CN113913232A - Energy-saving low-ash long-oil-change-period diesel engine oil and preparation method and application thereof - Google Patents

Abstract

The invention relates to the technical field of diesel engine oil, in particular to energy-saving low-ash long-oil-change-period diesel engine oil and a preparation method and application thereof. The diesel engine oil comprises the following components in parts by weight: 70-80 parts of base oil, 15-30 parts of engine oil complexing agent, 1-5 parts of OCP (epoxy-modified Polypropylene) type viscosity index improver and 0.1-0.5 part of PMA (polymethyl acrylate) type pour point depressant; 0.1-1.5 parts of molybdenum dialkyl dithiocarbamate. The diesel engine oil meets the specification requirement of API FA-4, has the advantages of low sulfated ash content, ultra-long oil change period, low friction coefficient, excellent energy-saving effect, excellent low-temperature performance, high viscosity index, strong high-temperature oxidation resistance and the like, can effectively ensure the normal operation of the national six-diesel engine, and can effectively improve the fuel economy of the diesel engine while protecting the engine.

Description

Energy-saving low-ash long-oil-change-period diesel engine oil and preparation method and application thereof

Technical Field

The invention relates to the technical field of diesel engine oil, in particular to energy-saving low-ash long-oil-change-period diesel engine oil and a preparation method and application thereof.

Background

In recent years, in order to solve the increasingly prominent problem of air pollution, the emission standard of vehicle pollutants is upgraded for many times, and especially, stricter requirements on the emission of particulate matters and nitrogen oxides are provided, and the aftertreatment technology of the diesel engine is continuously developed. At present, with the innovation of engine technology and the gradual implementation of six emission regulations in China, OEM manufacturers upgrade filling oil and after-sales oil thereof in many times, and require diesel engine oil with low ash content and long oil change period.

In addition, with the increasingly stringent requirements for energy conservation and emission reduction of vehicles, the energy conservation requirements of domestic and foreign commercial vehicles for lubricating oil products will become a trend and a normal state in the future. In recent decades, researchers have found that there are two main ways to improve the fuel economy of internal combustion engines: firstly, properly reducing the kinematic viscosity and the high-temperature high-shear viscosity of the lubricating oil; and secondly, the friction loss generated by the friction of the engine is reduced. Therefore, the use of high-performance low-viscosity lubricating oils and the addition of friction modifiers has become a trend in the development of lubricating oils. Based on this, the American Petroleum Institute (API) issued a new generation of diesel engine oil specification FA-4 with energy saving requirements in 2016.

Because the working conditions of the diesel engine are harsh, the requirement on the oil film strength of the engine oil is higher than that of a gasoline engine, and the requirement on the viscosity-temperature performance of the engine oil is higher. Therefore, the development of diesel engine oil which can meet the requirements of commercial vehicle OEM energy saving and pollutant emission environmental protection standards while ensuring the lubricating performance and durability and reliability is urgently needed.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention aims to provide the energy-saving diesel engine oil with low viscosity, high viscosity-temperature performance, low friction coefficient, low sulfated ash content and long oil change period, and the preparation method and the application thereof.

In order to achieve the purpose, the technical scheme of the invention is as follows:

different from gasoline engines, diesel engines are mostly required to be used under high load in a low-temperature environment, so that higher requirements are provided for the viscosity-temperature performance, the friction reduction performance and the energy-saving performance of engine oil. In the prior art, the performance of the diesel engine oil is improved by adding a functional additive of inorganic salt containing sulfur and phosphorus; in order to improve the oxidation resistance and prolong the oil change period, phenolic antioxidants and amine antioxidants are added, and although the performance of the diesel engine oil can be obviously improved by adding the functional additives, the diesel engine oil has large influence on the environment, so that the diesel engine oil is difficult to meet the high-standard environmental protection quality requirement; however, the removal of the functional additives reduces the key performance of the diesel engine oil. According to the invention, through a large amount of research and development and practice, the OCP type viscosity index improver and the PMA (polymethacrylate) type pour point depressant are compounded for use, and meanwhile, the molybdenum dialkyl dithiocarbamate is added, so that the energy-saving performance and the viscosity-temperature performance of the diesel engine oil can be obviously improved, the shear stability of the oil product is effectively maintained, and the oil change period of the oil product is prolonged.

