CN115353892A - Synthesis method of anion and zwitterion composite surfactant - Google Patents

Abstract

The invention belongs to the technical field of daily chemical materials, and discloses a synthetic method of an anion and zwitterion composite surfactant. The synthesis method comprises the following steps: carrying out amidation reaction on fatty acid and amino acid salt at 100-250 ℃ to obtain an anionic surfactant with residual fatty acid, adding N, N-dimethyl-1, 3-propane diamine for continuous reaction to obtain the anionic surfactant containing the fatty amide propyl dimethyl tertiary amine intermediate, adding a quaternization reagent for quaternization reaction or adding an oxidizing agent for oxidation reaction to obtain the anionic and zwitterionic composite surfactant. The method not only effectively solves the problems of low conversion rate and high fatty acid residue existing in the synthesis of the amino acid anionic surfactant by the fatty acid process, but also solves the problem of inconvenient use due to poor low-temperature stability of the prior amino acid surfactant product.

Description

Synthesis method of anion and zwitterion composite surfactant

Technical Field

The invention belongs to the technical field of daily chemical materials, and particularly relates to a synthetic method of an anion and zwitterion composite surfactant.

Background

At present, the scale production of the amino acid surfactant mainly adopts the following two process routes: 1. the Showden Bowman condensation process using acyl chloride as main raw material: fatty acyl chloride and amino acid salt are subjected to amidation reaction in water/organic solvent under alkaline conditions. The process route takes acyl chloride as a raw material, more chloride ions are introduced, a large amount of chlorine-containing wastewater can be generated by removing the chloride ions through a subsequent process, the environment friendliness is poor, and the acyl chloride and an organic solvent belong to dangerous materials, but the reaction efficiency is extremely high and can reach more than 95%, so the industrialization degree is high. Patent EP1156033A describes the synthesis of acidic amino acid surface activity of the Showden Bowman process, deep research is carried out on the solvent phase ratio, the product needs to be desalted and uses an organic solvent, the environmental protection is poor and the process has certain safety risk; patent EP1314717B1 describes the synthesis of neutral amino acid in the Showden Bowman process, comparing the influence of the reaction solvent on the reaction efficiency, introducing chloride ions into the product, and removing salt in the post-treatment to produce a large amount of wastewater, and the same environmental protection problem and raw material safety problem also exist. 2. The direct amidation condensation process with fatty acid as main material includes the following steps: fatty acid and amino acid salt are dehydrated and condensed at high temperature to synthesize the target product in one step. The process has simple reaction, high atom economy and safe and harmless raw materials, but the process has low reaction efficiency and high fatty acid residue in the product, thereby causing difficult industrialization. For example, U.S. Pat. No. 5,54, 96959/U.S. Pat. No. 5,2880219/JP 2002-234868, etc. describe a direct condensation process of fatty acids and sodium methyltaurate, respectively, by optimizing the catalyst, reaction temperature, charge ratio, etc., the yield of the obtained product is only 50-80%, and the residual fatty acids are as high as 20-50%. Alternative processes such as CN102266743A disclose a process for preparing N-fatty acyl amino acid surfactants using oil esters. The method of the invention uses grease to replace acyl chloride to synthesize N-fatty acyl amino acid surfactant, and the grease and sodium amino acid react under the condition of catalyst to generate N-fatty acyl sodium amino acid. The patent technology needs to adopt a carrier metal oxide catalyst, and the product yield cannot be ensured. Patent CN111004156A discloses a method for synthesizing fatty acyl amino acid surfactant by direct method, which comprises the following steps: (1) Adding fatty acid, methylamine and isethionate into a reactor; (2) sealing the reactor, and slowly heating to 150-300 ℃; (3) keeping the temperature to react for 2-10 hours; (4) distilling to remove unreacted methylamine; and (5) treating to obtain a finished product. However, this method also has problems of low product yield and high fatty acid content. Patent CN111072524A discloses a method for preparing fatty acyl amino acid surfactant by high temperature crystallization, adding fatty acid, catalyst and amino acid into a reactor; sealing the reactor, and slowly heating to 200-300 ℃; keeping the temperature to react for 2 to 10 hours; slowly stirring and cooling to below 200 ℃ for crystallization; cooling to 80-100 deg.C, filtering, and recovering filtrate; and treating the filter cake to obtain a finished product. In the patent, excessive fatty acid is removed by centrifugation in the cooling process, so that the content of the fatty acid in the product can be reduced to a certain extent, but the product yield is difficult to ensure.

