Non-ionic polyether demulsifier as well as preparation method and application thereof

Abstract

The invention provides a nonionic polyether demulsifier as well as a preparation method and application thereof, and belongs to the technical field of demulsifiers. The non-ionic polyether demulsifier provided by the invention comprises the following components in parts by mass: 25-45 parts of a non-ionic surfactant, 0.1-5 parts of a dispersing agent, 35-55 parts of a cosolvent and 0.1-1 part of an antioxidant. By adding the nonionic surfactant, the dispersing agent and the cosolvent, oil-water interfacial tension can be reduced, oil-water separation can be promoted, demulsification time can be shortened, demulsification efficiency can be improved, excellent demulsification performance can be exerted under wider conditions, and adverse effects of emulsion on equipment can be reduced; original performance can be kept for a long time by adding the antioxidant, performance reduction caused by oxidation is prevented, inventory management and long-term use are facilitated, and effectiveness and reliability in practical application are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of demulsifiers, and in particular to a nonionic polyether demulsifier and a preparation method and application thereof. Background Art

[0002] Lubricating oil plays a vital role in industrial production. It can not only reduce friction loss between mechanical equipment, improve equipment efficiency, but also extend equipment service life. However, in actual application, due to the influence of the external environment and the shear force caused by the mechanical operation of the equipment, lubricating oil often mixes with water to form an emulsion, which reduces lubrication performance and increases the risk of wear, and may cause corrosion and other problems, thereby affecting the normal operation of the equipment and reducing its service life. Therefore, effectively solving the emulsification problem in lubricating oil is the key to maintaining the stable operation of equipment.

[0003] Adding demulsifiers is considered a simple and effective means to enhance the demulsification ability of lubricating oils. Among them, non-ionic polyether demulsifiers have shown excellent performance in breaking oil-water emulsions due to their good water solubility and surface activity. This type of demulsifier achieves demulsification by reducing the oil-water interfacial tension, changing the charge state of the emulsified particles, and promoting oil-water separation. In addition, non-ionic polyether demulsifiers are not easily affected by changes in water hardness and pH value, and can maintain stable demulsification ability under a variety of working conditions. They are widely used in oil extraction, refining and processing and other fields.

[0004] Existing nonionic polyether demulsifiers have the problem of long demulsification time. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a nonionic polyether demulsifier and a preparation method and application thereof. The nonionic polyether demulsifier of the present invention has a short demulsification time and a good demulsification effect.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The invention provides a nonionic polyether demulsifier, comprising the following components in parts by weight: 25-45 parts of a nonionic surfactant, 0.1-5 parts of a dispersant, 35-55 parts of a cosolvent and 0.1-1 parts of an antioxidant.

[0008] Preferably, the mass fraction of the nonionic surfactant in the nonionic polyether demulsifier is 30 to 40 parts.

[0009] Preferably, the nonionic surfactant includes one or more of polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitan monofatty acid esters, polyoxyethylene-polyoxypropylene block copolymers, polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymers, ethylene oxide-propylene oxide block copolymers and polyether-modified siloxane block copolymers.

[0010] Preferably, the mass fraction of the dispersant in the nonionic polyether demulsifier is 0.2 to 3 parts.

[0011] Preferably, the dispersant comprises one or more of polyisobutylene succinic anhydride, polyether amine, phosphate ester and polyethylene imine.

[0012] Preferably, the mass fraction of the co-solvent in the non-ionic polyether demulsifier is 40 to 50 parts.

[0013] Preferably, the co-solvent comprises one or more of ethyl acetate, glycol ether, toluene, xylene, propylene glycol and ethylene oxide-propylene oxide mixture.

[0014] Preferably, the weight fraction of the antioxidant in the nonionic polyether demulsifier is 0.3 to 0.5 parts.

[0015] The present invention also provides a method for preparing the nonionic polyether demulsifier described in the above technical solution, comprising the following steps:

[0016] The nonionic surfactant, dispersant, cosolvent and antioxidant are mixed to obtain the nonionic polyether demulsifier.

[0017] The present invention also provides the use of the nonionic polyether demulsifier described in the above technical solution in the field of lubrication.