Specifically, the technical scheme of the invention is as follows:

the invention provides energy-saving low-ash long-oil-change-period diesel engine oil which comprises the following components in parts by weight: 70-80 parts of base oil, 15-30 parts of engine oil complexing agent, 1-5 parts of viscosity index improver and 0.1-0.5 part of pour point depressant; wherein the viscosity index improver is an OCP type viscosity index improver; the pour point depressant is a PMA type pour point depressant; the diesel engine oil also includes a friction modifier comprising molybdenum dialkyldithiocarbamate (MoDTC).

The MoDTC has the following structural general formula:

in the formula, R₁～R₄Is C₄～C₁₈The linear or branched alkyl or alkenyl group of (3).

The MoDTC is a commercial product.

The ethylene propylene copolymer (OCP) is used as the viscosity index improver, the viscosity index improver has the characteristics of excellent shear stability, good effect of improving the viscosity index of an oil product and good oxidation stability, and is compounded with the PMA pour point depressant on the basis, and the combination of the ethylene propylene copolymer (OCP) and the PMA pour point depressant can well ensure the condensation point, viscosity and viscosity-temperature performance of engine oil. Meanwhile, MoDTC is added as a friction modifier, has the advantages of excellent wear-resistant and friction-reducing performance, extreme pressure performance superior to that of molybdenum disulfide, high decomposition temperature, no phosphorus element (phosphorus can cause the catalyst in an automobile exhaust catalytic converter to be poisoned and failed) and the like, can be ideally compounded with an OCP type viscosity index modifier, effectively reduces the viscosity and the friction coefficient of engine oil, improves the energy-saving effect of the engine oil, has higher oxidation resistance, and can effectively prolong the oil change period.

The sulfated ash content of the diesel engine oil is less than or equal to 1.0 percent; the diesel engine oil meets API FA-4 specification requirements, and viscosity grades include, but are not limited to, 5W-30 viscosity grades.

In order to better improve the energy-saving property and the viscosity-temperature property of the diesel engine oil, the shear stability index SSI of the OCP type viscosity index improver is preferably less than 25.

More preferably, in the diesel engine oil, the mass ratio of the OCP type viscosity index improver to the PMA type pour point depressant is (6-10): 1. by adopting the proportion for compounding, the energy-saving property and the viscosity-temperature property of the diesel engine oil can be better improved.

The viscosity of the diesel engine oil is 9.3-12.5 mm²S, viscosity index>160，150℃、10⁶s^-1The high-temperature high-shear viscosity of the polycarbonate is 2.9 to 3.2 mPas.

In the invention, the OCP type viscosity index improver can be a product produced by Chevrolet and other companies, and is preferably a mixture of one or more of Paraton 24Ex, Paraton 35Ex and LZ 7067.

In the invention, the PMA pour point depressant is preferably poly-tetradecyl methacrylate, and products produced by the companies of Wingchuang Texaco, Ruiyinglian, Chevrolet and the like can be selected.

Preferably, the weight part content of the molybdenum dialkyl dithiocarbamate in the diesel engine oil is 0.1-1.5 parts. By adopting the proportion, the energy-saving property of the diesel engine oil can be ensured while the low ash content is ensured.

The MoDTC is added into the diesel engine oil in an additional mode, namely: firstly, preparing the engine oil complexing agent, the viscosity index improver, the base oil and the pour point depressant into a mixture, and then adding the molybdenum dialkyl dithiocarbamate for mixing.

For better coordination with the above functional additives, the base oil is preferably any one of group III base oil, PAO base oil or a mixture of two.

The group III base oil and PAO base oil are commercially available products, and can be selected from group III and PAO base oils produced by companies such as medium petrochemical, medium petroleum, Petronas, S-oil, Mobil, Korea SK, etc.

More preferably, the base oil is a group III base oil; the kinematic viscosity at 100 ℃ of the III base oil is 3.9-6.4 mm²Per s and viscosity index>120。

The engine oil complexing agent disclosed by the invention is preferably a diesel engine oil complexing agent meeting the specification requirement of API FA-4.

