Emulsion type defoaming agent and preparation method thereof

Abstract

The invention belongs to the technical field of defoaming agents, and discloses an emulsion type defoaming agent and a preparation method thereof. The emulsion type defoaming agent comprises 15-32 parts of a defoaming active substance, 3-12 parts of an emulsifier and 60-75 parts of a dispersion medium, the defoaming active substance comprises higher fatty alcohol, polyether and mineral oil; the emulsifier comprises stearic acid polyether ester and stearic acid, and the mass ratio of the stearic acid polyether ester to the stearic acid is (6-8): (2-4). The emulsion type defoaming agent provided by the invention has excellent defoaming and foam inhibition effects and strong stability; under the condition of not containing an organic silicon defoaming agent, the defoaming agent can simultaneously meet the requirements of rapid defoaming, foam inhibition, degassing and stable storage, and can be used as a papermaking defoaming agent with excellent performance.

Description

Technical Field

[0001] The invention belongs to the technical field of defoamers, and particularly relates to an emulsion defoamer and a preparation method thereof. Background Art

[0002] In the industrial production process, as long as the process involves stirring, there will be foam problems, such as papermaking industry, textile printing and dyeing, paint processing, sewage treatment, biological fermentation, etc. Therefore, a large number of chemical additives are needed to meet different purposes, so defoaming agents came into being.

[0003] In the papermaking process, due to turbulence and water absorption, air enters the water to form tiny bubbles, or foam accumulates in the front box of the fourdrinier paper machine. Sometimes, as the pulp goes online, defects such as color spots and holes are produced on the paper surface, which reduces the quality of the paper and affects the dehydration rate of papermaking. In the production of paperboard, a large amount of foam often accumulates in the regulating box, sand settling tray, pulp screen and round screen slot, causing the water level of the round screen to fluctuate and the sizing to be uneven, thus causing the fluctuation of the full-width quantitative, resulting in defects such as blistering and stratification, which seriously affects the normal production and product quality.

[0004] The air content in pulp is mainly related to the characteristics of the fiber surface. The resin content in pulp affects the hydrophobicity of cellulose. The higher the resin content, the more air bubbles there are. In addition, the potential of the fiber surface also has a great influence on the attachment of microbubbles. If a cationic surfactant is added to the pulp, the electronegativity of the fiber surface will be reduced or changed, so that negatively charged microbubbles will be attached to the fiber surface. In order to remove bubbles, surfactants are added as defoamers during the papermaking process to promote the bubbles mixed in the liquid to merge into larger bubbles, thereby accelerating the rise of bubbles, and they disappear quickly when they reach the liquid surface.

[0005] At present, the best defoaming effect is the organic silicon defoamer, which is to use an emulsifier to mix dimethyl silicone oil with SiO 2 The composite is emulsified to prepare a water emulsion product, but it is unstable and will cause SiO 2 Decomposition leads to decreased defoaming and antifoaming effects, and easy demulsification and instability. Some defoamers are mainly composed of fatty alcohols and their derivatives. Their advantages are that they can quickly and efficiently remove gases from slurries and eliminate foam on the water surface, and their use costs are low. For example, patent CN1538866A discloses a new type of deaerator, which contains oxygenated organic matter and an amide compound to improve the defoaming effect; patent CN1787574A discloses the preparation of a water-in-oil emulsion defoamer composition, which includes an adduct of fatty alcohols, C2-C4 unsaturated oxides and primary alcohols with branched alkyl groups. However, these are all complicated production processes, and some raw materials are difficult to obtain, resulting in certain difficulties in production implementation.

[0006] Therefore, there is an urgent need to provide a defoaming agent with excellent defoaming and anti-foaming effects, strong stability, readily available raw materials, and simple preparation process. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention provides an emulsion defoamer and a preparation method thereof. The emulsion defoamer provided by the present invention has excellent defoaming and antifoaming effects, strong stability, and easy-to-obtain raw materials and a simple preparation process.

[0008] The invention provides an emulsion defoamer.

