Fuel Additive

Patentamt

JEuropaischesEuropean Patent Office (jj) Publication number: 0185 083 B1 Office europeen des brevets

® EUROPEAN PATENT SPECIFICATION

(45) Date of publication of patent specification: 22.08.90 (jjj) Int. CI.5: C 10 L 1/22 ® Application number: 85903467.0

(§) Date of filing: 06.06.85

(8) International application number: PCT/US85/01064

(fj) International publication number: WO 86/00088 03.01 .86 Gazette 86/01

3) FUEL ADDITIVE.

(§) Priority: 15.06.84 US 621073 ® Proprietor: KITCHEN, George Holcum P.O. Box 15212 ~ Rio Rancho, NM 87124 (US) (43) Dateof publication of application: 25.06.86 Bulletin 86/26 ® Inventor: KITCHEN, George Holcum _ P.O. Box 15212 (45) Publication of the grant of the patent: Rio Rancho, NM 87124 (US) 22.08.90 Bulletin 90/34

® zsj. „ . Representative: Sommerville, John Henry etal (H) Designated Contracting States: SOMMERVILLE & RUSHTON 11 Holywell Hill AT BE CH DE FR GB IT LI LU NL SE St. Albans Hertfordshire, AL1 1 EZ (GB)

@ References cited: FR-A-2177 954 FR-A-2411882 GB-A-1 398 067 US-A-1 973 676 m US-A-2 534309 US-A-3 334046 US-A-3493 354 US-A-3 888 773 US-A-3 907 518 US-A-4155 718 US-A-4 173456 US-A-4585462

i\oie. vvunin nine monins Trom tne puDiication or the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall ae filed in written reasoned a. a statement. It shall not be deemed to have been filed until the opposition fee has been said. (Art. 99(1 ) European patent convention). LU Courier Press, Leamington Spa, England. 1 EP 0 185 083 B1 2 Description the best yardstick of an inhibitor's usefulness in prolonging fuel storage life. The first test is a This invention relates to fuel additives and more variation of the color-stability test in Federal particularly to diesel fuel additives which inhibit Specification VV-K-211 Kerosene. In addition to the polymerization of fuel components, the growth 5 observing the color change, the amount of filter- of bacteria in stored fuel, and corrosion inside the able sludge and sediment is also measured. The fuel tank. It also relates to a method of storing fuel. second test is a prolonged version of the Gulf Oil With the increasing prevalence of standby Company's Fuel Corrosion of Steel Test. The Bell power generation equipment for essential ser- Laboratories' version of these tests have been vices, including hospitals, communication equip- io correlated against fuels actually stored in a stand- ment and the like, it has become increasingly by power fuel tank. The first test is run at 99°C important to protect the fuel from degradation (210°F) until an observable amount of sludge has when stored for long periods of time. More formed. This test is essentially an accelerated heat- recently, many of these standby motor generator stability test and is run in the absence of water. The systems have employed diesel engines making 15 second test is run at49°C (120°F) over water in the the stability of stored fuel an even more important presence of 1020 steel strip. This test is concluded consideration. Distillate fuels in general and diesel after 12 weeks or when an observable quantity of fuel in particular are prone with prolonged storage rust and sludge has been deposited. to form polymerizates which agglomerate into The accelerated heat-stability test is compara- what is referred to as sludge which can clog fuel 20 tively quick and useful for screening out the poorer lines and fuel injectors preventing the reliable additives; but because water is absent from this operation of the engine. In addition, water in the test, it is not capable of differentiating between fuel and in the form of condensates in a partially those additives that are either ineffective rust filled storage tank will attack the metal of the tank inhibitors, or incapable of protecting the fuels forming rust which also promotes the polymeriza- 25 when stored in contact with water and steel, and tion of components in the fuel. those that are effective under such storage con- In addition, new regulations promulgated by the ditions. It is precisely these conditions that are of Environmental Protection Agency have importance since stand-by fuels are frequently in recognised the problem of rusting tanks and contact with metal and condensate water, and require measures to prevent contamination of 30 rusting may be often as severe a problem as ground water which can occur from fuel leaking sludge formation. A 12-weekstability-and-rust test underground from rust perforated tanks. was designed to evaluate these effects. Likewise, sludge formation can be accelerated Because of the importance of stabilizing fuelsfor by the growth of bacteria in the fuel. extended periods of up to 10 years with the fuels in Therefore, modern inhibitors should have the 35 contact with metal and water, it is also important following characteristics in use. that the additive exhibit properties which would The material should be a sludge dispersant. It is enable it to be used as a reinhibitor and depoiy- known that the deterioration of fuel oils involves merizer during its repeated use over prolonged polymerization reactions resulting in the agglom- periods of time. eration of macroscopic polymerizates into sludge. 40 The major oil companies and chemical manufac- Although this reaction may be initiated by oxygen, turers have provided a wide variety of inhibitors. additives containing antioxidantsrsuch as hin- Exemplary of the types of materials available are dered phenols or diamines of the types used in the following: gasolines as gum inhibitors, are not totally effec- (1 ) nitrogen-containing, surface-active polymers tive for the purpose of preventing the polymeriza- 45 such as duPont FOA-11 and duPont FOA-208. tion mechanisms. The additive materials should (2) organic-soluble, surface-active, oxygenated also have rust-preventive properties. The additive amine such as Enjay Paradyne H04. This product materials should also be effective when the fuels may also contain a minor amount of a polymeric are stored in the presence of metals and water and dispersant. rust. The additive materials should also inhibit the so (3) anionic fuel additives such as Apollo SDI-2R, propagation of bacteria. a proprietary sludge inhibitor and dispersant as The kinds of bacteria that grow in stored fuels well as rust preventive, manufactured by Apollo thrive on nitrogen, sulfur, and phosphorus, as well Chemical Corporation. as iron, generally in theform of its oxides. Bacterial (4) chelating-type metal deactivator such as an growth can be reduced, if not eliminated, by 55 80% solution of N, N' disalicylidene-1-2 propane- employing the following preventive measures. A diamine in aromatic solvents. biocide should be employed. Of course, the elimi- (5) a film-forming metal deactivator such as nation of materials in the fuel tank that contain Vanlube 601, R.T. Vanderbilt Company. nitrogen, sulfur or phosphorus would be helpful. (6) an antioxidant such as 2,6 ditertiarybutyl-4- Since the latter measure is practically impossible, 60 methylphenol provided in Enjay Parabar 441, and these materials must be considered in theformula- also, duPont A029. tion of any additive. In addition, it is important to To varying degrees, these materials alone or in keep the fuel tanks clean and dry, in order to various combinations have in the past provided reduce or eliminate rust formation in the tanks. some measure of protection for stored fuel with Two standard test methods have been used as 65 respect to some of the major properties required.

2 3 EP 0185 083 B1 4 For very long term storage however, it is essen- frequency such as to (a) solubilize or subdivide tial that the inhibitor employed be capable of any macroscopic sludge present, (b) disperse any being employed during routine maintenance to submacroscopic sludge agglomerates present, depolymerize and disperse the sludge that is whereby to retard or prevent any subsequent inevitably formed. 5 agglomeration, and (c) minimise the effect of The document GB-A-1398067 is concerned with bacteria, oxygen and rust formation on polymeri- detergent additives for inhibiting deposits in fuels zation in the fuel. and comprising a high molecular weight hydro- As previously described, a wide variety of carbyl amine, either or both of which may be a chemical compositions have been provided as polymerised ethylene diamine. A poly a-olefin 10 fuel additives. Unfortunately, many of these com- synthetic lubricant may also be present. positions when used as recommended by their The document US-A-3334046 is concerned with manufacturers do not provide all of the properties the use of substituted 1,3,5-triazines as stabilizers which overall are required in an effective of organic material normally subject to deterior- inhibitor, or reinhibitor and depolymerizer for the ation, though no mention is made of these com- 15 long term storage of kerosene and diesel fuel. pounds being suitable for such other uses as, for The composition of the present invention example, biocidal inhibitors. utilizes a major proportion of a proprietary com- It is also important that attempts to eliminate position presently sold by the Ethyl Corporation the problem of injector clogging at low tempera- under the trademark EDA-3. ture by the build-up of hydrocabon waxes in the 20 This clear amber liquid composition contains a fuel does not compound injector scoring high molecular weight amine, is basic and is problems by reducing or eliminating the lubricity believed to be a polymerization product of an a of the fuel. It is therefore an objective of the homologue of ethylene diamine. The boiling present invention to provide a diesel fuel additi- point range of this composition begins at about tive which inhibits the formation of sludge, and 25 240°F (1 16°C). It is insoluble in water. bacteria, in the fuel during long periods of This composition is recommended by the storage. It is a further objective of the present manufacturer as the sole fuel additive to be used invention to provide a fuel additive which inhibits as an inhibitor of sludge formation. In addition to the formation of rust in diesel fuel storage tanks. the foregoing, the EDA-3 contains additives which It is yet another objective of the present inven- 30 inhibit rust, such as certain chelating agents, and tion to provide a fuel additive composition which which help to demulsify and disperse sludge that is capable of depolymerizing and dispersing is formed. sludge and sludge forming polymers in diesel fuel At 100% usage, however, this composition and kerosene stored for long periods of time. does not properly diffuse in the fuel sufficiently to It has been discovered that a fuel additive 35 effectively provide any depolymerization func- comprising a major proportion of a high mole- tion. When this composition is diluted with an cular weight amine, and minor proportions of aromatic naphtha solvent (in a manner contrary naphtha and a poly alpha olefin synthetic oil, to what the manufactuer of the composition together with a small amount of biocide can be recommends), in the proportions described combined with distillate fuels such as kerosene 40 hereinafter, the combination provides a more and diesel fuels in a ratio of about one part workable, effective depolymerizing agent which additive to about 3,000 to about 10,000 parts of also helps to prevent wax build-up which can be a fuel to produce a polymerization and bacteria problem in severe cold. Preferably, a naphtha, inhibitor, as well as a rust inhibitor which is purchased from Union Chemicals Division of capable of depolymerizing and dispersing sludge 45 Union Oil Company of California, designated HA- and sludge forming polymers in stored fuel. 40, is used. This composition contains single and According to the invention in a first aspect, a double ring aromatics having a boiling range of fuel additive for stored fuel, capable of reducing from about 420°F (216°C) to about 545°F (285°C) the amount of macroscopic sludge particles and a specific gravity at 60°F (16°C) of about 0.98. formed from polymerization reactions promoted so This composition is also not soluble in water. by bacteria, comprises: more than 50 parts by Due to the strong solvent action of the naphtha, weight of a polymerization product of ethylene it is desirable for the composition to contain a diamine or of a homologue of ethylene diamine, minor proportion of a poly alpha olefin, non- or a mixture of such polymerization products; compounded synthetic oil such as Synfluid 6 as about 25 parts by weight of an aromatic naphtha 55 sold by the Gulf Oil Company. This aliphatic solvent having a boiling point in the approximate hydrocarbon based synthetic oil, when used in range 420°F (216°C) to 545°F (285°C); about 25 the composition in about 25 parts per 100 parts of parts by weight of a poly alpha olefin synthetic oil total composition, helps to provide the required to assist lubricity; and an effective amount of lubricity for diesel injectors, pumps and the like. Hexahydro-1,3,5-Tris (2 Hydroxyethyl) S-Triazine 60 Finally, most fuel additive compositions biocide. attempt to prevent polymerization due to bacteria According to the invention in a second aspect, a growth and the subsequent sludge formation, by method of storing fuel in a tank is characterized in the use of up to 5% by weight of a biocide. that a fuel additive according to said first aspect is Contrary to this prior practice, it has been found in periodically added to the fuel in amounts and at a 65 the present composition that about 0.05 parts per

