Preparation method of stable fatty alcohol emulsion

Abstract

According to the invention, fatty alcohol, paraffin, grease and other substances are used as defoaming active matters, three specified surfactants are compounded to form two composite emulsifiers, and a special emulsification process is adopted, so that the two composite emulsifiers play a synergistic role, and the purpose of more tight combination of a water phase and an oil phase in the emulsion is achieved; meanwhile, a dispersing agent and a thickening agent are added at the end of emulsion synthesis, the stability of the emulsion is further improved, the problem of viscosity change caused by emulsion layering in long-term storage of the emulsion is solved, meanwhile, in the using process, the emulsion defoaming agent has the slow-release defoaming effect, and the stability of the emulsion is improved. The defoaming performance can be maintained for a long time.

Description

Technical Field

[0001] The present invention relates to a method for preparing a stable fatty alcohol emulsion. Since the emulsion belongs to fine chemicals, the present invention belongs to the technical field of fine chemicals. Background Art

[0002] In the papermaking process of the paper industry, the paper-making section is a process of processing pulp into paper, which determines the final forming quality of the paper. With the continuous increase of the paper-making speed of modern paper machines, in order to improve the paper quality, various polymer additives are added. The use of these additives makes the bubbles generated by stirring and adsorbed on the fine fibers in the paper-making system more stable. If these bubbles are not eliminated, the paper quality will be reduced. More likely, the paper machine will break due to bubbles, resulting in a decrease in output and affecting the enterprise's benefits. In addition, the defoamer has a retention and drainage aid effect, thereby reducing fiber loss, avoiding water waste, increasing the recovery rate of the pulp, and having considerable economic benefits. Therefore, the use of defoamer for papermaking is particularly important for the papermaking process. The existing and widely used defoamer for papermaking is a fatty alcohol defoamer, whose main active ingredient is fatty alcohol. By means of an emulsification process, an oil-in-water emulsion is formed. During the storage process of the emulsion, due to the action of van der Waals force and Brownian motion, the oil-phase and water-phase droplets perform random molecular thermal motion, and the mutual collision between particles leads to aggregation and coalescence, which easily causes the instability of the emulsion. At present, the industry focuses on researching the defoaming and antifoaming performance and stability of fatty alcohol emulsions.

[0003] CN101003008B starts from the emulsification process itself, chemically modifies the polyether molecule containing hydroxyl groups as an emulsifier to generate a new end-capped polyether, improves the emulsification efficiency, changes the particle size and coverage rate of the oil-phase particles after emulsification. However, the storage stability of this emulsion is poor at high temperatures; AU2012333911 adds a charged ion assistant to the emulsion system, and at the same time uses a process of step-by-step subsequent addition to make the charge adsorbed on the surface of the oil-phase particles. Through the action of ionic repulsion, the emulsion stability is improved. However, due to the dispersion and low strength of the charge effect itself and its large influence by pH, the storage stability of the emulsion prepared by this method can be improved, but a large amount of charged ion assistants are required, increasing the cost; CN105837835A uses two specified-structured assistants and a special emulsification process to make the two assistants play a synergistic role to achieve the purpose of making the water phase and the oil phase in the emulsion combine more closely, and finally improves the storage stability of the emulsion; CN104946134A uses a special emulsification process. During the emulsification process, the stirring is stopped, and a mixture of W / O and a small amount of water or W / O / W is formed by standing, and then the stirring is restarted to increase the shear force per unit area instantaneously, promoting the formation of O / W emulsion. At the same time, a hydrophilic emulsifier is added dropwise during the standing period to improve the stability of the emulsion; the above patents are all patents for preparing fatty alcohol emulsions, and actively solve the problem of emulsion stability, but do not involve the persistence of the foam suppression performance in the later stage of the fatty alcohol emulsion as an antifoaming agent, that is, the anti-decay performance; WO2011 / 065771 combines the spreadability and emolliency of the oil-in-water type and the skin-moisturizing effect and water resistance effect of the water-in-oil type, and finally prepares a cosmetic composition with a high-content stable oil phase; CN116196225A discloses an oil-in-water-in-oil emulsion cosmetic composition, which is formed by mixing an oil-in-water emulsion and a water-in-oil emulsion. It achieves excellent emulsification stability under various temperature conditions, has excellent usability and moisturizing feeling, and excellent skin absorption rate of active ingredients; CN106659672B provides a composition in the form of an emulsion, with fatty alcohol / animal oil / vegetable oil as the main body, and is formulated with surfactants, specifically including C8-C22 alkyl dimethicone copolyols, dimethicone copolyols and polyoxyalkylenated silicone elastomers. The emulsion can be an oil-in-water-in-oil emulsion or a water-in-oil-in-water emulsion, and the finally formed emulsion has an optimized washability effect while maintaining a good makeup effect. The emulsion products involved in the above patents are all for preparing stable emulsions for cosmetic products to improve the application performance of cosmetics. Summary of the Invention

