阅读说明：本技术 一种液相三氧化硫磺化制备烷基二苯醚磺酸盐的方法 (Method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide ) 是由 李全红 杨效益 郭朝华 李萍 耿卫东 李建波 李慧芳 任晓丹 董辉 卢建强 于 2020-05-18 设计创作，主要内容包括：本发明公开一种液相三氧化硫磺化制备烷基二苯醚磺酸盐的方法,具体为：液相SO<Sub>3</Sub>与烷基二苯醚分别通过有机溶剂稀释成相应的溶液,由进料泵经预热段预热后送至微混合器混合,再进入微通道反应器磺化反应；微通道反应器有数个不等的微混合单元,每个单元内包含数个特殊梭型分散体用于流体流动时将高粘度点剪切分散,便于两种物料剪切混合；磺化段由背压阀控制到一定的压力,防止溶剂挥发,完成后溶剂冷凝回收,磺酸则进一步由碱液中和得到相应的盐溶液。本发明的磺化反应,溶剂与磺化物料始终同在,可以有效降低反应粘度,反应完成后溶剂可回收；微通道反应器的高传质传热系数是高效磺化的保证,产品色泽浅,磺化率高；无返混现象,工业放大效应明显。(The invention discloses a method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide, which comprises the following steps: liquid phase SO 3 Diluting the mixture and alkyl diphenyl ether into corresponding solutions respectively through an organic solvent, preheating the solutions by a feed pump through a preheating section, then sending the preheated solutions to a micro mixer for mixing, and then entering a micro-channel reactor for sulfonation reaction; the microchannel reactor is provided with a plurality of unequal micro-mixing units, and each unit contains a plurality of special shuttle-shaped dispersions for shearing and dispersing high-viscosity points when fluid flows so as to facilitate shearing and mixing of two materials; the sulfonation section is controlled to a certain pressure by a back pressure valve to prevent the solvent from volatilizing, the solvent is condensed and recovered after the solvent is finished, and the sulfonic acid is further neutralized by alkali liquor to obtain a corresponding salt solution. In the sulfonation reaction of the invention, the solvent and the sulfonated material are always in the same place, so that the reaction viscosity can be effectively reduced, and the reaction is finishedThe solvent after the formation can be recovered; the high mass transfer and heat transfer coefficient of the microchannel reactor is guaranteed by high-efficiency sulfonation, the product has light color and high sulfonation rate; no back mixing phenomenon and obvious industrial amplification effect.)

1. A method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide is characterized by comprising the following steps: the sulfonating agent is liquid-phase sulfur trioxide, the sulfonation reactor is a microchannel reactor, alkyl diphenyl ether and the liquid-phase sulfur trioxide are diluted by using a solvent and then fed, the corresponding sulfonic acid is obtained by sulfonation reaction, then the corresponding sulfonate is obtained by alkali neutralization, and the solvent is condensed and recovered;

the reaction equation is as follows:

wherein R is₁Is an alkyl chain of C8-18, R₂H or an alkyl chain of C8-18, M is Na, K or NH₄。

2. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 1, characterized in that: the method specifically comprises the following two steps: sulfonation reaction and neutralization reaction;

(1) and (3) sulfonation reaction:

the liquid-phase sulfur trioxide organic solution and the alkyl diphenyl ether organic solution are quantitatively and stably fed by a first advection feeding pump and a second advection feeding pump, preheated by a coil pipe and then sent to a micro mixer for mixing; wherein the preheating coil and the micro mixer are preheated in a thermostatic water bath, and the preheating temperature is controlled by the temperature of the water bath;

the reaction medium is mixed by a micro mixer and then enters a micro-channel reactor for reaction; cooling water enters the reactor from a cooling water inlet and flows out from a cooling water outlet, and the reaction temperature in the microchannel reactor is automatically adjusted; the heat released by the reaction is taken away by cooling water;

in order to prevent the solvent from gasifying due to the exothermic reaction inside the microchannel reactor, the system pressure is controlled by a back pressure valve; the system pressure is reduced after the reaction medium flows out of the back pressure valve, and the solvent is gasified into gas, so that all products are separated by the gas-liquid separator, and the liquid-phase product flows to the bottom of the gas-liquid separator and flows out of the sulfonated product outlet; the gas phase is discharged from the tail gas outlet to the condenser, condensed into liquid and flows out from the condensed product outlet, and cooling water enters from the cooling water inlet and flows out from the cooling water outlet;

(2) and (3) neutralization reaction:

and (2) carrying out reduced pressure distillation on the sulfonated product obtained in the step (1) to remove the solvent, and neutralizing the sulfonated product with alkali liquor until the pH value is 7.5-10 to obtain a corresponding alkyl diphenyl ether sulfonate aqueous solution.

3. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 2, characterized in that: the raw material tanks of the liquid-phase sulfur trioxide organic solution and the alkyl diphenyl ether organic solution are of closed structures, SO that the volatilization of the solvent and the SO are prevented₃And (4) escaping, supplementing nitrogen through a nitrogen inlet to the raw material tanks, and reducing the pressure of the nitrogen to 0.02MPa at an outlet by a pressure reducing valve so that the two raw material tanks simultaneously keep the same micro-positive pressure.

4. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 2, characterized in that: the SO₃The molar ratio of the alkyl diphenyl ether to the alkyl diphenyl ether is controlled to be 1.5 to 2.05:1, preferably 2.0-2.05: 1;

the mass concentration of the alkyl diphenyl ether is 30-70%;

the SO₃And the solvent of the alkyl diphenyl ether is halogenated alkane.

5. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 4, characterized in that: the SO₃The molar ratio of the alkyl diphenyl ether to the alkyl diphenyl ether is controlled to be 2.0-2.05: 1;

the halogenated alkane solvent comprises dichloromethane, one of 1, 2-dichloroethane or tetrachloroethane, SO₃The solvent is the same as or different from the alkyl diphenyl ether.

6. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 2, characterized in that:

preheating a reaction medium through a constant-temperature water bath, wherein a preheating coil and a micro mixer are soaked in the constant-temperature water bath, and the temperature is controlled to be 25-60 ℃;

the characteristic size of the micro mixer channel is 0.1-2 mm;

the microchannel reactor is divided into 4-20 unequal micro mixing units, the micro mixing units contain 1-4 unequal shuttle-shaped dispersions, the angles of the head ends of the micro mixing units are 10-40 degrees, and the fluids are blocked by the shuttle-shaped dispersions to play a role in shearing and mixing; the reaction temperature is controlled between 30 and 60 ℃.

7. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 6, characterized in that:

preheating a reaction medium through a constant-temperature water bath, and controlling the temperature to be 35-45 ℃;

the characteristic size of the micro mixer channel is 0.2-0.7 mm;

the angle of the head end of the microchannel reactor is 15-30 degrees, and the reaction temperature is controlled at 40-55 ℃.

8. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 2, characterized in that:

the reaction temperature of the microchannel reactor is controlled by cooling water, and the cooling water enters the microchannel reactor through a first cooling water inlet and then flows out through a first cooling water outlet;

the pressure of the sulfonation reaction is regulated by a back pressure valve and is controlled to be 0.1-1.0 MPa;

the temperature of the condenser is automatically adjusted by the temperature and the flow of cooling water, and the temperature is 0-10 ℃.

9. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 8, characterized in that: the sulfonation reaction pressure is 0.2-0.5 MPa.

10. The method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide according to claim 2, characterized in that: the alkali for neutralization is one of sodium hydroxide, potassium hydroxide or ammonia water solution.

Technical Field

The invention relates to a method for preparing alkyl diphenyl ether sulfonate by liquid-phase sulfur trioxide microchannel sulfonation reaction.

Background

Alkyl diphenyl oxide sulfonates are a generic term for a class of anionic surfactants. The molecular structure contains 1-2 charged sulfonic acid groups, an overlapping region with enhanced negative charges is generated between the sulfonic acid groups, and then the higher charge density causes larger attractive force between molecules, so that larger dissolving effect is generated. The unique molecular structure makes the alkyl diphenyl oxide sulfonate possess several characteristics,

the method can be used in the severe oil extraction fields of low-temperature super-concentrated laundry detergent, soil purification, industrial cleaning, chlorine-containing bleaching detergent, high-temperature and high-salt washing and the like.

