Oxidized paraffin and antirust wax and preparation method thereof

Abstract

The invention discloses oxidized paraffin and antirust wax and a preparation method thereof, and relates to the field of paraffin. The antirust wax comprises oxidized paraffin, an emulsifier, an antirust agent and water, and the emulsifier is at least one of sorbitan monooleate, lauryl sodium sulfate and fatty alcohol-polyoxyethylene ether; the antirust agent is at least one of cyclohexylamine stearate, alkenyl succinic acid and alpha-mercaptobenzothiazole; the oxidized paraffin is loaded with a Mn metal element through a carrier. The catalyst loaded with the active component Mn is added in the preparation process of the oxidized paraffin, the acid value and the soap value of the oxidized paraffin are effectively increased, the oxidized paraffin interacts with the specific emulsifier and the antirust agent, the emulsifier does not affect the anti-oxidation protection function of functional components, and meanwhile, the antirust agent and the oxidized paraffin cooperate with each other to achieve the anti-corrosion effect in a synergistic mode; and the antirust capability of metal in a humid and hot environment and an acid-base environment is improved, and the application prospect is expanded.

Description

Technical Field

[0001] This invention relates to the field of paraffin wax, and more particularly to an oxidized paraffin wax and a rust-preventive wax, and a method for preparing the same. Background Technology

[0002] my country is the world's largest producer of paraffin wax, but for many years, most of its paraffin wax has been used as a primary product. With technological advancements, the chemical modification of paraffin wax has attracted significant attention, as this modification can improve its performance and impart new properties. Among chemical modifications, the oxidation modification of paraffin wax plays a crucial role in the petrochemical industry. Oxidized paraffin wax is an oxide product obtained by oxidizing paraffin wax or oil-containing waxes under a certain catalyst using pure oxygen or air. Through oxidation modification, groups such as -OH, -COOH, -C=O-, and -COOR are introduced, fundamentally improving its affinity, emulsification, solubility, and lubricity. The emergence of oxidized paraffin wax has created new avenues for the further development of many industries. Further processing of oxidized paraffin wax can further improve its performance, increase the added value of oxidized paraffin wax products, and create greater economic benefits.

[0003] With the rapid development of my country's automobile manufacturing industry and the increasing number of cars on the road, China has become the most important production and sales market for domestic and foreign automakers, and a major stage for the automotive industry. During vehicle use, corrosion occurs, causing significant economic losses. Corrosion in the crevices of internal cavities is the most important cause of vehicle damage; therefore, developing automotive rust-preventive waxes based on oxidized paraffin is of great significance. Summary of the Invention

[0004] This invention provides an oxidized paraffin and a rust-preventive wax, and a method for preparing the same. A catalyst loaded with a metal active component is used to increase the acid value and saponification value of the oxidized paraffin, which is then applied to the rust-preventive wax to improve its anti-corrosion effect on metal objects.

[0005] To address the aforementioned technical problems, one objective of this invention is to provide a method for preparing oxidized paraffin, comprising the following steps: (1) After dissolving the metal salt in water, a carrier is added, the mixture is mixed and allowed to stand for a period of time, then dried and subsequently calcined to obtain a catalyst; the metal element of the metal salt includes Mn; (2) After heating and stirring the paraffin to dissolve it, a catalyst is added and air is continuously introduced to carry out oxidation treatment. After cooling, oxidized paraffin is obtained.

[0006] This application improves the catalytic oxidation activity by loading the catalyst with the active component Mn during the preparation of oxidized paraffin. After the catalyst is combined with paraffin, it is calcined together, which not only improves the acid value and soap value of the oxidized paraffin and gives it a high antioxidant capacity, but also makes the applied rust-preventive wax have excellent anti-corrosion performance, meeting the rust prevention requirements of salt spray test and damp heat test, and has great application prospects.