[0004] The present invention uses substances such as fatty alcohols, paraffin wax, and oils as defoaming active substances, and through the compounding of three specified surfactants, two composite emulsifiers are formed. By adopting a special emulsification process, the two composite emulsifiers play a synergistic role, achieving the purpose of making the combination of the water phase and the oil phase in the emulsion closer, achieving a defoaming slow-release effect and improving the stability of the emulsion. At the same time, a dispersant and a thickener are added at the end of the emulsion synthesis to further improve the emulsion stability, solving the problem of viscosity change caused by emulsion stratification during long-term storage of the emulsion. At the same time, during use, the emulsion defoamer has the effect of slow-release defoaming and can maintain the defoaming performance for a long time.

[0005] The fatty alcohol emulsion of the present invention is composed of the following components: A Defoaming active substance The defoaming active substance is selected from solid hydrocarbons, liquid hydrocarbons, and higher fatty alcohols, and can be used alone or in combination; the defoaming active substance is divided into two parts A1 and A2 for use; the dosage of A1 accounts for 40-80% of the total mass of the defoaming active substance; the dosage accounts for 10-30% of the total mass of the emulsion.

[0006] Solid hydrocarbons are solids at room temperature and are selected from lignite wax, carnauba wax, beeswax, soap wax, microcrystalline wax, rubber protective wax, chlorinated petroleum wax, nitrated petroleum wax, sulfonated petroleum wax, and rust preventive wax.

[0007] Liquid hydrocarbons are substances obtained by hydrogenating the 250-415°C fraction in crude oil and are liquids at room temperature, and are selected from kerosene, diesel oil, machine oil, white oil, liquid wax, alkylbenzene, petrolatum, and naphthenic oil.

[0008] Higher fatty alcohols are C8-30 monohydric saturated fatty alcohols, selected from natural fatty alcohols and synthetic fatty alcohols, and can be used alone or in combination; specifically selected from C8 alcohol, C10 alcohol, C12 alcohol, C14 alcohol, C16 alcohol, C18 alcohol, C20 alcohol, C22 alcohol, C24 alcohol, C26 alcohol, C28 alcohol, and C30 alcohol with a single carbon atom number; mixed fatty alcohols with different carbon atom numbers can also be used, such as C8-C10 alcohol, C8-C14 alcohol, C8-C18 alcohol, C12-C14 alcohol, C12-C18 alcohol, C14-C16 alcohol, C16-C18 alcohol.

