A biodegradable lubricating grease

Abstract

The present invention provides a biodegradable lubricating grease, belonging to the technical field of lubricating oils. The present invention mixes modified vegetable oil and synthetic oil, adds additives to improve lubricity, extreme pressure resistance, oxidation resistance and other properties, and then adds a small amount of modified mineral oil to mix evenly to obtain biodegradable lubricating grease. The biodegradable lubricating grease prepared by the present invention reduces the usage of modified vegetable oil and synthetic oil, greatly reduces the cost, and the modified mineral oil has excellent degradation performance and does not contain other heavy metals, and will not be toxic to organisms; the obtained lubricating grease has lubrication performance similar to that of mineral oil and can be quickly degraded, and is completely degraded without environmental toxicity, and the 15d biodegradation rate reaches more than 92%.

Description

Technical Field

[0001] The invention belongs to the technical field of lubricating oils, and in particular relates to a biodegradable lubricating grease. Background Art

[0002] Lubricating oil plays an indispensable and key role in equipment operation, such as anti-wear and friction reduction, cooling and improving efficiency, but it usually has poor compatibility with the environment. Traditional mineral lubricating oil has poor biodegradability. If it leaks during production, storage, transportation and use, it will pollute the environment. Due to the poor biodegradability of mineral lubricating oil, coupled with the enhancement of people's environmental awareness and the strictness of national environmental protection regulations, the research and development of biodegradable lubricating oil has received more and more attention.

[0003] At present, biodegradable lubricants have become an important part of green chemistry and green engineering. Biodegradable lubricants refer to lubricants that can meet the use requirements of mechanical equipment and can be decomposed into carbon dioxide and water by active microorganisms in a short time. They are usually included in the list of environmentally friendly lubricants. The performance of environmentally friendly lubricants includes not only biodegradability, but also the ecotoxicity of lubricants. Biodegradability and ecotoxicity are two different aspects. Some toxic substances can also be biodegraded and generate non-toxic substances after degradation; the products of some substances after degradation are more toxic than the original substances. Environmentally friendly lubricants require both good biodegradability and low ecotoxicity and toxic accumulation.

[0004] Bio-lubricants, also known as bio-based environmentally friendly lubricants, refer to lubricants that are partially or completely derived from biological resources or renewable agricultural or forestry resources. In addition to the characteristics of mineral lubricants, bio-lubricants have also attracted much attention due to their renewable raw materials, biodegradability, and low toxicity. Lubricants can be classified into three categories based on different base oils: mineral oil, synthetic oil, and natural vegetable oil. Vegetable oil-based lubricants are environmentally friendly lubricants, such as soybean oil, corn oil, rapeseed oil, cottonseed oil, etc.

[0005] Although natural vegetable oil can be used directly as lubricant, its application is very limited because of its poor oxidation stability. Synthetic lubricants mainly include synthetic hydrocarbons, synthetic esters, polyethers, etc. Among them, synthetic ester oils are the most widely studied. According to surveys, in the global lubricant application market, the proportion of mineral oil is as high as about 85%, vegetable oil accounts for about 2%, and the rest is synthetic oil. Currently, commercially available biodegradable lubricants and greases use a large amount of modified vegetable oil, but the cost of modified vegetable oil is too high, and the lubrication performance and service life are not as good as mineral lubricants; when compounded with synthetic oil and mineral oil, the degradation cycle is long, the degradation is not complete, and it is environmentally toxic. Summary of the invention

[0006] The purpose of the present invention is to provide a biodegradable lubricating grease, which is prepared by mixing modified vegetable oil and synthetic oil with additives to improve lubricity, extreme pressure resistance and oxidation resistance, and then adding a small amount of modified mineral oil, so that the prepared lubricating grease has lubricating properties similar to those of mineral oil and can be quickly degraded, and the degradation is complete while not being environmentally toxic.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention provides a biodegradable lubricating grease, which is composed of the following raw materials in parts by weight:

[0009] 40-60 parts of boron-nitrogen modified rapeseed oil, 1-10 parts of neopentyl glycol diester, 1-10 parts of diisooctyl sebacate, 10-20 parts of mineral oil, 1-5 parts of lauroyl glutamic acid, 5-10 parts of antioxidant, 1-3 parts of thickener, 1-5 parts of viscosity modifier, 1-5 parts of defoaming agent, 1-5 parts of phosphate ester, 1-3 parts of molybdenum powder microspheres, 5-10 parts of sodium petroleum sulfonate, 5-10 parts of polyol, and 5-10 parts of oleic acid.