[0007] In some embodiments, in step (1), the metal salt further includes an auxiliary metal element, which is Co and / or Ce, and the mass ratio between the Mn-containing metal salt and the metal salt containing the auxiliary metal element is (1-3):1.

[0008] The metal salts loaded on the catalyst in this application have a significant impact on the acid value and soap value. By simultaneously loading Mn and Co or Ce, the catalytic oxidation activity can be improved, which can further increase the acid and ester values ​​and soap value of oxidized paraffin, improve its antioxidant capacity, and provide excellent anti-corrosion function when applied as an anti-rust wax. It can meet the anti-rust requirements in both humid and acidic / alkaline environments.

[0009] In some embodiments, the Mn-containing metal salt is at least one of MnSO4, Mn(NO3)2, and MnCl2.

[0010] In some embodiments, the Co-containing metal salt is CoCl2 and / or Co(NO3)2.

[0011] In some embodiments, the Ce-containing metal salt is Ce(NO3)3.

[0012] In some embodiments, in step (1), all the metal elements of the metal salt account for 10%-30% of the carrier mass.

[0013] In some embodiments, the carrier is at least one of ZSM-5, SBA-15, MCM-41, Al2O3, and SiO2.

[0014] In some implementations, in step (1), the mixing time is 1-3 h and the settling time is 6-10 h.

[0015] In some embodiments, in step (1), the drying temperature is 60-110 °C and the time is 7-12 h.

[0016] In some embodiments, in step (1), the calcination temperature is 300-500 °C and the time is 2-5 h.

[0017] In some embodiments, in step (2), the catalyst accounts for 0.5%-2% of the mass fraction of paraffin.

[0018] In some embodiments, in step (2), the volumetric hourly space velocity of the introduced air is 0.5-1.2 h⁻¹. -1 .

[0019] In some embodiments, in step (2), the oxidation treatment temperature is 120-190 °C and the time is 1-9 h.

[0020] To address the aforementioned technical problems, one objective of this invention is to provide an oxidized paraffin prepared using the above-described preparation method.

[0021] To address the aforementioned technical problems, a third objective of this invention is to provide a rust-preventive wax comprising oxidized paraffin wax, an emulsifier, a rust inhibitor, and water. The emulsifier is at least one of sorbitan monooleate, sodium dodecyl sulfate, and fatty alcohol polyoxyethylene ether. The rust inhibitor is at least one of cyclohexylamine stearate, alkenyl succinic acid, and α-mercaptobenzothiazole.

[0022] The rust-preventive wax of this application uses oxidized paraffin wax with high acid value and saponification value, which can provide effective antioxidant effect. After being applied to the rust-preventive wax, it interacts with specific emulsifiers and rust inhibitors. The emulsifier helps the components to be evenly dispersed without affecting the antioxidant protection function of the oxidized paraffin wax and the rust inhibitor. The specific rust inhibitor, in combination with the oxidized paraffin wax, can synergistically exert the anti-corrosion effect and improve the rust prevention ability of metals in humid and hot environments as well as acid and alkaline environments.

[0023] In some embodiments, the mass ratio of the oxidized paraffin to the emulsifier is 10:(4-9).

[0024] In some embodiments, the mass ratio of the oxidized paraffin to the rust inhibitor is 10:(5-15).

[0025] In some embodiments, the total amount of the oxidized paraffin, emulsifier, and rust inhibitor accounts for 20%-70% of the water mass fraction.

[0026] To solve the above-mentioned technical problems, the fourth objective of this invention is to provide a method for preparing rust-preventive wax, comprising the following steps: mixing the oxidized paraffin wax, emulsifier, rust inhibitor and water, stirring and mixing at a temperature of 60-150 °C for 10-80 min, and then cooling to obtain rust-preventive wax.

