Title of Invention

A BIODEGRADABLE HYDRAULIC FLUID COMPOSITION

Abstract

The present invention provides a biodegradable hydraulic fluid composition. This biodegradable hydraulic fluid composition mainly contains modified non-edible vegetable oils such as karanja (Pongamia Glabra) oil, neem (Mellia Azadirachta) oil, ricebran (Oryza Sativa) oil, mahua (Madhuca Indica) oil, castor (Ricinus Communis) oil, acetylated castor, linseed (Flax-Linium Usitatissimum) oil and/or other vegetable oils or mixture thereof. In addition to chemically modified non-edible vegetable oils, the composition also contains an antioxidant, an extreme pressure additive, an antifoaming agent, a pour point depressant, a corrosion inhibitor and a detergent-dispersant additive, according to which it produce lower amount of pollution. The product of this invention has utility as a general purpose hydraulic fluid in vacuum pumps and stationary equipment.

Full Text

FIELD OF THE INVENTION The present invention relates to a biodegradable hydraulic fluid composition. This invention particularly relates to significant-biodegradable hydraulic fluid composition that mainly contains modified non-edible vegetable oils. In addition to chemically modified non-edible vegetable oils, the composition also contains an antioxidant, an extreme pressure additive, an antifoaming agent, a pour point depressant, a corrosion inhibitor and a detergent-dispersant additive, according to which it produce lower amount of pollution. The product of this invention has utility as a general purpose (mineral oil type) hydraulic fluid. BACKGROUND OF THE INVENTION Hydraulic fluid is an industrial lubricant used in many applications, from gear pumps to axial piston pumps to heavy-duty farm and industrial equipment. All hydraulic fluids should prevent components from excessive wear and maintenance costs even under extreme temperatures. The deterioration can result from a variety of factors. Rust is one common problem that plagues small parts in engines, transmissions, and hydraulics systems. This problem often arises from the presence of excess water vapor in the system. Oxidation and foam build up is other problems that build up over time and affect the performance of hydraulics systems. For optimal functioning, a hydraulic fluid must be relatively incompressible and must flow readily. In addition, it should provided adequate lubricity for moving parts, stability under anticipated conditions of use, compatibility with materials used to construct the hydraulic system, and the fluids should have the ability to protect system components against chemical reaction with materials which may enter the system. Finally, they should have a minimal impact on the environment. The hydraulic fluid serving as the power transmission medium in a hydraulic system. The most commonly used fluids are petroleum oils, synthetic lubricants, oil-water emulsion, and water-glycol mixtures. The principal requirements of a hydraulic fluid are proper viscosity high viscosity index, anti-wear protection, good oxidation stability, adequate pour point, good de-emulsibility, rust inhibition, resistance to foaming, and compatibility with seal materials. Anti-wear oils are frequently used in compact, high-pressure, and high-capacity pumps that require extra lubrication protection. Certain synthetic lubricants and water-containing fluids are used where fire resistance is needed. Synthetic lubricants also are used in extreme-temperature conditions. Only slight change in volume during usage, adequate oxidation resistance, for some cases of application adequate de-emulsification capacity, adequate shear stability, if polymer viscosity index improvers are used viscosity-temperature behavior, so that oil changes due to summer and winter operation become redundant, adequately low viscosity-temperature behavior, and minimal characteristics changes of standard elastomers are desirable. Now, pollution and environmental aspects of various products have become important issues. The uncontrolled loss of lubricants can endanger environment by coming into contact directly with the nature (organisms, soil, live water etc.) as a consequence of leakage, throw off, emissions, spillage or careless disposal. Great efforts have been made during the last 25 years by several countries and major industries to develop and find more and