Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/10—Liquid carbonaceous fuels containing additives
  • C10L1/14—Organic compounds
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/10—Liquid carbonaceous fuels containing additives
  • C10L1/14—Organic compounds
  • C10L1/22—Organic compounds containing nitrogen
  • C10L1/228—Organic compounds containing nitrogen containing at least one carbon-to-nitrogen double bond, e.g. guanidines, hydrazones, semicarbazones, imines; containing at least one carbon-to-nitrogen triple bond, e.g. nitriles
  • C10L1/2283—Organic compounds containing nitrogen containing at least one carbon-to-nitrogen double bond, e.g. guanidines, hydrazones, semicarbazones, imines; containing at least one carbon-to-nitrogen triple bond, e.g. nitriles containing one or more carbon to nitrogen double bonds, e.g. guanidine, hydrazone, semi-carbazone, azomethine
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/10—Liquid carbonaceous fuels containing additives
  • C10L1/14—Organic compounds
  • C10L1/26—Organic compounds containing phosphorus
  • C10L1/2633—Organic compounds containing phosphorus phosphorus bond to oxygen (no P. C. bond)
  • C10L1/2658—Organic compounds containing phosphorus phosphorus bond to oxygen (no P. C. bond) amine salts

Definitions

• thermal stability requirement which may be determined in a CFR fuel coker, a laboratory apparatus designed to measure the high temperature stability of jet fuels by subjecting the test fuel to the same level of temperature stress and in a manner similar to that occurring in jet engines.
• CFR fuel coker a laboratory apparatus designed to measure the high temperature stability of jet fuels by subjecting the test fuel to the same level of temperature stress and in a manner similar to that occurring in jet engines.
• the fuel Before the fuel is combusted it is preheated, for example, by the hot operating engine itself, in which case the fuel, which is pumped through feed lines under pressure, serves as coolant for the engine while on its way to the combustor. Before entering the combustor, the fuel may attain temperatures ranging from 300 to 500 F.
• Varnish-like deposits may accumulate in the feed lines, on filter screens, and in feed orifices leading into the combustion chamber, and particles of sludge may become lodged in the orifices and trapped in the filter systems.
• Such accumulations are harmful, as they may lead to engine malfunctions by restricting the flow of fuel to combustor, impeding heat transfer through the metal of the feed lines, and causing imperfect flame patterns around the orifices when the fuel is ignited.
• an approved corrosion inhibitor which is understood to consist essentially of an oil-soluble n-alkyl primary amine salt of an acid alkyl phosphate, while efiective to improve the filterability of the fuel (as well as to inhibit corrosion),
• the object of this invention is to provide jet fuels having improved thermal stability.
• the object of the present invention is to provide significantly improved jet fuels by incorporating into said fuels the hereinafter described soluble additives of the approved classes of metal deactivator and corrosion inhibitor compositions which function compatibly to inhibit the deterioration of the fuel under conditions of thermal stress.
• the present invention relates to a thermally stabilized jet fuel comprising essentially a jet fuel and, as thermal stabilizers therefor, from about 1 to 10 lbs. per 1000 barrels of an N,N-disalicylidene-aliphatic polyamine and from 5 to 50 lbs.
• the present invention is directed to the operation of a jet engine in which the jet fuel to be combusted is in heat-exchange relationship with the hot engine, in which method of operation the step of stabilizing the jet fuel against thermal deterioration while in such a heat-exchange relationship is accomplished by introducing into said fuel before the fuel enters into said heat-exchange relationship an N,N'-disalicylidene-aliphatic polyamine compound and an amine salt of an acid alkyl phosphate, said amine salt and alkyl phosphates as above defined.
• This invention is based on the discovery that the described additives, in combination in jet fuel, inhibit the thermal deterioration of the fuel while it is under conditions of thermal stress such as those occurring in a jet engine, and thereby provide for substantially clean, deposit-free flow of fuel from fuel tank to combustor.
