CN103589478B - A kind of lubricating oil containing Il/Mongolian clay nano-powder and its preparation method - Google Patents

Abstract

The invention discloses a lubricating oil containing illite/montmorillonite clay nano powder and a preparation method thereof, belonging to the field of new application of phyllosilicate clay minerals. The lubricating oil is composed of oleic acid modified illite/montmorillonite clay nano powder and III type base oil, wherein the oleic acid modified illite/montmorillonite clay nano powder accounts for 0.5-2.5 wt% of the lubricating oil. The preparation method comprises the following steps: (1) crushing natural illite/montmorillonite clay minerals, and adding water to obtain a slurry; (2) regulating the pH value of the slurry, and dispersing; (3) screening the slurry through a sieve; (4) grinding the undersieve slurry to obtain a nano slurry; (5) adding oleic acid for modification; (6) drying the modified nano slurry to obtain nano dry powder; and (7) mixing the nano dry powder with III type base oil to obtain the lubricating oil containing illite/montmorillonite clay nano powder. By using the illite/montmorillonite clay nano powder as the additive, the lubricating oil has the advantages of favorable friction and wear resistance, environment friendliness and no pollution.

Description

A kind of lubricating oil containing Il/Mongolian clay nano-powder and its preparation method

technical field

The present invention relates to a lubricating oil containing nano-powder of Il/Mongolian clay and a preparation method thereof, in particular to a method of adding modified Il/Mongolian clay as an additive to class III base oils to improve the performance of class III base oils. A lubricating oil with anti-friction and wear properties and a preparation method thereof belong to the new application field of layered silicate clay minerals.

Background technique

The ever-changing machines and mechanical equipment require lubricating oils to adapt to various working conditions, such as high temperature, low temperature, vacuum, high radiation, high load and corrosive media, etc., and also require a long service life and storage stability etc. Therefore, it is difficult to meet these requirements by relying on the performance of the lubricating oil itself. Lubricating oil additives are one of the main ways to solve these problems. Compared with traditional lubricating oil additives, nano-scale additives are much higher than traditional lubricating oil additives in terms of oil film strength, suspension density and uniformity. Therefore, nano-lubricating additives are the main development trend of lubricating additives in the future.

Nano-lubricating additives can be divided into two categories: synthetic and natural according to their sources. Most of the synthesized nano-additives are compounds or simple substances of S, P, and Pb. These elements not only easily cause corrosion to the friction parts of metal workpieces, shorten the service life of workpieces, but also pollute the environment. At present, many scientific and technological workers apply natural mineral clay powder as an additive to lubricating oil (such as serpentine, bentonite, kaolinite, sepiolite, attapulgite, talc, pyrophyllite and secondary graphite, etc.), and obtained Some research results have been achieved, which mainly depends on the fact that these mineral particles belong to layered silicate minerals. These particles are deposited on the friction surface, preventing the direct contact between the friction workpieces, so that the friction only occurs between the layered structures of the minerals. space, thereby reducing friction and reducing wear. However, most of these mineral particles are at the micron level, so they cannot repair the cracks and micropores existing on the surface of the friction workpiece, resulting in an unsatisfactory anti-wear and anti-friction effect.

Contents of the invention

In view of the unsatisfactory anti-wear and anti-friction effect of existing lubricating oils, the object of the present invention is to provide a lubricating oil containing nano-powder of Il/Mongolian clay and a preparation method thereof, wherein the lubricating oil adopts Il/Mongolian clay As an additive, nano powder has good anti-friction and wear properties, and is environmentally friendly and pollution-free.

The purpose of the present invention is achieved by the following technical solutions:

A lubricating oil containing Il/Mongolian clay nano-powder, said lubricating oil is composed of oleic acid-modified Il/Mongolian clay nano-powder and type III base oil, wherein the oleic acid-modified Il/Mongolian clay nano-powder The powder accounts for 0.5-2.5% of the total mass of lubricating oil.

