A plant based industrial lubricant formulation

Abstract

The present invention discloses a plant based industrial lubricant formulation that includes three major components. The first component includes at least one constituent such as ester of soyabean oil, ester of sesame oil, ester of corn oil, ester of caster oil, ester of canola, ester of safflower oil and the like. The second component includes at least one of the constituents including Sapindus mucorossi, neem oil and calendula oil. Further, the third component is a nanoparticle component which includes Zinc Sulfide nanoparticles, hexagonal boron nitrate nanoparticles and molebdenum disulfide nanoparticles. Also disclosed is a process for preparation of a plant based industrial lubricant of the present invention. This lubricant formulation has varied applications in various industries due to adjustable viscosities and flashpoints.

Description

[0001] “A PLANT BASED INDUSTRIAL LUBRICANT FORMULATION”

[0002] FIELD OF THE INVENTION:

[0003] The present invention relates to a plant based lubricant formulation and particularly to a plant based lubricant formulation for lubrication of industrial machinery.

[0004] BACKGROUND OF THE INVENTION:

[0005] A lubricant is a substance used to coat surfaces that move relative to each other. The main purpose of lubricants is to decrease friction and minimize wear and tear of these surfaces. Lubricants also act as a barrier against moisture and corrosive substances, protecting metal parts from rust and corrosion. Further, lubricants help dissipate heat generated by friction, preventing overheating of machinery. Other applications of lubricants include sealing gaps between parts, to prevent contamination and maintaining pressure; transmission of power, as observed in hydraulic systems and the like.

[0006] Various types of lubricants cater to different requirements and applications. Liquid lubricants are the most common and include various oils such as mineral oils, synthetic oils, emulsions, etc. Solid lubricants are commonly used in high temperature or high-vacuum environments where liquid lubricants are not suitable. Examples of solid lubricants include graphite, molybdenum disulfide and the like. Semi-solid lubricants are also used in certain conditions and commonly include oils that have been thickened with soap. Further, gases such as air are also known to be utilized as lubricants in certain cases. Lubricants are generally used in the automotive industry, industrial purposes, food processing equipment, medical equipment and the like.

[0007] Primarily, industrial lubricants are derived from synthetic and petroleumbased lubricants. Such synthetic lubricants are not readily biodegradable and are toxic. Further, disposal of such conventional lubricants becomes an issue. The breakdown of synthetic lubricants into simpler substances indeed lead to higher operational costs for industrial processes. This breakdown often requires additional processing steps, energy, and resources, increasing overall expenses. Companies may also need to invest in specialized technologies or equipment to facilitate the breakdown process.

[0008] Plant based lubricants or bio-lubricants are being looked at as an alternative to conventional petroleum based lubricants. Plant based lubricants are typically made from oils such as soyabean oil, canola oil, etc. However, oxidation of the plant based lubricants, compatibility with existing equipment, high cost and effect on efficiency are some challenges that are posed before the use of plant based lubricants in any industry. Plant based lubricants are known to reduce environmental impact due to their biodegradability and derivation from renewable sources. Further, they also provide technical benefits such as superior lubricity and a high viscosity index. Also, plant based lubricants are low in toxicity, serving as environmentally friendly alternatives to conventional petroleum-based lubricants.

[0009] Biodegradable oils and lubricants that include animal fats and vegetable oils are available in the market. However, these lubricants have high costs and very high viscosity index such as 223 that leads to excessive heat generation. This leads to high mechanical shear causing damage to the industrial machinery. Further, these lubricants do not have any biocidal properties to protect the machinery from any type of microbial contamination.

[0010] The Patent Application WO2023203542A1 to Priya Satish Singh, et al; discloses a lubricant formulation and method of lubricating a dry surface. The lubricant includes vegetable oil, surfactant and water. However, this formulation employs chemicals like surfactants and is a dry lubricant. Further, this formulation is a dry lubricant that needs addition of a solvent to liquify the composition.

[0011] The Chinese Patent Application CN104711100A to Shi Yong, discloses a fluid formulation for machining and a machining method. The fluid formulation includes soluble oil and semisynthetic water-based fluid that forms an emulsion. However, this formulation employs chemicals like surfactants and includes a majority component of which may make the formulation non compatible with certain requirements or applications such as industrial machining, and the like.