In addition, the above processes also have common drawbacks: the product is solid at low temperature, the low-temperature stability in a formula application system is poor, and part of the product is seriously precipitated at low temperature, so that the use convenience and the formula stability are seriously influenced.

Disclosure of Invention

In view of the above disadvantages and shortcomings of the prior art, the present invention is primarily directed to a method for synthesizing an anionic and zwitterionic complex surfactant. The method synthesizes the anion and zwitterion compound surfactant, which not only solves the problems of safety and environmental protection brought by an acyl chloride process, but also solves the problem of high fatty acid residue in a fatty acid process, and simultaneously improves the low-temperature stability of amino acid surfactant by compounding with zwitterion surfactant.

Another object of the present invention is to provide a surfactant of anionic and zwitterionic complex type obtained by the above method.

The purpose of the invention is realized by the following technical scheme:

a synthetic method of anion and zwitterion composite surfactant comprises the following steps:

(1) Adding fatty acid and amino acid salt into a reactor, uniformly mixing, and then heating to 100-250 ℃ for amidation reaction to obtain an anionic surfactant of residual fatty acid;

(2) Adding N, N-dimethyl-1, 3-propane diamine into the anionic surfactant with the residual fatty acid in the step (1) to continue reacting to obtain the anionic surfactant containing the fatty amide propyl dimethyl tertiary amine intermediate;

(3) And (3) adding a quaternizing agent into the system obtained in the step (2) for quaternization or adding an oxidizing agent for oxidation to obtain the anion and zwitterion composite surfactant.

Further, in the step (1), the fatty acid is selected from fatty acids having 6 to 22 carbon atoms. The hydrophobic long chain in the fatty acid is a straight chain or a branched hydrophobic long chain, and the hydrophobic long chain is a saturated alkyl or an alkyl with one or more unsaturated groups. Preferably, the fatty acid may be selected from at least one of oleic acid, linoleic acid, linolenic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, coconut oil acid, more preferably at least one of lauric acid and coconut oil acid.

Further, in the step (1), the amino acid salt is an alkali metal salt or an ammonium salt of at least one of sarcosine, alanine, glycine, glutamic acid, methyltaurine, aspartic acid, proline, serine, and histidine. The sodium salt of an amino acid is preferred, and at least one sodium salt of sarcosine, alanine, glycine, glutamic acid, and methyltaurine is more preferred.

Further, the fatty acid and the amino acid salt are added in step (1) at a molar ratio of 1 to 10, preferably 1.5 to 10, more preferably 1.5 to 5. When the molar ratio is lower than 1.5, the viscosity is larger in the reaction process, and the reaction efficiency is low; when the molar ratio is more than 10.

Further, the temperature of the amidation reaction in the step (1) is preferably 150 to 250 ℃, more preferably 150 to 220 ℃; the reaction time is 3 to 10 hours, preferably 5 to 10 hours, more preferably 5 to 8 hours. When the reaction temperature is lower than 150 ℃, the reaction efficiency is low, and the viscosity of the reaction system is high; when the reaction temperature is higher than 250 ℃, the product has the risk of yellowing or decomposition.

Further, the content of active matters in the anionic surfactant of the residual fatty acid in the step (1) is 30-70%, and the content of the residual fatty acid is 30-70%. The contents are all mass percent.

Further, in the step (2), the molar ratio of the N, N-dimethyl-1, 3-propanediamine added to the residual fatty acid is 1 to 3, preferably 1.05 to 2.50, more preferably 1.05 to 2. When the molar ratio is less than 1; when the molar ratio is more than 3, the reaction economy is poor.

Further, the reaction temperature in the step (2) is 150-250 ℃, preferably 170-250 ℃, and more preferably 170-220 ℃; the reaction pressure is 0 to 2MPa, preferably 0 to 1MPa, more preferably 0.5 to 1MPa; the reaction time is 3 to 8 hours, preferably 4 to 8 hours, more preferably 5 to 7 hours. When the reaction temperature is lower than 150 ℃, the reaction efficiency is poor, and when the reaction temperature is higher than 250 ℃, the product has the risk of yellowing or decomposition.

Further, in the anionic surfactant containing the fatty acid amidopropyl dimethyl tertiary amine intermediate in the step (2), the content of fatty acid is 0-5%, and the residue of N, N-dimethyl-1, 3-propane diamine is 0-1%.