In the diesel engine oil compound agent meeting the specification requirement of API FA-4, one of H12210, OLOA 61530, OLOA 61105 and CV1103 is preferably selected to be better compounded with an OCP type viscosity index improver, a PMA type pour point depressant and a friction modifier.

Preferably, the diesel engine oil comprises the following components in parts by weight: 75-80 parts of III base oil, 15-25 parts of engine oil complexing agent meeting API FA-4 specification requirements, 2-5 parts of OCP type viscosity index improver, 0.2-0.4 part of PMA type pour point depressant and 0.1-1.5 parts of molybdenum dialkyl dithiocarbamate.

Further, the invention also provides a preparation method of the diesel engine oil, which comprises the following steps:

(1) preparing the base oil, an engine oil complexing agent, a viscosity index improver and a pour point depressant into a mixture according to a proportion;

(2) heating the mixture obtained in the step (1) to 55 ℃, adding the friction modifier into the mixture in an additional mode, and stirring for 2-10 hours at the temperature of 50-70 ℃.

The invention further provides application of the diesel engine oil in a diesel engine.

The invention has the beneficial effects that:

the diesel engine oil disclosed by the invention meets the specification requirement of API FA-4, has the potential of meeting the specification of ACEA F11, has the characteristic of low sulfated ash, can be well coordinated and matched with each other, and shows excellent durability, oxidation resistance, antifriction performance, energy-saving performance and viscosity-temperature performance. The simulation test and the driving test prove that: the diesel engine oil disclosed by the invention can effectively guarantee the normal operation of a national six-diesel engine, has the advantages of an ultra-long oil change period (up to 10 kilometers), ultra-low sulfate ash content, low friction coefficient, excellent energy-saving effect, excellent low-temperature performance, high viscosity index and strong high-temperature oxidation resistance, and can effectively improve the fuel economy of the diesel engine while efficiently protecting the engine.

Drawings

Fig. 1 is an experimental result of verifying the energy saving performance of diesel engine oil by using a friction and wear tester in experimental example 2 of the present invention.

Detailed Description

Preferred embodiments of the present invention will be described in detail with reference to the following examples. It is to be understood that the following examples are given for illustrative purposes only and are not intended to limit the scope of the present invention. Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the spirit and scope of this invention.

The experimental procedures used in the following examples are all conventional procedures unless otherwise specified.

Materials, reagents and the like used in the following examples are commercially available unless otherwise specified. The FA-4 engine oil complex agent A and the FA-4 engine oil complex agent B are engine oil complex agents which are produced by Chevrolet Auranty and can support the FA-4 specification, the OCP type viscosity index improver is produced by Chevrolet Auranty, the PMA type pour point depressant is produced by Wiegungsa, the MoDTC is produced by Idekco, and the III type base oil is produced by Korea SK.

The preparation method of the diesel engine oil in the following examples is as follows: preparing a mixture of base oil, an engine oil complexing agent, a viscosity index improver and a pour point depressant according to a proportion, heating the mixture to 55 ℃, starting a stirring device, then slowly adding MoDTC into the stirred mixture in an external mode, and then stirring for 2 hours at the temperature of 55 ℃ in a heating reaction kettle to prepare the diesel engine oil.

Example 1

The embodiment provides energy-saving low-ash long-oil-change-period diesel engine oil which comprises the following components in percentage by weight:

example 2

The embodiment provides energy-saving low-ash long-oil-change-period diesel engine oil which comprises the following components in percentage by weight:

example 3

The embodiment provides energy-saving low-ash long-oil-change-period diesel engine oil which comprises the following components in percentage by weight:

example 4

The embodiment provides energy-saving low-ash long-oil-change-period diesel engine oil which comprises the following components in percentage by weight:

example 5

The embodiment provides energy-saving low-ash long-oil-change-period diesel engine oil which comprises the following components in percentage by weight:

example 6

The embodiment provides energy-saving low-ash long-oil-change-period diesel engine oil which comprises the following components in percentage by weight:

comparative example 1

This comparative example provides a diesel engine oil which differs from example 4 only in that no MoDTC was added.

Comparative example 2

This comparative example provides a diesel engine oil which differs from example 6 only in that no MoDTC was added.