[0012] Therefore, there is a need for a plant based lubricant for industrial machinery that is biosynthetic and economical as well. There is also a need for a plant based lubricant that is operational in varied industries and adjustable as per to the need of the user.

[0013] SUMMARY OF THE INVENTION:

[0014] The present invention discloses a plant based industrial lubricant formulation that is water free including three components. The component 1 is a base oil blend such that it includes 60-99.7 wt% of one or more bio-esters selected from soybean oil esters, castor oil esters, canola oil esters, safflower oil esters, sesame oil esters, corn oil esters, rice-bran oil esters, and soy oil methyl ester. Component 2 of the present invention is a functional natural additives that is 0.1- 3.0 wt% of one or more of Sapindus mucorossi extract, neem oil, and calendula oil. Further, Component 3 include solid-lubricant nanoparticles such that a total of 0.2-

[0015] 1.0 wt% include hexagonal boron nitride(h-BN), molybdenum disulfide (M0S2) and zinc sulfide (ZnS), each present at 0.05-0.6 wt% wherein water is <0.5 wt% of the formulation.

[0016] Further, the kinematic viscosity of the present invention is < 15 cSt at 40 ° C (ASTM D445) that is suitable for aerosol delivery. The kinematic viscosity >20 cSt at 40 °C (ASTM D445) of the present invention allows it to be suitable for liquid-phase industrial lubrication. The flash point (ASTM D92) of the formulation of the present invention is tunable between 220-300 °C by adjusting the castor-to- soybean ester ratio. The formulation of the present invention exhibits antimicrobial activity attributable to 0.1-3.0 wt% neem oil in Component 2, as demonstrated by a reduction in viable microbial load in a standardized microbiological assay. The formulation of the present invention exhibits a coefficient of friction <0.08 and a wear-scar diameter <0.40 mm in ASTM D4172 (40 kg, 75 ° C, 60 min) and passes

[0017] ASTM D665 (A and / or B) corrosion tests. The present invention achieves >60% biodegradation within 28 days in a ready-biodegradability test (e.g., OECD 301 or ASTM D5864) and meets ASTM D892 foaming limits (Sequences I— III). Further, the formulation of the present invention has a viscosity index >160 (ASTM D2270).

[0018] The present invention is a formulation made by a process including several steps. First, oils of Component 1 are blended at 45-55 °C for 6-10 h. Next, the Component 3 are dispersed at 0.2-1.0 wt% by ultrasonic sonication at ~20 kHz, 50-70% amplitude for 10-30 min, while maintaining the bulk temperature <60 °C, to obtain a nanoparticle dispersion with D90 <500 nm. In the next step, Component 2 is incorporated at 30-50 °C under slow agitation. Further, in the next step, transesterification / chain-extension is performed with 0.05-0.2 wt% catalyst at 60- 90 °C for 30-120 min, followed by neutralization. Finally, the formulation is settled and filtered through a 5-20 pm filter to obtain the finished formulation.

[0019] The formulation of the present invention is adjusted to <15 cSt at 40 ° C (ASTM D445) for aerosol-grade applications and is also adjusted to >20 cSt at 40 °C (ASTM D445) for liquid-grade industrial applications. The formulation of the castor-to-soybean ester weight ratio is from 1:9 to 9: 1 and water content is <0.2 wt%. DESCRIPTION OF THE INVENTION:

[0020] References in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.

[0021] References in the specification to “preferred embodiment” means that a particular feature, structure, characteristic, or function described in detail thereby omitting known constructions and functions for clear description of the present invention.

[0022] The foregoing description of specific embodiments of the present invention has been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed and obviously many modifications and variations are possible in light of the above teaching.

[0023] In a general aspect, the present invention discloses a plant based industrial lubricant formulation. The present invention is an alternative to traditional lubricants such as those used in industrial machinery, vehicles, and the like. The present invention further includes the use of cheaper components that decrease the overall manufacturing cost of the product. Also, lesser components in the formulation of the present invention leads to a less complex process.