more environment friendly - nontoxic products and technologies which have a less negative impact on our precious environment. The petroleum based lubricating oils are hydrocarbons consisting of naphthenes, paraffins, aromatics, polynuclear aromatics and unsaturates. Various additives, which are primarily chemicals of defined composition or structure, are added to the lube oils to improve the physico-chemical properties and performance. Petroleum based lube oils, generally suffer from many disadvantages such as high toxicity to the environment, poor biodegradability and inconsistent characteristics with change in crude oil composition. The other types of lubricants known as synthetic lubricants are deigned for use in extreme conditions of temperature, pressure, radiation or chemical and have excellent lubricity and thermal stability. The synthetic lubricants are relatively costly, also toxic to environment and are may not be readily biodegradable. Certain types of mono-esters from non-edible vegetable oils are useful to generate reduced pollution after use in hydraulic equipments, completely biodegradable, can be used safely, economical than synthetic esters, compatible to mineral oil, are capable of providing the desirable lubricant properties such as good boundary layer lubrication, high viscosity index, high flash point and low volatility. Low thermo-oxidative stability of vegetable oils can be improved with the help of a suitable chemical modification and additive. Vegetable oil that is long chain fatty acid triester of glycerol possesses most of the desirable lubricant properties such as high viscosity index, high flash point, low volatility and good boundary lubrication. As per fatty acid typical composition of vegetable oils, it contains unsaturated acids such as oleic C18:1 as a major component. It is understood that some of the carbon chain lengths of the carboxylic acids and/or esters discussed here by average carbon numbers. This reflects the fact that some of the carboxylic acids and/or esters are derived from naturally occurring materials and therefore contain a mixture of compounds the major component of which is the stated compound. Non-edible vegetable oil, which are found in abundance in India are, (1) Neem - Mellia Azadirachta in the family Meliaceae, (2) Karanja - Pongamia glabra in the family Leguminaceae, (3) Ricebran - Oryza sativa in the family Graminaceae, (4) Mahua- Madhuca Indica & Madhuca Longifolia, (5) Castor - Ricinus communis in the family Euphorbiaceae (spurge), (6) Linseed - Flax oil plant Linium usitatissimum (Linacae), (7) Other similar vegetable oil or their mixture. Reference may be made to United States Patent 5,360,565 Junga, November 1, 1994 Petro-Lube, Inc. (Whitemore Lake, Ml) Hydraulic fluid. An improved anti-wear, high-pressure hydraulic fluid which contains essentially no zinc or phosphorous is described. The hydraulic fluid protects against corrosion and oxidation as well as provides anti-wear, anti-weld, and demulsibility properties. This improved hydraulic fluid contains (1) petroleum hydrocarbon oil; (2) esters of dibasic and monobasic acids; (3) butylated phenol; (4) phenol; (5) sulfurized fatty oil; (6) fatty acid; and (7) sulfur scavenger. This hydraulic fluid has a reduced tendency towards sludge formation and has, therefore, an increased lifetime, (mineral oils was used) Reference may be made to US Patent 6,300,292 Konishi , et al. October 9, 2001 Nippon Mitsubishi Oil Corporation (Tokyo, JP) Hydraulic fluid composition. A hydraulic fluid composition which is excellent in oxidative stability, lubricating properties and biodegradability; comprising vegetable oil as base oil, and one phenol antioxidant, an amine antioxidant and a zinc dithiophosphate antioxidant. (edible vegetable oils are used) Reference may be made to US Patent 6,436,883, Nieh, August 20, 2002, Huntsman Petrochemical Corporation (Austin, TX) Hydraulic and gear lubricants. Provided herein are functional fluid compositions useful in hydraulic fluid and gear oil formulations. The formulations according to the invention include a predominant amount of at least one polyoxyalkylene glycol derived from the addition polymerization of an alcohol in the presence of an alkylene oxide mixture, which contains a substantial amount of ethylene oxide. Fluids according to the invention exhibit suitable