[0009] Specifically, an emulsion defoamer comprises the following components by weight:

[0010] 15-32 parts of defoaming active substance, 3-12 parts of emulsifier and 60-75 parts of dispersion medium; the defoaming active substance includes higher fatty alcohol, polyether and mineral oil; the emulsifier includes stearic acid polyether ester and stearic acid, and the mass ratio of the stearic acid polyether ester to the stearic acid is (6-8): (2-4).

[0011] Preferably, the emulsion defoamer comprises the following components, by weight: 18-30 parts of defoaming active substances, 3-12 parts of emulsifiers, and 65-75 parts of dispersion medium; further preferably, the emulsion defoamer comprises the following components, by weight: 20-28 parts of defoaming active substances, 4-10 parts of emulsifiers, and 65-72 parts of dispersion medium.

[0012] Preferably, the mass ratio of the stearic acid polyether ester to the stearic acid is (6-7.5):(2.5-4).

[0013] Preferably, the dispersion medium is water, such as ultrapure water.

[0014] Preferably, in the defoaming active substance, the mass ratio of the higher fatty alcohol, the polyether and the mineral oil is (1.0-2.5):(2.0-4.0):1; further preferably, the mass ratio of the higher fatty alcohol, the polyether and the mineral oil is (1.0-2.0):(2.0-3.5):1.

[0015] Preferably, the higher fatty alcohol includes at least one of cetyl alcohol, stearyl alcohol, arachidyl alcohol and behenyl alcohol.

[0016] Preferably, the general structural formula of the polyether is: R 1 (EO) m (PO) n H, where R 1It is a long alkyl chain of C16-C22, m is 5-12, and n is 20-60.

[0017] Preferably, the mineral oil is selected from at least one of 11# white oil, 15# white oil and 18# white oil.

[0018] Preferably, the emulsion defoamer further comprises 0.01-0.1 parts of a bactericide by weight. The bactericide is preferably chloramine.

[0019] The invention also provides a method for preparing the emulsion defoamer.

[0020] Specifically, the preparation method of the emulsion defoamer comprises the following steps:

[0021] The defoaming active substance, emulsifier and dispersing medium are heated, mixed and homogenized to prepare an emulsion type defoaming agent.

[0022] More specifically, the preparation method of the emulsion defoamer comprises the following steps:

[0023] The defoaming active substance and the emulsifier are mixed, heated to 60-80°C, and stirred for 5-20 minutes; then a dispersion medium at 60-80°C is added and homogenized to obtain an emulsion defoaming agent.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The emulsion defoamer provided by the present invention comprises a defoaming active substance, an emulsifier and a dispersion medium. The present invention optimizes the components and the amounts of the components, uses a compound stearic acid polyether ester as an emulsifier, and controls the mass ratio of stearic acid polyether ester to stearic acid to be (6-8): (2-4), thereby being able to prepare an emulsion defoamer with excellent defoaming and anti-foaming effects and strong stability.

[0026] (2) The emulsion defoamer provided by the present invention can simultaneously meet the requirements of rapid defoaming, foam suppression, degassing, and stable storage without containing an organosilicon defoamer, and can be used as a papermaking defoamer with excellent performance.

[0027] (3) The emulsion defoamer provided by the present invention has readily available raw materials and a simple preparation process, and has the advantages of safety and stability during production. DETAILED DESCRIPTION

[0028] In order to make the technical scheme of the present invention more clearly understood by those skilled in the art, the following embodiments are listed for illustration. It should be pointed out that the following embodiments do not limit the protection scope of the present invention.

[0029] Unless otherwise specified, the raw materials, reagents or devices used in the following examples and comparative examples can be obtained from conventional commercial sources or by existing known methods.

[0030] Example 1

[0031] This embodiment provides an emulsion defoamer for papermaking and papermaking, which comprises the following components by weight: 2 parts of hexadecanol, 5 parts of octadecyl alcohol, 11 parts of higher fatty alcohol polyether C 16 H 33 O(EO) 5 (PO) 20 H, 1 part of 11# white oil, 3 parts of 15# white oil, 8 parts of compound stearic acid polyether ester (the mass ratio of stearic acid polyether ester SG-9 to stearic acid is 6:4), 0.02 parts of bactericide (chloramine) and 69.98 parts of ultrapure water.