However, the viscosity difference between the alkyl diphenyl ether sulfonic acid and the raw material alkyl diphenyl ether is very large, so that the viscosity is increased steeply after the alkyl diphenyl ether is sulfonated, and the traditional falling film sulfonation reactor cannot be applied due to material blockage. The mainstream production method at present is still a kettle type reaction, and the method disclosed by Chinese patents CN 1915969A and CN 101503379A is kettle type stirring sulfonation of fuming sulfuric acid, concentrated sulfuric acid or chlorosulfonic acid. The method has the disadvantages of long reaction time, high reaction temperature, difficult heat exchange, easy temperature runaway, incomplete reaction, large waste acid yield, difficult product and waste acid separation and the like. Chinese patent CN107089932A uses a falling film sulfonation reactor and a kettle type stirring combined reaction, the raw material is diluted by adding a solvent, primary sulfonation is performed first, and then sulfonation is supplemented through kettle type stirring, the disadvantages are still long reaction time, incomplete reaction, easy temperature runaway, deep color, and a large amount of low boiling point solvent is lost due to volatilization, the effect of reducing viscosity is limited, and the solvent is easy to cause explosion in an electrostatic demister of a tail gas treatment unit.

Disclosure of Invention

The invention aims to provide a method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide.

The invention provides a method for preparing alkyl diphenyl ether sulfonate by sulfonating liquid-phase sulfur trioxide, wherein the sulfonating agent is liquid-phase sulfur trioxide (SO)₃) The method comprises the following steps of respectively diluting alkyl diphenyl ether and liquid-phase sulfur trioxide by using a solvent, feeding the diluted alkyl diphenyl ether and liquid-phase sulfur trioxide, carrying out sulfonation reaction to obtain corresponding sulfonic acid, neutralizing the sulfonic acid by using alkali to obtain corresponding sulfonate, and condensing and recovering the solvent.

The sulfonation reactor is a microchannel reactor, the microchannel reactor is a chemical process strengthening device, a very large specific surface area is achieved in a channel with the size of micron to millimeter through the principle of laminar diffusion, and data show that when the channel is 1mm, the specific surface area is 1000 m²/m³(ii) a When the channel is 0.1 mm, the specific surface area can reach 10000 m²/m³And the mass and heat transfer effect has obvious advantages.

The reaction equation is as follows:

wherein R is₁Is an alkyl chain of C8-18, R₂H or an alkyl chain of C8-18, M is Na, K or NH₄。

The method specifically comprises the following two steps: sulfonation reaction and neutralization reaction;

(1) and (3) sulfonation reaction:

the liquid-phase sulfur trioxide organic solution and the alkyl diphenyl ether organic solution are quantitatively and stably fed by a first advection feeding pump and a second advection feeding pump, preheated by a preheating coil and sent to a micro mixer for mixing. Wherein, the preheating coil and the micro mixer are preheated in a thermostatic water bath, and the preheating temperature is controlled by the thermostatic water bath.

The two material tanks are of closed structures to prevent solvent volatilization and SO₃And (4) escaping, supplementing nitrogen through a nitrogen inlet to the raw material tanks, and reducing the pressure of the nitrogen to 0.02MPa at an outlet by a pressure reducing valve so that the two raw material tanks simultaneously keep the same micro-positive pressure.

The reaction medium enters the microchannel reactor for reaction after being mixed by the micro mixer. Cooling water enters the reactor from a cooling water inlet, and flows out from a cooling water outlet, so that the reaction temperature in the microchannel reactor is automatically adjusted. The heat released by the reaction is taken away by cooling water.

In order to prevent the solvent from gasifying due to the exothermic reaction inside the microchannel reactor, the system pressure is controlled by a back pressure valve. The system pressure is reduced after the reaction medium flows out of the back pressure valve, and the solvent is gasified into gas, so that all products are separated by the gas-liquid separator, and the liquid-phase product flows to the bottom of the gas-liquid separator and flows out of the sulfonated product outlet; and the gas phase is discharged from the tail gas outlet to the condenser, condensed into liquid and flows out from the condensed product outlet, cooling water enters from the cooling water inlet, and the cooling water flows out from the cooling water outlet.

(2) And (3) neutralization reaction:

and (2) carrying out reduced pressure distillation on the sulfonated product obtained in the step (1) to remove the solvent, and neutralizing the sulfonated product with alkali liquor until the pH value is 7.5-10 to obtain a corresponding alkyl diphenyl ether sulfonate aqueous solution.

Further, the SO₃The molar ratio of the alkyl diphenyl ether to the alkyl diphenyl ether is controlled to be 1.5 to 2.05:1, preferably 2.0-2.05: 1. The mass concentration of the alkyl diphenyl ether is between 30 and 70 percent.