3 5 EP 0 185 083 B1 6 100 parts of the composition is an adequate level comprising: more than a 50 parts by weight of a for the biocide selected. The preferred biocide polymerization product of ethylene diamine or of used in the present invention is Hexahydro-1,3,5- a homologue of ethylene diamine, or a mixture of Tris (2-Hydroxyethyl) S-Triazine (C9H2, N303). This such polymerization products; about 25 parts by component is sold by ONYX Chemical Company 5 weight of an aromatic naphtha solvent having a of Jersey City, New Jersey under the trademark boiling point in the approximate range 420°F ONYXIDE 200. (216°C) to 545°F (285°C); about 25 parts by weight To properly prepare the composition of the of a poly alpha olefin synthetic oil to assist present invention, the ONYXIDE 200 is first added lubricity; and an effective amount of Hexahydro- to one half of the HA-40. The poly alpha olefin is 10 1,3,5-Tris (2 Hydroxyethyl) S-Triazine biocide. then added to the HA-40 and ONYXIDE 200. Next, 2. A fuel additive according to Claim 1, charac- the EDA-3 is added to the other half of the HA-40 terized in that the biocide is present in amounts of andthen the two HA-40 components are about 0.05 parts by weight of the fuel additive. thoroughly mixed together. 3. A method of storing fuel in a tank, charac- The most preferred composition contains the 15 terized in that a fuel additive according to Claim 1 following proportions: or Claim 2 is periodically added to the fuel in 50 parts by weight EDA-3 amounts and at a frequency such as to (a) solu- 24.95 parts by weight HA-40 bilize or subdivide any macroscopic sludge 25 parts by weight of Poly alpha olefin present, (b) disperse any submacroscopic sludge .05 parts by weight ONYXIDE 200. 20 agglomerates present, whereby to retard or pre- As previously discussed, the prior composi- vent any subsequent agglomeration, and (c) mini- tions for inhibiting the formation of sludge form- mise the effect of bacteria, oxygen and rust ing polymers, bacteria, and for the prevention of formation on polymerization in the fuel. rust in fuel storage tanks were not particularly effective when subsequently applied to fuel 25 Patentanspriiche storage tanks where polymerization and sludge had already formed to any substantial extent. 1. Brennstoff-Additiv fur gelagerten Brennstoff, Without being bound to any particular theory, it is der geeignet ist, die Menge von makroskopischen postulated that macroscopic sludge, even if Schmutzpartikeln zu verrringern, die durch Poly- temporarily soiubilized by other additive com- 30 merisationsreaktionen, unterstiitzt durch Bakte- positions, such as present in EDA-3, tends to rien, gebildet wurden, und die Oxydation, wobei reagglomerate relatively quickly thereby posing das Additiv folgendes enthalt: mehr als 50 the same drawbacks to the fuel pick up, transfer Gewichtsanteile eines Polymerisationsprodukt.es and engine injector systems. von Ethylendiamin oder eines Homologes von The composition of the present invention after 35 Ethylendiamin oder einer Mischung solcher Poly- successfully solubilizing or subdividing the merisationsprodukte; ungefahr 25 Gewichtsan- macroscopic sludge also provides the capacity of teile eines aromatischen Benzinlosungsmittels dispersing the submacroscopic sludge mit einem Siedepunkt im Bereich von ungefahr agglomerates thereby retarding subsequent reag- 420°F (216°C) bis 545°F (285°C); ungefahr 25 glomeration. This action in concert with the in- 40 Gewichtsanteile eines PolyalphaolefinsynthetikO- hibition of polymerization provided by the com- les, um die Schmierfahigkeit zu unterstiitzen; und ponents of the composition, in the quantities eine wirksame Menge von Hexahydro-1,3,5-Tris recited has been shown to be an effective fuel (2 Hydroxyethyl) S-Triazin Biozid. additive for stored fuel when used in a routine 2. Brennstoff-Additiv gemalS Anspruch 1, program of preventative maintenance. 45 dadurch gekennzeichnet, dafi das Biozid in The particular action described apparently Mengen von ungefahr 0,05 Gewichtsanteilen des minimizes the effect of bacteria, oxygen and even Brennstoff-Additives vorhanden ist. rust formation on the polymerization 3. Verfahren zur Lagerung von Brennstoff in mechanisms that can occur in stored fuel. einem Tank, • Since none of the prior compositions com- so dadurch gekennzeichnet, dalS ein Brennstoff- pletely eliminate the formation of agglomerated Additiv gemafi Anspruch 1 oder 2 periodisch dem polymerizates in the form of gels and sludge it Brennstoff in solchen Mengen und zu einer sol- has been important to find a composition and chen Haufigkeit zugefiigt wird, dal5 (a) jeder vor- method for reducing the deleterious effects from handene makroskopische Schmutz loslich such activity. In comparison tests, such as those 55 gemacht oder aufgespalten wird, (b) jede vorhan- previously employed, the composition of the dene submakroskopische Schlamm-Agglomerate present invention has provided a hitherto dispergiert werden, wodurch jede nachfolgende unachieved benefit in this field. Agglomeration verzogert oder verhindert wird, und (c) die Wirkung von Bakterien, Sauerstoff und Claims 60 Rostbildung auf eine Polymerisation in dem Brennstoff verringert werden. 1. A fuel additive for stored fuel, capable of reducing the amount of macroscopic sludge particles formed from polymerization reactions promoted by bacteria, and oxidation said additive 35

4 7 EP 0 185 083 B1 8 Revendications 2. Additif selon la revendication 1, caracterise en ce que le biocide est present 1. Additif pour du combustible stocke, a raison d'environ 0,05 partie en poids destine a reduire la quantite de particules dans I'additif. macroscopiques de boue formees par des s 3. Procede de stockage de connbustible reactions de polymerisation produites par dans un reservoir, caracterise en ce qu'un des bacteries, ainsi que I'oxydation, I'additif additif selon la revendication 1 ou 2 est comprenant: plus de 50 parties en poids ajoute periodiquement au combustible en d'un produit de polymerisation de la dia- quantites et a une frequence qui lui per- mine d'ethylene, ou un melange de tels 10 mettent de: (a) solubiliser ou subdiviser produits de polymerisation; environ 25 par- toutes boues macroscopiques existantes, (b) ties en poids d'un solvant aromatique disperser tous agglomerats existants de naphte ayant un point d'ebullition compris boues submacroscopiques, de maniere a approximativement entre 216°C (420°F) et retarder ou empecher toute agglomeration 285°C (545°F); environ 25 parties en poids 15 subsequente, et (c) minimiser I'effet des d'une huile synthetique de poly-alpha-olefine bacteries, de I'oxygene et de la formation pour contribuer a I'onctuosite; et une quan- de rouille sur la polymerisation dans le tite efficace de biocide d'hexahydro-1,3,5- combustible. tris(2-hydroxyethyle)S-triazine.