A pentadecylphenol alkoxyl ether sodium sulfate surfactant and a method for preparing the same

Abstract

The application relates to the technical field of surfactants, in particular to a pentadecyl phenol alkoxyl ether sodium sulfate surfactant and a preparation method thereof. The preparation method of the pentadecyl phenol alkoxyl ether sodium sulfate surfactant comprises the following steps: after pretreatment, cashew nut shell liquid is selectively hydrogenated to obtain pentadecyl phenol with a specific composition; then, alkoxylization reaction is carried out under the condition of an alkaline catalyst to obtain pentadecyl phenol polyalkoxyl ether; and the pentadecyl phenol polyalkoxyl ether is sulfated and neutralized to obtain the pentadecyl phenol alkoxyl ether sodium sulfate surfactant. The surfactant improves the problem that the activity of the surfactant is reduced when the saturation of the pentadecyl phenol is too high or too low; ensures that the final product has good fluidity at low temperature, guarantees the continuity of production, effectively reduces the occurrence of over-sulfation; and simultaneously improves the production efficiency and reduces the cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of surfactants, in particular to a pentadecyl phenol alkoxyl ether sodium sulfate surfactant and a preparation method thereof. BACKGROUND

[0002] Surfactants are a large class of organic compounds, which have the functions of dispersion, wetting, penetration, emulsification, solubilization, and stain removal. With the increasing attention to the environmental performance of materials, higher requirements are put forward for the renewability, biodegradability, and harmful residue control of surfactants. In recent years, renewable raw materials represented by natural cashew nut shell liquid have gradually become a research hotspot to replace petroleum-based raw materials.

[0003] In the prior art, the preparation of traditional surfactants is mostly based on petroleum-based compounds. Such products generally have poor biodegradability due to the presence of branched groups in the molecular structure. When cashew nut shell liquid is used as a raw material to prepare surfactants, on the one hand, the separation and purification of phenolic components in cashew nut shell liquid are difficult in the existing process, resulting in a variety of structures of phenolic components in the raw material, which in turn increases the number of side reactions in subsequent reactions and reduces the performance stability of the product. On the other hand, in the sulfation / sulfonation reaction link from cashew phenol to the target surfactant, if strong reagents such as concentrated sulfuric acid and fuming sulfuric acid are used, not only is it easy to cause multi-site reactions to lead to over-sulfation, which reduces the surface activity of the product, but also a large amount of waste acid is generated, which exacerbates ecological pollution. Although the use of sulfamic acid as a sulfonation agent can reduce waste acid emissions, it has the problems of low sulfonation efficiency and insufficient product purity, and it is easy to release ammonia nitrogen in alkaline application systems, which poses a risk of water eutrophication. These problems seriously limit the sustainable development and application of surfactants. SUMMARY

[0004] In view of the deficiencies in the prior art, the present application provides a preparation method of pentadecyl phenol alkoxyl ether sodium sulfate surfactant.

[0005] In a first aspect, the present application provides a preparation method of pentadecyl phenol alkoxyl ether sodium sulfate surfactant; comprising the following steps:

[0006] (1) Cashew nut shell liquid pretreatment: after the decarboxylated cashew nut shell liquid is treated by an inorganic acid solution and filtered, centrifugation is performed to obtain a pretreated liquid;

[0007] (2) Selective hydrogenation: a metal-based catalyst is added to the pretreated liquid, the temperature is raised to 80-100℃ under a nitrogen atmosphere, hydrogen is introduced, the pressure is controlled to be less than 1.2 MPa, and the hydrogenation is continued until the content of 3-(8,11,14-pentadecatrienyl) phenol is ≤0.5%;

[0008] (3) Distillation purification: the above hydrogenation product is removed from small molecule organic matter by evaporator under vacuum; high purity pentadecyl phenol is obtained by separation through reduced pressure distillation;

[0009] (4) Alkoxylation: alkali catalyst is added in high purity pentadecyl phenol, 1,2-alkylene oxide is introduced under nitrogen atmosphere for alkoxylation reaction, vacuum degassing is carried out after reaction, and cooling is performed;

[0010] (5) Sulfation and continuous neutralization: the product of (4) is introduced into falling film reactor, sulfur trioxide mixed gas is introduced for sulfation reaction, the sulfation product is continuously transferred to neutralizer to adjust pH to 8.0-11.5, and the product is obtained by vacuum degassing again under reduced pressure.

[0011] It can be understood that the alkylation reaction of the present application refers to alkoxylation reaction of a compound with active hydrogen with 1,2-alkylene oxide, the compound with active hydrogen includes alcohol compound, phenolic compound, amine compound, fatty acid compound, 1,2-alkylene oxide includes ethylene oxide, 1,2-propylene oxide, 1,2-butylene oxide; the reaction product alkoxy ether can be copolymer of the same 1,2-alkylene oxide, or block or mixed copolymer of different 1,2-alkylene oxide, including polyoxyethylene ether, polyoxypropylene ether, polyoxybutylene ether, and polyoxyethylene polyoxypropylene block copolymer, polyoxyethylene polyoxypropylene mixed copolymer, polyoxyethylene polyoxybutylene block copolymer, polyoxyethylene polyoxybutylene mixed copolymer, etc.

[0012] The cashew nut shell liquid is bio-based, rich in source and good in degradability. After pretreatment, pentadecyl phenol is obtained from the cashew nut shell liquid as raw material. The long hydrocarbon group structure reduces the substitution activity of the benzene ring site based on steric hindrance, which is conducive to preventing over-sulfation. The double bonds of 3-(8-pentadecenyl)-phenol and 3-(8,11-pentadecadienyl)-phenol are located at positions 8 and 11, and the activity is low, so over-sulfation can be prevented, the reaction stability during continuous production is improved, and the activity of the surfactant is improved. The derived surfactant has weak intermolecular force of unsaturated long chain, and good low-temperature fluidity. The double bond at position 14 of 3-(8,11,14-pentadecatrienyl)-phenol has high activity, and over-sulfation is prone to occur during sulfation. The 3-pentadecyl phenol derivative (such as pentadecyl phenol polyoxyethylene ether sodium sulfate) is prone to solidify into a paste with extremely high viscosity at low temperature, which affects the full contact of the generated 3-pentadecyl phenol polyoxyethylene ether sulfate and lye, so that the activity of the generated surfactant is poor. During continuous neutralization, the production pipeline may also be blocked, resulting in a serious accident of stopping production. Therefore, the pentadecyl phenol is first selectively catalytically hydrogenated. A metal-based catalyst with preferential adsorption activity for the specific double bond at position 14 of the pentadecyl phenol side chain is selected and combined with low-temperature and low-pressure hydrogenation, which tends to hydrogenate the double bond at position 14, and retains the double bonds at positions 8 and 11, thereby retaining the mono-olefin and di-olefin components; over-hydrogenation to generate excessive 3-pentadecyl phenol and other saturated components is avoided. Secondly, sulfur trioxide is selected to perform directional sulfation reaction on the pentadecyl phenol alkoxyl ether (a product obtained by alkylating high-purity pentadecyl phenol with a mono-olefin and di-olefin content of greater than 80%) and continuous neutralization, avoiding the use of concentrated sulfuric acid or oleum in traditional sulfation, which causes serious over-sulfation, and the discontinuous neutralization is prone to cause local over-alkali conditions.

[0013] Therefore, by selective hydrogenation purification, the sulfation reaction occurs at the hydroxyl site, directional sulfation is achieved, by-products are reduced, and a product with good low-temperature fluidity is obtained. Continuous and sufficient alkali neutralization can be achieved, and the activity of the generated surfactant is improved in two aspects. The surfactant is suitable for large-scale continuous production and has high production efficiency. Efficient preparation of surfactants from cashew nut shell liquid to pentadecyl phenol alkoxyl ether sodium sulfate is achieved, and problems such as over-sulfation, product solidification, poor continuous production, dioxane exceeding the standard, and non-renewable raw materials in the prior art are improved.

[0014] The metal-based catalyst in the (2) includes at least one of a nickel-based catalyst, a rhodium-carbon catalyst, or a platinum-carbon catalyst.

[0015] Preferably, the metal-based catalyst is a Raney nickel catalyst.

[0016] More preferably, the metal-based catalyst is a modified Raney nickel catalyst, and the preparation method comprises: mixing ZSM-5 molecular sieve and Raney nickel powder, adding water into a ball mill to form a uniform slurry, drying, calcining at 450-500 DEG C for 1-2 h, obtaining a composite catalyst, then adding an aqueous solution containing H2PtCl6 drop by drop, ultrasonic for 15 min, adding ZnO powder, stirring for 30-45 min to make it uniformly dispersed, calcining at 400-450 DEG C for 1-2 h in N2 atmosphere, obtaining the modified Raney nickel catalyst.

[0017] Further preferably, the metal-based catalyst accounts for 0.2-2.0% of the pretreatment liquid in mass.

[0018] By adopting the above technical scheme, the 14th double bond of 3-(8,11,14-pentadecatrienyl)-phenol has high activity, and after being removed by hydrogenation, the conversion rate of directional sulfation can be improved, and the 14th double bond is prevented from preferentially reacting with sulfur trioxide during subsequent sulfation, thereby avoiding side reactions, reducing over-sulfation, and further reducing the activity of the surfactant. The Raney nickel catalyst has a large specific surface area and a large number of defect sites on the surface, which can serve as efficient active centers for hydrogen dissociation and double bond activation. The pore size of the Raney nickel catalyst matches the spatial size of the pentadecyl chain side chain of cardanol, and the Raney nickel catalyst can selectively adsorb the 14th double bond with small steric hindrance through steric hindrance screening, further strengthening the selectivity and improving the conversion rate.

[0019] Further, the Raney nickel catalyst is modified by compounding, so that the ZSM-5 molecular sieve is mixed with the Raney nickel. The active sites of the Raney nickel preliminarily adsorb the double bond, so that the 14th double bond with higher activity enters the pore channel of the ZSM-5 molecular sieve. Then, the confinement effect of the ZSM-5 molecular sieve is utilized to improve the contact probability of the terminal double bond. Further, the hydrogenation rate of the terminal double bond is improved by Pt doping to ensure the activity of the catalyst. The electronic effect of the ZnO additive can transfer electrons from the oxygen vacancy to the Ni, thereby reducing the central energy of the Ni and weakening the adsorption of the Ni on the 8th and 11th double bonds in the chain, so as to realize selective hydrogenation. Further, the application can provide an efficient and stable catalyst for the selective hydrogenation step, improve the efficiency of the selective hydrogenation and the quality of the product, and is conducive to ensuring the directionality of the subsequent sulfation reaction and improving the performance and quality of the final product, pentadecylphenol alkoxyl ether sodium sulfate. The pretreatment liquid and the metal-based catalyst disclosed in the application can make the selective hydrogenation reaction proceed smoothly, effectively control the content range of each component of 3-pentadecylphenol, ensure that the final product has good fluidity at low temperature, ensure the continuity of production, improve the production efficiency, and reduce the cost. If the pretreatment liquid is too little and the catalyst is too much, the content of 3-pentadecylphenol may increase, the final product pentadecylphenol alkoxyl ether sodium sulfate may easily solidify at low temperature, the continuity and sufficiency of the lye neutralization may be affected, the production pipeline may be blocked, and the production cost may also increase.

[0020] The (3) reduced pressure distillation condition is a temperature of 180-190℃ and an absolute vacuum degree of 4-10Pa.

[0021] The (4) basic catalyst includes one or more of hydroxides, carbonates, C1-C4 alcoholates of alkali metals.

[0022] The (4) vacuum degassing condition is degassing for 45-60min under a vacuum degree of -0.096 to -0.099MPa.

[0023] The (5) sulfur trioxide mixed gas is a mixed gas with a sulfur trioxide volume concentration of 3-8% diluted with dry air, and the dew point of the dry air is below -40℃.

[0024] Preferably, the molar ratio of the (4) product and sulfur trioxide in the (5) is 1:(1.03-1.2).

[0025] By using the above technical solution, the sulfur trioxide is introduced in the form of a mixed gas, which can avoid the reaction from being too violent due to too high a concentration of sulfur trioxide, and thus can avoid the side reaction of benzene ring and side chain over-sulfation, and reduce the activity of the surfactant. The ratio of the (4) product and sulfur trioxide in the present application can improve the sulfation degree of the pentadecyl phenol alkoxyl ether sodium sulfate surfactant, reduce the occurrence of side reactions, and improve the activity performance of the surfactant. Too little sulfur trioxide will lead to incomplete sulfation reaction, and thus increase the unreacted alkoxyl ether in the product, reduce the effective ingredients of the surfactant, affect the activity and performance of the surfactant, and reduce the dispersion and decontamination functions; too much sulfur trioxide will easily cause multi-site reaction to lead to over-sulfation, reduce the surface activity of the product, and possibly generate more by-products, affecting the product quality.

[0026] In some embodiments, in the (5) sulfation and continuous neutralization step, the (4) product is mixed with C8-C14 fatty alcohol polyoxyethylene ether or fatty alcohol alkoxyl ether, and then introduced into a falling film reactor; the mass ratio of the (4) product, C8-C14 fatty alcohol polyoxyethylene ether or fatty alcohol alkoxyl ether is 1:(0.5-2.0).

[0027] Preferably, the C8-C14 fatty alcohol polyoxyethylene ether includes one or more of n-octanol polyoxyethylene ether, iso-octanol polyoxyethylene ether, n-decanol polyoxyethylene ether, iso-decanol polyoxyethylene ether, dodecyl / tetradecyl alcohol polyoxyethylene ether, iso-dodecanol polyoxyethylene ether, and iso-tridecanol polyoxyethylene ether; and the fatty alcohol alkoxyl ether includes one or more of n-octanol alkoxyl ether, iso-octanol alkoxyl ether, n-decanol alkoxyl ether, iso-decanol alkoxyl ether, dodecyl / tetradecyl alcohol alkoxyl ether, iso-dodecanol alkoxyl ether, and iso-tridecanol alkoxyl ether.

[0028] Further preferably, the product of (4), the fatty alcohol polyoxyethylene ether or the fatty alcohol alkoxy ether has a mass ratio of 1:(1.5-1.8).

[0029] The surfactant obtained by adopting the technical scheme has better surface activity, which may be due to, on the one hand, compared with a single pentadecyl benzene long chain, the straight chain hydrophobic long chain of the fatty alcohol can reduce the intermolecular force and improve the flowability of the mixture, which is conducive to continuous neutralization to obtain a fully alkaline neutralized product and improve the activity of the surfactant; on the other hand, the combination of long chain hydrophobic groups with different chain lengths enables the hydrophobic segment to arrange better and form more compact micelles, which is conducive to reducing the surface tension.

[0030] In a second aspect, a pentadecyl phenol alkoxy ether sodium sulfate surfactant is provided, which is prepared according to the preparation method of the pentadecyl phenol alkoxy ether sodium sulfate surfactant.

[0031] It can be understood that the surfactant obtained by the preparation method of the first aspect has all the beneficial effects of the surfactant obtained by the preparation method of the first aspect.

[0032] In summary, the present application has at least one of the following beneficial technical effects:

[0033] 1. The present application realizes efficient preparation of a surfactant from cashew nut shell liquid to pentadecyl phenol alkoxy ether sodium sulfate by selectively catalytically hydrogenating pentadecyl phenol, alkoxylating the obtained unsaturated pentadecyl phenol, and finally directional sulfation of the alkoxy ether and sulfur trioxide, solving the problems of over-sulfation, easy solidification of the product, excessive dioxane, and non-renewable raw materials in the prior art. The polyalkoxy ether chain constitutes the hydrophilic part of the surfactant, which acts together with the hydrophobic pentadecyl group to make the surfactant have good dispersion, emulsification, solubilization, and detergency.

[0034] 2. The present application uses Raney nickel catalyst to selectively hydrogenate 3-(8,11,14-pentadecatrienyl)-phenol, the micropore size in the structure matches the spatial size of the pentadecyl side chain of cardanol, and can screen and adsorb the 14-position double bond with small steric hindrance through steric hindrance, further strengthening the selectivity and improving the conversion rate.

[0035] 3. The present application obtains a surfactant with higher activity by sulfating the mixture of pentadecyl phenol polyalkoxy ether and fatty alcohol polyoxyethylene ether or fatty alcohol alkoxy ether obtained by a specific preparation method and continuously neutralizing. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is the HNMR chart of the sodium compound of pentadecylphenol polyoxyethylene (8) ether sulfate prepared in Example 1.

[0037] Figure 2 is a partial enlarged view of Figure 1

[0038] Figure 3 is the POS positive ion mode and NEG negative ion mode MS chart of the sodium compound of pentadecylphenol polyoxyethylene (4) ether sulfate prepared in Example 2. DETAILED DESCRIPTION

[0039] The sulfuric acid solution in the application is purchased from Aldrich; the ZSM-5 molecular sieve is purchased from Shandong Qilu Huaxin High-tech Co., Ltd., the Raney nickel catalyst is purchased from Dalian Zhenhao Catalyst Technology Co., Ltd.; 1,2-epoxyethane is purchased from Jiangsu Ok Chemical Co., Ltd.; decarboxylation cashew shell liquid is from Nai Su (Mozambique) Individual Company; and other raw materials are commercially available.

[0040] Preparation Example 1

[0041] Preparation of modified Raney nickel catalyst: 25 g of ZSM-5 molecular sieve was mixed with 10 g of Raney nickel powder, 10 ml of water was added and ball-milled for 1 h to form a uniform slurry, which was dried at 100 ℃ for 6 h and then calcined at 450 ℃ for 2 h to obtain a composite catalyst. Then 0.5 g of H2PtCl6 was added dropwise to 15 ml of water to form an aqueous solution, which was ultrasonically treated for 15 min. 2 g of ZnO powder was added and stirred for 30 min to make it uniformly dispersed. The modified Raney nickel catalyst was obtained by calcining at 400 ℃ for 1 h under N2 atmosphere. Example 1

[0042] ​A preparation method of pentadecyl phenol alkoxyl ether sodium sulfate surfactant: 150 kg of decarboxylation cashew shell liquid was put into a reaction kettle, 300 g of 50% sulfuric acid solution was added, stirring was carried out to heat to 80℃, and then continuous stirring was carried out for 30 min, 200 mesh and 500 mesh stainless steel filter screens were connected in series for filtration, and then a butterfly centrifugal filter was used for high-speed centrifugal filtration, the obtained pretreated liquid was transferred to a hydrogenation device, 1% of the pretreated liquid by mass of Raney nickel catalyst was added, nitrogen was used to replace the air in the device, so that the oxygen content was <100 ppm, the temperature was increased to 85℃, hydrogen was continuously introduced, the pressure in the device was controlled to be less than 1.2 MPa, after 780 g of hydrogen was introduced, the hydrogen introduction was stopped, when the pressure in the device was ≤0.2 MPa, the stirring was stopped, nitrogen was introduced for 30 min for purging, the catalyst was removed by filtration, and the hydrogenation product 3-(8,11,14-pentadecatrienyl)-phenol was measured by HPLC to have a content of 0.2%, the obtained hydrogenation product was preheated to 170℃, small molecular organic matter was removed by a thin film evaporator with a vacuum degree of 100 Pa, and then heating was carried out to 180℃, and then the distillation product pentadecyl phenol was obtained by adjusting the vacuum degree of a short path evaporator to 4 Pa.

[0043] 60.2 kg of the distillation product was put into an alkoxylation reaction kettle, 260 g of a potassium hydroxide solution with a concentration of 40% was added, the temperature was increased to 110℃, vacuum dehydration was carried out for 40 min, the vacuum degree was -0.099 MPa, the water content was tested by sampling to be equal to 0.05%, after the dehydration was completed, nitrogen was used to replace the air in the kettle to make the oxygen content <100 ppm, the temperature was increased to 130℃, 70.4 kg of ethylene oxide was continuously introduced, the reaction temperature was controlled to be 130℃ during the period, after the ethylene oxide was completely introduced, the material temperature was maintained, the reaction was continuously carried out for 60 min, vacuum degassing was carried out for 60 min, the vacuum degree was -0.099 MPa, dioxane was tested by sampling, and the dioxane content was less than 10 ppm, after the vacuum was ended, the pH was adjusted to 7 by adding acetic acid, and the pentadecyl phenol polyoxyethylene (8) ether was obtained.

[0044] 132 kg of the pentadecyl phenol polyoxyethylene (8) ether was introduced into a falling film reactor, and a mixed gas of sulfur trioxide diluted with dry air with a volume concentration of 5% was introduced at the same time, wherein the dew point of the dry air was -40℃, so that the molar ratio of the pentadecyl phenol polyoxyethylene (8) ether and the sulfur trioxide was 1:1.1, a sulfation reaction was carried out, the sulfation degree was tested by sampling, the sulfation product was continuously transferred to a neutralizer, 2.5% sodium hydroxide solution was continuously introduced for neutralization, the pH value was controlled to be 10.5, the product was continuously introduced into a stripping tower, vacuum was extracted at 50℃, after the dioxane content was less than 10 ppm, a proper amount of deionized water was added to adjust the solid content of the product to 75%, and the pentadecyl phenol alkoxyl ether sodium sulfate surfactant was obtained. Example 2

[0045] A preparation method of pentadecyl phenol alkoxyl ether sodium sulfate surfactant: 150 kg of decarboxylation cashew shell liquid is put into a reaction kettle, 300 g of 50% sulfuric acid solution is added, stirring is carried out to heat to 80℃, and then continuous stirring is carried out for 30 min, 200 mesh and 500 mesh stainless steel filter screens are connected in series for filtration, and then a butterfly type centrifugal filter is used for filtration, the obtained pretreated liquid is transferred to a hydrogenation device, 1% of the pretreated liquid in mass of Raney nickel catalyst is added, nitrogen is used to replace the air in the device, so that the oxygen content is less than 100 ppm, heating is carried out to 85℃, hydrogen is continuously introduced to control the pressure in the device to be less than 1.2 MPa, after 780 g of hydrogen is introduced, hydrogen introduction is stopped, when the pressure in the device is less than or equal to 0.2 MPa, stirring is stopped, and nitrogen is introduced for purging for 30 min, the catalyst is removed by filtration, and the hydrogenation product 3-(8, 11, 14-pentadecatrienyl)-phenol is measured by HPLC to have a content of 0.2%, the hydrogenation product is heated to 170℃, small molecule organic matter is removed by a thin film evaporator with a vacuum degree of 100 Pa, and then heating is carried out to 180℃, the vacuum degree of a short path evaporator is adjusted to 4 Pa, and the distillation product pentadecyl phenol is obtained.

[0046] 60.2 kg of the distillation product is put into an alkoxylation reaction kettle, 260 g of 40% potassium hydroxide solution is added, heating is carried out to 110℃, vacuum dehydration is carried out for 40 min, the vacuum degree is -0.099 MPa, the water content is tested by sampling to be equal to 0.05%, after the dehydration is completed, nitrogen is used to replace the air in the kettle to make the oxygen content in the kettle less than 100 ppm, heating is carried out to 130℃, 35.2 kg of ethylene oxide is continuously introduced, the reaction temperature is controlled to be 130℃ during the period, after the ethylene oxide is completely introduced, the material temperature is maintained, and the reaction is continuously carried out for 60 min, vacuum degassing is carried out for 60 min, the vacuum degree is -0.099 MPa, dioxane is tested by sampling, and the dioxane content is less than 10 ppm, after the vacuum is ended, the pH is adjusted to 7 by adding acetic acid, and the pentadecyl phenol polyoxyethylene (4) ether is obtained.

[0047] 47.7 kg of pentadecyl phenol polyoxyethylene (4) ether and 84.3 kg of dodecyl / tetradecyl alcohol polyoxyethylene (2) ether are mixed and introduced into a falling film reactor, and a mixed gas of sulfur trioxide diluted with dry air with a volume concentration of 5% is introduced at the same time, wherein the dew point of the dry air is -40℃, so that the molar ratio of the pentadecyl phenol polyoxyethylene (4) ether and the dodecyl / tetradecyl alcohol polyoxyethylene (2) ether mixture to sulfur trioxide is 1:1.1, and then the sulfation reaction is carried out, the sulfation degree is tested by sampling, and then the sulfation product is continuously transferred to a neutralizer, 2.5% sodium hydroxide solution is continuously introduced for neutralization, the pH value is controlled to be 10.5, the product is continuously introduced into a stripping tower, vacuum is extracted at 50℃, when the dioxane content is less than 10 ppm, a proper amount of deionized water is added to adjust the solid content of the product to 75%, and the pentadecyl phenol alkoxyl ether sodium sulfate surfactant is obtained. Referring to Figure 3The positive ion mode mass spectrum and the negative ion mode mass spectrum of the sodium pentadecylphenol polyoxyethylene (4) ether sulfate. Example 3

[0048] A preparation method of a pentadecylphenol alkoxy ether sodium sulfate surfactant: 150 kg of decarboxylated cashew shell liquid was put into a reaction kettle, 300 g of 50% sulfuric acid solution was added, stirring was carried out to raise the temperature to 80°C, and then stirring was continued for 30 min. A 200 mesh and a 500 mesh stainless steel filter screen were connected in series for filtration, and then a butterfly centrifugal filter was used for filtration. The obtained pretreated liquid was transferred to a hydrogenation device, 1% of the pretreated liquid in mass was added as a Raney nickel catalyst, nitrogen was used to replace the air in the device to make the oxygen content <100 ppm, the temperature was raised to 85°C, hydrogen was continuously introduced to control the pressure in the device to be less than 1.2 MPa, after 780 g of hydrogen was introduced, the hydrogen introduction was stopped, the stirring was stopped when the pressure in the device was ≤0.2 MPa, and nitrogen was introduced for 30 min for purging. The catalyst was removed by filtration, and the content of 3-(8,11,14-pentadecatrienyl)-phenol in the hydrogenated product was measured by HPLC to be equal to 0.2%. The hydrogenated product was heated to 170°C, small molecular organic matter was removed by a thin film evaporator with a vacuum degree of 100 Pa, and then the temperature was raised to 180°C. The distillation product pentadecylphenol was obtained by adjusting the vacuum degree of a short path evaporator to 4 Pa.

[0049] 60.2 kg of the distillation product was put into an alkoxylation reaction kettle, 260 g of a 40% concentration potassium hydroxide solution was added, the temperature was raised to 110°C, vacuum dehydration was carried out for 40 min, the vacuum degree was -0.099 MPa, the water content was tested by sampling to be equal to 0.05%, after the dehydration was completed, nitrogen was used to replace the air in the kettle to make the oxygen content <100 ppm, the temperature was raised to 130°C, 52.8 kg of ethylene oxide was continuously introduced, the reaction temperature was controlled to be 130°C during the period, after the ethylene oxide was completely introduced, the material temperature was maintained, and the reaction was continued for 60 min. Vacuum degassing was carried out for 60 min, the vacuum degree was -0.099 MPa, the dioxane content was tested by sampling to be less than 10 ppm, after the vacuum was ended, the pH was adjusted to 7 by adding acetic acid, and the pentadecylphenol polyoxyethylene (6) ether was obtained.

[0050] Mix 56.5 kg of pentadecyl phenol polyoxyethylene (6) ether and 45.0 kg of isodecyl alcohol polyoxypropylene (2) polyoxyethylene (4) ether, and then pass into a falling film reactor, while passing a mixed gas of sulfur trioxide diluted with dry air, the dew point of which is -40℃, at a volume concentration of 5%, so that the molar ratio of pentadecyl phenol polyoxyethylene (6) ether and isodecyl alcohol polyoxypropylene (2) polyoxyethylene (4) ether to sulfur trioxide is 1:1.1, to carry out sulfation reaction, then take samples to measure the degree of sulfation, and then continuously transfer the sulfated product to a neutralizer, continuously pass 2.5% sodium hydroxide solution to carry out neutralization, control the pH value to be 10.5, and then continuously pass the product into a stripping tower, vacuumize at 50℃, and after the dioxane content is less than 10 ppm, add appropriate amount of deionized water to adjust the solid content of the product to 75%, to obtain pentadecyl phenol alkoxy ether sodium sulfate surfactant. Example 4

[0051] A preparation method of pentadecyl phenol alkoxy ether sodium sulfate surfactant: put 150 kg of decarboxylated cashew shell liquid into a reaction kettle, add 300 g of 50% sulfuric acid solution, stir and heat to 80℃, and then continuously stir for 30 min, filter through 200 mesh and 500 mesh stainless steel filter screens in series, and then filter through a butterfly centrifugal filter at high speed, to obtain pretreated liquid which is transferred to a hydrogenation device, 1% of the pretreated liquid by mass of Raney nickel catalyst is added, the device is replaced with nitrogen to make the oxygen content <100 ppm, heated to 85℃, continuously pass in hydrogen, control the pressure in the device to be less than 1.2 MPa, after passing in 780 g of hydrogen, stop passing in hydrogen, when the pressure in the device is ≤0.2 MPa, stop stirring, pass in nitrogen for 30 min, remove the catalyst by filtration, and use HPLC to measure that the content of hydrogenated product 3-(8,11,14-pentadecatrienyl)-phenol is equal to 0.2%, the obtained hydrogenated product is preheated to 170℃, first remove small molecular organic matter through a thin film evaporator with a vacuum degree of 100 Pa, and then heated to 180℃, and then pass through a short path evaporator with an adjusted vacuum degree of 4 Pa, to obtain distillation product pentadecyl phenol;

[0052] Take 60.2 kg distillate into the alkoxylation reactor, then add 280 g of 40% concentration potassium hydroxide solution, heat to 110°C, vacuum dehydration for 40 min, vacuum degree -0.099 MPa, take sample test water content equal to 0.05%, after dehydration, nitrogen replacement to the oxygen content in the kettle <100 ppm, then heat to 120°C, first continuously pass in 69.6 kg of propylene oxide, control the reaction temperature at 130°C during the period, after the propylene oxide is completely passed in, keep the material temperature, continue to react for 180 min, then continuously pass in 8.8 kg of ethylene oxide, control the reaction temperature at 130°C during the period, after the ethylene oxide is completely passed in, keep the material temperature at 130°C, continue to react for 60 min, then vacuum degassing for 60 min, vacuum degree -0.099 MPa, take sample test dioxane, dioxane content less than 10 ppm, after the vacuum is finished, add acetic acid to adjust the pH to 7, then pentadecyl phenol polyoxypropylene (6) polyoxyethylene (2) ether is obtained;

[0053] Take 73.7 kg of pentadecyl phenol polyoxypropylene (6) polyoxyethylene (2) ether into the falling film reactor, and simultaneously pass in a mixed gas of sulfur trioxide diluted with dry air with a volume concentration of 5%, wherein the dew point of the dry air is -40°C, so that the molar ratio of pentadecyl phenol polyoxypropylene (6) polyoxyethylene (2) ether and sulfur trioxide is 1:1.1 to carry out sulfation reaction, then take sample to measure the sulfation degree, continuously transfer the sulfation product to the neutralizer, continuously pass in 2.5% sodium hydroxide solution for neutralization, control the pH value to be 10.5, then continuously pass the product into the stripping tower, vacuumize at 50°C, after the dioxane content is less than 10 ppm, add appropriate amount of deionized water to adjust the product solid content to 75%, then pentadecyl phenol alkoxy ether sodium sulfate surfactant is obtained. Example 5

[0054] A preparation method of pentadecyl phenol alkoxyl ether sodium sulfate surfactant: 150 kg of decarboxylation cashew shell liquid is put into a reaction kettle, 300 g of 50% sulfuric acid solution is added, stirring is carried out to heat to 80℃, and then continuous stirring is carried out for 30 min, 200 mesh and 500 mesh stainless steel filter screens are connected in series for filtration, and then a butterfly centrifugal filter is used for high-speed centrifugal filtration, the obtained pretreated liquid is transferred to a hydrogenation device, 1% of the pretreated liquid in mass of Raney nickel catalyst is added, nitrogen is used to replace the air in the device, so that the oxygen content is less than 100 ppm, heating is carried out to 85℃, hydrogen is continuously introduced, the pressure in the device is controlled to be less than 1.2 MPa, after 780 g of hydrogen is introduced, hydrogen introduction is stopped, when the pressure in the device is less than or equal to 0.2 MPa, stirring is stopped, and nitrogen is introduced for purging for 30 min, the catalyst is removed by filtration, and the hydrogenation product is measured by HPLC to obtain that the content of 3-(8, 11, 14-pentadecatrienyl)-phenol is equal to 0.2%, the obtained hydrogenation product is preheated to 170℃, small molecular organic matter is removed through a thin film evaporator with a vacuum degree of 100 Pa first, and then heating is carried out to 180℃, and the distillation product pentadecyl phenol is obtained through a short path evaporator with an adjusted vacuum degree of 4 Pa.

[0055] 60.2 kg of the distillation product is put into an alkoxylation reaction kettle, 559 g of 30% potassium methoxide methanol solution is added, heating is carried out to 90℃, vacuum dehydration is carried out for 60 min, the vacuum degree is -0.099 MPa, the water content is tested by sampling to be equal to 0.05%, after the dehydration is completed, nitrogen is used to replace the air in the kettle to make the oxygen content in the kettle less than 100 ppm, heating is carried out to 120℃, 104.4 kg of propylene oxide is continuously introduced, the reaction temperature is controlled to be 130℃ during the period, after the propylene oxide is completely introduced, the material temperature is maintained, and the reaction is continuously carried out for 180 min, the temperature is reduced to 100℃, vacuum degassing is carried out for 60 min, the vacuum degree is -0.099 MPa, after the vacuum is stopped, deionized water is added to adjust the pH value to 7, and pentadecyl phenol polyoxypropylene (9) ether is obtained.

[0056] 82.3 kg of pentadecyl phenol polyoxypropylene (9) ether is introduced into a falling film reactor, and a mixed gas of sulfur trioxide diluted with dry air with a volume concentration of 5% is introduced, wherein the dew point of the dry air is -40℃, so that the molar ratio of pentadecyl phenol polyoxypropylene (9) ether and sulfur trioxide is 1:1.15, and then a sulfation reaction is carried out, the sulfation product is continuously transferred to a neutralizer, 2.5% sodium hydroxide solution is continuously introduced for neutralization, the pH value is controlled to be 10.5, deionized water is added in proper amount to adjust the solid content of the product to 75%, and pentadecyl phenol alkoxyl ether sodium sulfate surfactant is obtained. Example 6

[0057] The difference between the embodiment and example 1 is that the Raney nickel catalyst accounts for 4% of the mass of the pretreated liquid. Example 7

[0058] The difference between this example and Example 1 is only that the Raney nickel catalyst is the modified Raney nickel catalyst prepared in Preparation Example 1. Example 8

[0059] The difference between this example and Example 2 is only that 60 kg of pentadecylphenol polyoxyethylene (4) ether and 72 kg of dodecyl / tetradecyl alcohol polyoxyethylene (2) ether are mixed and then fed into the falling film reactor. Example 9

[0060] The difference between this example and Example 2 is only that 42 kg of pentadecylphenol polyoxyethylene (4) ether and 90 kg of dodecyl / tetradecyl alcohol polyoxyethylene (2) ether are mixed and then fed into the falling film reactor.

[0061] Comparative Example 1

[0062] The difference between this example and Example 1 is only that the hydrogenated product is not purified by distillation, but is directly fed into the alkoxylation reactor.

[0063] The pentadecylphenol alkoxy ether sodium sulfate surfactants prepared in the examples and comparative examples are subjected to the following tests:

[0064] Test of active matter content: in accordance with GB / T-5173-2018;

[0065] Test of total solid content: drying at 120°C for 2 h;

[0066] Conversion rate: active matter content / total solid content;

[0067] Surface tension: Dataphysics DCAT 21 surface tension meter; results are shown in Table 1;

[0068] Example 1, Examples 6-7 are tested by HPLC for the hydrogenation purity of 3-(8-pentadecenyl)-phenol and 3-(8,11-pentadecadienyl)-phenol in the composition of the distillation product; results are shown in Table 2;

[0069] Table 1

[0070]

[0071] Table 2

[0072]

[0073] From the above table, it can be seen that the surfactant prepared by the above-mentioned embodiments has stable appearance performance, high solid content, high conversion rate, high efficiency of reducing surface tension, can prevent the product pentadecyl phenol alkoxyl ether sodium sulfate from solidifying at low temperature, blocking the production pipeline and causing accidents, and makes up for the shortcomings of poor biodegradability of existing surfactants, and meets the requirements of environmental protection. Among them, it can be seen from examples 1, 2 and 8-9 that compared with pentadecyl benzene long chain, the straight chain hydrophobic long chain of fatty alcohol can reduce the intermolecular force and improve the fluidity of the mixture, which is conducive to continuous neutralization to obtain a fully alkali neutralized product and improve the activity of the surfactant; the pentadecyl phenol polyoxyethylene (4) ether and the dodecyl / tetradecyl alcohol polyoxyethylene (2) ether in the application have a hydrophobic long chain with a close chain length in the preferred ratio range, so that the hydrophobic segment realizes better arrangement, which is conducive to the reduction of surface tension. The chain length of C8-C14 ensures the hydrophobicity and is more conducive to the reasonable arrangement of the above-mentioned hydrophobic chain. As can be seen from comparative examples 1 and 6-7, by modifying the Raney nickel catalyst with molecular sieve, the double bond at position 14 enters the ZSM-5 molecular sieve channel for high selectivity hydrogenation, which improves the concentration of the target product and makes the final product have good fluidity at low temperature, ensuring the continuity of production.

[0074] The above are preferred embodiments of the application, and do not limit the protection scope of the application, therefore: any equivalent changes made on the structure, shape and principle of the application should be covered within the protection scope of the application.

Claims

1. A process for the preparation of a sodium pentadecyl phenol alkoxyl ether sulfate surfactant characterized by: The method comprises the following steps: (1) cashew shell liquid pretreatment: the decarboxylation cashew shell liquid is treated by inorganic acid solution, filtered and centrifuged to obtain a pretreated liquid; (2) selective hydrogenation: a metal-based catalyst is added to the pretreated liquid, heated to 80-100 DEG C under nitrogen atmosphere, hydrogen is introduced, the pressure is controlled to be less than 1.2 MPa, and the hydrogenation is continued until the content of 3-(8, 11, 14-pentadecatrienyl) phenol is less than or equal to 0.5%; (3) distillation purification: the hydrogenation product is removed by an evaporator under vacuum; high-purity pentadecyl phenol is obtained by vacuum distillation; (4) alkoxylation: an alkaline catalyst is added to the high-purity pentadecyl phenol, 1, 2-alkylene oxide is introduced under nitrogen atmosphere to carry out alkoxylation reaction, vacuum degassing is carried out after the reaction, and the temperature is lowered; (5) sulfation and continuous neutralization: the product of (4) is introduced into a falling film reactor, sulfur trioxide mixed gas is introduced to carry out sulfation reaction, the sulfated product is continuously transferred to a neutralizer to adjust the pH to 8.0-11.5, and the product is obtained by vacuum degassing again. The metal-based catalyst accounts for 0.2-2.0% of the mass of the pretreated liquid. The metal-based catalyst is a modified Raney nickel catalyst, and the preparation method comprises the following steps: ZSM-5 molecular sieve and Raney nickel powder are mixed, water balls are added for ball milling to form a uniform slurry, the slurry is dried, calcined at 450-500 DEG C for 1-2 h, a composite catalyst is obtained, an aqueous solution containing H2PtCl6 is added dropwise to the composite catalyst, ultrasonic treatment is carried out for 15 min, ZnO powder is added, stirring is carried out for 30-45 min to uniformly disperse the ZnO powder, N2 atmosphere calcination is carried out at 400-450 DEG C for 1-2 h, and a modified Raney nickel catalyst is obtained. In the step (5), the product of (4) and C8-C14 fatty alcohol polyoxyethylene ether or fatty alcohol alkoxyl ether are mixed, and then introduced into a falling film reactor.

2. A process for the preparation of sodium pentadecyl phenol alkoxyl ether sulphate surfactant according to claim 1, characterized in that: In the step (3), the vacuum distillation conditions are as follows: the temperature is 180-190 DEG C, and the absolute vacuum degree is 4-10 Pa.

3. The method for preparing a sodium pentadecylphenol alkoxyether sulfate surfactant according to claim 1, characterized in that: In the step (4), the vacuum degassing conditions are as follows: the vacuum degree is-0.096~-0.099 MPa, and the degassing time is 45-60 min.

4. The method for preparing a sodium pentadecylphenol alkoxyether sulfate surfactant according to claim 1, characterized in that: In the step (5), the sulfur trioxide mixed gas is a mixed gas with a sulfur trioxide volume concentration of 3-8% diluted by dry air.

5. The method for preparing a sodium pentadecylphenol alkoxyether sulfate surfactant according to claim 1, characterized in that: In the step (5), the molar ratio of the product of (4) to sulfur trioxide is 1:(1.03-1.2).

6. The method for preparing a sodium pentadecylphenol alkoxyether sulfate surfactant according to claim 1, characterized in that: The C8-C14 fatty alcohol polyoxyethylene ether comprises one or more of the following: n-octanol polyoxyethylene ether, iso-octanol polyoxyethylene ether, n-decanol polyoxyethylene ether, iso-decanol polyoxyethylene ether, dodecyl / tetradecyl alcohol polyoxyethylene ether, isododecanol polyoxyethylene ether and isotridecanol polyoxyethylene ether; and the fatty alcohol alkoxyl ether comprises one or more of the following: n-octanol alkoxyl ether, iso-octanol alkoxyl ether, n-decanol alkoxyl ether, iso-decanol alkoxyl ether, dodecyl / tetradecyl alcohol alkoxyl ether, isododecanol alkoxyl ether and isotridecanol alkoxyl ether.

Images