The SO₃And alkyl diphenyl ethers as solvents, e.g. methylene chloride1, 2-dichloroethane or tetrachloroethane, the solvents of which may be the same or different.

The medium is preheated by a constant-temperature water bath, wherein the preheating coil and the micro mixer are soaked in the constant-temperature water bath, and the temperature is controlled to be 25-60 ℃, preferably 35-45 ℃.

The characteristic size of the micro mixer channel is 0.1-2 mm, preferably 0.2-0.7 mm.

The microchannel reactor is divided into 4-20 unequal micro mixing units, contains 1-4 unequal shuttle-shaped dispersions, has a head end angle of 10-40 degrees, preferably 15-30 degrees, and has a shearing and mixing effect due to the blockage of the shuttle-shaped dispersions. The reaction temperature is controlled between 30 and 60 ℃, and preferably 40 to 55 ℃;

the reaction temperature of the microchannel reactor is controlled by cooling water, and the cooling water enters the microchannel reactor through a first cooling water inlet and then flows out through a first cooling water outlet;

the pressure of the sulfonation reaction is regulated by a back pressure valve and is controlled to be 0.1-1.0 MPa, preferably 0.2-0.5 MPa.

The temperature of the condenser is automatically adjusted by the temperature and the flow of cooling water, and the temperature of the condenser is controlled to be 0-10 ℃.

The alkali for neutralization is one of sodium hydroxide, potassium hydroxide or ammonia water solution.

The invention has the beneficial effects that:

(1) the method does not relate to gas-phase sulfonation, does not have tail gas emission (no emission of gas-phase sulfur trioxide and the like), and is environment-friendly; the tail gas treatment equipment can be removed, and the capital investment is low; a high-power Roots blower is not needed, the noise is low, and the energy is saved;

(2) the organic solvent cannot be lost along with tail gas, and the solvent can be recovered, so that the production cost is greatly saved;

(3) the method does not relate to gas-phase sulfonation, namely no oxygen exists in the reaction process, so that the explosion danger of the organic solvent can be fundamentally avoided, and the safety is high; the reactor has no moving equipment, no friction electrification and high safety;

(4) in the reaction and mixing processes, the solvent and the reaction medium are always in the same position, so that the viscosity of the reaction materials can be effectively reduced, and mass transfer is facilitated;

(5) the channels of the micro mixer and the micro channel reactor are in micron order, so that the micro mixer and the micro channel reactor have very large specific surface area, and the mass transfer and heat transfer are more excellent than those of the traditional bubbling reaction; dead angles in the micro mixer and the micro channel reactor are avoided, and the product deposition phenomenon is avoided; the microchannel reactor can be amplified by overlapping a plurality of layers of channels, and the industrial amplification effect is obvious;

(6) the invention has high heat and mass transfer efficiency, can ensure more uniform reaction, has no local temperature runaway and scorching, and has light product color and higher product quality; the reaction process is continuous, and the product quality is not affected in batches;

(7) no back mixing and less side reaction.

Drawings

FIG. 1 is a schematic view of a partial process flow for sulfonation according to the present invention;

FIG. 2 is a schematic view of the micro-mixing unit structure inside the microchannel reactor.

Fig. 3 is a perspective view of a micro-mixing unit inside a microchannel reactor.

In the figure: 1-liquid phase sulfur trioxide organic solution; 2-nitrogen inlet; 3-a first advection feed pump; 4-alkyl diphenyl ether organic solution; 5-a second advection feed pump; 6-preheating a coil pipe; 7-constant temperature water bath; 8-micro mixer; 9-microchannel reactor; 10-a first cooling water inlet; 11-a first cooling water outlet; 12-back pressure valve; 13-a gas-liquid separator; 14-a tail gas outlet; 15-sulfonated product outlet; 16-a condenser; 17-a second cooling water outlet; 18-a second cooling water inlet; 19-a condensed product outlet; 901-a reaction medium; 902-a microreactor; 903-shuttle type dispersion.

Detailed Description

The present invention is further illustrated by, but is not limited to, the following examples.

The method specifically comprises the following two steps: sulfonation reaction and neutralization reaction;

(1) and (3) sulfonation reaction:

the process flow of the sulfonation reaction is shown in fig. 1 and 2, a liquid-phase sulfur trioxide organic solution 1 and an alkyl diphenyl ether organic solution 4 are quantitatively and stably fed by a first advection feed pump 3 and a second advection feed pump 5, preheated by a preheating coil 6 and sent to a micromixer 8 for mixing. Wherein the preheating coil 6 and the micromixer 8 are preheated in a thermostatic water bath 7, and the preheating temperature is controlled by the thermostatic water bath 7.

