DE1157033B - Preservation of kerosene fuels containing water against bacterial growth - Google Patents

Description

INTERNAT. KL. C 10 1

GERMAN

PATENT OFFICE

St 18462 IVd / 46 a ⁶

REGISTRATION DATE: OCTOBER 23, 1961

NOTICE THE REGISTRATION ANDOUTPUTE EDITORIAL: NOVEMBER 7, 1963

It is known that hydrocarbon fuels when stored in storage tanks, such as. Am Oil refineries, distribution stations and in the tanks for engine fuels, almost always small quantities Contain water at the bottom of the container. Some bacteria and types of sponges that are common found in the earth and in the groundwater, such reservoirs also occur in the water at the bottom before and remove the nutrients necessary for them as well as those in the hydrocarbon phase Trace elements contained in the water phase. Because of this metabolism, certain amounts of Petroleum products consumed; furthermore, this metabolism is the cause and effect of the corrosion of the tanks generally the products are soiled by the formation of rust, hydrogen sulphide, rubbery products, peroxides, acids, colored substances and hair fiber products in the boundary zone between the water and the hydrocarbons.

Bacteria seem to prefer hydrocarbons with a long carbon chain as food. The abovementioned bacteria are therefore particularly common in kerosene stores stored in water deposits and the life of these bacteria is far more difficult to control there than in gasoline stores stored in water deposits. Gasoline generally has a final boiling point below 238 ° C and often below 228 ° C. Even if the final boiling point is 238 ° C, the amount which has a boiling point above 228 ° C rarely exceeds 10%. Petrol has at least 40% components with a boiling point below 120 ° C. In the following, the term »kerosene« is intended to include hydrocarbon fuels in which at least 30% of the components boil above 228 ° C or in which no more than 15% of the constituents boil below 120 ° C or both criteria apply. Kerosene stocks are almost always unleaded, ie they do not contain any tetraalkyl lead compounds. Such products include diesel oil, which is a fraction of crude oil having a boiling point between about 150 and 37o ⁰ C and boiling at least 90% above 205 ⁰ C, as well as for aviation fuels Turbopropeller- or jet aircraft. These latter fuels are blends of petroleum fractions which must meet a number of requirements and which have a boiling range of approximately 38 to 315 ° C and preferably between approximately 65 and 290 ° C. The following data are used to explain a particular fuel, namely the preservation of water containing fuel

Kerosene fuels
against bacterial growth

Applicant:

The Standard Oil Company,
Cleveland, Ohio (V. St. A.)

Representative: Dr.-Ing. Dr. jur. F. Redies,

Dipl.-Chem. Dr. rer. nat. B. Redies

and Dr. rer. nat. D. Türk, patent attorneys,

Opladen, Rennbaumstr. 27

Claimed priority:
V. St. v. America, October 24, 1960 (No. 64 261)

Richard John DeGray, Shaker Heights, Ohio,

and Lawrence Neil Killian,

Bedford, Ohio (V. St. A.),

have been named as inventors

loaned JP-4, which made a fairly broad petroleum fraction represents.

Distillation sample

20% evaporates at 132 ° C
50% evaporates at 182 ° C
90% evaporates at 244 ° C

Residue 1.5 percent by volume

Loss 1.5%

Sulfur content .. max. 0.4 percent by weight

Melting point -6O ⁰ C

Kcal / kg 2093

Flash point -12 ⁰ C

As seen from the above data, 35% boil about the components above 205 ⁰ C. In the JP-5 fuel boiling between 80 and 90% above 205 ⁰ C. In a narrow kerosene fraction having a boiling point at 150 ° C ± 4 ° C boiling no component below 120 ° C.

Also, kerosene stocks appear to be more of a water-in-oil emulsion than gasoline stocks to stabilize the microbiological

309 747/197

Logical activity generated sludge and fibrous material is caused. Hence one stays Most of these impurities in the kerosene phase are suspended and easily clogged filters and Sieves in the storage and transport devices as well as the filters of machines that run on kerosene will.

Clogging of the filters is a particular because of the possibilities of engine failure serious moment in jet aircraft that are operated with kerosene-type fuels. In addition, the tendency towards clogging of filters in jet machines is made worse by the special feature Construction of this machine and the nature of its area are an effective solution to the above In order to achieve a problem, such a resistance must of course not occur, but the selected one bactericidal compound must kill the bacteria.