Further, the quaternizing agent in the step (3) is sodium chloroacetate, acrylic acid, sodium chlorohydroxypropylsulfonate, 2-hydroxy-1, 3 propane sultone, etc., preferably sodium chloroacetate; the oxidant is hydrogen peroxide, sodium peroxide, peroxyacetic acid, potassium peroxide and the like, and hydrogen peroxide is preferred.

Further, the molar ratio of the quaternizing agent to the fatty amidopropyl dimethyl tertiary amine intermediate in step (3) is 1 to 2, preferably 1.05 to 2, more preferably 1.05 to 1.50; the molar ratio of the oxidizing agent to the fatty amidopropyl dimethyl tertiary amine intermediate is 1-2, preferably 1.05-2, more preferably 1.05-1.50. When the molar ratio of the quaternizing agent is lower than 1. When the molar ratio of the oxidizing agent is less than 1.

Further, the quaternization reaction temperature in the step (3) is 60-95 ℃, preferably 65-95 ℃, and most preferably 80-95 ℃; the reaction time is 3 to 8 hours, preferably 3 to 7 hours, and more preferably 4 to 7 hours; the oxidation reaction temperature is 50-95 ℃, preferably 60-95 ℃, and most preferably 60-80 ℃; the reaction time is 3 to 8 hours, preferably 3 to 7 hours, more preferably 4 to 7 hours. The oxidation reaction temperature is lower than 50 ℃ or higher than 95 ℃, and the reaction effect is poor.

Further, the quaternization reaction or the oxidation reaction in the step (3) is carried out under the condition of a water solvent.

An anionic and zwitterionic composite surfactant is prepared by the method.

Furthermore, the solid content of the anion and zwitterion composite surfactant is 25-50%, the residual quantity of fatty acid is less than 3%, and the product is stable and does not precipitate at the temperature of 0-5 ℃.

Compared with the prior art, the invention has the beneficial effects that:

(1) The invention creatively synthesizes an anion and zwitterion composite surfactant, firstly adopts an amino acid anion surfactant synthesized by a fatty acid process, has obvious advantages compared with products of an acyl chloride process, and effectively avoids the problem of a large amount of waste water caused by salt removal in the acyl chloride process, secondly utilizes unreacted fatty acid in the obtained amino acid anion surfactant to react with N, N-dimethyl-1, 3-propane diamine for further quaternization or oxidation to obtain the anion and zwitterion composite surfactant, not only effectively solves the problems of low conversion rate and high fatty acid residue existing in the synthesis of the amino acid anion surfactant by the fatty acid process, but also solves the problem of inconvenient use due to poor low-temperature stability of the prior amino acid surfactant product.

(2) In the composite surfactant synthesized by the invention, the amino acid anionic surfactant adopts a direct acylation process of fatty acid and amino acid salt, is green and environment-friendly, meets the current requirement of green sustainable development, and simultaneously, the residual fatty acid in the amino acid anionic surfactant is further quaternized or oxidized by reacting with N, N-dimethyl-1, 3-propane diamine, thereby solving the problem of high fatty acid content of the product obtained by the direct acylation process of the fatty acid and the amino acid salt, and simultaneously, the low-temperature stability of the amino acid surfactant is improved by compounding the amino acid anionic surfactant and the amphoteric surfactant.

(3) The invention has no adverse effect on the synthesis of the subsequent zwitterionic surfactant by pre-synthesizing the amino acid anionic surfactant, and can improve the synthesis conversion rate of the zwitterionic surfactant to a certain extent.

Detailed Description

The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto.

Example 1

The preparation method of the sodium cocoyl glycinate and cocamidopropyl betaine composite surfactant comprises the following steps:

(1) 100g of coconut oil acid and 24g of sodium glycinate were added to a four-necked flask equipped with a polytetrafluoroethylene stirring blade, thermometer, condenser and nitrogen inlet, and placed in an oil bath to be heated to 150 ℃ for reaction for 3 hours, and the residual coconut oil acid was 38.3% by HPLC.

(2) 28g of N, N-dimethyl-1, 3-propane diamine is added into the product obtained in the step (1), the reaction temperature is controlled at 190 ℃, the reaction time is 7 hours, and after the reaction is finished, the residual N, N-dimethyl-1, 3-propane diamine is removed.

(3) And (3) adding 310g of deionized water and 28.8g of sodium chloroacetate into the product obtained in the step (2) for carrying out quaternization reaction at the reaction temperature of 90 ℃ for 5 hours to obtain the cocoyl sodium glycinate and cocamidopropyl betaine composite surfactant after the reaction is finished.

The resulting composite surfactant of this example measured 1.52% coconut oil acid residue and the product (approximately 35% solids) was stable at 5 ℃ without precipitation.

Example 2

The preparation method of the lauroyl sodium glycinate and lauroyl propyl betaine composite surfactant provided by the embodiment comprises the following steps of:

(1) 100g of lauric acid and 24g of sodium glycinate were added to a four-necked flask equipped with a polytetrafluoroethylene stirring paddle, a thermometer, a condenser and a nitrogen inlet, and placed in an oil bath to be heated to 150 ℃ for reaction for 3 hours, and the residual coconut oil acid was 40.5% by HPLC.

(2) 30gN, N-dimethyl-1, 3-propane diamine is added into the product obtained in the step (1), the reaction temperature is controlled at 200 ℃, the reaction time is 6 hours, and after the reaction is finished, the residual N, N-dimethyl-1, 3-propane diamine is removed.

(3) And (3) adding 315g of deionized water and 30.5g of sodium chloroacetate into the product obtained in the step (2) for carrying out quaternization reaction at the reaction temperature of 95 ℃ for 6 hours to obtain the composite surfactant of sodium lauroyl glycinate and lauroyl propyl betaine.

The lauric acid residue of the composite surfactant obtained in this example was 1.66%, and the product (about 35% in terms of solid content) was stable at 5 ℃ without precipitation.

Example 3

The preparation method of the composite surfactant of sodium methyl lauroyl taurate and lauramidopropyl betaine in the embodiment comprises the following steps:

(1) 100g of lauric acid and 100.6g of 40% sodium methyltaurate were added to a four-necked flask equipped with a polytetrafluoroethylene stirring paddle, a thermometer, a condenser and a nitrogen inlet, and they were heated to 180 ℃ in an oil bath to react for 5 hours, and the residual lauric acid was 44.1% by HPLC.

(2) Adding 35g of N, N-dimethyl-1, 3-propane diamine into the product obtained in the step (1), controlling the reaction temperature at 190 ℃ and the reaction time to be 5 hours, and removing the residual N, N-dimethyl-1, 3-propane diamine after the reaction is finished.

(3) And (3) adding 450g of deionized water and 36.5g of sodium chloroacetate into the product obtained in the step (2) to carry out quaternization reaction at the reaction temperature of 85 ℃ for 6 hours, and obtaining the composite surfactant of the sodium methyl lauroyl taurate and the lauramidopropyl betaine after the reaction is finished.

The lauric acid residue of the composite surfactant obtained in this example was 1.85%, and the product (about 30% solid content) was stable at 0 ℃.

Example 4

The preparation method of the composite surfactant of sodium methyl lauroyl taurate and lauramidopropylamine oxide in the embodiment comprises the following preparation steps:

(1) 100g of lauric acid and 100.6g of 40% sodium methyltaurate were added to a four-necked flask equipped with a polytetrafluoroethylene stirring paddle, a thermometer, a condenser and a nitrogen inlet, and placed in an oil bath to be heated to 200 ℃ for reaction for 6 hours, and the residual lauric acid was 42.8% by HPLC.

(2) Adding 33.3g of N, N-dimethyl-1, 3-propane diamine into the product obtained in the step (1), controlling the reaction temperature at 180 ℃, reacting for 5 hours, and removing the residual N, N-dimethyl-1, 3-propane diamine after the reaction is finished.

(3) 390g of deionized water and 10.6g of hydrogen peroxide are added into the product obtained in the step (2) for oxidation reaction at 65 ℃ for 5h, and the composite surfactant of the sodium methyl lauroyl taurate and the laurylamidopropylamine oxide can be obtained after the reaction is finished.

The lauric acid residue of the composite surfactant obtained in this example was 2.11%, and the product (about 30% solid content) was stable at 0 ℃.

Example 5

The preparation method of the sodium laurylaminopropionate and laurylamidopropylbetaine composite surfactant of the embodiment comprises the following steps:

(1) 100g of lauric acid and 18.5g of sodium alaninate were added to a four-necked flask equipped with a polytetrafluoroethylene stirring paddle, a thermometer, a condenser and a nitrogen inlet, and placed in an oil bath to be heated to 200 ℃ for reaction for 4 hours, and the residual lauric acid was 45.2% by HPLC.

(2) Adding 32.0g of N, N-dimethyl-1, 3-propane diamine into the obtained product, controlling the reaction temperature at 200 ℃, reacting for 6 hours, and removing the residual N, N-dimethyl-1, 3-propane diamine after the reaction is finished.