[0024] In one aspect, the present invention discloses a plant based industrial lubricant formulation. In another aspect, the present invention describes a process of preparation of the plant based industrial lubricant formulation.

[0025] In accordance with a preferred embodiment, the present invention is a plant based industrial lubricant formulation that includes:

[0026] A) Component 1 including at least one of the following: i) Ester of Soyabean oil- 40-70 % w / w ii) Ester of Caster oil - 40-70% w / w iii) Soy oil methyl ester-20-40 % w / w iv) Sesame oil- 40-70% w / w v) Com oil- 40-70% w / w vi) Rice bran oil- 40-70% w / w vii) Ester of Canola-40-70% w / w viii) Safflower oil- 40-70% w / w

[0027] In accordance with the present inventio, Component 1 is a primary diluent and provides inherent antioxidant properties due to naturally occurring tocopherols and other stabilizers, contributing to oxidative stability of the formulation.

[0028] B) Component 2 including at least one of the following: i) Sapindus mucorossi- 0.1-3% w / w ii) Neem oil- 0.1-3% w / w iii) Calendula oil-0.1-2% w / w

[0029] It is noted that the inclusion of Component 2 delivers self-cleaning, anti-microbial, and sensory benefits beyond conventional lubricants.

[0030] Component 3 includes: i) Zinc Sulfide (ZnS) Nanoparticles ii) Hexagonal Boron Nitrate (h-BN) Nanoparticles iii) Molybdenum disulfide (MoS2) Nanoparticles

[0031] In accordance with the present invention, the component 3 acts as a nanoparticulate lubricant, improving wear resistance and reducing friction. In one embodiment, each nanoparticle species is present at <0.033 wt%, with a combined loading of about 0.1 wt%. The ratio of base oil blend (Component 1) to additives (Components 2 and 3) is maintained at approximately 3: 1.

[0032] In accordance with a preferred embodiment, the present invention includes a plant-based industrial lubricant formulation comprising three principal components. Component 1 functions as the base oil of the formulation. It provides the bulk of the composition and serves as the carrier or diluent for the other components. In addition, these bio-esters inherently contain naturally occurring antioxidants, which impart oxidative stability to the formulation. At least one of the specified esters such as soybean, castor, canola, safflower, sesame, corn, or ricebran oil esters, or soy oil methyl ester is incorporated depending on user requirements and desired performance characteristics.

[0033] Component 2 has functional natural additives, which are incorporated as required to impart specialized properties. For example, Sapindus mucorossi extract acts as a natural surfactant, lowering surface tension and improving spreading and wetting of the lubricant film. Neem oil contributes biocidal and antimicrobial activity, protecting machinery from microbial contamination. Calendula oil reduces or eliminates undesirable odors in the formulation, thereby improving handling and user acceptability.

[0034] Component 3 is a nanoparticle additive package, that enhances lubricity and wear resistance. In one embodiment, this component comprises zinc sulfide (ZnS), hexagonal boron nitride (h-BN), and molybdenum disulfide (M0S2) nanoparticles, each present in an amount of <0.033 wt%, with a total nanoparticle loading of about 0.1 wt%. The ratio of base oils (Component 1) to the combined additives (Components 2 and 3) is approximately 3: 1. These nanoparticles are used at concentrations well below established safety thresholds, require no special handling expertise, and can be incorporated without significant additional safety measures or cost.

[0035] This combination of components forms a balanced, cost-effective, and environmentally safe lubricant that delivers enhanced oxidative stability, antimicrobial protection, and reduced friction while remaining free from toxic or hazardous materials.

[0036] Now referring to FIG. 1, a preferred process for the preparation of the formulation of a plant based industrial lubricant in accordance with the present invention is disclosed. The process for preparing the formulation of the plant based industrial lubricant of the present invention includes a plurality of cycles as described below.

[0037] In a first selection cycle (104), at least one of constituents of the Component 1 i.e. ester of an oil having monosaturated and / or polysaturated fats or the like is selected as a base oil. In a second mixing cycle (108), any other ester oil of component 1 is added to the selected base oil as per the user’ s requirement and the mixture is blended for a predefined temperature and time. In a third sonication cycle (112), the mixture of oils with the nanoparticles undergoes sonication at predefined parameters. The cavitation bubbles collapse and release energy. Sonication includes high frequency waves that form cavitation bubbles in the liquid mixture of the previous cycle. Further, Sonication allows for mixing and homogenizing the liquid mixture. In a fourth combination cycle (116), the combination of nanoparticles of Component 3 is added to the blend of oils while blending.

[0038] In a fifth additive cycle (120), the group of additives from Component 2 are added to the mixture of previous step. In a sixth esterification and polymerization cycle (124), smaller oil molecules of the mixture are linked together into larger oil molecules that improve the oxidative stability and viscosity of the formulation. In a seventh blending cycle (128), the entire mixture of all the constituents is blended further for 30 mins. Further, in an eighth cooling cycle (132), a cooling cycle is conducted so that the temperature of the total formulation reaches room temperature. In a ninth settling cycle (136), the lubricant formulation is allowed to settle for a predefined time so that any particulate matter settles. In a final filtration cycle (140), the lubricant formulation of the present invention is further filtered through coarse filters to result in the lubricant formulation of the present invention.

[0039] In accordance with the present invention, in the second mixing cycle (108), the mixture is blended for 8 hours at 47 °C (±2 °C), with the target temperature being reached within the first 4 hours of operation. In the third combination cycle (112), the mixture undergoes ultrasonic dispersion at 20 kHz frequency, 60% amplitude, for 20-30 minutes at a controlled temperature below 60 °C, ensuring uniform distribution of the nanoparticles and preventing agglomeration. In the ninth settling cycle (136), the lubricant formulation is allowed to stand undisturbed for 12 hours at ambient temperature (25 ± 2 °C) to allow any residual particulate matter to settle.

[0040] It was observed that the lubricant formulation of the present invention demonstrated approximately three times higher efficiency compared to conventional water-based lubricants and about twice the efficiency of traditional synthetic oil-based lubricants, as determined in controlled machining trials that measured spindle load reduction, axis load reduction, and temperature rise during operation.

[0041] The flash point of an oil is defined as the lowest temperature at which its vapours ignite momentarily when exposed to a small flame, typically measured according to ASTM D92 (Cleveland Open Cup method). The flash point is a critical indicator of the oil’s fire and explosion hazard, suitability under various operating conditions, and potential contamination. Conventional mineral-based industrial lubricants generally exhibit flash points in the range of 165-270 °C (ASTM D92).

[0042] In accordance with the present invention, the flash point of the lubricant formulation is tuned by adjusting the ratio of its bio-ester constituents. For example, soybean oil ester has a flash point of approximately 282 °C, while castor oil ester exhibits a flash point of about 229-230 °C. Thus, if a lower flash point formulation is desired, the relative proportion of castor oil ester is increased, whereas for a higher flash point, the proportion of soybean oil ester is increased. This tunability allows the lubricant formulation of the present invention to be applied across a wide range of industries, including the automotive sector, tools and machinery industry, and general industrial lubrication.

[0043] Further, it is well known that the kinematic viscosity of conventional liquid industrial lubricants typically ranges from 20 to 75 centistokes (cSt) at 40 °C, as determined by ASTM D445. In contrast, lubricants intended for use in an aerosol format require a viscosity of less than 20 cSt at 40 °C (ASTM D445) to achieve proper atomization and spray performance. Consequently, conventional liquid industrial lubricants cannot generally be converted into aerosol products and therefore are unsuitable for use in industries such as metal cutting, where aerosolbased lubricants are often preferred.

[0044] In accordance with the present invention, the viscosity of the plant-based lubricant formulation is advantageously tunable, such that it can be adjusted below 15 cSt at 40 °C for aerosol-grade applications or maintained above 20 cSt at 40 °C for liquid-grade applications, depending on the user’s requirement and end-use industry.

[0045] The kinematic viscosity of the lubricant formulation is primarily determined during the sixth cycle of the process, which involves esterification and polymerization. In this stage, the extent of molecular bonding is controlled to increase or decrease the average chain length of the oil molecules, thereby adjusting the viscosity of the final product. When the kinematic viscosity of the formulation is tuned to below 15 centistokes (cSt) at 40 °C, as measured according to ASTM D445, the product is suitable for use in aerosol form, ensuring effective atomization and spray delivery. Such aerosol-grade lubricant formulations are particularly useful in industries such as the automotive sector, and also serve as anti-corrosive protective coatings.

