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
  • C10L1/143—Organic compounds mixtures of organic macromolecular compounds with organic non-macromolecular 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
• • 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
  • C10L1/16—Hydrocarbons
  • C10L1/1616—Hydrocarbons fractions, e.g. lubricants, solvents, naphta, bitumen, tars, terpentine
• • 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
  • C10L1/18—Organic compounds containing oxygen
  • C10L1/192—Macromolecular compounds
  • C10L1/195—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • C10L1/196—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds derived from monomers containing a carbon-to-carbon unsaturated bond and a carboxyl group or salts, anhydrides or esters thereof homo- or copolymers of compounds having one or more unsaturated aliphatic radicals each having one carbon bond to carbon double bond, and at least one being terminated by a carboxyl radical or of salts, anhydrides or esters thereof
  • C10L1/1963—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds derived from monomers containing a carbon-to-carbon unsaturated bond and a carboxyl group or salts, anhydrides or esters thereof homo- or copolymers of compounds having one or more unsaturated aliphatic radicals each having one carbon bond to carbon double bond, and at least one being terminated by a carboxyl radical or of salts, anhydrides or esters thereof mono-carboxylic
• • 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
  • C10L1/18—Organic compounds containing oxygen
  • C10L1/192—Macromolecular compounds
  • C10L1/195—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • C10L1/196—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds derived from monomers containing a carbon-to-carbon unsaturated bond and a carboxyl group or salts, anhydrides or esters thereof homo- or copolymers of compounds having one or more unsaturated aliphatic radicals each having one carbon bond to carbon double bond, and at least one being terminated by a carboxyl radical or of salts, anhydrides or esters thereof
  • C10L1/1966—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds derived from monomers containing a carbon-to-carbon unsaturated bond and a carboxyl group or salts, anhydrides or esters thereof homo- or copolymers of compounds having one or more unsaturated aliphatic radicals each having one carbon bond to carbon double bond, and at least one being terminated by a carboxyl radical or of salts, anhydrides or esters thereof poly-carboxylic
• • 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
  • C10L1/18—Organic compounds containing oxygen
  • C10L1/192—Macromolecular compounds
  • C10L1/195—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • C10L1/197—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds derived from monomers containing a carbon-to-carbon unsaturated bond and an acyloxy group of a saturated carboxylic or carbonic acid
  • C10L1/1973—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds derived from monomers containing a carbon-to-carbon unsaturated bond and an acyloxy group of a saturated carboxylic or carbonic acid mono-carboxylic