In addition, the selected compound must not change the properties of kerosene as a fuel. This requirement is particularly difficult to meet in cases where the fuel is for military Jet aircraft is intended, because of the very high requirements, especially what the Concerning freedom of fuels from precipitation. Fulfilling these requirements is one thing mandatory requirement for the usability of the fuel. Furthermore, the bactericidal treatment

partially supported. The amount of a 15 bond sufficient to be surface-active

A jet engine's fuel consumed is very large and can run up to 47001 per hour or more. With such large amounts of liquid, very low concentrations can occur in order to be able to penetrate through the hydrocarbon-water boundary layer into the water phase so that it can acts on the bacteria where they actually live. At the same time, the connection must be none

contaminating substances very quickly to disruptive 20 have such great surface activity that in

Residue quantities in the machine's filter system. It also has a jet in place of one single fuel tanks have a large number of interconnected cells with numerous deep-seated ones undesirable extent of water-in-oil emulsion is formed. Another requirement consists in that the compound has balanced properties in terms of extractability,

in places where water can collect 25 d. that is, it is not too easily extracted by water and in which the bacteria can live. In many cases it can be undesirable because in the other case one Jet aircraft, and especially military aircraft, have large amounts of communication through the water these fuel cells of a cleaning or deposits in the first storage tank of the distributor one Flushing out practically inaccessible, and the system is lost, which in turn results in Microbial growth can continue undisturbed and unchecked that insufficient amounts of the compound in kerosene. sin remain in order against those in the further tanks

It is already known the activity of sponges and bacteria in storage tanks of hydrocarbon fuels by treating the bacteria present in the distribution system or in the fuel tank or the machine itself can. At the same time, however, it is also important

Water phase of each fuel tank with a 35 that certain amounts of the compound through the

where X is hydrogen, the remainder

effective bactericide to combat and control. From the above it is easy to see that this mode of treatment in cases where the fuel tanks or fuel cells with a machine connected is not always feasible. In addition, such a control method is impracticable and uneconomical when protecting against the bacterial problem as a whole Fuel distribution system is desirable, because of the large number of tanks from which a such a system exists.

The bactericidal compound must be able to be added to the kerosene-like hydrocarbon, so that they carry the kerosene from one storage boiler to another and through the fuel system of the Machine in which the fuel is burned if necessary, can be transported further. on This way, an effective control of the bacterial activity before using the fuel can be achieved by simply adding the compound to the kerosene prior to its storage. To the To be able to fulfill its intended purpose, the bactericidal compound must meet a number of requirements fulfill. So the compound must be soluble in kerosene to such an extent that one for the Bacteria lethal concentration in the fuel is reached. In addition, the connection must have a have high bactericidal effectiveness. It has been found that some compounds, although initially the

Advancement of bacteria prevents that they mean 65 atoms of fuel,
but are only effective for a limited time because
the bacteria get used to the connections
and create a certain immunity to it. Around

Water deposits are extracted in the series connected tanks, so that there is a bactericidal Concentration can be achieved.

It has been found that a preservation of water-containing kerosene fuels against bacterial growth while meeting the above criteria in the best possible way by using Glycol borates of the general formula

BOX

,O,

or the rest

,O,

—R — Ο — Β

and R is an α- or /? - alkylene radical with 3 to 12 carbon

is achieved, wherein the glycol borate or a mixture of the glycol borates the kerosene in such

Amount is added that the content of the kerosene fuel of glycol borate, based on elemental boron, is at least 0.0005 percent by weight. Preferably, a glycol borate of the formula given above in which R is different from 1,3-propanediol is a derivative alkylene group, or a mixture of such a glycol borate and one in which R the alkylene group derived from a hexanediol is used.

The compounds used are prepared in a manner known per se.

The addition of hydrocarbon-soluble boric acid esters to hydrocarbon-based fuels is known per se. The additions were made to reduce the incineration of the fuels Precipitation occurring in the cylinder of the machine operated with it.