The two material tanks are of closed structures to prevent solvent volatilization and SO₃And (4) overflowing, supplementing nitrogen to the raw material tanks through a nitrogen inlet 2, and reducing the pressure of the nitrogen to 0.02MPa at an outlet by a pressure reducing valve so that the two raw material tanks simultaneously keep the same micro-positive pressure.

The reaction medium enters the microchannel reactor 9 for reaction after being mixed by the micromixer 8. Cooling water enters the reactor through a first cooling water inlet 10 and then flows out of a first cooling water outlet 11, and the reaction temperature inside the microchannel reactor 9 is automatically adjusted. The heat released by the reaction is taken away by cooling water.

To prevent the solvent from vaporizing due to the exothermic heat of reaction inside the microchannel reactor 9, the system pressure is controlled by a back pressure valve 12. The system pressure is reduced after the reaction medium flows out of the back pressure valve, the solvent is gasified into gas, so all the products are separated by the gas-liquid separator 13, and the liquid phase product flows to the bottom of the gas-liquid separator 13 and flows out of the sulfonated product outlet 15; the gaseous phase is discharged from the tail gas outlet 14 to the condenser 16, condensed into liquid, and flows out from the condensed product outlet 19, and cooling water of the condenser enters from the second cooling water inlet 18 and then flows out from the second cooling water outlet 17.

Aiming at the characteristic that after the alkyl diphenyl ether is sulfonated, high-viscosity groups are easily formed locally and then flow is difficult, 1-4 shuttle-shaped dispersoids 903 are arranged in each micro-mixing unit in the microchannel reactor 9, and the sharp heads of the dispersoids can shear, disperse and reunite quickly flowing reaction materials, so that local hot spots and local high-viscosity points in the reaction materials can be effectively cut, dispersed and reunited, and the materials can be better mixed, and the mixing effect is better;

(2) and (3) neutralization reaction:

and (2) carrying out reduced pressure distillation on the sulfonated product obtained in the step (1) to remove the solvent, and neutralizing the sulfonated product with alkali liquor until the pH value is 7.5-10 to obtain a corresponding alkyl diphenyl ether sulfonate aqueous solution.

Further, the SO₃The molar ratio of the alkyl diphenyl ether to the alkyl diphenyl ether is controlled to be 1.5 to 2.05:1, preferably 2.0-2.05: 1. The mass concentration of the alkyl diphenyl ether is between 30 and 70 percent.

The SO₃And the solvent of the alkyl diphenyl ether is alkyl halide, such as one of dichloromethane, 1, 2-dichloroethane or tetrachloroethane, and the two solvents can be the same or different.

The medium is preheated by a constant-temperature water bath 7, wherein the preheating coil 6 and the micro mixer 8 are both soaked in the constant-temperature water bath 7, and the temperature is controlled between 25 ℃ and 60 ℃, preferably 35 ℃ to 45 ℃.

The characteristic dimension of the channel of the micro mixer 8 is 0.1-2 mm, preferably 0.2-0.7 mm.

The microchannel reactor 9 is divided into 4-20 unequal micro-mixing units, each unit has a structure as shown in fig. 2, and contains 1-4 unequal shuttle-shaped dispersions 123 with head end angles of 10-40 degrees, preferably 15-30 degrees, and the fluids are blocked by the shuttle-shaped dispersions 903 to play a role in shearing and mixing. The reaction temperature is controlled between 30 and 60 ℃, and preferably 40 to 55 ℃;

the reaction temperature of the microchannel reactor 9 is controlled by cooling water, and the cooling water enters the microchannel reactor 9 through a first cooling water inlet 10 and then flows out through a first cooling water outlet 11;

the sulfonation reaction pressure is regulated by a back pressure valve 12 and is controlled between 0.1MPa and 1.0MPa, preferably between 0.2 MPa and 0.5 MPa.

The temperature of the condenser is automatically adjusted by the temperature and the flow of cooling water, and the temperature is 0-10 ℃.

The alkali for neutralization is one of sodium hydroxide, potassium hydroxide or ammonia water solution.

The following examples illustrate the practice of the invention: