阅读说明：本技术 用于制备烷基硫酸钠干燥物的前驱组合物 (Precursor composition for preparing sodium alkyl sulfate dry product ) 是由 袁志武 罗芳 单量红 于 2021-09-10 设计创作，主要内容包括：本发明涉及用于制备烷基硫酸钠干燥物的前驱组合物,主要解决现有技术中烷基硫酸钠干燥物的前驱组合物在加热干燥过程中pH稳定效果差和干燥除水效率低的问题,本发明通过采用用于制备烷基硫酸钠干燥物的前驱组合物,以重量计,包括：烷基硫酸钠,100份；水,a份,a为20～900；所述的前驱组合物还包括表面活性剂添加剂,所述表面活性剂添加剂包括选自甜菜碱表面活性剂和/或脂肪酸二乙醇酰胺表面活性剂的技术方案,较好地解决了该技术问题,可用于烷基硫酸钠干燥物的生产中。(The invention relates to a precursor composition for preparing an alkyl sodium sulfate dry product, which mainly solves the problems of poor pH stabilizing effect and low drying and dewatering efficiency of the precursor composition of the alkyl sodium sulfate dry product in the prior art in the heating and drying process, and the precursor composition for preparing the alkyl sodium sulfate dry product comprises the following components in parts by weight: 100 parts of sodium alkyl sulfate; water, a, wherein a is 20-900; the precursor composition also comprises a surfactant additive, and the surfactant additive comprises a technical scheme of selecting from betaine surfactants and/or fatty acid diethanolamide surfactants, so that the technical problem is well solved, and the surfactant additive can be used for producing alkyl sodium sulfate dry products.)

1. A precursor composition for preparing a sodium alkyl sulfate dry comprising, by weight:

100 parts of sodium alkyl sulfate;

water, a, wherein a is 20-900;

the precursor composition further comprises a surfactant additive comprising a surfactant selected from a betaine surfactant and/or a fatty acid diethanolamide surfactant.

Preferably, the surfactant additive in the precursor composition is b parts, and b is more than 0 and less than 5.

2. The precursor composition of claim 1, wherein the sodium alkyl sulfate corresponds to formula 1:

R₁is a C8-C20 hydrocarbon group, preferably a C10-C18 hydrocarbon group and/or preferably a straight chain hydrocarbon group and/or preferably a primary hydrocarbon group and/or preferably an alkyl group.

3. The precursor composition of claim 1, wherein the betaine surfactant is according to formula 2:

R₂is a C8-C20 hydrocarbyl, preferably C10-C18 hydrocarbyl and/or preferably straight chain hydrocarbyl and/or preferably primary hydrocarbyl and/or preferably alkyl;

R₃and R₄Independently is C1-C3 alkyl or hydroxyl substituted alkyl;

R₅is C1-C3 alkylene or hydroxy-substituted alkylene;

y is-COO or-SO₃。

4. The precursor composition of claim 1, wherein the fatty acid diethanolamide surfactant is according to formula 3:

R₆is a C7-C20 hydrocarbon group, preferably a C9-C17 hydrocarbon group and/or preferably a straight chain hydrocarbon group and/or preferably a primary hydrocarbon group and/or preferably an alkyl group.

5. The precursor composition of claim 1, wherein the precursor composition is with or without a pH buffer. Preferably, the pH buffer includes at least one selected from the group consisting of an alkali metal salt of carbonic acid, an alkali metal salt of phosphoric acid, and an alkali metal salt of citric acid.

6. Precursor composition according to claim 1, characterized in that the surfactant additive comprises a surfactant selected from betaine surfactants and fatty acid diethanolamide surfactants, preferably in a weight ratio of betaine surfactant to fatty acid diethanolamide surfactant of 0.1 to 10, more preferably of 0.2 to 5.

7. A method for preparing a dried product of sodium alkyl sulfate, comprising:

(1) obtaining a precursor composition according to any one of claims 1 to 6;

(2) and (5) heating to remove water.