[0032] This embodiment also provides a method for preparing the emulsion defoamer, comprising the following steps:

[0033] According to the above weight parts, weigh cetyl alcohol, stearyl alcohol, and higher fatty alcohol polyether C 16 H 33 O(EO) 5 (PO) 20 H, 11# white oil, 15# white oil, compound stearic acid polyether ester and fungicide, heat the system to 60°C, stir for 5 minutes, then add 60°C ultrapure water, homogenize at 4000rpm for 20 minutes through a high shear emulsifier, cool to room temperature, and obtain emulsion defoamer S1.

[0034] Example 2

[0035] This embodiment provides an emulsion defoamer for papermaking and papermaking, which comprises the following components by weight: 6 parts of hexadecanol, 12 parts of higher fatty alcohol polyether C 16 H 33 O(EO) 5 (PO) 27 H, 5 parts of 11# white oil, 7 parts of compound stearic acid polyether ester (the mass ratio of stearic acid polyether ester SG-9 to stearic acid is 6.5:3.5), 0.05 parts of bactericide (chloramine) and 69.95 parts of ultrapure water.

[0036] This embodiment also provides a method for preparing the emulsion defoamer, comprising the following steps:

[0037] According to the above weight parts, weigh cetyl alcohol, higher fatty alcohol polyether C 16 H 33 O(EO) 5 (PO) 27H, 11# white oil, compound stearic acid polyether ester and fungicide, heat the system to 65°C, stir for 8 minutes, then add 65°C ultrapure water, homogenize at 4000rpm for 25 minutes through a high shear emulsifier, cool to room temperature, and obtain emulsion defoamer S2.

[0038] Example 3

[0039] This embodiment provides an emulsion defoamer for papermaking and papermaking, which comprises the following components by weight: 6 parts of octadecyl alcohol, 13 parts of higher fatty alcohol polyether C 18 H 37 O(EO) 8 (PO) 25 H, 3 parts of 15# white oil, 2 parts of 18# white oil, 6 parts of compound stearic acid polyether ester (the mass ratio of stearic acid polyether ester SG-9 to stearic acid is 7:3), 0.08 parts of bactericide (chloramine) and 69.92 parts of ultrapure water.

[0040] This embodiment also provides a method for preparing the emulsion defoamer, comprising the following steps:

[0041] According to the above weight parts, weigh octadecyl alcohol, higher fatty alcohol polyether C 18 H 37 O(EO) 8 (PO) 25 H, 18# white oil, 15# white oil, compound stearic acid polyether ester and fungicide, heat the system to 70°C, stir for 10 minutes, then add 70°C ultrapure water, homogenize at 4000rpm for 30 minutes through a high shear emulsifier, cool to room temperature, and obtain emulsion defoamer S3.

[0042] Example 4

[0043] This embodiment provides an emulsion defoamer for papermaking and papermaking, which comprises the following components by weight: 8 parts of eicosanol, 13 parts of higher fatty alcohol polyether C 20 H 41 O(EO) 9 (PO) 27 H, 2 parts of 11# white oil, 2 parts of 18# white oil, 5 parts of compound stearic acid polyether ester (the mass ratio of stearic acid polyether ester SG-9 to stearic acid is 7.2:2.8), 0.01 parts of bactericide (chloramine) and 69.99 parts of ultrapure water.

[0044] This embodiment also provides a method for preparing the emulsion defoamer, comprising the following steps:

[0045] According to the above weight parts, weigh eicosanol, higher fatty alcohol polyether C 20 H 41 O(EO)9 (PO) 27 H, 11# white oil, 18# white oil, compound stearic acid polyether ester and fungicide, heat the system to 75°C, stir for 13 minutes, then add 75°C ultrapure water, homogenize at 4000rpm for 35 minutes through a high shear emulsifier, cool to room temperature, and prepare emulsion defoamer S4.