Definitions

• Heating oils and other middle distillate petroleum fuels e.g., Diesel fuels
• Diesel fuels contain normal paraffin hydrocarbon waxes which, at low temperatures, tend to precipitate in large crystals in such a way as to set up a gel structure which causes the fuel to lose its fluidity.
• the lowest temperature at which the fuelwill still flow is generally known as the pour point.
• the pour point When-the fuel temperature reaches or goes below the pour point and the fuel is no longer freely flowable, difficulty arises in transporting the fuel through flow lines and pumps, as for example when attempting to transfer the fuel from one storage vessel to another by gravity or under pump pressure or when attempting to feed the fuel to a burner.
• copolymers of ethylene and other monomers such as vinyl'esters, acrylate estersor methacrylate esters, and the like to lower the pour point and improve the flowability of middle distillate fuels at low temperature is well known in the art. See
• the low temperature flow properties of the petroleum middle distillate fuel oil can be improved by incorporating into the fuel oil a small concentration of an ethylene copolymer type pour point depressant and a small concentration of an essentially saturated hydrocarbon fraction that is substantially free of normal paraffinic hydrocarbons, the hydrocarbon fraction having a number average molecular weight in the range of about 600 to about 3,000.
• the ethylene copolymer is further characterized by being a random copolymer of from 3 to moles of ethylene and 1 mole of an unsaturated ester, wherein the copolymer has less than 6 methyl-terminating side branches per 100 methylene groups, and the copolymer has a number average molecular weight of about 1000 to 50,000. More specifically, there are added to a waxy middle distillate petroleum fuel, from about 0.1 to about 3 weight percent, preferably about 0.2 to 1 weight percent, of the said high molecular weight hydrocarbon fraction, together with from about 0.005 to about 1 weight percent, generally about 0.0l to 0.1 weight percent, of ,the ethylene copolymer pour depressant.
• the weight ratios of the two types of additives can vary from equal parts to as little as 1/25th as much of the ethylene copolymer pour depressant as the high molecular weight hydrocarbon fraction.
• the distillate fuel oil can comprisestraight run or .virgin gas'oil or cracked gas oil or a blend in any proportion of straight run and thermally and/or catalytically cracked distillates.
• the most common petroleum middle distillate fuels are kerosene, diesel fuels, jet fuels and heating oils. Since jet fuels are normallyrefined to very low pour points, there will be generally no need to apply the present invention to such fuels.
• the low temperature flow problem is most usually encountered with diesel fuels and with heating oils.
• a representative heating oil specification calls for a 10 percent distillation point no higher than about 440F., a 50 percent point no higher than about 5 20F., and a percent point of at least 540F. and no higher than about 640F. to 650F., although some specifications set the 90 percent point as high as 675F.
• Heating oils are preferably made of a blend of virgin distillate, e.
• a representative specification for. a diesel fuel includes a minimum flash point of F. and a 90 percent distillation point between 540F. and 640F.
• the copolymer flow-improving additive that is used in this invention is a copolymer formed from about 3 to about 40 molar proportions of ethylene, and one normal paraffmic hydrocarbons and having a number average molecular weight within the range of about 600 to 3,000, when added to a middle distillate petroleum fuel oil in a concentration of about 0.01 to about 3 weight percent, will depress the pour point of the fuel oil to some extent and will'also improve the low temperature flowability of the said petroleum fuel oil. Itis mole of at least one second unsaturated monomer.
• the polymer is oil-soluble and is characterized by having less than six methyl terminating side branches on the polyethylene backbone per 100 methylene groups of the said backbone.
• Such polymers are preparedby free radical catalysis in a solvent at temperatures of less than C. in order to minimize ethylene branching,
• R is hydrogen or methyl
• R is a OOCR or COOR group wherein R is hydrogen or a C to C preferably a C to C straight or branched chain alkyl group
• R is hydrogen or COOR.
• R and R when R and R are hydrogen and R is OOCR., includes vinyl alcohol esters of C to C monocarboxylic acids, preferably C to C monocarboxylic acids. Examples of such esters include vinylacetate, vinyl isobutyrate, vinyl laurate, vinyl myristate, vinyl palmitate, etc.
• esters include methyl acrylate, methyl methacrylate, lauryl acrylate, palmityl alcohol ester of alpha-methylacrylic acid, C Oxo alcohol esters of methacrylic acid, etc.
• Examples of monomers where R is hydrogen and R and R are COOR., groups, include monoand diesters of unsaturated dicarboxylic acids such as: mono-C Oxo fumarate, di-C Oxo fumarate, diisopropyl maleate; di-lauryl fumarate, ethyl methyl fumarate; etc.
• the Oxo alcohols used in preparing the esters mentioned above are isomeric mixtures of branched chain aliphatic, primary alcohols prepeared from olefms, such as polymers and copolymers of C to C, monoolefins, reacted with carbon monoxide and hydrogen in the presence of a cobalt-containing catalyst such as cobalt carbonyl, at temperatures of about 300 to 400F., under pressures of about 1000 to 3000 psi,.to form a1- dehydes.
• the resulting aldehyde product is then hydrogenated to form the 0x0 alcohol, the latter being recovered by distillation from the hydrogenated product.
• ethylene will be used per mole of other monomer, which other monomer is preferably an ester as hereinbefore defined, or a mixture of about 30 to 99 rnole percent ester and 70 to 1 mole percent ofa C to C preferably C to C branched or straight chain alpha monoolefin.
• olefins include propylene, n-octenel,n-decene-1, etc.
• the polymerizations can be carried out as follows: Solvent and a portion of the unsaturated ester, e.g., 0-50, preferably to 30 weight percent, of the total amount of unsaturated ester used in the batch, are charged to a stainless steel pressure vessel which is equipped with a stirrer. The temperature of the pressure vessel is then brought to the desired reaction temperature and pressured to the desired pressure with ethylene. Then catalyst, preferably dissolved in solvent so that it can be pumped, and additional amounts of unsaturated ester are added to the vessel continuously, or at least periodically, during the reaction time, which continuous addition gives a more homogeneous copolymer product as compared to adding all the unsaturated ester at the beginning of the reaction.
• the solvent can be any non-reactive organic solvent for furnishing a liquid phase reaction which will not poison the catalyst or otherwise interfere with the reaction, and preferably is a hydrocarbon solvent such as benzene, hexane, cyclohexane, dioxane, or t'ert-butyl alcohol.
• the temperature used'during the reaction will be in the range of to 130 C., preferably to 125 C.
• Preferred free radical catalysts or initiators are those which decompose rather rapidly at the prior noted reaction temperatures, for example, those that have a half-life of about an houror less at 130C. preferably.
• this will include the acyl peroxides of C to C branched or unbranched, carboxylic acids such as di-acetyl peroxide (half-life of 1.1 hours at C.); dipropionyl peroxide (half-life of 0.7 hour at 85C.); dipelargonyl peroxide (half-life of 0.25 hour at 80C.); di-lauroyl peroxide (half-life of 0.1 hour at C.), etc.
• the lower peroxides such as di-acetyl and dipropionyl' peroxide are less preferred because they are shock sensitive, and as a result the higher peroxides such as di-lauroyl peroxide are especially preferred.
• the short half-life catalysts are less preferred because they are shock sensitive, and as a result the higher peroxides such as di-lauroyl peroxide are especially preferred.
• azo free radical initiators such as azodiisobutyronitrile (half-life, 0.12 hour at 100C.); azobis-Z- methylheptonitrile and azobis-2-methyl-valeronitrile.
• azodiisobutyronitrile half-life, 0.12 hour at 100C.
• azobis-Z- methylheptonitrile azobis-2-methyl-valeronitrile.
• 'di-tert. butyl peroxide which has been used extensively in the prior art, has a half-life of about 180 hours at 100C. and a half-life of about 7 hours at C., and does not produce the desired low degree of branching.
• a copolymer of 6 to 6.5 moles of ethylene per mole of vinyl acetate has an average of about 3.5 methyl-terminating side branches on the polyethylene backbone per 100 methylene groups of the'backbone if the copolymer is prepared at 105C. and900-950 psig pressure using lauroyl peroxide catalyst or initiator, but has an average of about 10 to 1 1 such branches if prepared at C. and
• the pressures employed can range between $00 and 30,000 psig. However, relatively moderate pressures of 700 to about 3,000 psig will generally suffice with vinyl esters such as vinyl acetate. In the case of esters having a lower reactivity to ethylene, such as methyl methacrylate, then somewhat higher pressures, such as 3,000 to 10,000 psi have been found to give more optimum results than lower pressures. ln general, the pressure should be at least sufficient to maintain a liquid phase medium under the reaction conditions, and to maintainthe desired concentration of ethylene in solution in the solvent. i
• the time of reaction will depend upon, and is interrelated to, the temperature of the reaction, the choice of catalyst, and the pressure employed. In general, however, 05 to 10, usually 2 to 5 hours will complete the desired reaction.
• fractions of essentially saturated hydrocarbons that are used in accordance with thepresent invention in conjunction with the copolymer pour point depressants are generally amorphous solid materials having melting points within the range of about 80 to 140F. and having number average molecular weights within the range of about 600 to about 3,000. This molecular weight range is above the highest molecular weight of any hydrocarbons that are naturally present in the fuel oil.
• An amorphous hydrocarbon fraction that is useful in accordance with this invention can be obtained by deasphalting a residual petroleum fraction and then adding a solvent such as propane to the deasphalted residuum, lowering the temperature of the solvent-diluted residuum, and recovering the desired solid or semisolid amorphous material by precipitation at a low temperature followed by filtration.
• the residual oil fractions from which the desired hydrocarbons are obtained will have viscosities of at least 125 SUS at 210F.
• lecular weight amorphous fraction can be obtained which has only a trace of normal paraffins, about 5 percent of isoparaffins, about 73 percent of cycloparaffins and about 22 percent of aromatic hydrocarbons. In other instances it is necessary to treat the high molecular weight fraction in some manner to reduce its content of normal paraffins. Removal of normal paraffins from an amorphous hydrocarbon mixture can be effected by complexing with urea, as will be illustrated hereinafter in one of the examples. Solvent extraction procedures can also be used, but in many instances they are not as effective as complexing techniques.
• amorphous hydrocarbon mixture can be dissolved in a ketone, e.g., methyl ethyl ketone, at its boiling point and then when the solution is cooled to room temperature the normal paraffins will be predominantly precipitated and the resultant supernatant solution will give a mixture containing some normal paraffins but predominating in cycloparaffins and isoparaffins.
• a ketone e.g., methyl ethyl ketone
• Vacuum distillation can also be used for the removal of normal paraffin hydrocarbons from a high molecular weight paraffinic fraction, but such a procedure requires a very high vacuum, i.e., less than 5 mm Hg. absolute pressure, preferably apressure below 3 mm Hg,
• absolute e.g., 2 mm. or 120 microns. If the pressure used is 5 mm or higher, the necessary temperature for the distillation is high enough to cause cracking of the constituents, which is undesirable.
• EXAMPLE -1 Fuel oil blends-were prepared using a middle distillate fuel oil consisting of volume percent of cracked distillates having a final boiling point of 660F. and 15 volume percent of heavy virgin naphtha, the fuel oil having a cloud point of +l2F. and a pour point of 5F. To separate portions of this fuel oil there were added various percentage concentrations of the amorphous solidhydrocarbon fraction, essentially free of normal paraffin hydrocarbons, described above. To. other portions of the fuel oil there were added various concentrations of the copolymer of ethylene and vinyl acetate described above. To still other portions of the fuel oil there wereadded both the solid hydrocarbon fraction and the pour point depressant. Each of the resulting fuel oil blends was subjected to a low temperature filterability test which is run as follows:
• a 200 milliliter sample of the oil is cooled at a controlled rate of 2F. per hour until a temperature of 0F. is reached, this being the temperature at which the flow test is conducted.
• the oil is then filtered through a US. 40 mesh screen at the test temperature, and the volume percentage of oil that passes through the screen at the end of 25 seconds is then measured. If at least percent of the oil has gone through the'screen in no more than 25 seconds, the oil is considered to pass the test.
• Table I The composition of each blend and the low temperature filterability test results are given in Table I, which follows.
• the copolymer flow improver that was used in this example was a copolymer of ethylene and vinyl acetate having a mole ratio of ethylene to vinyl acetate of about 4.2 and having an average molecular weight as determined by vapor phase osmometry of about 1740.
• a typical preparation of this pour depressant is as follows:
• a three-liter stirred autoclave was charged with 850 ml. of benzene as solvent and 40 ml. of vinyl acetate.
• the vapor space of the autoclave was first purged with a stream of nitrogen and then with a stream of ethylene.
• the autoclave was then heated to 180F. while ethylene was pressured into the autoclave until the pressure was raised to 750 psig. Then, while maintaining a temperature of 180F. and said 750 psig pressure, 100 mL/hour of vinyl acetate and 160 ml./hour of solution consisting of 12 parts by weight of di-lauroyl peroxide dissolved in'88 parts by weight of benzene, were continuously pumped into the autoclave at an even rate.
• EXAMPLE 2 A copolymer of ethylene, vinyl acetate, and di-C Oxo alcohol fumarate ester is prepared at 900 psig and dure as in the preparation of the vinyl acetate and ethylene copolymer of Example 1.
• the initial charge is 670 ml. of benzene and 32 ml. of vinyl acetate.
• a mixture of weight percent of vinyl acetate and 20 weight percent of fumarate esters is injected at the rate of 80 ml. per hour for 145 minutes along with 64 ml. per hour of a solution of 23 weight percent lauroyl peroxide in 77 weight percent of benzene for a total of 155 minutes.
• a yield of 200 grams of polymer is obtained.
• Example 1 percent solution of the polymer in kerosene has a kinematic viscosity at F. of 42 centistokes.
• the base fuel oil of Example 1 is improved in low temperature properties by adding thereto 0.02 weight percent of the terpolymer and 0.2 weight percent of the amorphous solid, substantially normal-paraffinhydrocarbon-free fraction used in Example 1.
• R is selected from the group consisting of hydrogen and methyl radicals
• R is selected from the group consisting of OOCR and COOR. groups.
• c. R is selected from the group consisting of hydrogen and -COOR and
• i d. R is selected from the group consisting of hydrogen and C, C alkyl groups.
• Fuel composition as defined by claim 1 wherein the weight ratio of said substantially normal-paraffinhydrocarbon-free hydrocarbon fraction to said random copolymer is from about 1:1 to about 25:1.

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)

Applications Claiming Priority (1)

Publications (1)

Family

ID=25197545

Family Applications (1)

Country Status (2)

Cited By (52)

Citations (10)

• 1969
  • 1969-03-17 US US00807966A patent/US3790359A/en not_active Expired - Lifetime
• 1970
  • 1970-05-01 GB GB2114970*A patent/GB1301933A/en not_active Expired

Patent Citations (10)

Also Published As

Similar Documents