8. The method of claim 7, wherein the removing water by heating comprises wiped film drying.

9. The method as set forth in claim 7, wherein the temperature for removing water by heating is 90 to 110 ℃.

10. The method as set forth in claim 7, wherein the pressure for removing water by heating is 80 to 103.3 KPa.

Technical Field

The present invention relates to a precursor composition for producing a dried product of sodium alkyl sulfate and a method for producing a dried product of sodium alkyl sulfate.

Background

Sodium dodecyl sulfate, namely K12, has been widely used in the industries of cosmetics, detergents, textile, paper making, lubrication, pharmacy, building materials, chemical engineering, oil extraction and the like, and at present, the sodium dodecyl sulfate is mainly sold in the market as K12 with two specifications of 30% content and 90% content, while the solid K12 with 90% content is more convenient to transport, store and use and lower in cost, so that the sodium dodecyl sulfate is more widely applied. The solid K12 is obtained by high-temperature dehydration of low-content materials such as liquid or paste materials, but in the high-temperature dehydration process of the sodium dodecyl sulfate, partial hydrolysis is generated due to the fact that moisture cannot be removed in time to generate fatty alcohol and sulfuric acid, and the hydrolysis is further promoted under the acidic condition. In the prior art, in order to inhibit the high-temperature hydrolysis degree of sodium dodecyl sulfate, various salts, such as phosphate, carbonate, citrate and the like, are added into a sodium dodecyl sulfate precursor before high-temperature dehydration, and the pH of the material is controlled to be alkaline about 10. However, these salt buffers have poor pH stabilizing effect during the drying and dehydration process, and excessive use of such non-surface active salt additives can affect the downstream customer applications.

Disclosure of Invention

One of the technical problems to be solved by the present invention is to provide a novel precursor composition for preparing an alkyl sodium sulfate dry product, which has the characteristics of good pH stabilization effect and high water removal efficiency in the process of preparing the alkyl sodium sulfate dry product.

The second technical problem to be solved by the invention is a preparation method of a dried product of sodium alkyl sulfate.

In order to solve one of the above technical problems, the technical solution of the present invention is as follows:

a precursor composition for preparing a sodium alkyl sulfate dry comprising, by weight:

100 parts of sodium alkyl sulfate;

water, a, wherein a is 20-900;

the precursor composition further comprises a surfactant additive comprising a surfactant selected from a betaine surfactant and/or a fatty acid diethanolamide surfactant.

The precursor composition for preparing the alkyl sodium sulfate dry product has the characteristics of good pH stabilizing effect and high water removal efficiency in the heating and drying process due to the surfactant additive.

In the above technical solution, it is preferable that the surfactant additive in the precursor composition is b parts, and b is greater than 0 and less than 5.

In the above technical solutions, b is, by way of non-limiting example, 0.01, 0.02, 0.04, 0.06, 0.08, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.5, and the like. b is more usually 0.2 to 2.

In the above technical solution, specific values of a may be 20, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 100, etc., as non-limiting examples, but a is preferably 30 to 80.

In the above technical solution, the pH of the precursor composition of the present invention is usually adjusted to 8.5-9.5, for example, but not limited to, pH 8.6, 8.7, 8.8, 8.9, 9.0, 9.1, 9.2, 9.3, 9.4, etc.

In the above-mentioned technical solution, it is preferable that the sodium alkyl sulfate conforms to formula 1:

R₁is a C8-C20 hydrocarbon group. For example, but not limited to, R1 is a C9 hydrocarbyl group, a C10 hydrocarbyl group, a C11 hydrocarbyl group, a C12 hydrocarbyl group, a C13 hydrocarbyl group, a C14 hydrocarbyl group, a C15 hydrocarbyl group, a C16 hydrocarbyl group, a C17 hydrocarbyl group, a C18 hydrocarbyl group, a C19 hydrocarbyl group, and the like.

In the above technical solutions, R is preferable₁Is a C10-C18 hydrocarbon group.

In the above technical solutions, R is preferable₁Is a straight chain hydrocarbon group.

In the above technical solutions, R is preferable₁A primary hydrocarbyl group.

In the above technical solutions, R is preferable₁An alkyl group.