[0010] Preferably, the antioxidant is a phenolic antioxidant or an amine antioxidant.

[0011] Preferably, the thickener is graphite, carbon black or higher fatty acid soap.

[0012] Preferably, the defoaming agent is polyacrylate.

[0013] Preferably, the particle size of the molybdenum powder microspheres is 20-60 nm.

[0014] The present invention also provides a method for preparing a biodegradable lubricating grease, comprising the following steps:

[0015] 1) weighing the raw materials according to the mass parts;

[0016] 2) placing boron-nitrogen modified rapeseed oil, neopentyl glycol diester, diisooctyl sebacate, molybdenum powder microspheres, sodium petroleum sulfonate and antioxidant in a reaction kettle in sequence, stirring and heating until uniform to obtain mixed oil A;

[0017] 3) mixing mineral oil, lauroyl glutamic acid, polyol and oleic acid to obtain mixed oil B;

[0018] 4) Mixed oil A and mixed oil B are placed in a reaction kettle, heated and stirred, and thickener, viscosity modifier, defoamer and phosphate ester are added in sequence and stirred at constant temperature for 50 minutes to obtain a biodegradable lubricating grease.

[0019] Preferably, in step 2), the heating temperature is 30-60° C. and the heating time is 30-60 min.

[0020] Preferably, the heating temperature in step 4) is 90-120°C.

[0021] Preferably, in step 4), the constant temperature is 90-120° C. and the stirring time is 40-60 min.

[0022] Beneficial technical effects of the present invention:

[0023] The present invention provides a biodegradable lubricating grease, wherein modified vegetable oil and synthetic oil are mixed with additives to improve lubricity, extreme pressure resistance, oxidation resistance and other properties, and then a small amount of modified mineral oil is added to obtain the biodegradable lubricating grease. The biodegradable lubricating grease prepared by the present invention reduces the usage of modified vegetable oil and synthetic oil, greatly reduces the cost, and the modified mineral oil has excellent degradation performance and does not contain other heavy metals, and will not be toxic to organisms; the obtained lubricating grease has lubrication performance similar to that of mineral oil and can be quickly degraded, and is completely degraded without environmental toxicity, and the 15-day biodegradation rate reaches more than 92%. DETAILED DESCRIPTION

[0024] The present invention provides a biodegradable lubricating grease, which is composed of the following raw materials in parts by weight:

[0025] 40-60 parts of boron-nitrogen modified rapeseed oil, 1-10 parts of neopentyl glycol diester, 1-10 parts of diisooctyl sebacate, 10-20 parts of mineral oil, 1-5 parts of lauroyl glutamic acid, 5-10 parts of antioxidant, 1-3 parts of thickener, 1-5 parts of viscosity modifier, 1-5 parts of defoaming agent, 1-5 parts of phosphate ester, 1-3 parts of molybdenum powder microspheres, 5-10 parts of sodium petroleum sulfonate, 5-10 parts of polyol, and 5-10 parts of oleic acid.

[0026] In the present invention, the boron-nitrogen modified rapeseed oil improves lubricity and extreme pressure resistance by introducing boron and nitrogen elements into the rapeseed oil.