[0009] B1. Composite emulsifier The composite emulsifier B1 is obtained by mixing emulsifier B1-1 and emulsifier B1-2, wherein the dosage of B1-1 accounts for 20-50% of the total mass of the composite emulsifier B1; the dosage of the composite emulsifier B1 accounts for 3-10% of the total mass of the emulsion; Among them, B1-1 is a lipophilic emulsifier, selected from sorbitan monostearate, sorbitan monooleate, sorbitan tristearate, sorbitan trioleate, ethylene glycol stearate, ethylene glycol laurate, propylene glycol oleate, propylene glycol stearate, glycerol monostearate, glycerol monolaurate, diethylene glycol monolaurate, pentaerythritol stearate, isooctyl stearate, used alone or in combination; The structural formula of the emulsifier B1-2 is R1O(EO) m H, where R1 is C 11-13 alkyl, and m is an integer from 30 to 80; B2. Composite emulsifier The composite emulsifier B2 is obtained by mixing emulsifier B2-1 and emulsifier B2-2, where the dosage of B2-1 accounts for 20-50% of the total mass of the composite emulsifier B2; the dosage of the composite emulsifier B2 accounts for 3-10% of the total mass of the emulsion; Among them, the emulsifier B2-1 is a hydrophilic emulsifier, selected from polyoxyethylene (20) sorbitan monostearate, polyoxyethylene (20) sorbitan monooleate, polyoxyethylene (20) sorbitan tristearate, polyethylene glycol 2000, polyethylene glycol 4000, polyoxyethylene (20) stearate ether, polyoxyethylene (20) oleate ether, polyoxyethylene (20) stearyl ether, polyoxyethylene (20) castor oil ether, triethanolamine oleate, polyethylene glycol 4000 monooleate, polyethylene glycol 2000 monolaurate, polyethylene glycol 2000 monostearate, used alone or in combination; The structural formula of the emulsifier B2-2 is R1O(EO) m H, where R1 is C 11-13 alkyl, and m is an integer from 30 to 80.

[0010] C. Dispersant The dispersant is alkylaryl sulfonate, selected from sodium alkylbenzene sulfonate, sodium decylbenzene sulfonate, sodium dodecylbenzene sulfonate, sodium tetradecylbenzene sulfonate, sodium hexadecylbenzene sulfonate, sodium octyldiphenyl ether disulfonate, sodium decyldiphenyl ether disulfonate, sodium tetradecyldiphenyl ether disulfonate, sodium hexadecyldiphenyl ether disulfonate. The dosage of the dispersant is 0.1-5% of the total mass of the emulsion.

[0011] D. Water The water is deionized water, which is divided into two parts D1 and D2 for use. Both D1 and D2 are used as the phase inversion liquid of the oil-in-water emulsion, and the dosage is 50-80% of the total mass of the emulsion.

[0012] E. Thickener The thickener can further enhance the emulsion stability and is selected from natural thickeners and synthetic thickeners, specifically selected from xanthan gum, guar gum, polyvinyl alcohol, sodium carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, polymethacrylate, polyacrylic acid, and polyacrylate. Polyacrylic acid is preferred. The dosage of the thickener is 0.1-5% of the total mass of the emulsion.

[0013] The preparation steps of the fatty alcohol emulsion of the present invention are as follows: (1) Heat a specified amount of defoaming active substance A1 to 70-90 °C and mix evenly. Under the insulation state, add compound emulsifier B1 and mix and stir evenly, then dropwise add deionized water D1 at 70-90 °C. After the dropping is completed, stir for a certain time to form mixture M; (2) Heat a specified amount of defoaming active substance A2 to 70-90 °C and mix evenly. Under the insulation state, continue to add compound emulsifier B2 and mix and stir evenly to form mixture N. Add the previously melted and evenly mixed mixture F to the mixture E under the insulation state, stir evenly, then dropwise add deionized water D2 at 70-90 °C. After the dropping is completed, stir for a period of time to form mixture G; (3) Further emulsify mixture G through an emulsifying device, add a dispersant at 70-90 °C, stir evenly and keep warm for a period of time, cool to room temperature, then add a thickener, and stir evenly to obtain the fatty alcohol emulsion. Specific embodiments

[0014] Compound emulsifier B1

[0015]