The amount of the boron compound to be added to the fuel in the present invention depends on various factors Factors. It has been found that to achieve a complete suppression of bacterial life the water phase must generally have a concentration of glycol borates which is about 0.05 percent by weight corresponds to elemental boron. The amount of glycol borate in kerosene that is preferably boron calculated is indicated, can based on this number together with the proportion of kerosene to Water and taking into account the distribution factor of the boron compound between the kerosene and the water phase can be estimated. The distribution factor can be easily calculated for each connection by simply Adding the same to a mixture of kerosene and water of known composition, separate determination the content of elemental boron in the kerosene and water phase and division of the larger ones Number can be obtained by the smaller number. When calculating the amount of water, that's not all Water in each individual tank must be estimated, but the number of water in the distribution system must also be estimated the tanks located through which the kerosene is pumped are taken into account, since each tank normally represents a new amount of water to be sterilized. The selected boron compound determines how much of the boron compound is in the water phase of the first tank is extracted and how much remains in the kerosene, to then between the kerosene and the Water to be distributed in the subsequent tanks of the distribution system. In general it can be said that the longer the carbon chain in the glycol portion of the boron compound, the less the boron compound is soluble in water or can be extracted by water. So is z. B. butylene glycol borate more water soluble than hexylene glycol borate, so a smaller amount of this compound in the kerosene of the first water-containing tank it would be necessary to have a concentration of 0.05% boron to generate in the water. However, since more butylene glycol borate in the first water excretion, with the If the kerosene comes into contact, there would be less boron compound in the kerosene for that remaining tanks in which contact with water deposits will take place than in the case of the heyxlene glycol borate. It can be seen from this that the choice of boron compound for a particular distribution system depends at least in part on how far through a tank distribution system such treatment is required throughout.

It must also be taken into account that not every batch of kerosene causes water deposits in everyone Tanks must transfer the full lethal dose of boron because subsequent batches of kerosene, the one Containing boron compounds can increase the boron content of the water up to a lethal dose. As from the above, the selected active ingredient or the active ingredient mixture to be used and the in the kerosene required amount of active ingredient for each ίο distribution system taking into account the above given considerations are elaborated. However, an amount of active ingredient that can be around 0.0002 Percentage by weight of boron in kerosene is equivalent to being regarded as the smallest amount at first Contact produces some obvious effect. The boron compounds are preferred in such Amounts of the kerosene added that they have a concentration between 0.0005 and 0.006 percent by weight Generate boron in kerosene, especially if two or more tanks are to be treated. the Use of amounts greater than 0.01% ■ is not required and is generally economical Reasons not justified either.

A surprising aspect of the invention lies in the fact that a5 is used to suppress bacterial activity a much lower boron content in the water phase in the form of the lipophilic organoboron compounds according to the invention is necessary than with the previously known treatment methods, according to which water-soluble Boron compounds added directly to the water deposits in the kerosene-containing storage tanks will. Since the growth occurs at the boundary phase, the transfer of the boron compound must from the kerosene to the water phase necessarily take place through this boundary phase. This does not take place instead of when the boron compound is in the water phase from the start, since in this case none Transfer from the water phase to the kerosene phase occurs.

The boron compound can be added directly to the kerosene stock in the necessary quantities. If desired, a concentrate of the boron compound can be prepared by using a solvent be prepared, the concentrate is then added to the kerosene, so the desired Adjust the boron concentration.

The invention will be better understood by describing a kerosene inventory test in which the actual storage conditions for such kerosene are mimicked via water separation so that the results are correlated to the actual results. This test consists in combining a kerosene stock containing boron compounds according to the invention with water in a ratio of 100: 1. In the test a device is used which consists of a large wheel with sixteen spokes, with two bottles similar to the "1 pint Mason" bottles attached to each other with the openings on each spoke. Each of the pairs of bottles was ^{filled with 400 cm 3} of the kerosene to be tested and 4 cm ^{3 of} water. A polished steel rod was placed in each pair of bottles so that the influence of the bacteria on the corrosion could be observed. The influence of rust formation on the development of the bacteria mimics the circumstances existing under actual storage conditions. The water was from

taken from an artificial lake that contains bacteria similar to those found in the water at the bottom of the tanks can be found. The wheel is then rotated at three revolutions per minute for 48 hours rotated to study the growth of bacteria, d. H. each pair of bottles is per revolution of the Turn the wheel twice so that the contents of the bottles appear six times per minute during the test flows back and forth. This movement mimics those processes that occur in a storage container, when large amounts of kerosene are introduced or discharged, causing the contents of the tanks to fall in a rolling motion is held.