Experimental example 1 running test

The running test of the energy-saving, low-ash and long-oil-change-period diesel engine oil of the embodiment 1-6 is carried out by the following specific method:

five domestic most representative heavy commercial vehicles of OEM brands are selected, the working condition is the high-speed road condition from the middle coastal area to the south area, the engine is a national V emission engine, and the fuel oil is national V vehicle diesel oil of a normal gasoline station. In the driving test, each vehicle is subjected to a 20-kilometre driving test (10 kilometres per wheel and two wheels in total), the total mileage of the test is one kilometre, each kilometre is sampled, and the oil change index is specified by an OEM (original equipment manufacturer).

And (3) test results: the average oil change period of five trolleys is 10.2 kilometres, and the test disassembly score and sample detection data show that the engine oil of the embodiments 1 to 6 has excellent oxidation resistance and alkali value retention capacity and meets the requirement of 10 kilometres long oil change period. Furthermore, by examining the fuel consumption of five test vehicles and comparing with the vehicle using the oil of comparative example 1, the average energy saving efficiency was found to be 2.55%.

Experimental example 2 verification of Engine oil Performance

To further verify the performance of the energy-saving, low ash, long drain intervals diesel engine oils of examples 1-6, the compositional composition, energy-saving performance, viscosity-temperature performance, and oxidation resistance of the engine oils were separately verified.

The subjects were as follows:

experimental group 1: the energy-efficient, low ash, long drain interval diesel engine oil of example 4;

experimental group 2: the energy-efficient, low ash, long drain interval diesel engine oil of example 6;

control group 1: the diesel engine oil of comparative example 1;

control group 2: the diesel engine oil of comparative example 2.

1. Laboratory formulation analysis of engine oils

The physicochemical data of each experimental object all meet the specification requirement of API FA-4, the detection results of the molybdenum element content and the sulfated ash content are shown in Table 1, and as can be seen from Table 1, the sulfated ash content of the two experimental groups is the same as that of the two control groups, which shows that the diesel engine oil of the embodiment 4 and the embodiment 6 has no influence on the sulfated ash content while the energy-saving effect of the oil product is improved (the molybdenum content is increased).

TABLE 1 laboratory formulation analysis of engine oils

Element content	Experimental group 1	Control group 1	Experimental group 2	Control group 2
					Molybdenum content (mass fraction)%	0.0788	0.0080	0.0775	0.0067
Sulfated ash (mass fraction)%	1.0	1.0	1.0	1.0

2. Energy saving performance

Using a system introduced from OPTIMOL of Germany

The energy-saving performance of the diesel engine oil is verified by a type 4 friction wear testing machine.

The test conditions were as follows:

temperature: 80 ℃, load: 200N, frequency: 50Hz, amplitude: 1.0mm, run length: and (4) 1 h.

The experimental group and the control group were analyzed under the above test conditions, and the results are shown in table 2 and fig. 1.

TABLE 2 energy saving Properties of Diesel Engine oils

Group of	Experimental group 1	Experimental group 2	Control group 1	Control group 2
					Average coefficient of friction	0.042	0.044	0.094	0.099
Energy saving effect	★★★	★★★	★	★

The experimental results show that the friction coefficient of the engine oils of the two experimental groups is reduced by more than 50% compared with that of the two control groups, which shows that the diesel engine oils of examples 4 and 6 have very excellent energy-saving effect.

3. Viscosity-temperature property

The viscosity-temperature performance of the energy-saving low-ash long-oil-change-period diesel engine oil of the embodiment is evaluated by adopting indexes such as kinematic viscosity at 100 ℃, viscosity index, low-temperature dynamic viscosity, low-temperature pumping viscosity and the like. Kinematic viscosity is an index which reflects the magnitude of the internal friction of an oil product and represents the oiliness and the fluidity of the oil product. The viscosity index reflects the degree of the oil viscosity changing along with the temperature, and the higher the viscosity index is, the smaller the influence of the temperature on the viscosity is, and the better the viscosity-temperature property is. The low-temperature dynamic viscosity is closely related to the starting performance of the engine at low temperature, and if the engine oil is too viscous at the starting temperature, the moving parts are viscous, so that the crankshaft of the engine cannot rotate to reach the specified rotating speed and cannot be started. The low-temperature pumping viscosity reflects the capability of engine oil to be continuously and fully supplied to an oil pump inlet at low temperature, and the phenomenon of air entrainment and evacuation is easily caused when the viscosity is too high, so that the oil cannot flow to the pump inlet, and the starting abrasion is caused. The results of the experiment are shown in table 3.