[0046] Conversely, when the kinematic viscosity is maintained above 15 cSt at 40 °C (ASTM D445), the formulation remains in liquid form, making it suitable for industrial machining tools, automotive systems, and general machinery lubrication, where higher viscosity is required for load-bearing and wear protection.

[0047] EXAMPLES:

[0048] Only a few examples and implementations are disclosed. Variations, modifications, and enhancements to the described examples and implementations and other implementations can be made based on what is disclosed.

[0049] Examples are set forth herein below and are illustrative of different amounts and types of reactants and reaction conditions that can be utilized in practicing the disclosure. It will be apparent, however, that the disclosure can be practiced with other amounts and types of reactants and reaction conditions than those used in the examples, and the resulting devices various different properties and uses in accordance with the disclosure above and as pointed out hereinafter.

[0050] Example 1: Combination 1:

[0051] The plant based industrial lubricant formulation is as provided below:

[0052] Table No. 1

[0053] It was observed that the formulation of the present invention reduced spindle load by approximately 53%, axis load by approximately 35%, and resulted in a measurable reduction in operating temperature compared to conventional lubricants. These improvements showed lower energy consumption, reduced wear of machine components, and extended tool life.

[0054] Table No. 2

[0055] The components listed in Table 1 were combined according to the process of the present invention to obtain the lubricant formulation. As shown in Table 2, the use of this formulation in machining trials resulted in a 53 % reduction in spindle load compared to conventional lubricants. Additionally, the axis load of the CNC machine tool decreased by approximately 35%, and the delta temperature between pre- and post-machining cycles was reduced by 5 °C when the lubricant formulation of the present invention was employed. In accordance with the present invention, the reduction in spindle and axis loads translates into lower electrical power consumption, extended machine life, and reduced maintenance requirements. Furthermore, the decrease in mechanical stresses and thermal rise allows the machining cycle time to be shortened, thereby improving productivity. It was further observed that the use of the lubricant formulation extended the service life of cutting tools by up to two times compared to conventional lubricants.

[0056] Example 2: Combination 2:

[0057] The plant based industrial lubricant formulation is as provided below:

[0058] Table No. 3

[0059] The combination described in Table 3 produces a high-viscosity lubricant formulation, exhibiting a kinematic viscosity greater than 20 centistokes (cSt) at 40 °C, as determined by ASTM D445. Such higher-viscosity formulations are particularly suited for use in industrial machining tools, automotive engines, heavy- duty gear systems, and similar applications where strong lubricating films and enhanced load-bearing capacity are required.

[0060] Example 3: Combination 3:

[0061] A third representative formulation of the plant-based industrial lubricant was prepared as follows:

[0062] Table No. 4

[0063] The combination described in Table 4 results in the formation of a reduced- viscosity lubricant formulation, exhibiting a kinematic viscosity of less than 15 centistokes (cSt) at 40 °C, as measured according to ASTM D445. Such lower- viscosity formulations are advantageous for applications requiring rapid flow and friction reduction, including use in household appliances, light-duty automotive components, precision instruments, and similar systems where reduced-viscosity lubricants are preferred.

[0064] Advantageously, the plant-based industrial lubricant formulation of the present invention requires significantly smaller quantities for effective operation compared to conventional industrial machine lubricants, many of which rely on large volumes of water as the primary component. The formulation is further tunable across a wide viscosity range (below 15 cSt to above 20 cSt at 40 °C, ASTM D445), thereby enabling its use in a broad spectrum of industries and applications, from household and automotive systems to heavy-duty industrial machinery. In addition, the formulation inherently provides anti-microbial activity due to the inclusion of natural biocidal components (e.g., neem oil), which form a protective coating on machine surfaces, thereby acting as a biocide against microbial contamination. The lubricant is non-hazardous, toxin-free, and readily biodegradable, offering a safer alternative to conventional mineral or synthetic oils. Importantly, the formulation is completely water-free, which not only reduces the overall volume of lubricant required but also minimizes issues related to microbial growth, corrosion, and coolant disposal that are typically associated with waterbased lubricants.