[0027] In the present invention, the weight parts of the biodegradable lubricating grease raw materials are preferably: 45-55 parts of boron-nitrogen modified rapeseed oil, 3-7 parts of neopentyl glycol diester, 3-7 parts of diisooctyl sebacate, 13-17 parts of mineral oil, 2-4 parts of lauroyl glutamic acid, 7-9 parts of antioxidant, 2-3 parts of thickener, 3-4 parts of viscosity modifier, 3-4 parts of defoamer, 3-4 parts of phosphate ester, 1-3 parts of molybdenum powder microspheres, 6-9 parts of sodium petroleum sulfonate, 6-9 parts of polyols, and 6-9 parts of oleic acid; more preferably, 50 parts of boron-nitrogen modified rapeseed oil, 6 parts of neopentyl glycol diester, 6 parts of diisooctyl sebacate, 15 parts of mineral oil, 3 parts of lauroyl glutamic acid, 8 parts of antioxidant, 3 parts of thickener, 4 parts of viscosity modifier, 4 parts of defoamer, 4 parts of phosphate ester, 3 parts of molybdenum powder microspheres, 7 parts of sodium petroleum sulfonate, 7 parts of polyols, and 7 parts of oleic acid.

[0028] In the present invention, the antioxidant is preferably a phenolic antioxidant or an amine antioxidant; more preferably a phenolic antioxidant.

[0029] In the present invention, the thickener is preferably graphite, carbon black or higher fatty acid soap; more preferably graphite.

[0030] In the present invention, the defoamer is preferably polyacrylate. The defoamer is added to reduce bubbles during mixing and prevent the lubricating grease from generating foam during long-term use, thereby increasing its service life.

[0031] In the present invention, the particle size of the molybdenum powder microspheres is 20-60nm. The present invention improves the lubricating effect and extreme pressure resistance of lubricating grease by adding nano molybdenum powder microspheres, and does not affect the environment.

[0032] The present invention also provides a method for preparing a biodegradable lubricating grease, comprising the following steps:

[0033] 1) weighing the raw materials according to the mass parts;

[0034] 2) placing boron-nitrogen modified rapeseed oil, neopentyl glycol diester, diisooctyl sebacate, molybdenum powder microspheres, sodium petroleum sulfonate and antioxidant in a reaction kettle in sequence, stirring and heating until uniform to obtain mixed oil A;

[0035] 3) mixing mineral oil, lauroyl glutamic acid, polyol and oleic acid to obtain mixed oil B;

[0036] 4) Mixed oil A and mixed oil B are placed in a reaction kettle, heated and stirred, and thickener, viscosity modifier, defoamer and phosphate ester are added in sequence and stirred at constant temperature for 50 minutes to obtain a biodegradable lubricating grease.

[0037] In the present invention, the heating temperature in step 2) is preferably 30-60°C, more preferably 40-50°C; the heating time is preferably 30-60min, more preferably 40-50min.

[0038] In the present invention, the heating temperature in step 4) is preferably 90-120°C, more preferably 100-110°C; the constant temperature is preferably 90-120°C, more preferably 100-110°C; the stirring time is preferably 40-60min, more preferably 50min.

[0039] The invention improves the lubrication performance of the modified rapeseed oil by uniformly mixing the modified rapeseed oil and the synthetic diester after adding an additive, and simultaneously improves the biodegradability without generating biotoxins.

[0040] The invention not only improves the biodegradability of the mineral oil but also makes it more evenly mixed with the mixed oil A by mixing the mineral oil with lauroyl glutamic acid, polyol and oleic acid, so that the dispersion of various modifiers is higher, and the lubricating performance and service life of the lubricating grease are improved.

[0041] The present invention finds that increasing the temperature when mixed oil A and mixed oil B are mixed can increase the biodegradation speed and efficiency. Since mixed oil A is a modified vegetable oil, the activity of microorganisms is increased under the action of a biodegradation accelerator, and at the same time, the degradation degree of mineral oil that is difficult to decompose itself is further increased.

[0042] Example 1

[0043] 1) 50 parts of boron-nitrogen modified rapeseed oil, 6 parts of neopentyl glycol diester, 6 parts of diisooctyl sebacate, 3 parts of molybdenum powder microspheres, 7 parts of sodium petroleum sulfonate and 8 parts of phenolic antioxidant were placed in a reaction kettle in sequence and stirred and heated at 45° C. for 45 min to obtain mixed oil A.