The preparation method of the lubricating oil containing Iraqi/Mongolian clay nano-powder of the present invention, the steps are as follows:

(1) Preparation of slurry: Mechanically crush the natural Iraqi/Mongolian clay minerals into small pieces of Iraqi/Mongolian clay minerals with a particle size of less than 5cm; soak the small pieces of Iraqi/Mongolian clay mines in water for 12 hours to obtain Iraqi/Mongolian clay materials Slurry; Wherein, slurry solid content is 45wt%;

(2) Dispersion: adjust the pH value of the Iraqi/Mongolian clay slurry to 9, add a dispersant, and use a sand mill disperser to disperse the slurry; wherein, the amount of the dispersant added is 1.5% of the solid content of the slurry. wt%; the rotating speed of the sand mill disperser is 1000rpm, and the stirring time is 30min;

(3) Screening: pass the slurry dispersed in step (2) through a 500-mesh sieve to obtain the under-screen slurry;

(4) Grinding: Grinding the under-screen slurry with a high-energy-density stirring mill, wherein the feeding speed of the pump is 3L/min, the grinding medium is _ZrO2 ceramic microbeads with a diameter of 0.4-0.6mm, and the filling rate of the grinding medium is 85%, the mill speed is 1400rpm, and the grinding time is 2-6h; after grinding, nano slurry is obtained;

(5) Modification: Move the slurry obtained in step (4) into a round bottom flask, add oleic acid under stirring, continue stirring for 40 minutes after adding oleic acid, then wash it with absolute ethanol for 3 times, and then use Washing with deionized water 3 times, wherein the addition of oleic acid is 4wt% of the solid content of the slurry; obtain the modified nano slurry;

(6) Drying: move the modified nano-slurry obtained in step (5) to a vacuum environment for drying, wherein the drying temperature is 60°C, and the drying time is 24 hours, to obtain a modified Il/Mongolian clay nano-dry powder;

(7) Mixing: Mix the modified I/M clay nano-dry powder obtained in step (6) with III base oil, and undergo ultrasonic dispersion and high-speed shear dispersion for 0.5 hours each to obtain the I/I-containing clay of the present invention. Clay nano-powder lubricating oil; the shear speed is 6000rpm; the modified Iraqi/Mongolian clay nano-dry powder accounts for 0.5-2.5% of the total mass of the lubricating oil, and the rest is Group III base oil;

Step (2) NaOH or _H2SO4 solution is preferably used when adjusting the pH value of the I/Mongolian clay slurry _;

The dispersant in step (2) is preferably WF-211 dispersant (polycarboxylate sodium salt copolymer).

Beneficial effect

The lubricating oil of the present invention adopts the Iraqi/Mongolian clay nano-powder as an additive, which has the following advantages:

(1) It has the characteristics of other types of layered silicate minerals as lubricating additives.

Yi/Mongolian clay nanopowder has a natural layered structure. This microscopic layered structure is more conducive to clay nanoparticles covering the surface of the friction workpiece, thereby preventing direct contact with the friction workpiece and making the friction only occur in the microscopic layer of mineral particles. Between the structures, thereby reducing friction and reducing wear.

(2) It has the characteristics of nano-particle lubricating additives, and is environmentally friendly and pollution-free.

As a lubricating oil additive, Iraqi/Mongolian clay nanopowder has the characteristics of nanoparticle additives, that is, ①it is beneficial to its stability and dispersion in lubricating oil, and enhances the storage stability of the prepared lubricating oil; ②due to the size effect of nanoparticles, it has It is helpful for the adsorption of particles on the surface of the friction workpiece; ③High chemical activity, which is conducive to the tribochemical reaction and the formation of a friction self-repairing protective film under high temperature and high pressure at the moment of friction; ④It is conducive to the filling of nanoclay particles in the cracks and In the micropores, the surface of the friction workpiece is repaired, the friction process is more stable, and it is easier to form a continuous and uniform self-repairing protective film on the surface of the friction workpiece.

Description of drawings

Fig. 1 is the cumulative particle distribution diagram of Examples 1-4; wherein, 2h-Example 1, 3h-Example 2, 4h-Example 3, 6h-Example 4;

Fig. 2 is the friction coefficient curve figure that contains Iraqi/Mongolian clay nano-powder lubricating oil described in embodiment 1～5;

Figure 3 is the 3D profile of the surface of the friction pair after friction when the content of I/Mongolian clay nanopowder is 0.0wt%.

Fig. 4 is a 3D profile diagram of the surface of the friction pair after friction when the content of the I/Mongolian clay nanopowder is 2.0wt%.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments, but is not limited thereto.

The equipment used in the following examples is as follows:

Sand mill dispersing machine: Shenzhen Sanxing Feirong Machinery Co., Ltd. SDF-400 type;

High energy density stirring mill: Swiss Bulher (Buhler) company SuperFlow12 type;

The Group III base oil used in the examples is 40# base oil produced by China Petrochemical Corporation.

The dispersant WF-211 used in the examples was produced by Shanghai Xinyang Chemical Co., Ltd.