In the above technical solution, the betaine surfactant is preferably in accordance with formula 2:

R₂a hydrocarbon group of C8 to C20, such as but not limited to R₂Is a C9 hydrocarbon group, a C10 hydrocarbon group, a C11 hydrocarbon group, a C12 hydrocarbon group, a C13 hydrocarbon group,A C14 hydrocarbon group, a C15 hydrocarbon group, a C16 hydrocarbon group, a C17 hydrocarbon group, a C18 hydrocarbon group, a C19 hydrocarbon group, and the like.

R₃And R₄Independently C1-C3 alkyl or hydroxyl substituted alkyl. Such as but not limited to R₃And R₄Independently methyl, ethyl, propyl, 2-hydroxyethyl, 2-hydroxy-propyl, 3-hydroxy-propyl, 2-methyl-ethyl, and the like.

R₅Is C1-C3 alkylene or hydroxyl substituted alkylene. Such as but not limited to R₅Methylene, ethylene, 2-hydroxy-propylene, and the like.

Y is-COO or-SO₃。

In the above technical solutions, R is preferable₂Is a C10-C18 hydrocarbon group.

In the above technical solutions, R is preferable₂Is a straight chain hydrocarbon group.

In the above technical solutions, R is preferable₂Is a primary hydrocarbyl group.

In the above technical solutions, R is preferable₂Is an alkyl group.

In the above technical solution, the fatty acid diethanolamide surfactant is preferably selected to satisfy formula 3:

R₆a hydrocarbon group of C7 to C20, such as but not limited to R₆Is a C8 hydrocarbon group, a C9 hydrocarbon group, a C10 hydrocarbon group, a C11 hydrocarbon group, a C12 hydrocarbon group, a C13 hydrocarbon group, a C14 hydrocarbon group, a C15 hydrocarbon group, a C16 hydrocarbon group, a C17 hydrocarbon group, a C18 hydrocarbon group, a C19 hydrocarbon group or the like.

In the above technical solutions, R is preferable₆Is a C9-C17 hydrocarbon group.

In the above technical solutions, R is preferable₆Is a straight chain hydrocarbon group.

In the above technical solutions, R is preferable₆Is a primary hydrocarbyl group.

In the above technical solutions, R is preferable₆Is an alkyl group.

In the above-mentioned embodiment, the precursor composition preferably contains or does not contain a pH buffer. For example, but not limited to, the pH buffer includes at least one selected from the group consisting of alkali metal carbonate, alkali metal phosphate, and alkali metal citrate.

In the above technical solution, when the precursor composition contains a pH buffer, the amount of the pH buffer may be 0.1 to 2 parts, such as, but not limited to, 0.12 part, 0.13 part, 0.14 part, 0.15 part, 0.16 part, 0.17 part, 0.2 part, 0.3 part, 0.4 part, 0.5 part, 1 part, 1.5 parts, and the like. The dosage forms of the pH buffer are in accordance with the practices of those skilled in the art, for example: when the pH buffering agent comprises an alkali metal salt of carbonic acid, the alkali metal salt of carbonic acid is used in the amount of sodium carbonate (Na)₂CO₃) And/or sodium bicarbonate (NaHCO)₃) Counting; when the pH buffering agent comprises an alkali metal salt of phosphoric acid, the alkali metal salt of phosphoric acid is used in an amount of phosphoric acid (H)₃PO₄) Counting; when the pH buffering agent comprises an alkali metal salt of citric acid, the alkali metal salt of citric acid is citric acid (C)₆H₈O₇) And (6) counting.

In the above technical solution, it is more preferable that the surfactant additive includes a betaine surfactant and a fatty acid diethanolamide surfactant, and the betaine surfactant and the fatty acid diethanolamide surfactant have an interaction promoting effect in improving pH stability and an interaction promoting effect in improving water removal efficiency.

In the above technical scheme, the weight ratio of the betaine surfactant to the fatty acid diethanolamide surfactant is not particularly limited, and comparable mutual promotion effects can be obtained. By way of non-limiting example only, the weight ratio of betaine surfactant to fatty acid diethanolamide surfactant is 0.1 to 10, more specific non-limiting examples being 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, etc. The weight ratio of the betaine surfactant to the fatty acid diethanolamide surfactant is more preferably 0.2-5.