• the additives of this invention exert an unexpected combined effect to maintain the flow of fuel through the feed lines and filter system and to inhibit the deposition of sludge and varnish-like deposits in these parts. It is also significant that these additives impart, to the fuel, properties of anti-corrosion and metal deactivation, as might be expected, and have no adverse elfect on other properties of the fuel such as its waterreaction.
• the amine salts of the acid alkyl phosphates are prepared simply by neutralizing an acid alkyl phosphate or pyrophosphate with the appropriate amine to a pH of about 6-7.
• the acid alkyl phosphates and pyrophosphates are obtained by reacting an alcohol with phosphoric anhydride (P From about 2 to 4 moles of a primary alkanol or mixture of such alcohols may be employed per mole of P 0
• Preferred for the present purpose are the ap proximate equimolar mixtures of the monoand dialkyl phosphates produced on using 3 moles of alcohol per mole Of P205.
• the alkanol will be a primary alkanol, and preferably a branched primary alkanol, having 8 to 18 carbon atoms.
• Examples are the normal alkanols derived from coconut kernel oils.
• One such fraction available commercially, consists mainly of the n-octyl and n-decyl alcohols.
• Another consists largely of n-dodecyl alcohol but contains other n-alkanols containing from 10 to 18 carbon atoms.
• Still another ranges from n-C to n-C with n-C predominating.
• the alcohol will be a mixture of branched chain primary alkanols, such as those produced in the well-known Oxo process from C0, H and a branched chain olefin.
• branched chain primary alkanols such as those produced in the well-known Oxo process from C0, H and a branched chain olefin.
• these are the 0x0 octyl, decyl, tridecyl and octadecyl alcohols, all of which are mixtures consisting predominantly of branched chain primary alkanols obtained from propylene-butylene dimer, tri-propylene, tetra-propylene and penta-propylene, respectively.
• the amine salts of the subject compositions will be fuel-soluble substituted ammonium alkyl phosphates prepared by neutralizing an acid alkyl phosphate with a C to C non-aromatic monoamine which broadly may be a primary amine containing a tert-alkyl substituent on nitrogen, or a secondary or tertiary amine containing monovalent aliphatic or cycloaliphatic hydrocarbyl substituents on nitrogen.
• the amine will be a C to C tert-alkyl primary amine, and preferably the amine salt will be the salt of such an amine and the acid phosphate derived from the mixed octyl alcohols made by the 0x0 process.
• the tert-alkyl amines used to prepare these preferred additives are: 1,1,3,3-tetramethylbutyl amine (tert. octyl amine); the mixed tert. alkyl amine fractions having from 12 to 14 carbon atoms and from 18 to 21 carbon atoms, respectively, such as those marketed commercially under the trade names Primene 81- R and Primene JM-T; and tert. nonyl amine, also available commercially, consisting mainly of the C with small amounts of C and C amines and having a molecular weight range of 143 to 157.
• Secondary amines and tertiary amines are diisopropylamine, di-Z-ethylhexylamine, N- octenyl-cyclohexylamine, tributylamine, triisooctylamine, and N,N-diethylcyclohexylamine.
• the amine salts consist of two main species which may be schematically represented as follows:
• the metal deactivator component of the subject compositions may be prepared by reacting the appropriate o-hydroxy aromatic carbonyl compound with a polyamine having two NH groups, e.g., 1,2-propane diamine and ethylene diamine, as described in US. 2,181,121, 2,255,- 597 and 2,813,080.
• Metal deactivators comprised essentially of the reaction products obtained from salicylaldehyde and 1,2-propane diamine are preferred, e.g., N,N- disalicylidene-l,Z- ropanediamine.
• Others which may be used are derived from mixtures of salicylaldehyde and o-hydroxyacetophenone and 1,2-propane diamine or mixtures of this diamine with diethylenetriamine, as described by Bartlett in U.S. 2,813,080.
• the preferred metal deactivators are derived from o-hydroxy aromatic aldehydes whose major component is salicyladehyde, they may be regarded as consisting essentially of N,N-disalicylidene compounds.
• metal deactivator compositions in addition to containing the N,N'-disalicylidene compound as the active ingredient, will ordinarily also contain, particularly in their commercial forms, diluents such as xylene or a combination of such a liquid aromatic hydrocarbon with a phenol such as xylenol, as described by Bartlett in US. 2,813,080.
• diluents such as xylene or a combination of such a liquid aromatic hydrocarbon with a phenol such as xylenol, as described by Bartlett in US. 2,813,080.