[0018] The invention provides a nonionic polyether demulsifier, comprising the following components in parts by weight: 25-45 parts of a nonionic surfactant, 0.1-5 parts of a dispersant, 35-55 parts of a cosolvent and 0.1-1 parts of an antioxidant.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The addition of nonionic surfactants, dispersants and cosolvents in the present invention can help reduce the oil-water interfacial tension, promote oil-water separation, show significant advantages in demulsification time, fast demulsification speed, shorten the demulsification time, improve demulsification efficiency, and can play the excellent demulsification performance of the present invention under a wider range of conditions, reducing the adverse effects of the emulsion on the equipment; the addition of antioxidants can maintain its original performance for a long time, prevent the performance degradation caused by oxidation, and is conducive to inventory management and long-term use, ensuring its effectiveness and reliability in practical applications; at the same time, the nonionic polyether demulsifier of the present invention can change the properties of the emulsified membrane by specifically limiting the composition of the raw materials, making it more fragile, and the rupture of the emulsified membrane will cause the separation of oil droplets and water droplets, thereby achieving effective demulsification. By destroying the emulsified membrane, the demulsifier can prevent the oil droplets from being redispersed in the water, and can clearly separate the oil and water, ensuring that the separated oil is pure and reusable. The present invention improves the lubricating performance of the lubricating oil by optimizing the composition and ratio of the demulsifier, reduces the friction damage of the fasteners, and extends the service life of the parts.

[0021] Furthermore, the components of the present invention can be decomposed into harmless substances such as water and carbon dioxide by microorganisms in the natural environment, reducing their accumulation in the environment and reducing the risk of long-term impact on the ecosystem; each component has a high solubility in water and does not contain heavy metals or other harmful substances, so it has low toxicity to aquatic organisms and soil microorganisms; it is relatively safe during use and has a low health risk to operators, which meets the current high requirements for sustainable development and environmental protection.

[0022] The present invention also provides a method for preparing the nonionic polyether demulsifier described in the above technical solution. The nonionic polyether demulsifier of the present invention has mild production conditions and significant demulsification effect, and can maintain excellent demulsification performance even after multiple uses. DETAILED DESCRIPTION

[0023] The invention provides a nonionic polyether demulsifier, comprising the following components in parts by weight: 25-45 parts of a nonionic surfactant, 0.1-5 parts of a dispersant, 35-55 parts of a cosolvent and 0.1-1 parts of an antioxidant.

[0024] In the present invention, unless otherwise specified, the raw materials used are all commercially available products in the art.

[0025] In the present invention, the mass fraction of the nonionic surfactant in the nonionic polyether demulsifier is preferably 30 to 40 parts, specifically 25, 30, 35, 40 or 45 parts.

[0026] In the present invention, the nonionic surfactant preferably includes one or more of polyoxyethylene sorbitan fatty acid ester, polyoxyethylene anhydrous sorbitan monofatty acid ester, polyoxyethylene-polyoxypropylene block copolymer, polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, ethylene oxide-propylene oxide block copolymer and polyether modified siloxane block copolymer, and more preferably ethylene oxide-propylene oxide block copolymer; the nonionic surfactant can significantly reduce the tension of the oil-water interface, so that the oil droplets are more easily merged and settled. In the demulsification process, the nonionic surfactant can be adsorbed on the surface of the emulsified particles, affecting the re-aggregation between the particles, preventing the oil and water from being emulsified again, that is, preventing the separated oil droplets from being redispersed in the water to form a new emulsion, ensuring the continuity and stability of the demulsification effect. The nonionic surfactant usually has good stability to pH and temperature changes, so it can maintain its demulsification performance under different conditions and is suitable for a variety of working conditions.

[0027] In a specific embodiment of the present invention, the ethylene oxide-propylene oxide block copolymer is preferably poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol), which is purchased from Aladdin with a product model of F-68 (average Mn ~ 8,400 (EO:PO = 4:1)).

[0028] Based on the mass fraction of the nonionic surfactant, the mass fraction of the dispersant in the nonionic polyether demulsifier is preferably 0.2 to 3 parts, specifically 0.1, 0.2, 1, 3 or 5 parts.

[0029] In the present invention, the dispersant preferably includes one or more of polyisobutylene succinic anhydride, polyether amine, phosphate ester and polyethylene imine; the dispersant can combine with pollutants (including dust, metal dust and oil stains) in the lubricating oil to form easily separable compounds, prevent their deposition, and improve the cleanliness of the lubricating oil.

[0030] Based on the mass fraction of the nonionic surfactant, the mass fraction of the cosolvent in the nonionic polyether demulsifier is preferably 40 to 50 parts, specifically 35, 40, 45, 50 or 55 parts.

[0031] In the present invention, the co-solvent preferably includes one or more of ethyl acetate, ethylene glycol ether, toluene, xylene, propylene glycol and ethylene oxide-propylene oxide mixture, more preferably a mixture of toluene and xylene, and the mass ratio of toluene and xylene in the mixture of toluene and xylene is preferably 20:25; the role of the co-solvent is to improve the solubility of the demulsifier, increase the solubility of the water phase in the oil-water mixture, help the demulsifier to be better dispersed in the oil phase, and promote the aggregation of oil droplets and oil-water separation.

[0032] In the present invention, the mass ratio of ethylene oxide to propylene oxide in the ethylene oxide-propylene oxide mixture is preferably 1-3:1-3, specifically 1:1, 2:1, 1:2, 3:1 and 1:3.