To solve the second technical problem, the technical solution of the present invention is as follows:

a method for preparing a dried product of sodium alkyl sulfate, comprising:

(1) obtaining a precursor composition according to any of the preceding claims in one of the technical aspects;

(2) and (5) heating to remove water.

The method for reducing the water content of the water-containing alkyl sodium sulfate material has high water removal efficiency and high pH stability in the water removal process.

In the above-mentioned technical solutions, the method of removing water by heating is not particularly limited, but in order to improve the production efficiency, the wiping and drying are industrially included.

In the above technical solution, the temperature for heating to remove water is not particularly limited, and those skilled in the art can reasonably select the temperature without creative efforts. By way of non-limiting example, the temperature for removing water by heating may be 90 to 110 ℃. Within this temperature range, as more specific non-limiting temperature point values, for example, but not limited to, 95 ℃, 100 ℃, 101 ℃, 102 ℃, 103 ℃, 104 ℃, 105 ℃, 106 ℃, and the like are illustrated.

It is known to those skilled in the art that lower pressure for heating to remove water is more beneficial to increase the rate of water removal, but lower pressure below atmospheric pressure increases the cost of manufacturing the required equipment and associated equipment, and higher pressure not only increases the cost of manufacturing the equipment but also reduces the rate of water removal when the pressure is greater than atmospheric pressure, which are all considered by those skilled in the art in view of the specific circumstances, and the reasonable selection of pressure for heating to remove water does not require creative work. By way of non-limiting example, the pressure may be above 80KPa and below atmospheric pressure (103.3KPa), and within this range, by way of non-limiting example, pressure point values may be 85, 90, 95, 100, 101.0 KPa.

Likewise, the time for the removal of water by heating of the aqueous sodium alkyl sulfate material (i.e., the material to be dried) of the present invention can be reasonably determined by those skilled in the art as needed without any creative effort, but as a general known rule, the longer the time for the removal by heating, the more sufficient the removal by heating tends to be. For example, when the heated water removal means employs a wiped film dryer, the residence time of the material to be dried in the wiped film dryer may be, but is not limited to, 20 seconds to 100 seconds, and more specific non-limiting values of residence time points within this residence time range may be 25 seconds, 30 seconds, 35 seconds, 40 seconds, 45 seconds, 50 seconds, 55 seconds, 60 seconds, 65 seconds, 70 seconds, 75 seconds, 80 seconds, 85 seconds, 90 seconds, 95 seconds, and so forth. The residence time in the present embodiment is 50 seconds for all purposes on a scale.

After the precursor composition of the dried alkyl sodium sulfate product is subjected to wiped film drying, the water content of the obtained wiped film dried product in weight percentage can reach 0.5-4%.

The skilled person can make reasonable choices as to the specific process conditions under which the wiped film dryer is operated, without having to resort to inventive work, and all with a comparable technical result. In order to facilitate comparison, the specific process conditions adopted in the specific embodiment of the invention are as follows:

a film scraping motor: three-phase asynchronous motor

Voltage of the wiped film dryer motor: 380V;

frequency of the wiped film dryer motor: 50 HZ;

rotation speed of the wiped film dryer motor: 1480 r/min;

speed ratio of speed reducer of scraping film dryer: 6.54;

total flow of material into the dryer in the specific embodiment: 2000 kg/h;

operating pressure of the wiped film dryer: 95 KPa;

scraping and drying temperature: 105 ℃;

residence time of the material to be dried in the wiped film dryer: for 50 seconds.

In the above technical solution, after the step of drying the scraped film, the treatment method may further include the steps of: and extruding the dried scraped film to obtain strip-shaped extrudate.

Precursor composition acquisition mode

The sodium alkyl sulfate in the precursor composition of the present invention is represented by sodium dodecyl sulfate (K12), and the precursor compositionThe method for obtaining the compound can be as follows: using dodecanol as organic raw material and SO as catalyst₃The obtained dodecyl sulfate is used as sulfonating agent, added with surfactant additive according to the present invention, and optionally other additives such as pH corrosion inhibitor or pH buffer precursor (for example, phosphoric acid can be used when alkali metal salt of phosphoric acid is used as pH buffer component, and citric acid can be used when alkali metal salt of citric acid is used as pH buffer component), and then neutralized with sodium hydroxide solution to obtain mixture, which can be used as precursor composition of the present invention. However, this method is not recommended to use a pH buffer comprising an alkali metal salt of carbonic acid because lauryl sulfate is highly acidic and an alkali metal carbonate releases CO in an acidic environment₂Resulting in a loss of pH buffering capacity.