[0016] Compound emulsifier B2

[0017] Examples of fatty alcohol emulsion Example 1

[0018] (1) Heat a mixture of 4 g of lignite wax and kerosene to 70 °C and mix evenly. Under the insulation state, add 10 g of compound emulsifier B1-I and mix and stir evenly, then dropwise add 30 g of deionized water D1 at 70 °C. After the dropping is completed, stir for a certain time to form mixture M1; (2) Heat a mixture of 6 g of C16 alcohol and C18 alcohol to 70 °C and mix evenly. Under the insulation state, continue to add 8 g of compound emulsifier B2-I and mix and stir evenly to form mixture N1. Add the melted and evenly mixed mixture N1 to the mixture M1 under the insulation state, stir evenly, then dropwise add 35 g of deionized water D2 at 70 °C. After the dropping is completed, stir for a period of time to form mixture G1; (3) Further emulsify the mixture G1 through an emulsifying device, add 5 g of sodium dodecylbenzenesulfonate at 70 °C, stir evenly, keep warm for a period of time, cool to room temperature, add 2 g of polyacrylic acid thickener, and stir evenly to obtain a fatty alcohol emulsion. Example 2

[0019] (1) Heat a mixture of 10 g of rubber protective wax and chlorinated petroleum wax to 80 °C and mix evenly. Under the heat preservation condition, add 6 g of compound emulsifier B1-II, mix and stir evenly, then dropwise add 30 g of deionized water D1 at 80 °C. After the dropping is completed, stir for a certain time to form a mixture M2. (2) Heat a mixture of 10 g of white oil and liquid paraffin to 80 °C and mix evenly. Under the heat preservation condition, continue to add 3 g of compound emulsifier B2-II, mix and stir evenly to form a mixture N2. Add the evenly melted mixture N2 to the mixture M2 under the heat preservation condition, stir evenly, then dropwise add 32 g of deionized water D2 at 80 °C. After the dropping is completed, stir for a period of time to form a mixture G2; (3) Further emulsify the mixture G2 through an emulsifying device, add 4 g of sodium hexadecylbenzenesulfonate at 80 °C, stir evenly, keep warm for a period of time, cool to room temperature, add 5 g of sodium carboxymethylcellulose thickener, and stir evenly to obtain a fatty alcohol emulsion. Example 3

[0020] (1) Heat 18 g of microcrystalline wax to 90 °C and mix evenly. Under the heat preservation condition, add 3 g of compound emulsifier B1-III, mix and stir evenly, then dropwise add 38 g of deionized water D1 at 90 °C. After the dropping is completed, stir for a certain time to form a mixture M3. (2) Heat 12 g of C16-C18 alcohol to 90 °C and mix evenly. Under the heat preservation condition, continue to add 4 g of compound emulsifier B2-III, mix and stir evenly to form a mixture N3. Add the evenly melted mixture N3 to the mixture M3 under the heat preservation condition, stir evenly, then dropwise add 24.8 g of deionized water D2 at 90 °C. After the dropping is completed, stir for a period of time to form a mixture G3; (3) Further emulsify the mixture G3 through an emulsifying device, add 0.1 g of sodium hexylbenzenesulfonate at 90 °C, stir evenly, keep warm for a period of time, cool to room temperature, add 0.1 g of hydroxyethyl cellulose thickener, and stir evenly to obtain a fatty alcohol emulsion. Example 4

[0021] (1) Heat a mixture of 20 g of C8 alcohol and C10 alcohol to 80 °C and mix evenly. Under the heat preservation condition, add 5 g of compound emulsifier B1-IV, mix and stir evenly, then dropwise add 30 g of deionized water D1 at 80 °C. After the dropping is completed, stir for a certain time to form a mixture M4. (2) Heat 9 g of C28 alcohol and C30 alcohol to 85 °C and mix evenly. While maintaining the temperature, continue to add 10 g of compound emulsifier B2-IV and mix and stir evenly to form mixture N4. Add the evenly melted mixture N4 to mixture M4 under the condition of heat preservation, stir evenly, then dropwise add 20 g of deionized water D2 at 85 °C. After the dropping is completed, stir for a period of time to form mixture G4; (3) Further emulsify mixture G4 through an emulsifying device. Add 2 g of sodium hexadecyl diphenyl ether disulfonate at 80 °C, stir evenly and keep warm for a period of time. After cooling to room temperature, add 4 g of polymethacrylate thickener and stir evenly to obtain the fatty alcohol emulsion. Example 5