Example 1

(1) Preparation of slurry: Mechanically crush natural I/Mongolian clay minerals into small pieces of I/Mongolian clay ore with a particle size of less than 5cm; mix 450g of I/Mongolian clay with 550g of water, and then soak for 12 hours to obtain I/Mongolian clay ore Mongolian clay slurry;

(2) Dispersion: Use 0.1mol/L NaOH solution to adjust the pH value of the Iraqi/Mongolian clay slurry to 9, add 6.75g of dispersant WF-211, and use a sand mill disperser for slurry dispersion; among them, the dispersant The addition of WF-211 is 1.5wt% of the solid content in the slurry; the speed of the sand mill disperser is 1000rpm, and the stirring time is 30min;

(3) Screening: pass the slurry dispersed in step (2) through a 500-mesh sieve to obtain the under-screen slurry;

(4) Grinding: Use a high energy density stirring mill to grind the underscreen slurry, where the feeding speed of the pump is 3L/min, the grinding medium is _ZrO2 ceramic microbeads with a diameter of 0.6mm, and the filling rate of the grinding medium is 85% , the mill speed is 1400rpm, and the grinding time is 2h; nano slurry is obtained after grinding; the particle cumulative distribution diagram of the slurry is shown in the 2h curve in Figure 1, and it can be seen that the particles less than 100nm account for about 64%, and the particles The particle size reaches nanometer level;

(5) Modification: Move the slurry obtained in step (4) into a round bottom flask, add 18g of oleic acid under stirring and continue stirring for 40 minutes, then wash with absolute ethanol for 3 times, and then wash with deionized water 3 times to obtain the modified nano slurry;

(6) Drying: Move the modified nano-slurry obtained in step (5) to a vacuum drying oven for drying at a drying temperature of 60°C and a drying time of 24 hours to obtain a modified Il/Mongolian clay nano-dry powder.

(7) Mixing: Take 1g of modified Il/Mongolian clay nano-dry powder and 199g of Group III base oil and mix them in a round-bottomed flask. After ultrasonic dispersion and high-speed shear dispersion for 0.5h each, Il/Mongolian clay can be prepared Nano powder mass fraction is 0.5wt% lubricating oil, wherein the shear rate is 6000rpm.

Example 2

The difference between this example and Example 1 is that the grinding time in step (4) is 3h, and the particle cumulative distribution diagram of the prepared nano-slurry is shown in the 3h curve in Figure 1, and it can be seen that the particles less than 100nm The particles accounted for about 67%, and the particle size reached the nanometer level; in step (7), 2g of the modified Il/Mongolian clay nanopowder and 198g of Group III base oil were taken to prepare the Il/Mongolian clay nanopowder with a mass fraction of 1.0 wt% lubricating oil.

Example 3

The difference between this example and Example 1 is that the grinding time in step (4) is 4h, and the particle cumulative distribution diagram of the slurry is shown in the 4h curve in Figure 1. It can be seen that the particles smaller than 100nm account for about 70%, and the particle size reaches nanoscale; in step (7), take 3g of modified Il/Mongolian clay nano-powder and 197g III base oil to prepare a 1.5wt% lubricating oil.

Example 4

The difference between this example and Example 1 is that the grinding time in step (4) is 6h, and the particle cumulative distribution diagram of the slurry is shown in the 6h curve in Figure 1. It can be seen that the particles smaller than 100nm account for about 72%, and the particle size reaches the nanoscale; in step (7), take 4g of the modified Il/Mongolian clay nanopowder and 196g of III base oil to prepare a 2.0wt% ethanol/Mongolian clay nanopowder containing lubricating oil.

Example 5

The difference between this example and Example 1 is that the grinding time in step (4) is 6 hours, and the grinding time in step (4) is 6 hours. From the particle cumulative distribution diagram of the slurry, it can be seen that the particles smaller than 100nm It accounts for about 72%, and the particle size reaches the nanometer level; in step (7), take 5g of the modified Il/Mongolian clay nanopowder and 194g of Group III base oil, and prepare the Il/Mongolian clay nanopowder with a mass fraction of 2.5wt % lubricating oil.

The friction performance of the lubricating oil in Examples 1 to 5 was tested using an MRS-10A four-ball friction tester, and the test data are shown in Figures 2, 3 and 4. Friction steel balls are standard secondary steel balls (GCr15, Φ12.7mm, HRC59-61, w(Fe): 96.50-97.49%; w(C): 0.95-1.05%; w(Si): 0.15-0.35%; w(Cr): 1.30-1.65%; w(Mn): 0.20-0.40%; w(S): ≤0.02%; w(P): ≤0.027%); the experimental conditions are: experimental load 400N, speed 1450rpm, The friction time is 60min.