[0027] Compared with the prior art, the present invention has the following beneficial effects: In the preparation of oxidized paraffin, this application loads the catalyst with the active component Mn to enhance the catalytic oxidation activity, resulting in oxidized paraffin with higher acid value and soap value. This improves the antioxidant and rust-preventive effect of the rust-preventive wax. Furthermore, it interacts with specific emulsifiers and rust inhibitors. The emulsifiers help the components to disperse evenly without affecting the antioxidant and protective functions of the oxidized paraffin and rust inhibitors. The rust inhibitors and oxidized paraffin work synergistically to exert an anti-corrosion effect, improving the rust prevention ability of metals in humid and hot environments as well as acidic and alkaline environments, thus expanding the application prospects. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0029] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0030] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0031] As used in this article: In these embodiments, unless otherwise specified, the portions and percentages are all by weight.

[0032] "And / or" is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0033] In the description of this invention, it should be understood that the terms "upper", "lower", "left", "right", "top", "bottom", etc., indicating orientation or positional relationship are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0034] To further illustrate the present invention, the following detailed description is provided in conjunction with embodiments, but these should not be construed as limiting the scope of protection of the present invention. Unless otherwise specified, the raw materials used in the following embodiments and comparative examples are all commercially available, and the same raw materials were used in parallel experiments.

[0035] Example 1 A rust-preventive wax comprises 10 kg of oxidized paraffin, 4 kg of emulsifier, 8 kg of rust inhibitor and 36 kg of water, wherein the emulsifier is sorbitan monooleate (Span80) and the rust inhibitor is cyclohexyl stearate.

[0036] The above-mentioned method for preparing an anti-rust wax includes the following steps: (1) After dissolving the metal salt in water of equal mass, add the mesoporous molecular sieve MCM-41. The metal salt includes MnSO4 and Ce(NO3)3 in a mass ratio of 2:1. The total metal element of the metal salt accounts for 20% of the mass fraction of MCM-41. After mixing and stirring for 2 h, let stand for 8 h, filter, dry in an oven at 100 ℃ for 10 h, and then calcine in a muffle furnace at 300 ℃ for 2 h to obtain the catalyst. (2) Place 20 kg of 58# fully refined paraffin wax in a flask, heat and stir to dissolve, add a catalyst with a mass fraction of 0.7% of paraffin wax, and continuously purge air into the flask with an air hourly space velocity of 1 h⁻¹. -1 The mixture was oxidized at 145 °C for 2 h, and after cooling, oxidized paraffin was obtained. (3) Add oxidized paraffin, emulsifier, water and rust inhibitor to the reaction vessel, stir and mix at 85 °C for 50 min, and obtain rust-inhibiting wax after cooling.

[0037] Examples 2-5 A rust-preventive wax is prepared in the same way as Example 1, with the same steps, reagents, equipment and process parameters. The difference is that the metal salt is different in step (1), as shown in Table 1 below.

[0038] Examples 6-7 A rust-preventive wax is prepared in the same way as Example 1, with the same steps, reagents, equipment and process parameters. The difference is that the content of emulsifier is different in step (1), as shown in Table 1 below.

[0039] Examples 8-9 A rust-preventive wax is prepared in the same way as Example 1, with the same steps, reagents, equipment and process parameters. The difference is that the content of the rust inhibitor is different in step (1), as shown in Table 1 below.

[0040] Examples 10-11 A rust-preventive wax is prepared in the same way as Example 1, with the same steps, reagents, equipment and process parameters. The difference is that the rust inhibitor and emulsifier are different in step (1), as shown in Table 1 below.

[0041] Comparative Examples 1-8 A rust-preventive wax is prepared in the same way as Example 1, with the same steps, reagents, equipment and process parameters. The difference is that the metal salt is different in step (1), as shown in Table 1 below.

[0042] Comparative Example 9 A rust-preventive wax, the preparation method of which is the same as that of Example 1 in terms of each step, reagents, equipment and process parameters used in each step, except that no catalyst is added in step (2).

[0043] Comparative Example 10 A rust-preventive wax is prepared in the same way as Example 1, with the same steps, reagents, equipment and process parameters. The difference is that the emulsifier is different in step (1), as shown in Table 1 below.

[0044] Comparative Examples 11-12 A rust-preventive wax is prepared in the same way as Example 1, with the same steps, reagents, equipment and process parameters. The difference is that the rust inhibitor is different in step (1), as shown in Table 1 below.

[0045] Table 1 - Components and contents of oxidized paraffin and anti-rust wax in the embodiments and comparative examples of this application. Performance testing 1. Oxidized paraffin acid value: The oxidized paraffin acid values ​​of the examples and comparative examples were tested according to the industry standard "NB / SH / T 0809 Determination of Acid Value of Natural and Synthetic Waxes". The specific steps are as follows: Accurately weigh 1 g of paraffin oxide sample (accurate to 0.001 g) and place it in a 250 mL Erlenmeyer flask; add 40 mL of xylene to the Erlenmeyer flask and install a spherical reflux condenser; heat using a water bath or hot plate, shaking continuously, until the sample is completely dissolved in the solvent; add 3-5 drops of phenolphthalein indicator to the hot solution; while still hot, titrate with a standardized potassium hydroxide ethanol standard solution (usually about 0.1 mol / L), shaking the Erlenmeyer flask continuously, until the solution turns a light pink color and remains so for at least 10 seconds, which is the titration endpoint; record the volume of potassium hydroxide ethanol standard solution consumed; to prevent sample saponification, the titration process should be rapid and repeated heating should be avoided; perform a blank test (without sample) under the same conditions and record the volume of potassium hydroxide ethanol standard solution consumed in the blank titration; calculate the acid value based on the measured data, and the test results are shown in Table 2 below.

[0046] 2. Saponification value of oxidized paraffin: The saponification value of oxidized paraffin in the examples and comparative examples was determined according to GB / T 8021 "Determination of Saponification Value of Petroleum Products". The specific steps are as follows: Accurately weigh 3 g (accurate to 0.001 g) of the dehydrated and mechanically impurity-free paraffin wax sample and place it in a 250 mL Erlenmeyer flask. Use a pipette to accurately add 50 mL of 0.5 mol / L potassium hydroxide ethanol standard solution to the Erlenmeyer flask. Connect the Erlenmeyer flask to a reflux condenser and heat under reflux in a boiling water bath for at least 30 minutes until saponification is complete (this can be determined by checking if the solution is clear or free of oil droplets). After saponification, allow it to cool slightly and add 5-10 drops of phenolphthalein indicator; the solution should turn red. Titrate with 0.5 mol / L hydrochloric acid standard solution while hot until the red color of the solution just disappears, which is the endpoint. Record the volume of hydrochloric acid consumed. Perform a blank test under identical conditions, but without adding the paraffin wax sample. Record the volume of hydrochloric acid consumed in the blank test. Calculate the saponification value based on the measured data. The test results are shown in Table 2 below.

[0047] 3. Damp Heat Test: Damp heat tests were conducted on the rust-preventive waxes prepared in the examples and comparative examples. Referring to the damp heat test method for rust-preventive greases (GB / T 2361-1992), steel sheets were cleaned with petroleum ether, coated with rust-preventive wax, and placed at room temperature for 48 hours. The coated steel sheets were then placed in a damp heat test chamber with a relative humidity above 95% and a temperature of 49±1℃ for 240 hours. The corrosion status was then determined, and the results are shown in Table 2 below.

[0048] 4. Salt spray test: Salt spray tests were conducted on the rust-preventive waxes prepared in the examples and comparative examples. Referring to the petrochemical industry standard SH / T 0081-1991, the test pieces were first cleaned of oil stains with petroleum ether, then cleaned once with ethanol, and dried. The rust-preventive wax was then sprayed using an air compressor and spray gun at a pressure of 3 kg, resulting in a wax film mass of approximately 2 g. The edges and back were protected with transparent tape, and then placed in a salt spray test chamber under experimental conditions. The chamber was operated at a temperature of 35±1 ℃ for 240 h. The corrosion status was then determined, and the results are shown in Table 2 below.

[0049] Table 2 - Performance test results of paraffin oxide and rust-preventive wax in the embodiments and comparative examples of this application. As shown in Table 2, in Example 1 of this application, the oxidized paraffin wax, through the catalytic action provided by the catalyst loaded with active metals Mn and Ce, effectively improved the acid value and saponification value of the oxidized paraffin wax. Simultaneously, when applied as an anti-rust wax, it met the anti-rust requirements of damp heat and salt spray tests, demonstrating excellent anti-corrosion effects. In contrast, Comparative Example 9 did not add a catalyst, resulting in a decrease in both the acid value and saponification value of the prepared oxidized paraffin wax, reduced antioxidant capacity, and insufficient anti-corrosion performance of the anti-rust wax, leading to rusting phenomena in damp heat and salt spray tests.

[0050] Compared to Example 1, Example 2 only loaded Mn into the catalyst, resulting in a reduced catalytic effect. The acid value and saponification value of the prepared oxidized paraffin both decreased, indicating that simultaneous loading of Ce as an active component in the catalyst can improve the catalytic effect on oxidized paraffin, leading to higher catalytic oxidation activity and thus enhancing the antioxidant capacity of the oxidized paraffin. The catalysts in Comparative Examples 1-3, in addition to being loaded with Mn, also additionally loaded with copper and iron metal salts, respectively. Although the acid value and saponification value of the prepared oxidized paraffin were higher than in Example 2, their anti-corrosion function was insufficient when applied to rust-preventive waxes, resulting in rusting during salt spray testing. This demonstrates that when the catalyst is simultaneously loaded with Mn and Ce, it exhibits stronger resistance to hydrochloric acid and superior anti-corrosion effect compared to other active components.

[0051] Compared to Example 1, the catalysts in Comparative Examples 3-6 were only loaded with Co, Fe, Cu, and Ce elements, resulting in lower catalytic oxidation activity. The acid value and saponification value of the prepared oxidized paraffin were reduced, and the antioxidant capacity was poor. Moreover, after being applied as an anti-rust wax, rusting occurred in damp heat tests or smoke tests, indicating insufficient anti-corrosion performance.

[0052] Compared to Example 1, the ratio of Mn and Ce active components loaded in the catalysts of Examples 4-5 differs. Examples 4-5 show a tendency for decreased catalytic activity due to higher Mn or Ce loading ratios. By controlling the Mn and Ce ratio in the catalyst within the range of Example 1, not only can the acid value and saponification value of the prepared oxidized paraffin be improved, but the rust-preventive wax also exhibits excellent anti-corrosion effects in humid, hot, and acidic environments. In Comparative Example 7, the excessively high Mn loading in the catalyst led to rusting during the salt spray test of the applied rust-preventive wax. In Comparative Example 8, the excessively high Ce loading not only significantly reduced the acid value and saponification value of the oxidized paraffin but also affected the anti-corrosion effect of the rust-preventive wax in the salt spray test environment, resulting in rusting.

[0053] Compared to Example 1, the emulsifier used in Example 10 is sodium dodecyl sulfate, and the emulsifier used in Example 11 is fatty alcohol polyoxyethylene ether. These not only can uniformly disperse the components in the rust-preventive wax to ensure antioxidant balance, but also avoid interfering with the antioxidant effects of oxidized paraffin and rust-preventive wax. In contrast, the emulsifier used in the rust-preventive wax of Comparative Example 10 is oleic acid, which results in a significant deficiency in the anti-corrosion performance of the rust-preventive wax, making it prone to rusting in humid and hot environments as well as acidic and alkaline environments.