[0022] (1) Heat 10.5 g of beeswax and saponified wax to 90 °C and mix evenly. While maintaining the temperature, add 3 g of compound emulsifier B1-V and mix and stir evenly, then dropwise add 60 g of deionized water D1 at 90 °C. After the dropping is completed, stir for a certain period of time to form mixture M5 (2) Heat 2.5 g of alkylbenzene to 90 °C and mix evenly. While maintaining the temperature, continue to add 3 g of compound emulsifier B2-V and mix and stir evenly to form mixture N5. Add the evenly melted mixture N5 to mixture M5 under the condition of heat preservation, stir evenly, then dropwise add 20 g of deionized water D2 at 85 °C. After the dropping is completed, stir for a period of time to form mixture G5; (3) Further emulsify mixture G5 through an emulsifying device. Add 0.5 g of sodium octyl diphenyl ether disulfonate at 85 °C, stir evenly and keep warm for a period of time. After cooling to room temperature, add 0.5 g of xanthan gum thickener and stir evenly to obtain the fatty alcohol emulsion. Example 6

[0023] (1) Heat 8.5 g of C12-C14 alcohol to 70 °C and mix evenly. While maintaining the temperature, add 6 g of compound emulsifier B1-VI and mix and stir evenly, then dropwise add 40 g of deionized water D1 at 70 °C. After the dropping is completed, stir for a certain period of time to form mixture M6 (2) Heat 5.5 g of C12-C18 alcohol to 80 °C and mix evenly. While maintaining the temperature, continue to add 4 g of compound emulsifier B2-VI and mix and stir evenly to form mixture N6. Add the evenly melted mixture N6 to mixture M6 under the condition of heat preservation, stir evenly, then dropwise add 30 g of deionized water D2 at 80 °C. After the dropping is completed, stir for a period of time to form mixture G6; (3) Further emulsify mixture G6 through an emulsifying device. Add 3 g of sodium octyl diphenyl ether disulfonate at 80 °C, stir evenly and keep warm for a period of time. After cooling to room temperature, add 3 g of polyacrylate thickener and stir evenly to obtain the fatty alcohol emulsion.

[0024] Comparative Example 1 (1) Heat a mixture of 4 g of montan wax and kerosene to 70 °C and mix evenly. Under the heat preservation condition, add 10 g of sorbitan monostearate and mix and stir evenly. Then, dropwise add 30 g of deionized water D1 at 70 °C. After the dropping is completed, stir for a certain period of time to form mixture M7; (2) Heat a mixture of 6 g of C16 alcohol and C18 alcohol to 70 °C and mix evenly. Under the heat preservation condition, continue to add 8 g of compound emulsifier B2-I and mix and stir evenly to form mixture N1. Add the molten and evenly mixed mixture N1 to the mixture M7 under the heat preservation condition. After mixing evenly, dropwise add 35 g of deionized water D2 at 70 °C. After the dropping is completed, stir for a period of time to form mixture G7; (3) Further emulsify mixture G7 through an emulsifying device. Add 5 g of sodium dodecylbenzenesulfonate at 70 °C, mix evenly and keep warm for a period of time. After cooling to room temperature, add 2 g of polyacrylic acid thickener and mix evenly to obtain the fatty alcohol emulsion. Comparative Example 2