At the end of the 48-hour test period, the bacterial density is estimated using the usual plate method. Here, plates are inoculated with a certain amount taken from the soil water and with progressive dilutions by a power of ten. For this purpose, an Icm ³ sample is pipetted off the water layer of the kerosene-water mixture and transferred to a sterile Petri dish. Then about 20 cm ^{3 of} a sterile agar solution are poured into the dish at a temperature of 40 ° C. and the contents swirled until completely mixed. The mixture on the plate is then allowed to cool to room temperature, whereupon the agar gels. The plate is then inverted and placed in an incubator held at 37 ° C. After 48 hours of incubation, the bacterial colonies are counted using an illuminated checkered plate. The result of the test is given in bacteria per cubic centimeter of the sample. The table below gives the results of this test with kerosene samples which had been untreated or treated with a bactericidal compound according to the invention. The kerosene used in this test was a product that meets the requirements of a JP-4 fuel.

as the number of carbon atoms in the glycol forming the boron compound increases, the amount of the elementary boron which enters the water phase decreases. It was also found that with the amount of the increase in the number of carbon atoms in the glycol constituting the boron compound of the elemental boron remaining in the kerosene after the first contact for the treatment of the further tanks in the distribution system. For this reason, it is often desirable to have one Mixture of a glycol borate derived from a short-chain glycol and one derived from a Use longer-chain glycol-derived glycol borate. This is especially true when 1,3-propanediol borate is used because it itself has only limited solubility in kerosene.

All kerosene products listed in the table have successfully passed the Erdco-Coker test in accordance Subject to the American regulations ASTM-D1660. This test is used to check whether the kerosene fuel is burning properly; he is often considered the most reliable Test viewed to determine the actual performance of fuel in turboprop and jet engines to predict. Mixtures 2, 3 and 4 showed no significant differences from Mixture 1 with respect to the amount or nature of the precipitate generated, from which it is to be concluded that the invention bactericidal substances do not have a harmful effect on the base fuel with regard to the Precipitation rate or in any other respect known to the inventor for use in Has turboprop and jet engines.

Claims (3)

PATENT CLAIMS: 1. Use of glycol borates of the general formula: 40 attempt Additive (concentration corresponds to 0.002 percent by weight boron) Bacteria per cubic centimeter BOX no additive (basic kerosene) 1,3-propanediol borate
(1: 1 connection) 50 mole percent 1,3-propanediol borate (1: 1 compound) + 50 mole percent 2-methyl-2,4-pentanediol borate
(1: 1 connection) 1,3-butanediol borate (1: 1 compound) 2-methyl-2,4-pentanediol borate (1: 1 compound) 000 ⁴⁵ wherein X is hydrogen, the remainder 40 120 - B. "O or the rest 3,200 55 60 —R — Ο — Β The above results clearly show that when in contact with only one body of water, 1,3-propanediol borate delivers the best results. It can be seen from the above results that each The greater the number of carbon atoms in the glycol forming the boron compound, the fewer the connection is effective on a first contact. In conclusion, it was found that and R is an α- or / 3-alkylene radical with 3 to 12 Carbon atoms means used to preserve water-based kerosene fuels against Bacterial growth, whereby the glycol or a mixture of the glycols the kerosene in such Amount is added that the content of the kerosene fuel based on glycol borate elemental boron, is at least 0.0005 percent by weight. 9 ίο 2. Use of glycol borates according to the Anlengruppe, and a glycol borate in which R Claim 1, characterized in that R is the Akylertvom which is derived from a hexanediol 1,3-propanediol derived alkylene group. group is represents. 3. Use of glycol borates, according to claim 1, characterized in that the GIy- 5 Kolborat a mixture of a glycol borate, in Ia considered publications: the R is the AJky French patent specification no. 1135 988, which is derived from propanediol. © 309 747/197 10.63