[0046] Example 5

[0047] This embodiment provides an emulsion defoamer for papermaking, which comprises the following components by weight: 3 parts of octadecyl alcohol, 3 parts of behenyl alcohol, 14 parts of higher fatty alcohol polyether C 22 H 45 O(EO) 7 (PO) 29 H, 6 parts of 18# white oil, 4 parts of compound stearic acid polyether ester (the mass ratio of stearic acid polyether ester SG-9 to stearic acid is 7.5:2.5), 0.02 parts of bactericide (chloramine) and 69.98 parts of ultrapure water.

[0048] This embodiment also provides a method for preparing the emulsion defoamer, comprising the following steps:

[0049] According to the above weight parts, weigh octadecyl alcohol, behenyl alcohol, and higher fatty alcohol polyether C. 22 H 45 O(EO) 7 (PO) 29 H, 18# white oil, compound stearic acid polyether ester and fungicide, heat the system to 70°C, stir for 15 minutes, then add 70°C ultrapure water, homogenize at 4000rpm for 30 minutes through a high shear emulsifier, cool to room temperature, and obtain emulsion defoamer S5.

[0050] Comparative Example 1

[0051] This comparative example provides an emulsion defoamer for papermaking and papermaking, which comprises the following components by weight: 2 parts of hexadecanol, 5 parts of octadecyl alcohol, 11 parts of higher fatty alcohol polyether C 16 H 33 O(EO) 5 (PO) 20 H, 1 part of 11# white oil, 3 parts of 15# white oil, 8 parts of compound stearic acid polyether ester (the mass ratio of stearic acid polyether ester SG-9 to stearic acid is 5:5), 0.02 parts of bactericide (chloramine) and 69.98 parts of ultrapure water.

[0052] This comparative example also provides a method for preparing the emulsion defoamer, comprising the following steps:

[0053] According to the above weight parts, weigh cetyl alcohol, stearyl alcohol, and higher fatty alcohol polyether C 16 H 33 O(EO) 5 (PO) 20 H, 11# white oil, 15# white oil, compound stearic acid polyether ester and fungicide, heat the system to 60°C, stir for 5 minutes, then add 60°C ultrapure water, homogenize at 4000rpm for 20 minutes through a high shear emulsifier, cool to room temperature, and obtain emulsion defoamer R1.

[0054] Comparative Example 2

[0055] This comparative example provides an emulsion defoamer for papermaking and papermaking, which comprises the following components by weight: 2 parts of hexadecanol, 5 parts of octadecyl alcohol, 11 parts of higher fatty alcohol polyether C 16 H 33 O(EO) 5 (PO) 20 H, 1 part of 11# white oil, 3 parts of 15# white oil, 8 parts of compound stearic acid polyether ester (the mass ratio of stearic acid polyether ester SG-9 to stearic acid is 9:1), 0.02 parts of bactericide (chloramine) and 69.98 parts of ultrapure water.

[0056] This comparative example also provides a method for preparing the emulsion defoamer, comprising the following steps:

[0057] According to the above weight parts, weigh cetyl alcohol, stearyl alcohol, and higher fatty alcohol polyether C 16 H 33 O(EO) 5 (PO) 20 H, 11# white oil, 15# white oil, compound stearic acid polyether ester and fungicide, heat the system to 60°C, stir for 5 minutes, then add 60°C ultrapure water, homogenize at 4000rpm for 20 minutes through a high shear emulsifier, cool to room temperature, and obtain emulsion defoamer R2.

[0058] Comparative Example 3

[0059] This comparative example provides an emulsion defoamer for papermaking and papermaking, which comprises the following components by weight: 8 parts of eicosanol, 13 parts of higher fatty alcohol polyether C 20 H 41 O(EO) 9 (PO) 27 H, 2 parts of 11# white oil, 2 parts of 18# white oil, 5 parts of emulsifier OEO-105 (Jiangsu Hai'an), 0.01 parts of bactericide (chloramine) and 69.99 parts of ultrapure water.

[0060] This comparative example also provides a method for preparing the emulsion defoamer, comprising the following steps:

[0061] According to the above weight parts, weigh eicosanol, higher fatty alcohol polyether C 20 H 41 O(EO) 9 (PO) 27 H, 11# white oil, 18# white oil, emulsifier OEO-105, heat the system to 75°C, stir for 13 minutes, then add 75°C ultrapure water, homogenize at 4000rpm for 35 minutes through a high shear emulsifier, cool to room temperature, and obtain emulsion defoamer R3.