[0025] (1) Heat a mixture of 10 g of rubber protection wax and chlorinated petroleum wax to 80 °C and mix evenly. Under the heat preservation condition, add 6 g of C 12 H 25 O(EO) 80 H and mix and stir evenly. Then, dropwise add 30 g of deionized water D1 at 80 °C. After the dropping is completed, stir for a certain period of time to form mixture M8 (2) Heat a mixture of 10 g of white oil and liquid paraffin to 80 °C and mix evenly. Under the heat preservation condition, continue to add 3 g of compound emulsifier B2-II and mix and stir evenly to form mixture N2. Add the molten and evenly mixed mixture N2 to the mixture M8 under the heat preservation condition. After mixing evenly, dropwise add 32 g of deionized water D2 at 80 °C. After the dropping is completed, stir for a period of time to form mixture G8; (3) Further emulsify mixture G8 through an emulsifying device. Add 4 g of sodium hexadecylbenzenesulfonate at 80 °C, mix evenly and keep warm for a period of time. After cooling to room temperature, add 5 g of sodium carboxymethylcellulose thickener and mix evenly to obtain the fatty alcohol emulsion. Comparative Example 3

[0026] (1) Heat 18 g of microcrystalline wax to 90 °C and mix evenly. Under the heat preservation condition, add 3 g of compound emulsifier B1-III and mix and stir evenly. Then, dropwise add 38 g of deionized water D1 at 90 °C. After the dropping is completed, stir for a certain period of time to form mixture M3 (2) Heat 12 g of C16-C18 alcohol to 90 °C and mix evenly. Under the condition of keeping warm, continue to add 4 g of ethylene glycol stearate and propylene glycol stearate and mix and stir evenly to form mixture N7. Add the evenly melted mixture N7 to the mixture M3 under the condition of keeping warm. After stirring evenly, dropwise add 24.8 g of deionized water D2 at 90 °C. After the dropping is completed, stir for a period of time to form mixture G9; (3) Further emulsify mixture G9 through an emulsifying device. Add 0.1 g of sodium hexylbenzenesulfonate at 90 °C, stir evenly and keep warm for a period of time. After cooling to room temperature, add 0.1 g of hydroxyethyl cellulose thickener and stir evenly to obtain the fatty alcohol emulsion. Comparative Example 4

[0027] (1) Heat 20 g of C8 alcohol and C10 alcohol to 80 °C and mix evenly. Under the condition of keeping warm, add 5 g of compound emulsifier B1-IV and mix and stir evenly. Then, dropwise add 30 g of deionized water D1 at 80 °C. After the dropping is completed, stir for a certain period of time to form mixture M4 (2) Heat 9 g of C28 alcohol and C30 alcohol to 85 °C and mix evenly. Under the condition of keeping warm, continue to add 10 g of C 13 H 27 O(EO) 40 H and mix and stir evenly to form mixture N8. Add the evenly melted mixture N8 to the mixture M4 under the condition of keeping warm. After stirring evenly, dropwise add 20 g of deionized water D2 at 85 °C. After the dropping is completed, stir for a period of time to form mixture G10; (3) Further emulsify mixture G10 through an emulsifying device. Add 2 g of cetyl diphenyl ether disulfonate at 80 °C, stir evenly and keep warm for a period of time. After cooling to room temperature, add 4 g of polymethacrylate thickener and stir evenly to obtain the fatty alcohol emulsion. Comparative Example 5

[0028] (1) Heat 10.5 g of beeswax and saponified wax to 90 °C and mix evenly. Under the condition of keeping warm, add 3 g of compound emulsifier B1-V and mix and stir evenly to form mixture M9 (2) Heat 2.5 g of alkylbenzene to 90 °C and mix evenly. Under the condition of keeping warm, continue to add 3 g of compound emulsifier B2-V and mix and stir evenly to form mixture N5. Add the evenly melted mixture N5 to the mixture M9 under the condition of keeping warm. After stirring evenly, dropwise add 80 g of deionized water D2 at 85 °C. After the dropping is completed, stir for a period of time to form mixture G10; (3) Further emulsify the mixture G10 through an emulsification device, add 0.5 g of sodium octyl diphenyl ether disulfonate at 85 °C, stir evenly and keep warm for a period of time, cool to room temperature, then add 0.5 g of xanthan gum thickener, and obtain the fatty alcohol emulsion after stirring evenly.