lubricity and stability characteristics and are generally water soluble to a degree sufficient to preclude formation of a sheen on the surface of a body of water into which a fluid according to the invention is brought into contact, (polyethylene glycol was used) Reference may be made to US Patent 5,366,658, Hoppe, et al., November 22, 1994, Huls Aktiengesellschaft (Marl, DE) Use of polymethylalkanes as biodegradable base oils in lubricants and functional fluids The invention relates to the use of polymethylalkanes having terminal methyl groups and methylene and ethylidene groups in which the total number of C atoms n+2 m+2 is 20 to 100 and the ratio of the methyl and methylene groups to the ethylidene groups is 3 to 20:1 and the ethylidene groups are always separated by at least one methylene group, as biodegradable base oils for lubricants and functional fluids. Suitable polymethylalkanes are obtained by oligomerization of .alpha.,.omega.-diolefins, for example in particular according to P 41 19 332.6, or by pyrolysis of ethene/propane copolymers and subsequent hydrogenation in each case. The polymethylalkanes can be combined with conventional additives and other degradable or non-degradable base oils, (polymethyl alkanes was used) Reference may be made to U.S. Pat. No. 4,783,274 (Jokinen et al., Nov. 8, 1988) Concerned with an anhydrous oily lubricant, which; is based on vegetable oils, which is substituted for mineral lubricant oils, and which, as its main component, contains triglycerides that are esters of saturated and/or unsaturated straight-chained C.sub.10 to C.sub.22 fatty acids and glycerol. The lubricant is characterized in that it contains at least 70 percent by weight of a triglyceride whose iodine number is at least 50 and no more than 125 and whose viscosity index is at least 190. As its basic component, instead of or along with the said triglyceride, the lubricant oil may also contain a polymer prepared by hot-polymerization out of the said triglyceride or out of a corresponding triglyceride. As additives, the lubricant oil may contain solvents, fatty acid derivatives, in particular their metal salts, organic or inorganic, natural or synthetic polymers, and customary additives for lubricants, (edible vegetable oils with polymers are used) Reference may be made to U.S. Pat. No. 5,538,654 (Lawate et al., Jul. 23, 1996) Describes a food grade lubricant composition, which is useful as hydraulic fluid, gear oil, and compressor, oil for equipment in the food service industry. This composition .comprises (A) a major amount of a genetically modified vegetable oil and (B) a minor amount of a performance additive. In other embodiments the composition contains either (C) a phosphorus compound or (D) a non-genetically modified vegetable oil. (edible vegetable oils and genetically modified oils are used) Reference may be made to U.S. Pat. No. 5,580,482 (Chassan et al., Dec. 3, 1996) A lubricant composition stabilized against the deleterious effects of heat and oxygen said composition comprising a triglyceride oil or an oil which is an ester wherein unsaturation is present in either the alcohol moiety or the acid moiety and an effective stabilizing amount of either an N,N-disubstituted aminomethyl-1,2,4-triazole or an N,N-disubstituted aminomethylbenzotriazole and a higher alkyl substituted amide of dodecylene succinic acid, (edible vegetable oil with an additive was used) Reference may be made to U.S. Pat. No. 5,888,947 (Lambert et al., Mar. 30, 1999) A composition that has three main components: a base oil, an oil source containing hydroxy fatty acids and an oil source containing vegetable or animal waxes. The base oil used in the reference needs to consist of primarily triglycerols (triglycerides) and mono- and diglycerols (glycerides) and free fatty acids. The composition further consists of vegetable oils where the glycerols contain hydroxy fatty acids, preferably making up 5% to 20% of the oil. A third major component is waxes composing 5% to 10% of the oil additives by volume. Additional synthetic mimics or natural products derived from animal or vegetable compounds may be added up to 5% of the compositional volume. ( glycol fatty esters and fats are used) In the prior art for producing hydraulic fluids, generally, mineral oils, mineral oil with synthetic fluids, complex ester of fatty acids or their