[0033] Based on the mass fraction of the nonionic surfactant, the mass fraction of the antioxidant in the nonionic polyether demulsifier is preferably 0.3 to 0.5 parts, specifically 0.1, 0.3, 0.5 or 1 part.

[0034] In the present invention, the antioxidant preferably includes one or more of 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butylphenol, N,N'-di-sec-butyl-p-phenylenediamine and dilauryl thiodipropionate; the antioxidant can interrupt the oxidation chain reaction in the demulsifier, decompose peroxides, protect the demulsifier from oxidation during storage, and maintain its stable performance.

[0035] The present invention also provides a method for preparing the nonionic polyether demulsifier described in the above technical solution, comprising the following steps:

[0036] The nonionic surfactant, dispersant, cosolvent and antioxidant are mixed to obtain the nonionic polyether demulsifier.

[0037] The present invention has no particular limitation on the specific manner of mixing, and any manner familiar to those skilled in the art may be used.

[0038] In a specific embodiment of the present invention, the nonionic surfactant and the dispersant are first mixed to obtain a first mixture; the first mixture is second mixed with a co-solvent and an antioxidant to obtain a second mixture; the second mixture is continuously stirred for 1 hour to obtain the nonionic polyether demulsifier.

[0039] In the present invention, the first mixing is preferably performed under stirring conditions. The present invention has no particular limitation on the time and speed of the stirring, and a method well known to those skilled in the art can be used to mix uniformly.

[0040] After obtaining the first mixture, the present invention performs a second mixing of the first mixture with a co-solvent and an antioxidant to obtain a second mixture.

[0041] In the present invention, the second mixing is preferably carried out under stirring conditions. The present invention has no particular limitation on the stirring time and speed, and a method well known to those skilled in the art can be used to mix uniformly.

[0042] After obtaining the second mixture, the second mixture is continuously stirred for 1 hour to obtain the nonionic polyether demulsifier. The present invention has no particular limitation on the stirring time and speed, and the mixture can be uniformly mixed using a method known to those skilled in the art.

[0043] The present invention also provides the use of the nonionic polyether demulsifier described in the above technical solution in the field of lubrication.

[0044] The present invention has no particular limitation on the specific manner of the application, and any manner familiar to those skilled in the art may be used.

[0045] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] Raw materials used in the examples:

[0047] Ethylene oxide-propylene oxide block copolymer was purchased from Aladdin, the product model is F-68 (average Mn ~ 8,400 (EO:PO = 4:1)).

[0048] Example 1

[0049] Prepare nonionic polyether demulsifier according to the mass fraction of each component:

[0050] Weigh 40 parts of ethylene oxide-propylene oxide block copolymer, 45 parts of toluene, 0.2 parts of phosphate ester, and 0.5 parts of N,N'-di-sec-butyl-p-phenylenediamine.

[0051] Add polyoxyethylene-polyoxypropylene block copolymer and phosphate ester into a container, stir until the components are evenly mixed, stirring at a rate of 400 r / min; add toluene and N,N'-di-sec-butyl-p-phenylenediamine, continue to stir the mixture, stirring at a rate of 400 r / min, after sufficient mixing, continue stirring for 1 hour to obtain a non-ionic polyether demulsifier.

[0052] Example 2

[0053] Prepare nonionic polyether demulsifier according to the mass fraction of each component:

[0054] Weigh 40 parts of ethylene oxide-propylene oxide block copolymer, 45 parts of xylene, 0.2 parts of phosphate ester, and 0.5 parts of N,N'-di-sec-butyl-p-phenylenediamine.

[0055] The preparation process is the same as that in Example 1.

[0056] Example 3

[0057] Prepare nonionic polyether demulsifier according to the mass fraction of each component:

[0058] Weigh 40 parts of ethylene oxide-propylene oxide block copolymer, 20 parts of toluene, 25 parts of xylene, 0.2 parts of phosphate ester, and 0.5 parts of N,N'-di-sec-butyl-p-phenylenediamine.

[0059] The preparation process is the same as that in Example 1.

[0060] Example 4

[0061] Prepare nonionic polyether demulsifier according to the mass fraction of each component:

[0062] Weigh 25 parts of ethylene oxide-propylene oxide block copolymer, 35 parts of toluene, 1 part of phosphate ester, and 1 part of N,N'-di-sec-butyl-p-phenylenediamine.

[0063] The preparation process is the same as that in Example 1.

[0064] Example 5

[0065] Prepare nonionic polyether demulsifier according to the mass fraction of each component:

[0066] Weigh 25 parts of ethylene oxide-propylene oxide block copolymer, 35 parts of xylene, 3 parts of phosphate ester, and 1 part of N,N'-di-sec-butyl-p-phenylenediamine.

[0067] The preparation process is the same as that in Example 1.

