to cause a deposits build-up. The 
weight of the deposits on both sleeves is determined and recorded. The 
engine is then cycled for 24 additional hours with the reference fuel or 
base fuel being fed to one barrel and the additive fuel to the other. 
During this cycle, engine blow-by is circulated to the air inlet of the 
carburetor. The inserts are then removed from the carburetor and weighed 
to determine the difference between the performances of the 
additive-containing fuel of the invention and the reference fuel or base 
fuel for removing preformed deposits. After the aluminum inserts have been 
cleaned, they are replaced in the carburetor and the process repeated with 
the fuel feed inlet to the carburetor reversed in order to minimize 
differences in fuel distribution and carburetor construction. The results 
obtained in the fuel runs are averaged and the effectiveness of the 
reference fuel and of the additive fuel for removing deposits expressed in 
percent. 
The Base Fuel employed for testing the detergent additive of the invention 
is a premium grade gasoline having a Research Octane Number of about 92. 
This gasoline consists of about 30 volume % aromatic hydrocarbons, 17 
volume % olefinic hydrocarbons and 53 volume % paraffinic hydrocarbons and 
boils in the range from 90.degree. to 410.degree. F. This base fuel gives 
a Throttle Plate Merit Rating of about 3.6 in the Buick Carburetor 
Detergency Test. 
The carburetor detergency test results obtained from the base fuel, 
comparison fuels and the fuel compositions containing the 
N-3-aminopropylated ether amine prepared are set forth in Table I below: 
TABLE I 
__________________________________________________________________________ 
CHEVROLET CARBURETOR DETERGENCY TEST.sup.a 
Deposit 
Deposit 
wt. % 
Run No. 
Fuel Composition Build-up,mg.* 
Removed,mg. 
Percent Effective 
__________________________________________________________________________ 
1. Base Fuel 16.8 (+1.7)** 
+10** 
2. Commercial Detergent Fuel 20.2 16.0 -79 
3. Base Fuel + 50 PTB of Example II, 
CH.sub.3 (CH.sub.2).sub.8, 10 CH.sub.2 [OCH.sub.2 CH(CH.sub.3)].sub.1 
.75 NH(CH.sub.2).sub.3 NH.sub.2 
22.4 19.2 -86 
4. Base Fuel + 50 PTB 
CH.sub.3 (CH.sub.2).sub.19 [OCH.sub.2 CH(CH.sub.3)].sub.3.4 NH(CH.sub 
.2).sub.3 NH.sub.2 23.7 17.2 -73 
5. Base Fuel + 50 PTB of Example I, 
CH.sub.3 (CH.sub.2).sub.14, 16 CH.sub.2 [OCH.sub.2 CH(CH.sub.3)].sub. 
4 NH(CH.sub.2).sub.3 NH.sub.2 
22.4 19.6 -88 
__________________________________________________________________________ 
*Built up with base fuel. 
.sup.a Cleanup type test. 
**Deposit buildup. 
PTBpounds of additive per 1000 barrels of fuel. 
The fuel composition containing the aminopropylated ether-amine additive of 
the invention was outstanding as a carburetor detergent for removing 
preformed deposits from the throttle plate area of the carburetor. 
The additive of the invention was also tested for its effectiveness as a 
carburetor detergent in the Buick Carburetor Detergency Test. This test is 
run on a Buick 350 Cubic Inch Displacement V-8 engine equipped with a two 
barrel carburetor. The engine is mounted on a test stand and has operating 
Exhaust Gas Recirculation and Positive Crankcase Ventilation systems. The 
test cycle, shown in Table II, is representative of normal road operation. 
Approximately 300 gallons of fuel and three quarts of oil are required for 
each run. 
Prior to each run the carburetor is completely reconditioned. Upon 
completion of the run the throttle plate deposits are visually rated 
according to a Coordinating Research Council Varnish rating scale 
(Throttle Plate Merit Rating) where 1 describes heavy deposits on the 
throttle plate and 10 a completely clean plate. 
TABLE II 
______________________________________ 
BUICK CARBURETOR DETERGENCY TEST.sup.a 
Car- 
bur- 
etor 
Run Rat- 
No. Fuel Composition ing 
______________________________________ 
1. Base Fuel 3.6 
2. 5PTB of Example I, 7.9 
CH.sub.3 (CH.sub.2).sub.14,16 CH.sub.2 [OCH.sub.2 CH(CH.sub.3)].sub.4 
NH(CH.sub.2).sub.3 NH.sub.2 
3. 3PTB of Example I, 7.2 
CH.sub.3 (CH.sub.2).sub.14,16 CH.sub.2 [OCH.sub.2 CH(CH.sub.3)].sub.4 
NH(CH.sub.2).sub.3 NH.sub.2 
______________________________________ 
.sup.a Keep clean type test. 
The additive fuel composition consisting of the Base Fuel described above 
containing 3 PTB (pounds of additive per thousand barrels of fuel) of the 
aminopropylated ether amine substantially improves the Throttle Plate 
Merit Rating over that of the Base Fuel. 
The additive fuel composition consisting of the Base Fuel containing 5 PTB 
of the compound aminopropylated ether amine provides a surprising 
improvement in the Throttle Plate Merit Rating over that of both the Base 
Fuel and the additive fuel containing 3 PTB of aminopropylated ether 
amine. 
The improvement in the detergency property of the novel fuel compositions 
of the invention from the use of the novel detergent additives is a 
noteworthy advance in the provision of a modern detergent fuel 
composition.