The sodium alkyl sulfate in the precursor composition of the present invention is represented by sodium dodecyl sulfate (K12), and the precursor composition may be obtained by: using dodecanol as organic raw material and SO as catalyst₃The resulting dodecyl sulfate material is neutralized with sodium hydroxide solution to obtain a mixture, which is then added with the surfactant additive of the present invention, and optionally other additives such as a pH corrosion inhibitor or a pH buffer precursor (e.g., phosphoric acid when an alkali metal salt of phosphoric acid is the pH buffer component, and citric acid when an alkali metal salt of citric acid is the pH buffer component).

The sodium alkyl sulfate in the precursor composition of the present invention is represented by sodium dodecyl sulfate (K12), and the precursor composition may be obtained by: using dodecanol as organic raw material and SO as catalyst₃The resulting mass of lauryl sulfate is used as a sulfonating agent, and then the lauryl sulfate is neutralized with a mixture of the surfactant additive of the present invention, and optionally, other additives such as a pH corrosion inhibitor or a pH buffer precursor (e.g., phosphoric acid when an alkali metal salt of phosphoric acid is the pH buffer component; citric acid when an alkali metal salt of citric acid is the pH buffer component). But this method does not recommend the use of a composition comprising carbonic acidAlkali metal salt pH buffers, since the neutralized material is acidic at the beginning of the neutralization process, alkali metal carbonates are liberated CO₂Resulting in a loss of pH buffering capacity.

The water content of the precursor composition of the dried product of sodium alkyl sulfate and the dried product after heating and dewatering were measured by the Karl Fischer method for measuring the water content of surfactants and detergents in GB/T7380-1995.

The measurement or definition of the pH of the precursor composition used to prepare the sodium alkyl sulfate dry and the dry after heat removal of water is: 10.0g of a sample was weighed and dissolved in 1L of water, and the pH value measured at 25 ℃ was the pH value of the sample.

Based on the measured pH value, the pH decrease rate was calculated according to the following formula:

the rate of decrease in pH (precursor composition pH-dry pH/precursor composition pH). times.100%

The smaller the rate of decrease in pH, the more stable the pH during the removal of water by heating.

The present invention will be described in detail below with reference to specific embodiments.

Detailed Description

In the examples: sodium dodecyl sulfate conforming to the formula 1, R₁Is n-dodecyl; dodecyl dimethyl betaine conforms to the formula 2, R₂Is n-dodecyl radical, R₃And R₄Is methyl, R₅Is methylene and Y is COO.

In the examples and comparative examples, dodecyl sulfate material adopts dodecanol as organic raw material and SO₃Is obtained by a sulfonation method of a sulfonating agent.

[ example 1 ]

1. Preparation of K12 precursor composition

92.6 parts by weight of a lauryl sulfate material (corresponding to 100 parts by weight of sodium lauryl sulfate) was taken, and added with 0.30 part by weight of a 50% citric acid aqueous solution (corresponding to 0.15 part by weight of pure citric acid), 0.67 part by weight of a 30% lauryl dimethyl betaine aqueous solution (corresponding to 0.201 part by weight of pure lauryl dimethyl betaine), and 0.97 part by weight of a 70% coconut oil fatty acid diethanolamide aqueous solution (corresponding to 0.679 part by weight of pure coconut oil fatty acid diethanolamide) under stirring, and then neutralized to pH 8.9 with a 32% sodium hydroxide aqueous solution to obtain a K12 precursor composition having a composition as detected by K12:

100 parts by weight of sodium dodecyl sulfate;

sodium citrate (as citric acid), 0.15 parts by weight;

dodecyl dimethyl betaine, 0.201 weight part;

coconut oil fatty acid diethanolamide, 0.679 weight portions;

37.0 parts by weight of water.

The composition of the K12 precursor composition is presented in table 1 for comparison.

2. Wiped film drying

Continuously feeding the K12 precursor composition into a wiped film dryer at a feeding speed of 2000kg/h, wherein the wiped film drying temperature is 105 ℃, and the operating pressure of the wiped film dryer is 95kPa, wherein the wiped film dryer is connected with a wiped film motor through a speed reducer, the voltage of the wiped film dryer motor is 380V, the frequency of the wiped film dryer motor is 50HZ, the rotating speed of the wiped film dryer motor is 1480r/min, the speed ratio of the wiped film dryer speed reducer is 6.54, and the residence time of the material to be dried in the wiped film dryer is 50 seconds.

The dried K12 obtained after drying in the wiped film dryer had a water content of 2.8 w% and a pH of 7.8.

The K12 dry matter properties are listed in table 2 for comparison.

[ example 2 ]

1. Preparation of K12 precursor composition

92.6 parts by weight of lauryl sulfate (equivalent to 100 parts by weight of sodium lauryl sulfate) was taken, and added with 0.30 part by weight of a 50% citric acid aqueous solution (equivalent to 0.15 part by weight of pure citric acid), 1.35 parts by weight of a 30% lauryl dimethyl betaine aqueous solution (equivalent to 0.405 part by weight of pure lauryl dimethyl betaine), and 0.68 part by weight of a 70% coconut oil fatty acid diethanolamide aqueous solution (equivalent to 0.476 part by weight of pure coconut oil fatty acid diethanolamide) with stirring, and then neutralized to pH 8.8 with a 32% sodium hydroxide aqueous solution to obtain a K12 precursor composition having a composition as measured by the test that the K12 precursor composition had:

100 parts by weight of sodium dodecyl sulfate;

sodium citrate (as citric acid), 0.15 parts by weight;

dodecyl dimethyl betaine, 0.405 weight parts;

coconut oil fatty acid diethanolamide, 0.476 parts by weight;

37.4 parts by weight of water.

The composition of the K12 precursor composition is presented in table 1 for comparison.

2. Wiped film drying

Continuously feeding the K12 precursor composition into a wiped film dryer at a feeding speed of 2000kg/h, wherein the wiped film drying temperature is 105 ℃, and the operating pressure of the wiped film dryer is 95kPa, wherein the wiped film dryer is connected with a wiped film motor through a speed reducer, the voltage of the wiped film dryer motor is 380V, the frequency of the wiped film dryer motor is 50HZ, the rotating speed of the wiped film dryer motor is 1480r/min, the speed ratio of the wiped film dryer speed reducer is 6.54, and the residence time of the material to be dried in the wiped film dryer is 50 seconds.

The dried K12 obtained after drying in the wiped film dryer had a water content of 1.1 w% and a pH of 8.1.

The K12 dry matter properties are listed in table 2 for comparison.

[ example 3 ]

1. Preparation of K12 precursor composition

92.6 parts by weight of lauryl sulfate (equivalent to 100 parts by weight of sodium lauryl sulfate) was taken, and added with 0.30 part by weight of a 50% citric acid aqueous solution (equivalent to 0.15 part by weight of pure citric acid), 1.67 parts by weight of a 30% lauryl dimethyl betaine aqueous solution (equivalent to 0.501 part by weight of pure lauryl dimethyl betaine), and 0.54 part by weight of a 70% coconut oil fatty acid diethanolamide aqueous solution (equivalent to 0.378 part by weight of pure coconut oil fatty acid diethanolamide) under stirring, and then neutralized to pH 8.9 with a 32% sodium hydroxide aqueous solution to obtain a K12 precursor composition having a composition as determined by examination:

100 parts by weight of sodium dodecyl sulfate;

sodium citrate (as citric acid), 0.15 parts by weight;

dodecyl dimethyl betaine, 0.501 weight part;

coconut oil fatty acid diethanolamide, 0.378 parts by weight;

37.5 parts by weight of water.

The composition of the K12 precursor composition is presented in table 1 for comparison.