[0068] Performance Testing Methods

[0069] Demulsification performance Two groups of experiments were designed based on the national standard GB_T 7605-2008. The first group of experiments was tested according to the national standard GB_T 7605-2008, and the demulsification performance of the samples was tested three times in a row; the second group was based on the national standard GB_T7605-2008, and the oil-water ratio (volume ratio) was changed from 1:1 to 3:1, 5:1 and 7:1 to test the demulsification performance of the demulsifier under different oil-water ratio conditions. Demulsifiers P1 and P2 were selected for comparative experiments with demulsifiers prepared from Examples 1 to 5 of the present invention. Among them, P1, P2 and base oil were commercially available. The experiment selected 150N base oil with a kinematic viscosity of 150cSt, and the addition amount of each demulsifier was 0.3% of the mass of the base oil. The demulsification performance was studied using the above two groups of demulsification experiments, and the results are shown in Tables 1 and 2.

[0070] The results are analyzed as follows:

[0071] 1. From Table 1, it can be seen that in terms of demulsification time, when no component is added to the base oil, the demulsification time is 15 to 20 minutes. After adding the demulsifiers of Examples 1 to 5, the demulsification time is reduced to 7 to 14 minutes. The demulsification time is significantly reduced, indicating that a better demulsification effect is achieved.

[0072] After the commercially available demulsifiers P1 and P2 were added, the demulsification time of the stirring method was 13-19 min and 15-22 min, respectively. The demulsification time did not change significantly, and even increased compared with the demulsification time of the base oil, indicating that the demulsification effect was general. Among them, the demulsification time of Example 3 was shorter than that of Examples 1 and 2, indicating that the demulsifier prepared from the xylene-toluene mixture was better than the demulsifier prepared from single toluene (xylene).

[0073] In addition, the demulsification time of Examples 1 to 5 was reduced after continuous experiments, and the demulsification effect of the sample with commercially available demulsifier P1 was significantly weakened after continuous experiments, indicating that Examples 1 to 3 have good continuous demulsification capabilities.

[0074] 2. From Table 2, it can be seen that in terms of demulsification time of water and oil at different ratios, when no component is added to the base oil, the demulsification time is 16-20 minutes. After adding the demulsifiers of Examples 1-5, the demulsification time is 10-13 minutes, and the demulsification time is significantly reduced, indicating that a good demulsification effect is achieved; and after adding the commercially available demulsifiers P1 and P2, the demulsification time is 13-16 minutes and 15-20 minutes, respectively. This further proves that Examples 1-3 are more excellent in shortening the demulsification time and can show better demulsification effects in different oil-water environments.

[0075] Table 1 Continuous demulsification test results

[0076]

[0077] Table 2 Demulsification test results at different oil-water ratios

[0078]

[0079]

[0080] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A nonionic polyether demulsifier, characterized in that: The invention comprises the following components in parts by weight: 25 to 45 parts of a nonionic surfactant, 0.1 to 5 parts of a dispersant, 35 to 55 parts of a cosolvent and 0.1 to 1 part of an antioxidant.

2. The nonionic polyether demulsifier according to claim 1, characterized in that: The mass fraction of the nonionic surfactant in the nonionic polyether demulsifier is 30 to 40 parts.

3. The nonionic polyether demulsifier according to claim 1 or 2, characterized in that: The nonionic surfactant includes one or more of polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitan monofatty acid ester, polyoxyethylene-polyoxypropylene block copolymer, polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, ethylene oxide-propylene oxide block copolymer and polyether modified siloxane block copolymer.

4. The nonionic polyether demulsifier according to claim 1, characterized in that: The mass fraction of the dispersant in the nonionic polyether demulsifier is 0.2 to 3 parts.

5. The nonionic polyether demulsifier according to claim 1 or 4, characterized in that: The dispersant includes one or more of polyisobutylene succinic anhydride, polyether amine, phosphate ester and polyethylene imine.

6. The nonionic polyether demulsifier according to claim 1, characterized in that: The mass fraction of the co-solvent in the non-ionic polyether demulsifier is 40 to 50 parts.

7. The nonionic polyether demulsifier according to claim 1 or 6, characterized in that: The co-solvent includes one or more of ethyl acetate, glycol ether, toluene, xylene, propylene glycol and ethylene oxide-propylene oxide mixture.

8. The nonionic polyether demulsifier according to claim 1, characterized in that: The weight percentage of the antioxidant in the nonionic polyether demulsifier is 0.3 to 0.5 parts.

9. The method for preparing the nonionic polyether demulsifier according to any one of claims 1 to 8, characterized in that: The following steps are involved: The nonionic surfactant, dispersant, cosolvent and antioxidant are mixed to obtain the nonionic polyether demulsifier.

10. Use of the nonionic polyether demulsifier according to any one of claims 1 to 8 in the field of lubrication.

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