blends were used. The focus has been on the use of such oil base to enhance the performance. In view of the growing concern about the environment, there is a need for biodegradable hydraulic fluids, which are derived from renewable resources, reduce pollution, readily miscible with mineral oil and synthetics. These objectives must be met, while simultaneously satisfying stringent performance standards, e.g., good lubricity, load carrying, stability and anti-corrosion. OBJECTIVES OF THE INVENTION The main object of the present invention is to provide a biodegradable hydraulic fluid composition based on mono-esters of non-edible vegetable oils such as Neem, Karanja, Rice bran, Mahua, Castor, Linseed and other similar oils. Yet another object of the present invention is to provide excellent miscibility of formulated hydraulic fluid with mineral and synthetic oil in all proportions. SUMMARY OF THE INVENTION Accordingly the present invention provides a biodegradable hydraulic fluid composition comprising: i. mono-esters of non-edible vegetable oil fatty acid in the range of 97.65 -99.888 wt%, ii. anti-oxidant in the range of 0.006-0.05% by weight, iii. extreme pressure additives in the range of 0.006-0.05% by weight, iv. anti-foaming agent in the range of 0.01 to 1.0% by weight, v. pour point depressant in the range of 0.01 to 1.0% by weight, vi. corrosion inhibitor in the range of 0.03 to 0.1% by weight, vii. detergent -dispersant in the range of 0.05-0.15 % by weight. In an embodiment of the present invention biodegradable hydraulic fluid composition further comprising: i) mono-esters of non-edible vegetable oil fatty acid used is selected from the group consisting of 2ethyl-1-hexyl(10-epoxy)9 octadecenoic ester of formula [C8Hi7(>O) CH=CHC7H14COOCHCH2(C2H5)C5H1o], 2ethyl-1-hexyl (10-toluene) 9 octa decenoic ester of formula C8H17(C6H4CH3- )CH=CHC7H14COOCHCH2 (C2H5)C5Hio ] , 2ethyl-1-hexyl-9 octadecenoic ester of formula C8H17CH =CH C7COOCHCH2(C2H5)C5H] and a mixture thereof in the range of: 97.65-99.888 by weight, ii) anti-oxidant in the range of 0.006-0.05% by weight, iii) extreme pressure additives in the range of 0.006-0.05% by weight, iv) anti-foaming agent in the range of 0.01 to 1.0% by weight, v) pour point depressant in the range of 0.01 to 1.0% by weight, vi) corrosion inhibitor in the range of 0.03 to 0.1% by weight, vii) detergent-dispersant in the range of 0.05-0.15 % by weight. In an embodiment of the present invention, the monoester of non-edible vegetable oil fatty acid used is a monoester of fatty acid with C1 to C16 preferably C7 to C12 primary alcohol. In another embodiment of the present invention, the mono-ester of vegetable oil fatty acid used is selected from the group consisting of simple ester, partially hydrogenated ester, epoxy ester, aryl alkyl ester of fatty acids and a mixture thereof. In yet another embodiment of the present invention, the monoester of non-edible vegetable oil fatty acid used is preferably selected from the group consisting of 2ethyl-1-hexyl(10-epoxy)9 octadecenoic ester of formula [C8Hi7(>O) CH=CHC7Hi4COOCHCH2(C2H5)C5H10], 2ethyl-1-hexyl (10-toluene) 9 octa decenoic ester of formula C8Hi7(C6H4CH3-)CH=CHC7Hi4COOCHCH2 (C2H5)C5Hio ] , 2ethyl-1-hexyl-9 octadecenoic ester of formula C8H17CH =CH C7H14COOCHCH2(C2H5)C5Hio] and a mixture thereof. In yet another embodiment of the present invention, the non-edible vegetable oil triglyceride fatty acid used is selected from the group consisting of C18:1, C18:2, C18:3, having the mono-unsaturation character in the range of about 50 to 70 weight percent. In yet another embodiment of the present invention, the non-edible vegetable oil used is selected from the group consisting of karanja (Pongamia glabra) oil, neem (Mellia azadirachta) oil, ricebran (Oryza sativa) oil, mahua (Madhuca indica) oil, castor (Ricinus communis) oil, acetylated castor, linseed (flax-L/n/t/m usitatissimum) oil, other vegetable oils and a mixture thereof. In yet another embodiment of the present invention, the non-edible vegetable oil used is selected from the group consisting of karanja, ricebran, mahua, neem and a mixture thereof. In yet another embodiment of the present invention, the mono-esters of fatty acids used as base stock have viscosity, cst, of 50 - 82 at 40°C and. a flash point 200-240°C (Cleveland Open Cup). In yet another embodiment of