Fig. 2 has shown the friction coefficient curve chart containing different mass fractions of I/Mongolian clay nanopowder lubricating oil in each embodiment. Compared with the lubricating oil without I/Mongolian clay nano-powders, the average friction coefficient of lubricating oil containing I/Mongolian clay nano-powders is reduced to varying degrees; especially when the content is 2.0wt%, the average friction coefficient The lowest (0.030), decreased by 60% (0.075→0.030), which shows that the I/Mon clay nanopowder has good anti-friction and wear properties as a lubricating additive.

Figure 3 is the 3D profile of the surface of the friction pair after the friction steel ball is rubbed when the content of the I/Mongolian clay nano-powder is 0.0wt%, that is, no I/Mongolian clay nano-powder is added; When the powder content is 2.0wt%, the 3D contour map of the surface of the friction pair after the friction steel ball is rubbed. It can be seen from the figure that compared with the lubricating oil without I/Mongolian clay nano-powder, the friction steel ball lubricated by the lubricating oil containing Il/Mongolian clay nano-powder has better surface flatness, shallow furrow, The roughness is small (446.94nm→201.07nm), which shows that the Il/Mongolian clay nanopowder has a good ability to improve the friction contact surface.

The present invention includes but is not limited to the above embodiments, and any equivalent replacement or partial improvement under the principle of the spirit of the present invention will be considered within the protection scope of the present invention.

Claims (3)

1. A preparation method of lubricating oil containing Il/Mongolian clay nano-powder, characterized in that, said lubricating oil is composed of Il/Mongolian clay nano-powder and class III base oils modified by oleic acid, wherein, oil Acid-modified Il/Mongolian clay nano-powder accounts for 0.5~2.5% of the total mass of lubricating oil; The preparation method steps are as follows: (1) Preparation of slurry: mechanically crush natural I/Mongolian clay minerals into small pieces of I/Mongolian clay minerals with a particle size of less than 5 cm; soak the small pieces of I/Mongolian clay ore in water for 12 h to obtain I/Mongolian clay minerals Clay slurry; Wherein, slurry solid content is 45 wt%; (2) Dispersion: adjust the pH value of the Iraqi/Mongolian clay slurry to 9, add a dispersant, and use a sand mill disperser to disperse the slurry; wherein, the amount of the dispersant added is 1.5% of the solid content of the slurry. wt%; the rotating speed of the sand mill disperser is 1000 rpm, and the stirring time is 30 min; (3) Screening: pass the slurry dispersed in step (2) through a 500-mesh sieve to obtain the under-screen slurry; (4) Grinding: Grinding the underscreen slurry with a high-energy-density stirring mill, wherein the feeding speed of the pump is 3 L/min, the grinding medium is ZrO ₂ ceramic microbeads with a diameter of 0.4-0.6 mm, and the filling rate of the grinding medium is is 85%, the mill speed is 1400 rpm, and the grinding time is 2~6 h; nano slurry is obtained after grinding; (5) Modification: move the slurry obtained in step (4) into a round bottom flask, add oleic acid under stirring, continue stirring for 40 min after adding oleic acid, then wash with absolute ethanol for 3 times, and then Wash 3 times with deionized water, wherein the oleic acid addition is 4 wt% of the solid content of the slurry; obtain the modified nano slurry; (6) Drying: move the modified nano-slurry obtained in step (5) to a vacuum environment for drying, wherein the drying temperature is 60° C., and the drying time is 24 h to obtain a modified Il/Mongolian clay nano-dry powder; (7) Mixing: Mix the modified Il/Mongolian clay nano dry powder obtained in step (6) with Group III base oil, and undergo ultrasonic dispersion and high-speed shear dispersion for 0.5 h each to obtain the Il/Mongolian clay nanometer powder. Powder lubricating oil; the shear speed is 6000 rpm; the modified Iraqi/Mongolian clay nano-dry powder accounts for 0.5~2.5% of the total mass of the lubricating oil, and the rest is Group III base oil. 2. The method for preparing lubricating oil containing Il/Mongolian clay nanopowder according to claim 1, characterized in that NaOH or H ₂ SO ₄ solution is used when adjusting the pH value of the Il/Mongolian clay slurry in step (2) . 3. The preparation method of lubricating oil containing illite/mongolin clay nano-powder according to claim 1, characterized in that the dispersant in step (2) is WF-211 dispersant.