• the actual quantities employed in a given fuel will depend largely on the susceptibility of that fuel to thermal deterioration in use. In general, however, about 7.5 to 30 lbs. of an amine salt such as the Primene 81- R salt of the mixed Oxo octyl phosphate, and not more than about 2 lbs. of a metal deactivator such as N,N'-disalicylidene-1,2-propane diamine, per 1000 barrels of jet fuel, will be preferred.
• the fuel-soluble amine salt and metal deactivator compositions are homogeneously incorporated into the jet fuel simply by agitating.
• these two essential additives are separately added to and blended into the jet fuel to be stabilized.
• the additives are conveniently handled in liquid form, i.e., as concentrates in hydrocarbon solvents such as kerosene for the amine salt and xylene or xylene-xylenol combination for the metal deactivator.
• the jet fuel may also contain an antioxidant of the alkyl phenolic or aromatic amine type such as 2,6-di-tertiary butyl-p-cresol or N,N'-disecondary butyl-p-phenylenediamine.
• an antioxidant of the alkyl phenolic or aromatic amine type such as 2,6-di-tertiary butyl-p-cresol or N,N'-disecondary butyl-p-phenylenediamine.
• Anhydrous phosphoric pentoxide (P 0 is added gradually under anhydrous conditions to 3 molar equivalents of the alcohol under agitation.
• the addition of P 0 is regulated so as to maintain the reaction temperature in the range 40 to 90 C. (Good results are ordinarily obtained either at 50: 10 C. or at il 0 C.)
• the reaction mass is held at 6070 C. for about 12 to 24 hours to complete the reaction (the course of which may be followed by conventional methods of analysis for reactants and products).
• the acid alkyl phosphate is a viscous o1
• the amine salt is obtained by neutralizing the aboveproduced acid alkyl phosphate to a pH of about 7 by the addition thereto of approximately 2 moles of amine per mole of P 0 originally employed.
• the amine, together with sufiicient kerosene to produce a final solution containing about 80% of the neutralized salt as the active ingredient is added gradually to the acid phosphate under agitation, and the reaction mass held at 70:10" C. until it becomes completely homogeneous.
• the neutralized salt-kerosene compositions are relatively mobile liquids at ambient temperatures.
• a barrel of jet fuel in the following examples represents 42 U.S. gallons and a specific gravity within the range of 0.739 to 0.845.
• the fuel coker is a laboratory apparatus designed to measure the fuels high temperature stability. In principle, it subjects the test fuel to the same level of temperature stress and in a manner similar to that occurring in jet engines.
• the unit consists essentially of a fuel system, a preheater and a heated filter section.
• the preheater which simulates the hot fuel line sections of the engine, consists essentially of two concentric aluminum tubes, the inner tube housing an electric heater.
• the heated filter section which is heated electrically and which represents the nozzle area of the engine where fuel degradation particles may become trapped, contains a sintered stainless steel filter that serves to trap such degradation particles forced in the fuel during the test. The extent of this build up of trapped particles is transmitted as a pressure drop across the filter.
• the fuel enters the preheater through a fuel inlet body and passes between the inner and outer tu bes where it is heated to the required temperature by the heater contained in the inner tube.
• the heated fuel leaves the preheater through an outlet body where its temperature is measured by means of a thermocouple.
• the hot fuel then enters the heated filter section which also contains a thermocouple for measuring its temperature. Pressure taps before and after the filter section lead to a manometer Where the pressure drops across the filter is measured.
• the fuel presure was 150 pounds and the fuel flow rate 6 pounds/hr.
• the preheater temperature was 300 or 350 F. and the filter temperature 400 F.
• the preheater temperature was 400 F.
• the filter temperature 500 The fuel was passed through the unit for 300 minutes or to a pressure drop of 25 inches of mercury across the filter. If a pressure drop of 25 inches occurred before 300 minutes had elapsed, the run was stopped to remove the filter and then continued to 300 minutes.
• 3-and 4-ratings are apparently the most significant, an abbreviated notation is employed in report ing the present results.