the present invention, the anti-oxidant used is selected from the group consisting of hindered phenol, alkyl amine, amino phenol and tetrazole. In yet another embodiment of the present invention, the anti-oxidant used is selected from the group consisting of2,4,6-tri-tert-butylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-t-butyl-4-methylphenol, bicyclic hindered amines, diphenylamines, dinaphthylamines, 4-methyl-2,6-di-(t-butyl) phenol, methyl hydroxy hydro cinnamide, alkylated 5-amino tetrazole and di-ter. Butyl p-amino phenol. In yet another embodiment of the present invention, the extreme pressure additive is selected from the group consisting of sulfurized neem oil, sulfurized mahua oil, dibenzyl disulphide, suphurized pentadecyl phenol, thiophosphoro luryl oleate, molybdenum salt of thiophosphoro luryl oleate, zinc dialkyl dithio phosphate, dibenzyl diselenate, selenophosphoro luryl oleate, selenophosphoro pentadecyl phenol and molybdenum thiophosphoro pentadecyl phenol. In yet another embodiment of the present invention, the anti-foaming agent used is selected from the group consisting of silicone oil, polyvinyl alcohol and polyethers. In yet another embodiment of the present invention, the pour point depressants used is selected from the group consisting of diethylhexyl adipate, polymethacrylate and polyvinylacrylate. In yet another embodiment of the present invention, the anti-corrosion additive used is selected from the group consisting of octyl 1H benzotriazole, ditertiary butylated 1 H-Benzotriazole, propyl gallate, polyoxyalkylene polyols, octadecyl amines, nonyl phenol ethoxylates, calcium phenolates of hydrogenated pentadecyl phenol, and magnesium alkyl benzene sulfonates. In still another embodiment of the present invention, the detergent-dispersant used is selected from the group consisting of amino alkyl benzene sulfonate, calcium alkyl benzene sulfonate, sodium alkyl benzene sulfonate, propylene teramer succinimide of pentaethylene hexamine and octyl phosphonates. In still another embodiment the biodegradable hydraulic fluid composition obtained has the following characteristics: i. kinematic viscosity at about 40°C is in the range of 50-82 cst, ii. viscosity index is ranging between 200-270, iii. oxidation stability is Pass (IP 48/97) (1 % increase in viscosity & TAN), iv. rotary bomb oxidation test (ROBOT) at 95°C is between 150-200 min, v. flash point is ranging between 210-240°C, vi. pour point is ranging between (-)9 - (-)25°C, vii. ash sulfated % is xii. lubricity(mm)- Friction coefficient-0.105-0.115, xiii. lubricity (mm)- wear scar dia- 0.303 - 0.305, xiv. panel cocking test (20 mg max) Pass, xv. biodegradability is between 90-100%. DETAILED DESCRIPTION OF THE INVENTION The compositions are significantly biodegradable and ecofriendly from a renewable source exhibit excellent miscibility with mineral and synthetic oil in all proportions. The main advantages of the present invention are, reduces use of petroleum, beneficial to farmers, and safer to handle due to higher flash point of 200-240°C. The present lubricant would be particularly suited for mineral type VG46 to VG 68 general purpose hydraulic fluid and exhibit excellent miscibility with mineral and synthetic oil in all proportions. The temperature used for blending all the components to make the homogenous composition at the moderate temperature of 60°C at which no chemical reaction occur, but all constituents get blended to obtain the desired composition having the synergistic effect reflecting a different characteristics as the individual constituents as'described in the examples. The present invention provides a hydraulic fluid from non-edible vegetable oil, which is superior in performance, particularly in pour point, viscosity index and toxicity, as compared below, Comparison of properties of hydraulic fluid EXAMPLE 1 PURIFICATION OF EPOXY ESTER: Simple epoxy ester of neem oil fatty acid and ethyl hexanol [major portion is of 2Ethyl-1-hexyl,(10-epoxy) 9,octadecenoic ester, formula- CsHOJCCHCrHuCOOCHChCaHs) C5H10] was purified by known method by dissolving it in a mixed solvent containing heptane and ethanol. The mixture of oil and solvent was cooled to 12-15°C and the temperature maintained for 5 to 7 h. The upper layer containing oil and solvent was passed through Indian Multani clay column. Solvent was recovered