2. Wiped film drying

Continuously feeding the K12 precursor composition into a wiped film dryer at a feeding speed of 2000kg/h, wherein the wiped film drying temperature is 105 ℃, and the operating pressure of the wiped film dryer is 95kPa, wherein the wiped film dryer is connected with a wiped film motor through a speed reducer, the voltage of the wiped film dryer motor is 380V, the frequency of the wiped film dryer motor is 50HZ, the rotating speed of the wiped film dryer motor is 1480r/min, the speed ratio of the wiped film dryer speed reducer is 6.54, and the residence time of the material to be dried in the wiped film dryer is 50 seconds.

The dried K12 obtained after drying in the wiped film dryer had a water content of 0.9 w% and a pH of 8.5.

The K12 dry matter properties are listed in table 2 for comparison.

[ example 4 ]

1. Preparation of K12 precursor composition

92.6 parts by weight of lauryl sulfate (equivalent to 100 parts by weight of sodium lauryl sulfate) was taken, and added with 0.30 part by weight of a 50% citric acid aqueous solution (equivalent to 0.15 part by weight of pure citric acid), 2.35 parts by weight of a 30% lauryl dimethyl betaine aqueous solution (equivalent to 0.705 part by weight of pure lauryl dimethyl betaine), and 0.25 part by weight of a 70% coconut oil fatty acid diethanolamide aqueous solution (equivalent to 0.175 part by weight of pure coconut oil fatty acid diethanolamide) under stirring, and then neutralized to pH 8.7 with a 32% sodium hydroxide aqueous solution to obtain a K12 precursor composition having a composition as measured by the test that the K12 precursor composition had:

100 parts by weight of sodium dodecyl sulfate;

sodium citrate (as citric acid), 0.15 parts by weight;

dodecyl dimethyl betaine, 0.705 part by weight;

coconut oil fatty acid diethanolamide, 0.175 weight portion;

water, 37.9 parts by weight.

The composition of the K12 precursor composition is presented in table 1 for comparison.

2. Wiped film drying

Continuously feeding the K12 precursor composition into a wiped film dryer at a feeding speed of 2000kg/h, wherein the wiped film drying temperature is 105 ℃, and the operating pressure of the wiped film dryer is 95kPa, wherein the wiped film dryer is connected with a wiped film motor through a speed reducer, the voltage of the wiped film dryer motor is 380V, the frequency of the wiped film dryer motor is 50HZ, the rotating speed of the wiped film dryer motor is 1480r/min, the speed ratio of the wiped film dryer speed reducer is 6.54, and the residence time of the material to be dried in the wiped film dryer is 50 seconds.

The dried K12 obtained after drying in the wiped film dryer had a water content of 2.6 w% and a pH of 7.7.

The K12 dry matter properties are listed in table 2 for comparison.

[ example 5 ]

1. Preparation of K12 precursor composition

Taking 92.6 parts by weight of dodecyl sulfate material (equivalent to 100 parts by weight of lauryl sodium sulfate), adding 0.30 part by weight of citric acid aqueous solution with the weight concentration of 50% (equivalent to 0.15 part by weight of pure citric acid) and 2.94 parts by weight of dodecyl dimethyl betaine aqueous solution with the weight concentration of 30% (equivalent to 0.882 part by weight of pure dodecyl dimethyl betaine) while stirring, and then neutralizing with 32% by weight of sodium hydroxide aqueous solution to the pH value of 8.9 to obtain a K12 precursor composition, wherein the detected K12 precursor composition has the following composition:

100 parts by weight of sodium dodecyl sulfate;

sodium citrate (as citric acid), 0.15 parts by weight;

dodecyl dimethyl betaine, 0.882 weight parts;

38.3 parts by weight of water.

The composition of the K12 precursor composition is presented in table 1 for comparison.

2. Wiped film drying

Continuously feeding the K12 precursor composition into a wiped film dryer at a feeding speed of 2000kg/h, wherein the wiped film drying temperature is 105 ℃, and the operating pressure of the wiped film dryer is 95kPa, wherein the wiped film dryer is connected with a wiped film motor through a speed reducer, the voltage of the wiped film dryer motor is 380V, the frequency of the wiped film dryer motor is 50HZ, the rotating speed of the wiped film dryer motor is 1480r/min, the speed ratio of the wiped film dryer speed reducer is 6.54, and the residence time of the material to be dried in the wiped film dryer is 50 seconds.