• the tube deposit ratings are expressed as follows: the sum of the 13 individual ratings, followed by the total number of 4-ratings, followed by the total number of 3-ratings. (The difference between the sum total of the 13 ratings and the sum of all the 4- and 3-ratings is the sum of the 0-, 1- and Z-ratings.)
• Example 2 was repeated, using the fuel of Example 2, 2 lbs./ 1000 bbls. of DMD and 15 lbs/1000 bbls. of each of the following fuel-soluble secondary amine salts of mixed monoand dialkyl phosphates:
• E diisopropylammonium OX0 tridecyl phosphate
• F di-2-ethylhexylammonium C -C n-alkyl phosphate
• G di-2-ethylhexylammonium 0x0 octyl phosphate
• H piperidinium 0x0 octyl phosphate
• I di-2-ethylhexylammonium n-butyl and isoamyl phos- 7 phate prepared from a 1:1 molar mixture of butyl and isoamyl alcohols
• J N-(octeny1)-cyclohexy1ammonium x0 octyl phosphate
• J N-(octeny1)-cyclohexy1ammonium x0 octyl phosphate
• Tests 14 and 15 are for comparison only, amine salts H and I being outside the scope of the invention for reasons of inoperability. Amine salt F appears to be marginally effective in reducing tube deposits, though it greatly aids filterability. Comparison of test 12 with test 13 (and with tests 11 and 16) explains the preference for the branched primary alkyl groups in the phosphate; test 14, however, shows that this feature alone is not enough to provide the desired results.
• EXAMPLE 4 The following results were obtained, using the fuel of Example 2, 2 lbs/1000 bbls. of DMD and 15 lbs./ 1000 bbls. of each of the following fuel-soluble tertiary amine salts of mixed 1:1 Oxo octyl phosphate:
• K tributylamine salt
• L N-diethylcyclohexylamine salt
• EXAMPLE 5 The J-P-S jet fuel of Example 1 was treated to contain 2 lbs/1000 bbls. of DMD and lbs/1000 bbls. of each of the following amine salts of the mixed 1:1 Oxo octyl phosphate, or of commercial additive Q:
• B the Primene 81-R salt
• K tributylamine salt
• M triisooctylamine salt
• N 2-ethylhexylamine
• Example 6 The JP-S of Example 1 was treated to contain DMD and fuel-soluble additives A of Example 1, K of Example 5, N of example 5, and P, the tert. nonlyamine salt of the mixed 1:1 monoand di-Oxo octyl phosphate, in the quantities given below.
• Tests 33 and 34 are for comparison.
• Additive N the Z-ethylhexylamine salt, is excluded from the scope of the invention.
• the compatibility of the subject additives with DMD in fuel under accelerated storage conditions is noteworthy.
• Example 6 was repeated on the JP-S fuel of Example 1, with and without the combined additives DMD and A of Example 1. The following results were obtained in the fuel coker test after the treated fuel samples were aged in the dark for 12 weeks at 110 F. in 5 gallon metal cans.
• a thermally stabilized jet fuel consisting essentially of a liquid hydrocarbon jet fuel, and, as thermal stabilizers thereof, from about 1 to 10 lbs. per bbls. of said fuel of an N,N-disalicylidene aliphatic polyamine and from about 5 to 50 lbs. per 1000 bbls.
• a C -C monoamine taken from the group consisting of (a) a tertiary alkyl primary amine, (b) a secondary amine whose two organic substituents are monovalent saturated hydrocarbon radicals, (c) a tertiary amine whose three organic substituents are monovalent saturated hydrocarbon radicals, and, (2) mixed monoand dialkyl phosphates whose alkyl groups contain from 8 to 18 carbon atoms.
• the amine salt additive is a C3-C21 tertiary alkyl primary amine salt of an acid alkyl phosphate, the alkyl groups being branched chain alkyl groups having from 8 to 18 carbon atoms.
• An improved method of operating a jet engine wherein the jet fuel to be combusted is in heat-exchange relationship with the hot engine which comprises the step of combusting a liquid hydrocarbon jet fuel stabilized against thermal deterioration by introducing into said fuel, before the fuel enters into said heat-exchange relationship, an N.N-disalicylidene aliphatic polyamine, and, a jet fuelsoluble salt of (1) a C5-C24 monoamine taken from the group consisting of (a) a tertiary alkyl primary amine,

Landscapes

• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Liquid Carbonaceous Fuels (AREA)
• Solid Fuels And Fuel-Associated Substances (AREA)

Priority Applications (3)

Applications Claiming Priority (1)

Publications (1)

Family

ID=24993476

Family Applications (1)

Country Status (3)

Cited By (2)

Families Citing this family (1)

Citations (5)

• 1958
  • 1958-06-26 US US744643A patent/US3032973A/en not_active Expired - Lifetime
• 1959
  • 1959-06-25 GB GB21819/59A patent/GB850914A/en not_active Expired
  • 1959-06-26 FR FR798706A patent/FR1237334A/fr not_active Expired

Patent Citations (5)

Also Published As

Similar Documents