(3) And (3) adding 400g of deionized water and 35.8g of sodium chloroacetate into the product obtained in the step (2) to carry out quaternization reaction at the reaction temperature of 90 ℃ for 6h, and obtaining the sodium laurylaminopropionate and laurylamidopropylbetaine composite surfactant after the reaction is finished.

The lauric acid residue of the composite surfactant obtained in this example was 2.55%, and the product (about 30% in terms of solid content) was stable at 5 ℃ without precipitation.

Example 6

The preparation method of the sodium cocamidopropionate and cocamidopropyl amine oxide composite surfactant comprises the following steps:

(1) 100g of coconut oil acid and 22.1g of sodium alanine were added to a four-necked flask equipped with a polytetrafluoroethylene stirring blade, a thermometer, a condenser and a nitrogen inlet, and the flask was heated to 180 ℃ in an oil bath to react for 6 hours, and 46.8% of residual lauric acid was measured by HPLC.

(2) Adding 32.3g of N, N-dimethyl-1, 3-propane diamine into the product obtained in the step (1), controlling the reaction temperature at 180 ℃, reacting for 7 hours, and removing the residual N, N-dimethyl-1, 3-propane diamine after the reaction is finished.

(3) And (3) adding 350g of deionized water and 10.1g of hydrogen peroxide into the product obtained in the step (2) to perform oxidation reaction at the reaction temperature of 60 ℃ for 5h, and obtaining the sodium cocoamidopropionate and cocoamidopropylamine oxide composite surfactant after the reaction is finished.

The resulting composite surfactant of this example measured 2.02% coconut oil acid residue and the product (approximately 30% solids) was stable at 0 ℃ without precipitation.

Comparative example 1

The comparative example is a method for synthesizing sodium methyl lauroyl taurate by taking acyl chloride as a raw material, and comprises the following steps:

100.6g of 40% sodium methyl taurate and 70g of deionized water are added into a five-mouth flask provided with a polytetrafluoroethylene stirring paddle, a thermometer, a pH meter probe and a nitrogen inlet, stirring is started, uniform dispersion is carried out, then 49.6g of lauroyl chloride and 27.5g of 32% sodium hydroxide solution are simultaneously dropwise added into the five-mouth flask, the five-mouth flask is placed in a constant temperature bath at 55 ℃ for reaction for 3h, the residual lauric acid is 1.83% measured by HPLC, the obtained product is pasty fluid at room temperature, a large amount of wastewater is generated by post-treatment desalination, the ratio of the obtained product to the saline wastewater is close to 1, and the environment friendliness is poor. Deionized water is used for adjusting the product to about 30 percent of solid content, the product is seriously separated out at 0 ℃, the low-temperature stability is poor, and the use is inconvenient.

Comparative example 2

The comparative example is a method for preparing sodium lauroyl sarcosinate by using acyl chloride as a raw material, and comprises the following steps:

adding 100g of 35% sodium sarcosinate and 150g of deionized water into a five-mouth flask provided with a polytetrafluoroethylene stirring paddle, a thermometer, a pH meter probe and a nitrogen inlet, starting stirring and dispersing uniformly, then simultaneously dropwise adding 65.6g of lauroyl chloride and 26g of 32% sodium hydroxide solution into the five-mouth flask, placing the five-mouth flask in a constant temperature tank at 15 ℃ for reacting for 3 hours, heating to 80-90 ℃ after the reaction is finished, adjusting the pH of a reaction solution to about 2, removing a water layer, neutralizing an oil layer by 35.7g of 32% sodium hydroxide solution, and adjusting the solid content to about 30% by 160g of deionized water. The residual lauric acid is 0.7% by HPLC, the ratio of the obtained product to the salt-containing wastewater is close to 1.

The results of the above examples and comparative examples 1 to 2 show that the composite surfactant obtained by the method of the present invention has low fatty acid content and excellent low temperature stability, and avoids the use of acyl chloride in the synthesis of amino acid surfactants, thus being environment-friendly.

Comparative example 3

This comparative example is the synthesis of a single cocoamidopropyl betaine zwitterionic surfactant, with the specific steps as follows:

(1) 38.3g of coconut oil acid and 28g of N, N-dimethyl-1, 3-propane diamine are added into a four-neck flask provided with a polytetrafluoroethylene stirring paddle, a thermometer, a condenser and a nitrogen inlet, the reaction temperature is controlled at 190 ℃, the reaction time is 7 hours, and after the reaction is finished, the residual N, N-dimethyl-1, 3-propane diamine is removed.

(2) And (2) adding 310g of deionized water and 28.8g of sodium chloroacetate into the product obtained in the step (1) to carry out quaternization reaction at the reaction temperature of 90 ℃ for 5 hours, and obtaining the cocamidopropyl betaine zwitterionic surfactant after the reaction is finished.

The surfactant from this comparative example measured 4.66% coco acid residue.

As can be seen from the results of example 1 and this comparative example, the invention has no adverse effect on the synthesis of the subsequent zwitterionic surfactant by synthesizing the amino acid anionic surfactant in advance, and can improve the synthesis conversion rate of the zwitterionic surfactant to a certain extent.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.

Claims (10)

1. A synthetic method of anion and zwitterion composite surfactant is characterized by comprising the following steps:

(1) Adding fatty acid and amino acid salt into a reactor, uniformly mixing, and then heating to 100-250 ℃ for amidation reaction to obtain an anionic surfactant with residual fatty acid;

(2) Adding N, N-dimethyl-1, 3-propane diamine into the anionic surfactant with the residual fatty acid in the step (1) to continue reacting to obtain the anionic surfactant containing the fatty amide propyl dimethyl tertiary amine intermediate;

(3) And (3) adding a quaternizing agent into the system obtained in the step (2) to carry out quaternization reaction or adding an oxidizing agent to carry out oxidation reaction to obtain the anion and zwitterion composite surfactant.

2. The method for synthesizing the anionic and zwitterionic composite surfactant according to claim 1, wherein the fatty acid in step (1) is selected from fatty acids with 6-22 carbon atoms; the amino acid salt is alkali metal salt or ammonium salt of at least one of sarcosine, alanine, glycine, glutamic acid, methyl taurine, aspartic acid, proline, serine and histidine; the molar ratio of the fatty acid to the amino acid salt is 1-10.

3. The method for synthesizing the anionic and zwitterionic composite surfactant according to claim 2, wherein the fatty acid is at least one of oleic acid, linoleic acid, linolenic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid and coconut oil acid; the amino acid salt is at least one sodium salt of sarcosine, alanine, glycine, glutamic acid and methyl taurine; the molar ratio of the fatty acid to the amino acid salt is 1.5-10.

4. The method for synthesizing the anionic and zwitterionic composite surfactant according to claim 1, wherein the temperature of the amidation reaction in the step (1) is 150-250 ℃, and the reaction time is 3-10 h.

5. The method for synthesizing the anionic and zwitterionic composite surfactant according to claim 1, wherein the content of active substances in the anionic surfactant of the residual fatty acid in the step (1) is 30-70%, and the content of the residual fatty acid is 30-70%.

6. The method for synthesizing the anionic and zwitterionic composite surfactant according to claim 1, wherein the molar ratio of the N, N-dimethyl-1, 3-propanediamine added in the step (2) to the residual fatty acid is 1-3; the reaction temperature is 150-250 ℃; the reaction pressure is 0-2 Mpa; the reaction time is 3-8 h.

7. The method for synthesizing the anionic and zwitterionic composite surfactant according to claim 1, wherein in the anionic surfactant containing the fatty amidopropyl dimethyl tertiary amine intermediate in the step (2), the content of fatty acid is 0-5%, and the residue of N, N-dimethyl-1, 3-propane diamine is 0-1%.

8. The method for synthesizing the anionic and zwitterionic composite surfactant according to claim 1, wherein the quaternizing agent in the step (3) is sodium chloroacetate, acrylic acid, sodium chlorohydroxypropylsulfonate, 2-hydroxy-1, 3 propane sultone or 1,3 propane sultone; the oxidant is hydrogen peroxide, sodium peroxide, peroxyacetic acid or potassium peroxide; the molar ratio of the quaternizing agent to the fatty amide propyl dimethyl tertiary amine intermediate is 1-2; the molar ratio of the oxidant to the fatty amide propyl dimethyl tertiary amine intermediate is 1-2; the quaternization reaction temperature is 60-95 ℃, and the reaction time is 3-8 h; the oxidation reaction temperature is 50-95 ℃, and the reaction time is 3-8 h; the quaternization reaction or oxidation reaction is carried out under the condition of water solvent.

9. An anionic and zwitterionic complex surfactant obtainable by the process of any one of claims 1 to 8.

10. The anionic and zwitterionic composite surfactant according to claim 9, wherein the anionic and zwitterionic composite surfactant has a solid content of 25-50%, a residual fatty acid content of less than 3%, and is stable and does not precipitate at 0-5 ℃.