[0029] Emulsion stability test Divide the prepared emulsion into three portions and place them at 3 °C, 20 °C, and 40 °C for 8 months for viscosity tracking test. The test method uses an NDJ-8S digital display viscometer, and the test is carried out under the conditions of a 2# rotor and 6 rpm. The specific test results are shown in Table 1 below (viscosity unit: mPa·s): Table 1 Viscosity changes of fatty alcohol emulsion

[0030] Table 1 shows that the oil-in-water emulsion prepared according to the process of the present invention has a small initial viscosity, small viscosity change during storage at various temperatures, and good stability. In the comparative example, problems such as large initial viscosity, stratification, paste formation, and poor high-temperature storage occurred, indicating that the present invention is of great help to the stability of the oil-in-water emulsion at various temperatures. Defoaming and antifoaming performance test

[0031] The performance of the defoamer is determined by the method of circulating bubbling. Add 600 ml of white water to the circulating bubbling device and heat it to the required temperature. Turn on the flow pump, and circulate until the foam volume reaches 300 ml at a flow rate of 8 / L min. Add 6 ul of defoamer, and record the change of the foam volume with time. The smaller the volume within the same time, the better the defoaming and antifoaming performance; the longer the time for the foam to reach 300 ml again, the better the antifoaming performance.

[0032]

[0033]

[0034] The fatty alcohol emulsion prepared by the present invention shows good defoaming and antifoaming performance at 30 °C and 55 °C.

Claims

1. A method for preparing a stable fatty alcohol emulsion, and the preparation method is as follows: (1) Heat a specified amount of defoaming active substance A1 to 70-90 °C and mix evenly. Under the condition of keeping warm, add compound emulsifier B1 and mix and stir evenly, then dropwise add deionized water D1 at 70-90 °C. After the dropping is completed, stir for a certain time to form mixture M; (2) Heat a specified amount of defoaming active substance A2 to 70-90 °C and mix evenly. Under the condition of keeping warm, continue to add compound emulsifier B2 and mix and stir evenly to form mixture N. Add the previously melted and uniform mixture F to mixture E under the condition of keeping warm, stir evenly, then dropwise add deionized water D2 at 70-90 °C. After the dropping is completed, stir for a period of time to form mixture G; (3) Further emulsify mixture G through an emulsifying device, add a dispersant at 70-90 °C, stir evenly and keep warm for a period of time, cool to room temperature and then add a thickener, stir evenly to obtain the fatty alcohol emulsion; Wherein: The defoaming active substance A is selected from solid hydrocarbons, liquid hydrocarbons, and higher fatty alcohols, and can be used alone or in combination; the defoaming active substance is divided into two parts A1 and A2 for use, and the dosage of the defoaming active substance accounts for 10-30% of the total mass of the emulsion; The compound emulsifier B1 is obtained by mixing emulsifier B1-1 and emulsifier B1-2, wherein B1-1 is a lipophilic emulsifier, selected from sorbitan monostearate, sorbitan monooleate, sorbitan tristearate, sorbitan trioleate, ethylene glycol stearate, ethylene glycol laurate, propylene glycol oleate, propylene glycol stearate, glycerol monostearate, glycerol monolaurate, diethylene glycol monolaurate, pentaerythritol stearate, isooctyl stearate, and can be used alone or in combination; the dosage of the compound emulsifier B1 accounts for 3-10% of the total mass of the emulsion; The structural formula of the B1-2 emulsifier is R1O(EO) m H, where R1 is an alkyl group of C 11-13 , m is an integer from 30 to 80; Compound emulsifier B2 is obtained by mixing emulsifier B2-1 and emulsifier B2-2, wherein emulsifier B2-1 is a hydrophilic emulsifier, selected from polyoxyethylene (20) sorbitan monostearate, polyoxyethylene (20) sorbitan monooleate, polyoxyethylene (20) sorbitan tristearate, polyethylene glycol 2000, polyethylene glycol 4000, polyoxyethylene (20) stearyl ether, polyoxyethylene (20) oleyl ether, polyoxyethylene (20) stearyl alcohol ether, polyoxyethylene (20) castor oil ether, triethanolamine oleate, polyethylene glycol 4000 monooleate, polyethylene glycol 2000 monolaurate, polyethylene glycol 2000 monostearate, used alone or in combination; the structural formula of emulsifier B2-2 is R1O(EO) m H, where R1 is C 11-13 alkyl, m is an integer from 30 to 80; the dosage of compound emulsifier B2 accounts for 3-10% of the total mass of the emulsion; The dispersant is alkyl aryl sulfonate; the dosage accounts for 0.1-5% of the total mass of the emulsion; The thickener is selected from natural thickeners and synthetic thickeners; the dosage accounts for 0.1-5% of the total mass of the emulsion; The deionized water is divided into two parts D1 and D2 for use, and both are used as the phase inversion liquid of the water-in-oil emulsion. The total dosage of the deionized water accounts for 50-80% of the total mass of the emulsion.