to get purified oil. EXAMPLE 2 PURIFICATION OF EPOXY ESTER: Epoxy ester of karanja oil fatty acid and ethyl hexanol [major portion is of 2Ethyl-1-hexyl,(10-epoxy) 9,octadecenoic ester formula-C8H17(>0)CH=CHC7Hi4COOCHCH2(C2H5) C5H10] was purified by known method by dissolving it in a mixed solvent containing heptane and ethanol. The mixture of oil and solvent was cooled to 12-15°C and the temperature maintained for 5 to 7 h. The upper layer containing oil and solvent was passed through Indian Multani clay column. Solvent was recovered to get purified oil. EXAMPLE 3 PURIFICATION OF ALKYL ESTER: Alkyl (Toluene substituted) ester of Mahua oil fatty acid and ethyl hexanol [major portion is of 2Ethyl-1-hexyl, (10-toluene) 9,octadecenoic ester, formula- C8Hi7(C6H4CH3-)CH=CH C7Hi4COOCHCH2(C2H5) CsHio] was purified by known method by dissolving it in a mixed solvent containing heptane and ethanol. The mixture of oil and solvent was cooled to 12-15°C and the temperature maintained for 5 to 7 h. The upper layer containing oil and solvent was passed through Indian Multani clay column. Solvent was recovered to get purified oil. • EXAMPLE 4 PURIFICATION OF PARTIALLY HYDROGENATED ESTER: Simple ester of ricebran oil partially hydrogenated fatty acid and ethyl hexanol [Having major portion 2Ethyl-1-hexyl-9,octadecenoic ester CeH was purified by known method by dissolving it in a mixed solvent containing heptane and ethanol. The mixture of oil and solvent was cooled to 12-15°C and the temperature maintained for 5 to 7 h. The upper layer containing oil and solvent was passed through clay column. Solvent was recovered to get purified oil. EXAMPLE 5 PREPARATION OF BASE STOCK (A): Purified epoxy ethyl hexyl trans-ester of karanja oil fatty acid 100 % (w/w). The fluid has Kinematic Viscosity at 40°C -54 cst, Viscosity index- 204, Oxidation stability - 0.89 % increase in K.Vis (IP 48/97 ), Flash point-228°C, Pour point - (-)12°C, Acid number- EXAMPLE 6 PREPARATION OF BASE STOCK (B) : 50 % (w/w) of purified alkyl (toluene substituted) ethyl hexyl trans-ester of mahua oil fatty acid and 50 % (w/w) of purified epoxy ethyl hexyl trans-ester of neem oil fatty acid, mixed throughly by stirring at 60°C for 2 hours. The fluid has Kinematic Viscosity at 40°C -52 cst, Viscosity index-250, Oxidation stability - 0.88 % increase in K.Vis (IP 48/97 ), Flash point-208°C, Pour point - (-) 12°C, Acid number- EXAMPLE 7 PREPARATION OF BASE STOCK (C) : 45 % (w/w) of purified alkyl (tolune » substituted) ethyl hexyl trans-ester of mahua oil fatty acid and 55 % (w/w) of purified epoxy ethyl hexyl trans-ester of karanja oil fatty acid, mixed throughly by stirring at 60°C for 2 hours. The fluid has Kinematic Viscosity at 40°C -84.02 cst , Viscosity index- 265, Oxidation stability - 0.9 % increase in K.Vis (IP 48/97 ), Flash point-265°C, Pour point- (-) 12°C, Acid number- EXAMPLE 8 PREPARATION1 OF BASE STOCK (D) : 100 % (w/w) purified ethyl hexyl ester of partially hydrogenated ricebran oil fatty acid. The fluid has Kinematic Viscosity at 40°C -81.4 cst, Viscosity index- 241, Oxidation stability - 0.9 % increase in K.Vis (IP 48/97 ), Flash point-225°C, Pour point - (-) 9°C, Acid number- EXAMPLE 9 PREPARATION OF LUBE OIL FROM BASE STOCK The base stock (A) in 99.797 % (w/w) concentration, was blended with additive octyl 5-amino tetrazole as anti-oxidant in 0.02 % (w/w), dibezyl disulphide in 0.02 % (w/w) & sulfurized nee'm oil in 0.02 % (w/w) as Extreme Pressure additive, Methyl Hydroxy Hydro Cinnamate as lubricity additives in 0.008 % (w/w), pentaethylene hexamine dodecyl succinimide as detergent -dispersant in 0.1 % (w/w), Silicone polymer oil as antifoaming agent- pour point depressant 0.02 % (w/w), and calcium Alkyl Benzene calcium sulfonate as corrosion inhibitors having base number 500 in 0.015 % (w/w) • concentration . The doping was done by known method at 60°C with stirring for 2 hours. The fluid has Kinematic Viscosity at 40°C -55 cst , Viscosity index- 205, Oxidation stability* - 0.88 % increase in K.Vis (IP 48/97 ), Flash point-226°C, Pour point - (-) 15°C, Acid number- nil, Ash sulfated % EXAMPLE 10 PREPARATION OF LUBE OIL FROM BASE STOCK The base stock (B) was blended in 99.865 % (w/w) concentration with additive p-p-dioctyl diphenyl amine as anti-oxidant in 0.01 % (w/w), dibezyl diselenide as Extreme Pressure additive in 0.02 % (w/w), sulfurized ricebran oil as lubricity additives in 0.02 % (w/w), zinc dialkyl dithio phosphate as lubricity additives in 0.005 % (w/w), octyl phosphonate as detergent -dispersant in 0.01 % (w/w), poly vinyl acrylate as antifoaming agent & pour point depressant and 0.02 % (w/w), alkyl benzotriazole as corrosion inhibitors in 0.05 % (w/w) concentration. The doping was done by kown method at 60°C with stirring for 2 hours. The fluid has Kinematic Viscosity at 40°C -53 cst, Viscosity index- 252, Oxidation stability* - 0.75 % increase in K.Vis (IP 48/97 ), Flash point-210°C, Pour point - (-) 12°C, Acid number- nil, Ash sulfated % EXAMPLE 11 PREPARATION OF LUBE OIL FROM BASE STOCK The base stock (C) was blended in 99.86 % (w/w) concentration with additive di-t-butyl 4-methyl phenol as anti-oxidant in 0.01 % (w/w), Molybdenul thiophosphoro pentadecyl phenol in 0.02 % (w/w) & sulfurized hydrogenated karanja oil in 0.02 % (w/w) as Extreme Pressure additives, Methyl Hydroxy Hydro Cinnamate as additives in 0.015 % (w/w), pentaethylene hexamine propylene tetramer succinimide as detergent-dispersant in 0.01 % (w/w), polymethacrylate as antifoaming agent & pour point depressant 0.02 % (w/w), and octyl phosphonate as corrosion inhibitors in 0.045 % (w/w) concentration. The doping was done at 60°C with stirring for 2 hours. The fluid has Kinematic Viscosity at 40°C -85 cst , Viscosity index- 266, Oxidation stability - 0.89 % increase in K.Vis (IP 48/97 ), Flash point-215°C, Pour point - (-) 15°C, Acid number- nil, Ash sulfated % EXAMPLE 12 PREPARATION OF LUBE OIL FROM BASE STOCK The base stock (D) was blended in 99.84 % (w/w) concentration with additive n-naphthyl 2-phenylamine as anti-oxidant in 0.02 % (w/w), molybdenum thiophosphoro luryl oleate in 0.02 % (w/w) & dibenzyl diselenide in 0.02 % (w/w) as Extreme Pressure additive, zinc dialkyl dithiophosphate as lubricity additives in 0.025 % (w/w), pentaettiylene hexamine propylene tetramer succinimide as detergent -dispersant in 0.02 % (w/w), Silicone polymer oil as antifoaming agent & pour point depressant 0.03 % (w/w), and alkyl 1H benzotriazole as corrosion inhibitors in 0.015 % (w/w) concentration and the Octyl phosphate as lubricity enhancer in 0.01 % (w/w). The doping was done by known method at 60°C with stirring for 2 hours. The fluid has Kinematic Viscosity at 40°C -82 cst , Viscosity index- 242, Oxidation stability -0.90 % increase in K.Vis (IP 48/97 ), Flash point-223°C, Pour point - (-) 12°C, Acid number- nil, Ash sulfated % EXAMPLE 13 CHARACTERIZATION AND EVALUATION OF LUBE OIL: The formulations were analyzed and evaluated as per ASTM or BIS methods such as ASTM D445/BIS- 14234, P25/56 -K.Viscosity & Viscosity index, ASTM D 92/BIS-P21/69- Flash point, ASTM D1217/BIS-P16 - Rel.Density, ASTM D130/BIS-P15- Copper corrosion, ASTM D97/BIS-P10- Pour point, ASTM D874/BIS-P4- Ash sulfated, ASTM D 664/BIS-P1- TAN, ASTM D4377/BIS-P40- Water, IP 280, 306, 307-Oxidation Test, ASTM D3711- Cocking test. TYPICAL PERFORMANCE ADVANTAGES OF THE INVENTION The main advantage of the present invention is that the composition of the hydraulic fluid is fairly biodegradable and eco-friendly and provides better or equivalent performance as mineral oil based hydraulic fluids. We Claim: 1. A biodegradable hydraulic fluid composition comprising: i) mono-esters of non-edible vegetable oil fatty acid monoester of fatty acid with C1 to C16 preferably C7 to C12 primary alcohol- in the range of 97.65-99.888 wt%, ii) anti-oxidant selected from the group consisting of hindered phenol, alkyl amine, amino phenol and tetrazole, in the range of 0.006-0.05% by weight, iii) extreme pressure additives selected from the group consisting of sulfurized and selenized organic compounds in the range of 0.006- 0.05% by weight, iv) anti-foaming agent selected from the group consisting of silicone and polymer compound- in the range of 0.01 to 1 .O% by weight, v) pour point depressant selected from the group consisting of adipate and acrylate in the range of 0.01 to 1 .O% by weight, vi) corrosion inhibitor selected from the group consisting of azole, Gallate, polyols, amines, phenols and sulfonates-in the range of 0.03 to 0.1% by weight, vii) detergent -dispersant selected from the group consisting of sulfonate, succinimide and phosphonates in the range of 0.05-0.1 5 % by weight. 