[0065] The plant-based industrial lubricant formulation disclosed herein is manufactured using commercially available raw materials and established blending, sonication, and filtration techniques. The formulation is applicable to a wide range of industries including automotive, heavy machinery, aerospace, metal cutting, general engineering, and household applications.

[0066] The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others, skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated.

[0067] It is understood that various omission and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such are intended to cover the application or implementation without departing from the scope of the present invention.

Claims

CLAIMS:

1. A plant based industrial lubricant formulation that is water free comprising: component 1 (base oil blend): 60-99.7 wt% of one or more bio-esters selected from soybean oil esters, castor oil esters, canola oil esters, safflower oil esters, sesame oil esters, com oil esters, rice-bran oil esters, and soy oil methyl ester; component 2 (functional natural additives): 0.1-3.0 wt% of one or more of Sapindus mucorossi extract, neem oil, and calendula oil; and component 3 (solid-lubricant nanoparticles): a total of 0.2-1.0 wt%, including hexagonal boron nitride(h-BN), molybdenum disulfide (M0S2) and zinc sulfide (ZnS), each present at 0.05-0.6 wt%; wherein water is <0.5 wt% of the formulation.

2. The plant based industrial lubricant formulation as claimed in claim 1, having a kinematic viscosity <15 cSt at 40 ° C (ASTM D445) suitable for aerosol delivery.

3. The plant based industrial lubricant formulation as claimed in claim 1, having a kinematic viscosity >20 cSt at 40 °C (ASTM D445) suitable for liquid-phase industrial lubrication.

4. The plant based industrial lubricant formulation as claimed in claim 1; wherein the flash point (ASTM D92) being tunable between 220-300 °C by adjusting the castor-to- soybean ester ratio.

5. The plant based industrial lubricant formulation as claimed in claim 1, exhibiting antimicrobial activity attributable to 0.1-3.0 wt% neem oil in Component 2, as demonstrated by a reduction in viable microbial load in a standardized microbiological assay.

6. The plant based industrial lubricant formulation as claimed in claim 1, exhibiting a coefficient of friction <0.08 and a wear-scar diameter <0.40 mm in ASTM D4172 (40 kg, 75 ° C, 60 min).

7. The plant based industrial lubricant formulation as claimed in claim 1, passing ASTM D665 (A and / or B) corrosion tests.

8. The plant based industrial lubricant formulation as claimed in claim 1 achieving >60% biodegradation within 28 days in a ready-biodegradability test (e.g., OECD 301 or ASTM D5864).

9. The plant based industrial lubricant formulation as claimed in claim 1 meeting ASTM D892 foaming limits (Sequences I— III).

10. The plant based industrial lubricant formulation as claimed in claim 1 having a viscosity index >160 (ASTM D2270).

11. A process for producing the formulation of claim 1, comprising:(i) blending Component 1 oils at 45-55 °C for 6-10 h;(ii) dispersing Component 3 at 0.2-1.0 wt% by ultrasonic sonication at ~20 kHz, 50-70% amplitude for 10-30 min, while maintaining the bulk temperature <60 °C, to obtain a nanoparticle dispersion with D90 <500 nm;(iii) incorporating Component 2 at 30-50 °C under slow agitation;(iv) optionally performing transesterification / chain-extension with 0.05-0.2 wt% catalyst at 60-90 °C for 30-120 min, followed by neutralization; and(v) settling and filtering through a 5-20 pm filter to obtain the finished formulation.

12. The process for producing the formulation as claimed in claim 11; wherein the formulation is adjusted to < 15 cSt at 400C (ASTM D445) for aerosolgrade applications.

13. The process for producing the formulation as claimed in claim 11; wherein the formulation is adjusted to >20 cSt at 40 °C (ASTM D445) for liquidgrade industrial applications.

14. The process for producing the formulation as claimed in claim 1; wherein the castor-to- soybean ester weight ratio is from 1:9 to 9: 1.

15. The plant based industrial lubricant formulation as claimed in claim 1; wherein water is <0.2 wt%.

Images