The dried K12 product obtained after drying in the wiped film dryer had a water content of 3.4 w% and a pH of 7.1.

The K12 dry matter properties are listed in table 2 for comparison.

[ example 6 ]

1. Preparation of K12 precursor composition

Taking 92.6 parts by weight of dodecyl sulfate material (equivalent to 100 parts by weight of lauryl sodium sulfate), adding 0.30 part by weight of citric acid aqueous solution with the weight concentration of 50% (equivalent to 0.15 part by weight of pure citric acid) and 1.26 parts by weight of coconut oil fatty acid diethanolamide aqueous solution with the weight concentration of 70% (equivalent to 0.882 part by weight of pure coconut oil fatty acid diethanolamide) while stirring, and then neutralizing with 32% by weight of sodium hydroxide aqueous solution to the pH value of 8.8 to obtain a K12 precursor composition, wherein the detected K12 precursor composition has the following composition:

100 parts by weight of sodium dodecyl sulfate;

sodium citrate (as citric acid), 0.15 parts by weight;

coconut oil fatty acid diethanolamide, 0.882 weight portion;

36.6 parts by weight of water.

The composition of the K12 precursor composition is presented in table 1 for comparison.

2. Wiped film drying

Continuously feeding the K12 precursor composition into a wiped film dryer at a feeding speed of 2000kg/h, wherein the wiped film drying temperature is 105 ℃, and the operating pressure of the wiped film dryer is 95kPa, wherein the wiped film dryer is connected with a wiped film motor through a speed reducer, the voltage of the wiped film dryer motor is 380V, the frequency of the wiped film dryer motor is 50HZ, the rotating speed of the wiped film dryer motor is 1480r/min, the speed ratio of the wiped film dryer speed reducer is 6.54, and the residence time of the material to be dried in the wiped film dryer is 50 seconds.

The dried K12 obtained after drying in the wiped film dryer had a water content of 3.6 w% and a pH of 7.3.

The K12 dry matter properties are listed in table 2 for comparison.

[ COMPARATIVE EXAMPLE ]

1. Preparation of K12 precursor composition

92.6 parts by weight of dodecyl sulfate (equivalent to 100 parts by weight of sodium dodecyl sulfate) was taken, and 0.30 part by weight of 50% aqueous citric acid (equivalent to 0.15 part by weight of pure citric acid) was added with stirring, and then neutralized to pH 8.8 with 32% aqueous sodium hydroxide to obtain a K12 precursor composition, which was examined to have a composition of K12:

100 parts by weight of sodium dodecyl sulfate;

sodium citrate (as citric acid), 0.15 parts by weight;

36.2 parts by weight of water.

The composition of the K12 precursor composition is presented in table 1 for comparison.

2. Wiped film drying

Continuously feeding the K12 precursor composition into a wiped film dryer at a feeding speed of 2000kg/h, wherein the wiped film drying temperature is 105 ℃, and the operating pressure of the wiped film dryer is 95kPa, wherein the wiped film dryer is connected with a wiped film motor through a speed reducer, the voltage of the wiped film dryer motor is 380V, the frequency of the wiped film dryer motor is 50HZ, the rotating speed of the wiped film dryer motor is 1480r/min, the speed ratio of the wiped film dryer speed reducer is 6.54, and the residence time of the material to be dried in the wiped film dryer is 50 seconds.

The dried K12 obtained after drying in the wiped film dryer had a water content of 6.9 w% and a pH of 5.3.

The K12 dry matter properties are listed in table 2 for comparison.

It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.

TABLE 1

In the table: t represents dodecyl dimethyl betaine; y represents coconut oil fatty acid diethanolamide, and T/Y represents a calculated value of the weight ratio of dodecyl dimethyl betaine to coconut oil fatty acid diethanolamide.

TABLE 2

	Water content%	pH	A rate of decrease in pH,%
				Example 1	2.8	7.8	12.4
Example 2	1.1	8.1	8.0
				Example 3	0.9	8.5	4.5
Example 4	2.6	7.7	11.5
				Example 5	3.4	7.1	20.2
Example 6	3.6	7.3	17.0
				Comparative example	6.9	5.3	39.8