2. A composition as claimed in claim 1, wherein the mono-ester of vegetable oil fatty acid used is selected from the group consisting of simple ester, partially hydrogenated ester, epoxy ester, aryl alkyl ester of fatty acids and a mixture thereof. 3. A composition as claimed in claims 1-2, wherein the non-edible vegetable oil triglyceride fatty acid used for making ester is selected from the group consisting of C18:1, C18:2, C18:3 having the mono-unsaturation character in the range of 50 to 70 weight percent. 4. A composition as claimed in claim 1, wherein the non-edible vegetable oil used is selected from the group consisting of karanja (Pongamia glabra) oil, neem (Mellia azadirachta) oil, ricebran (Oryza sativa) oil, mahua (Madhuca indica) oil, castor (Ricinus communis) oil, acetylated castor, linseed (flax-Linium usitatissimum) oil, other vegetable oils and a mixture thereof. 5. A composition as claimed in claim I , wherein the non-edible vegetable oil used is preferably selected from the group consisting of karanja, ricebran, mahua, neem and a mixture thereof. 6. A composition as claimed in claim 1, wherein the mono-esters of fatty acids used as base stock have viscosity (cst) in the range of 50 - 82 at about 40°C and a flash point of 200-240°C (Cleveland Open Cup). 7. A composition as claimed in claims 1, wherein the anti-oxidant used is selected from the group consisting of 2,4,6-tri-tert-butylphenol, 2,6-di-tert-butyl-4-nbutylphenol, 2,6-di-t-butyl-4-methylphenol, bicyclic hindered amines, diphenylamines, dinaphthylamines, 4-methyl-2,6-di-(t-butyl) phenol, methyl hydroxy hydro cinnamide, alkylated 5-amino tetrazole and di-ter butyl p-amino phenol. 8. A composition as claimed in claim 1, wherein the extreme pressure additive used is selected from the group consisting of sulfurized neem oil, sulfurized mahua oil, dibenzyl disulphide, suphurized pentadecyl phenol, thiophosphoro luryl oleate, molybdenum salt of thiophosphoro luryl oleate, zinc dialkyl dithio phosphate, dibenzyl diselenate, selenophosphoro luryl oleate, selenophosphoro pentadecyl phenol and molybdenum thiophosphoro pentadecyl phenol. 9. A composition as claimed in claim 1, wherein the anti-foaming agent used is selected from the group consisting of silicone oil, polyvinyl alcohol and pol yethers. 10. A composition as claimed in claim I , wherein the pour point depressants used is selected from the group consisting of diethylhexyl adipate, polymethacrylate and polyvinylacrylate. 11. A composition as claimed in claim 1, wherein the anti-corrosion additive used is selected from the group consisting of octyl 1 H benzotriazole, ditertiary butylated 1 H-Benzotriazole, propyl gallate, polyoxyalkylene polyols, octadecyl amines, nonyl phenol ethoxylates, calcium phenolates of hydrogenated pentadecyl phenol, and magnesium alkyl benzene sulfonates. 12. A composition as claimed in claim 1, wherein the detergent-dispersant used is selected from the group consisting of amino alkyl benzene sulfonate, calcium alkyl benzene sulfonate, sodium alkyl benzene sulfonate, propylene teramer succinimide of pentaethylene hexamine and octyl phosphonates. 13. A biodegradable hydraulic fluid composition as claimed in claim 1 has the following characteristics: i. kinematic viscosity at about 40°C is in the range of 50-82 cst, ii. viscosity index is ranging between 200-270, iii. oxidation stability is Pass (IP 48197) (1 % increase in viscosity & TAN), iv. rotary bomb oxidation test (ROBOT) at 95OC is between 150-200 min, v. flash point is ranging between 210-240°C, vi. pour point is ranging between (-)9 - (-)25OC, vii. ash sulfated % is ~0.05, viii. copper Strip corrosion test IA, ix. foam test ASTM D 892 Pass, x. emulsion test - 40-39-1 (20), xi. seal test - 312 - 313, xii. lubricity(mm)- Friction coefficient - 0.105 - 0.1 15, xiii. lubricity (mm)- wear scar dia- 0.303 - 0.305, xiv. panel cocking test (20 mg max) Pass, xv. biodegradability is 90-1 00%.

Documents:

785-del-2006-Abstract-(01-02-2013).pdf

785-del-2006-abstract.pdf

785-del-2006-Claims-(01-02-2013).pdf

785-del-2006-claims.pdf

785-del-2006-Correspondence Others-(01-02-2013).pdf

785-del-2006-correspondence-others.pdf

785-del-2006-Description (Complee)-(01-02-2013).pdf

785-del-2006-description(complete).pdf

785-del-2006-form-1.pdf

785-del-2006-form-2.pdf

785-del-2006-Form-3-(01-02-2013).pdf

785-del-2006-form-3.pdf

785-del-2006-form-5.pdf