[0044] 2) 15 parts of mineral oil, 3 parts of lauroyl glutamic acid, 7 parts of polyol and 7 parts of oleic acid were uniformly mixed to obtain mixed oil B;

[0045] 3) Mixed oil A and mixed oil B are placed in a reaction kettle, heated and stirred at 105° C., and 3 parts of graphite, 4 parts of viscosity modifier, 4 parts of polyacrylate and 4 parts of phosphate are added in sequence, and stirred at a constant temperature of 105° C. for 50 minutes to obtain a biodegradable lubricating grease.

[0046] Example 2

[0047] 1) 40 parts of boron-nitrogen modified rapeseed oil, 1 part of neopentyl glycol diester, 1 part of diisooctyl sebacate, 1 part of molybdenum powder microspheres, 5 parts of sodium petroleum sulfonate and 5 parts of phenolic antioxidant were placed in a reaction kettle in sequence and stirred and heated at 30° C. for 30 min to obtain mixed oil A.

[0048] 2) 10 parts of mineral oil, 1 part of lauroyl glutamic acid, 5 parts of polyol and 5 parts of oleic acid were uniformly mixed to obtain mixed oil B;

[0049] 3) Mixed oil A and mixed oil B are placed in a reaction kettle, heated and stirred at 105° C., and 1 part of carbon black, 1 part of viscosity modifier, 1 part of polyacrylate and 1 part of phosphate ester are added in sequence, and stirred at a constant temperature of 90° C. for 40 minutes to obtain a biodegradable lubricating grease.

[0050] Example 3

[0051] 1) 60 parts of boron-nitrogen modified rapeseed oil, 10 parts of neopentyl glycol diester, 10 parts of diisooctyl sebacate, 3 parts of molybdenum powder microspheres, 10 parts of sodium petroleum sulfonate and 10 parts of phenolic antioxidant were placed in a reaction kettle in sequence and stirred and heated at 60° C. for 60 min to obtain mixed oil A.

[0052] 2) 20 parts of mineral oil, 5 parts of lauroyl glutamic acid, 10 parts of polyol and 10 parts of oleic acid were uniformly mixed to obtain mixed oil B;

[0053] 3) Mixed oil A and mixed oil B are placed in a reactor, heated and stirred at 105°C, and 3 parts of higher fatty acid soap, 5 parts of viscosity modifier, 5 parts of polyacrylate and 5 parts of phosphate are added in sequence, stirred at a constant temperature of 110°C for 60 minutes to obtain a biodegradable lubricating grease. Performance analysis table is shown in Table 1:

[0054] Table 1 Performance test table

[0055] Test items Friction factor <![CDATA[Viscosity mm 2 / s]]> Extreme pressure and anti-wear PB / N Biodegradation rate 15d Example 1 0.8 283.5 3986 95.3％ Example 2 0.9 294.3 3814 93.1％ Example 3 0.8 276.6 3906 93.7％

Claims

1. A biodegradable lubricating grease, characterized in that: Prepared by the following steps: 1) 50 parts of boron-nitrogen modified rapeseed oil, 6 parts of neopentyl glycol diester, 6 parts of diisooctyl sebacate, 3 parts of molybdenum powder microspheres, 7 parts of sodium petroleum sulfonate and 8 parts of phenolic antioxidant were placed in a reaction kettle in sequence and stirred and heated at 45° C. for 45 minutes to obtain mixed oil A; 2) 15 parts of mineral oil, 3 parts of lauroyl glutamic acid, 7 parts of polyol and 7 parts of oleic acid were uniformly mixed to obtain mixed oil B; 3) Mixed oil A and mixed oil B are placed in a reaction kettle, heated and stirred at 105° C., and 3 parts of graphite, 4 parts of viscosity modifier, 4 parts of polyacrylate and 4 parts of phosphate are added in sequence, and stirred at a constant temperature of 105° C. for 50 minutes to obtain a biodegradable lubricating grease.