[0062] Product effect testing

[0063] The defoaming and antifoaming properties of the emulsion defoamers provided in Examples 1-5 and Comparative Examples 1-3 were tested, simulating the papermaking coating process and the papermaking white water environment, respectively, to test the defoaming and antifoaming properties of the embodiments, comparative examples and external sample M (commercially available defoamer for papermaking).

[0064] (1) Foam suppression performance test

[0065] Preparation of foaming liquid: Measure 5g of nonylphenol polyoxyethylene ether NP-10 and 2.5g of sodium dodecylbenzene sulfonate and dissolve them in 992.5mL of water. Mix and stir until a uniform transparent liquid is obtained.

[0066] Test method: Set the air flow rate of the foam analyzer to 8L / min, add 200mL of foaming liquid to a 500mL glass container with a scale, then add 0.01g of the defoaming agent of the embodiment and the comparative example respectively, set the temperature to 30°C, turn on the air pump and start timing, and record the corresponding time for the foam to reach a certain volume. The longer the time required for the foam to reach the same volume, the better the anti-foaming performance of the defoaming agent. The test results are shown in Table 1:

[0067] Table 1 Comparative test results of defoaming and defoaming performance of defoamers

[0068]

[0069] (2) Stability test of defoamer

[0070] 100 mL of the prepared defoamer was taken into a stoppered measuring cylinder, and the stability of the emulsion was observed at 1 h, 3 h, 6 h, 12 h, and 24 h. The test results are shown in Table 2.

[0071] Table 2

[0072]

[0073]

[0074] It can be seen from the test results in Table 1 and Table 2 that the defoaming and antifoaming performance and stability of the defoaming agent prepared in the embodiment of the present invention are better than those of the comparative example and the commercially available product M.

[0075] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An emulsion defoamer, characterized in that: By weight, it includes the following components: 15-32 parts of defoaming active substance, 3-12 parts of emulsifier and 60-75 parts of dispersion medium; the defoaming active substance includes higher fatty alcohol, polyether and mineral oil; the emulsifier includes stearic acid polyether ester and stearic acid, and the mass ratio of the stearic acid polyether ester to the stearic acid is (6-8): (2-4).

2. The emulsion defoamer according to claim 1, characterized in that The mass ratio of the stearic acid polyether ester to the stearic acid is (6-7.5):(2.5-4).

3. The emulsion defoamer according to claim 1 or 2, characterized in that The composition comprises the following components by weight: 18-30 parts of defoaming active substances, 3-12 parts of emulsifiers, and 65-75 parts of dispersion media.

4. The emulsion defoamer according to claim 1 or 2, characterized in that: The dispersion medium is water.

5. The emulsion defoamer according to claim 3, characterized in that In the defoaming active substance, the mass ratio of the higher fatty alcohol, the polyether and the mineral oil is (1.0-2.5):(2.0-4.0):

1.

6. The emulsion defoamer according to claim 5, characterized in that The higher fatty alcohol includes at least one of cetyl alcohol, stearyl alcohol, arachidyl alcohol and behenyl alcohol.

7. The emulsion defoamer according to claim 5, characterized in that The general structural formula of the polyether is: R1(EO) m (PO) n H, wherein R1 is a long alkyl chain of C16-C22, m is 5-12, and n is 20-60.

8. The emulsion defoamer according to claim 5, characterized in that The mineral oil is selected from at least one of 11# white oil, 15# white oil and 18# white oil.

9. The emulsion defoamer according to any one of claims 1, 2, 5, 6, 7, and 8, characterized in that The emulsion defoamer also includes 0.01-0.1 parts of bactericide by weight; the bactericide is chloramine.

10. The method for preparing the emulsion defoamer according to any one of claims 1 to 9, characterized in that: The following steps are involved: The defoaming active substance, emulsifier and dispersing medium are heated, mixed and homogenized to prepare an emulsion type defoaming agent.

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