2. The preparation method of a stable fatty alcohol emulsion according to claim 1, characterized in that, The dosage of A1 in the defoaming active substance accounts for 40-80% of the total mass of the defoaming active substance.

3. The preparation method of a stable fatty alcohol emulsion according to claim 1, characterized in that, Solid hydrocarbons are solids at room temperature and are selected from montan wax, carnauba wax, beeswax, saponification wax, microcrystalline wax, rubber protective wax, chlorinated petroleum wax, nitrated petroleum wax, sulfonated petroleum wax, rust preventive wax; liquid hydrocarbons are substances obtained by hydrogenating the fraction of crude oil at 250 - 415 °C and are liquids at room temperature, and are selected from kerosene, diesel oil, machine oil, white oil, liquid paraffin, alkylbenzene, petrolatum, naphthenic oil; higher fatty alcohols are monohydric saturated fatty alcohols with C8 - 30 carbon atoms and are selected from natural fatty alcohols and synthetic fatty alcohols, used alone or in combination; specifically selected from C8 alcohol, C10 alcohol, C12 alcohol, C14 alcohol, C16 alcohol, C18 alcohol, C20 alcohol, C22 alcohol, C24 alcohol, C26 alcohol, C28 alcohol and C30 alcohol with a single carbon atom number; mixed fatty alcohols with different carbon atom numbers can also be used, such as C8 - C10 alcohol, C8 - C14 alcohol, C8 - C18 alcohol, C12 - C14 alcohol, C12 - C18 alcohol, C14 - C16 alcohol, C16 - C18 alcohol.

4. The preparation method of a stable fatty alcohol emulsion according to claim 1, wherein, The dosage of B1 - 1 in the composite emulsifier B1 accounts for 20 - 50% of the total mass of the composite emulsifier B1.

5. The preparation method of a stable fatty alcohol emulsion according to claim 1, characterized in that, The dosage of B2 - 1 in the composite emulsifier B2 accounts for 20 - 50% of the total mass of the composite emulsifier B2.

6. The preparation method of a stable fatty alcohol emulsion according to claim 1, characterized in that, The dispersant is selected from sodium alkylbenzene sulfonate, sodium decylbenzene sulfonate, sodium dodecylbenzene sulfonate, sodium tetradecylbenzene sulfonate, sodium hexadecylbenzene sulfonate, sodium octyldiphenyl ether disulfonate, sodium decyldiphenyl ether disulfonate, sodium tetradecyldiphenyl ether disulfonate, sodium hexadecyldiphenyl ether disulfonate.

7. The preparation method of a stable fatty alcohol emulsion according to claim 1, characterized in that, The thickener is selected from xanthan gum, guar gum, polyvinyl alcohol, sodium carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, polymethacrylate, polyacrylic acid, polyacrylate, thickener.

8. The preparation method of a stable fatty alcohol emulsion according to claim 1, characterized in that, The thickener is selected from polyacrylic acid.

Images