TABLE 3 viscosity temperature Performance of Diesel Engine oils

As can be seen from table 3, the viscosity temperature performance of the two experimental groups was very close to that of the two control groups, indicating that the viscosity temperature performance of the engine oil was not affected by the addition of MoDTC; the viscosity index of the diesel engine oil of the embodiment 4 and the embodiment 6 can reach more than 150, which shows that the engine oil has excellent viscosity-temperature performance and excellent low-temperature starting performance, can effectively reduce starting abrasion, and can better protect the engine.

4. Antioxidant property

The oxidation resistance of the diesel engine oils of the examples was evaluated using the lubricating oil oxidation test (PDSC). The method judges the antioxidant ability of the engine oil by measuring the amount of deposits formed, and the results are shown in table 4.

TABLE 4 Oxidation resistance of Diesel Engine oils

The results show that the oxidation induction period of the diesel engine oils of the two experimental groups is significantly higher than that of the two control groups, indicating that the engine oils of examples 4 and 6 have very good antioxidant properties.

Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims (10)

1. An energy-saving, low-ash and long-oil-change-period diesel engine oil is characterized by comprising the following components in parts by weight: 70-80 parts of base oil, 15-30 parts of engine oil complexing agent, 1-5 parts of viscosity index improver and 0.1-0.5 part of pour point depressant;

the viscosity index improver is an OCP type viscosity index improver; the pour point depressant is a PMA type pour point depressant;

the diesel engine oil further comprises a friction modifier comprising molybdenum dialkyl dithiocarbamate.

2. The diesel engine oil of claim 1, characterized by having a sulfated ash of 1.0% or less; the diesel engine oil meets API FA-4 specification requirements, and viscosity grades include 5W-30 viscosity grades.

3. The diesel engine oil according to claim 1 or 2, characterized in that the viscosity index improver of the OCP type has a shear stability index SSI < 25;

preferably, in the diesel engine oil, the mass ratio of the OCP type viscosity index improver to the PMA type pour point depressant is (6-10): 1.

4. the diesel engine oil according to any one of claims 1 to 3, wherein the viscosity of the diesel engine oil is 9.3 to < 12.5mm²S, viscosity index>160，150℃、10⁶s^-1The high-temperature high-shear viscosity of the polycarbonate is 2.9 to 3.2 mPas.

5. The diesel engine oil according to any one of claims 1 to 4, wherein the molybdenum dialkyldithiocarbamate is contained in an amount of 0.1 to 1.5 parts by weight.

6. The diesel engine oil according to any one of claims 1 to 5, wherein the base oil is any one of group III base oil and PAO base oil or a mixture of two of them;

preferably, the base oil is a group III base oil; the kinematic viscosity at 100 ℃ of the III base oil is 3.9-6.4 mm²Per s and viscosity index>120。

7. The diesel engine oil as set forth in any one of claims 1 to 6, wherein the engine oil complex is a diesel engine oil complex that meets the API FA-4 specification.

8. The diesel engine oil according to any one of claims 1 to 7, comprising the following components in parts by weight: 75-80 parts of III base oil, 15-25 parts of engine oil complexing agent meeting API FA-4 specification requirements, 2-5 parts of OCP type viscosity index improver, 0.2-0.4 part of PMA type pour point depressant and 0.1-1.5 parts of molybdenum dialkyl dithiocarbamate.

9. The method for producing a diesel engine oil according to any one of claims 1 to 8, characterized by comprising the steps of:

(1) preparing the base oil, the engine oil complexing agent, the viscosity index improver and the pour point depressant into a mixture according to a proportion;

(2) heating the mixture obtained in the step (1) to 55 ℃, adding the friction modifier into the mixture in an additional mode, and stirring for 2-10 hours at the temperature of 50-70 ℃.

10. Use of the diesel engine oil of any one of claims 1 to 8 in a diesel engine.

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