[0054] Compared to Example 1, the rust-preventive wax in Example 10 uses alkenyl succinic acid, and the rust-preventive wax in Example 11 uses α-mercaptobenzothiazole, which can work in combination with oxidized paraffin to improve the anti-corrosion effect and meet the rust prevention requirements of damp heat test and salt spray test. However, the rust-preventive wax in Comparative Example 11 uses barium petroleum sulfonate, and the rust-preventive wax in Comparative Example 12 uses benzotriazole, which cannot effectively synergize with oxidized paraffin, resulting in insufficient anti-corrosion performance and easy rusting in humid and acidic / alkaline environments.

[0055] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A method for preparing oxidized paraffin, characterized in that, Includes the following steps: (1) After dissolving the metal salt in water, a carrier is added, the mixture is mixed and allowed to stand for a period of time, then dried and subsequently calcined to obtain a catalyst; the metal element of the metal salt includes Mn; (2) After heating and stirring the paraffin to dissolve it, a catalyst is added and air is continuously introduced to carry out oxidation treatment. After cooling, oxidized paraffin is obtained.

2. The method for preparing oxidized paraffin as described in claim 1, characterized in that, In step (1), the metal salt also includes an auxiliary metal element, which is Co and / or Ce, and the mass ratio between the Mn-containing metal salt and the metal salt containing the auxiliary metal element is (1-3):

1.

3. The method for preparing oxidized paraffin as described in claim 2, characterized in that, The metal salt containing Mn is at least one of MnSO4, Mn(NO3)2, and MnCl2; And / or, the Co-containing metal salt is CoCl2 and / or Co(NO3)2; And / or, the metal salt containing Ce is Ce(NO3)3.

4. The method for preparing oxidized paraffin as described in claim 1, characterized in that, In step (1), all the metal elements of the metal salt account for 10%-30% of the carrier mass; And / or, the carrier is at least one of ZSM-5, SBA-15, MCM-41, Al2O3, and SiO2; And / or, in step (1), the mixing time is 1-3 h and the settling time is 6-10 h; And / or, in step (1), the drying temperature is 60-110 °C and the time is 7-12 h; And / or, in step (1), the calcination temperature is 300-500 ℃ and the time is 2-5 h.

5. The method for preparing oxidized paraffin as described in claim 1, characterized in that, In step (2), the catalyst accounts for 0.5%-2% of the mass fraction of paraffin; And / or, in step (2), the volumetric hourly space velocity of the introduced air is 0.5-1.2 h⁻¹. -1 ; And / or, in step (2), the oxidation treatment temperature is 120-190 °C and the time is 1-9 h.

6. An oxidized paraffin prepared by the method for preparing oxidized paraffin as described in any one of claims 1-5.

7. A rust-preventive wax, characterized in that, The method uses the oxidized paraffin as described in claim 6, comprising oxidized paraffin, emulsifier, rust inhibitor and water, wherein the emulsifier is at least one of sorbitan monooleate, sodium dodecyl sulfate and fatty alcohol polyoxyethylene ether; and the rust inhibitor is at least one of cyclohexylamine stearate, alkenyl succinic acid and α-mercaptobenzothiazole.

8. The rust-preventive wax as described in claim 7, characterized in that, The mass ratio of the oxidized paraffin to the emulsifier is 10:(4-9); And / or, the mass ratio of the oxidized paraffin to the rust inhibitor is 10:(5-15).

9. The rust-preventive wax as described in claim 7, characterized in that, The total amount of the oxidized paraffin, emulsifier, and rust inhibitor accounts for 20%-70% of the water mass fraction.

10. A method for preparing a rust-preventive wax as described in any one of claims 7-9, characterized in that, Includes the following steps: The oxidized paraffin, emulsifier, rust inhibitor and water are mixed and stirred at 60-150 ℃ for 10-80 min. After cooling, the rust-inhibiting wax is obtained.

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