US2591583A

US2591583A - Rust preventive

Info

Publication number: US2591583A
Application number: US72099A
Authority: US
Inventors: Leonard E Moody; Jr James W Hand
Original assignee: Standard Oil Development Co
Current assignee: Standard Oil Development Co
Priority date: 1949-01-21
Filing date: 1949-01-21
Publication date: 1952-04-01
Anticipated expiration: 1969-04-01
Also published as: GB676650A

Description

Patented Apr. 1, 1952 UNITED STATES PATENT OFFICE 7 Leonard E. James .W.

Hand, Jr., Summit, N. J assignors to Standard' Oil Development Company, a corporation of Delaware N o Drawing. Application January 21, 1949,

Serial N0. 72,099

Claims. (01. 44-69) This present invention relates to a process for inhibiting therusting of metal surfaces, particularly when said metal surfaces are stored or otherwise idle. A further object ofthis invention is to contact the metal surfaces of an internal combustion engine with a fuel composition comprising gasoline containing tetraethyl lead with an organic halide which of itself is incapable of preventing rust, in admixture with oil soluble alkyl diamines as rust inhibitors. A more specific object of the present invention is to inhibit rust formation on the metal surfaces of an internal combustion engine, utilizing a gasoline containing tetraethyl lead and an organic halide in admixture with a lower alkyl diamine such as an ethylene, propylene, butylene or amylene diamine.

It is well known in the art to employ as fuels for'internal combustion engines, gasolines' containing tetraethyl lead and an added organic halide which functions as ascavenger agent for the lead. Internal combustion engines utilizing fuels of this character tend to form rust on the interior surfaces, particularly when left idle. The rust forming tendencies are greatly aggravated in the presence of wet or moist air. The problem is particularly acute with respect to aviation engines where the normal practice is to have a turn-about period during which time the aviation engine is left in an idle condition. Furthermore, aviation engines are normally stored for periods of time prior to their reinstallation in the plane. It is therefore, the object of the present invention to outline an improved process for taking internal combustion engines, especially aviation internal combustion engines out of service.

Various attempts have been mad to solve the problem of rust formation on the metal surfaces of internal combustion engines. One method employed is to add various inhibitors to the lubricating oils utilized in the engine crankcases. These compounded lubricating oils, however, can only contact certain internal metallic areas of the engine. These oils, do not have ready access to certain internal surfaces of the engine, especially the upper section of the cylinder liner in and near the combustion chamber, where the fuel enters. It is thus difiicultto inhibit these particular sections against rust. Therefore, it is a common and inconvenient practice to spray these sections through the spark plug holes with a compounded oil prior to storage. However,

neither complete coverage nor even distribution be attached to an of. the carbon atoms.

der liners and those metal parts of the engine to which only a fuel is'accessible. This is accomplished by adding to a fuel, such as; gasoline containing tetraethyl lead and an organic halide, an alkyl diamine. The loweralkyl diamines, as for example, the diaminescontaining .fro'm i2 to 5 carbon atoms, are especially suitable. These alkyl diaminesimay be added assingle compounds or as mixtures. For example, olefinic gaseous hydrocarbons containing from about 2 to.5 carbon atoms and taken from petroleum cracking operations may be halogenated and the products reacted with ammonia to form mixed diamines which are particularly suitable. Of the single compounds, propylene diamine in particular is preferred. I

The class of diamine addition agents of the present invention is represented by the following formula: H2NR-NH2, wherein R. represents an alkyl group of straight or branched chain structure and containing from 2-5 carbon atoms in the molecule. The amine groups may However, it is preferred that these groups be attached to different carbon atoms which are adjacent or are separated by not more than one carbon atom.

It has been found that these alkyl diamines when added to a fuel in a concentration in the range from about 0.03 to 5.0%, preferably in the concentration in the range from about 0.ll.0%, and said fuel composition is passed through an engine prior to storage, the critical metallic surfaces, including the cylinder liner area within the path of the piston travel, are protected against the formation of rust. It will be understood that although it is generally preferred to utilize the fuel of the invention for running the engine for a short period of time just prior to storage, the fuel can be employed for running the engine in normal operations over extended periods of time. In this case, relatively small amounts of the diamine can be employed. However, the concentration of diamine in the fuel should be greater than about 0.01% in order to obtain effective rust inhibition.

.In order to further illustrate the invention, the following example is given:

Example Various operations were conducted employing a one cylinder air-cooled Wisconsin internal combustion engine (AEH Motor). The Wisconsin engine had a cylinder made of nitrided steel (metal of the type used in aircraft engines), an. aviation fuel having a clear octane number of and containing 3.9 cc. of tetraethyl lead per gallon and having the followin Engler distillation was used in the various operations:

The leaded octane number was 96 A. S. T. M. and 98 Research. A lead scavenger agent comprising ethylene di-bromide was added to the fuel in a concentration of one theory of halogen per theory of lead.

vThe operations were conducted in two stages. In the first stage of the operation, the engine was run for 8 hours on the fuel composition. Inthe second stage of the operation, the engine was dismantled and the cylinder placed in a humidity cabinet for 5 days. At the expiration of 5 days, the extent rusting of the interior surface of the cylinder was determined and recorded as per cent rusting."

In operation A the aviation fuel containin the above identified quantity of lead and lead scavenger agent was run as described. In operation B the identical fuel composition was run except that 0.1% of propylene di-amine was used. The results of these operations are as follows:

It is evident that a substantial reduction in rust formation is secured by the composition of the present invention.

Having described the invention, it is claimed:

1; Improved leaded gasoline fuel which contains a lead scavenger agent and from about .03- 5% of an alkyl diamine selected from the class of diamines represented by the following formula: I-I2NR-NH2, wherein R represents an alkyl group containing from 2-5 carbon atoms.

2. A fuel composition as defined by claim 1 wherein the concentration of the diamine is in the range from about .1-1%

3. A composition as defined by claim 2 wherein the amine groups are attached to carbon atoms which are not separated by more than one other carbon atom.

4. The composition defined by claim 1 in which the said alkyl di-amine comprises propylene diamine.

5. The composition defined by claim 1 in which the said alkyl di-amine comprises a mixture of ell-amines containing from 2 to 5 carbon atoms.

LEONARD E. MOODY. JAB/[ES W. HAND, JR.

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

UNITED STATES PATENTS Number Name Date 2,433,716 Smith et a1 Dec. 30, 1947 2,447,615 Jones Aug. 24, 1948 2,496,444 Cook Feb. 7, 1950

Claims

1. IMPROVED LEADED GASOLINE FUEL WHICH CONTAINS A LEAD SCAVENGER AGENT AND FROM ABOUT .035% OF AN ALKYL DIAMINE SELECTED FROM THE CLASS OF DIAMINES REPRESENTED BY THE FOLLOWING FORMULA: H2N-R-NH2, WHEREIN R REPRESENTS AN ALKYL GROUP CONTAINING FROM 2-5 CARBON ATOMS.