Method for preparing secondary alcohol surfactant

Abstract

To provide a method for preparing a secondary alcohol surfactant that does not affect on color and aroma of a final product by remarkably improving a fluid point, a gel region and emulsifying force.SOLUTION: Secondary alcohol surfactants are obtained by adding secondary alcohols containing 0.5%-5% of bivalent alcohol to epoxide compounds and through a two-step process. Secondary alcohols that serve as raw materials with 0.5%-5% bivalent alcohol are produced by adding normal paraffins and boron compounds to a reactor for oxidation reactions. After the reaction is completed, separation is performed by flash evaporation, after the alkaline treatment, entering into the distillation process. Finally, secondary alcohols containing 0.5%-5% bivalent alcohol are obtained from the top of the column after distillation.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for preparing surfactants, and in particular to a method for preparing secondary alcohol surfactants. [Background technology]

[0002] Secondary alcohol nonionic surfactants (Secondary Alcohol Ethoxylate) are particularly 8-16 Liquid normal paraffin (C 12-14 A mixture of homologues with three or fewer carbon atoms in succession, hereinafter referred to as liquid normal paraffin or normal paraffin, is obtained by catalytic oxidation. 8-16 Secondary alcohol (C 12-14 This refers to the product obtained by adding epoxyethane (or epoxypropane and / or epoxybutane) to a mixture of three or fewer consecutive homologues with three or fewer carbon atoms, hereafter referred to as dihydric alcohols, in two steps.

[0003] In the conventional manufacturing process of secondary alcohol surfactants, dihydric alcohols are considered impurities that have a negative impact on the color and odor of the final product, and are therefore removed by a dehydrogenation rectification process. To address these issues, it would be meaningful to consider secondary alcohols containing trace amounts of dihydric alcohols that do not significantly affect the color and odor of the final product in order to improve the process. Summary of the Invention [Problem to be solved by the invention]

[0004] The technical problem to be solved by the present invention is to provide a secondary alcohol surfactant and its preparation method and composition, in which the secondary alcohol contains 0.5%-5% dihydric alcohol and has the properties of significantly improving the pour point, gel range and emulsifying power of the final nonionic surfactant composition. [Means for solving the problem]

[0005] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0006] The present invention provides a method for preparing a secondary alcohol surfactant, which is obtained by adding a secondary alcohol, the dihydric alcohol content of which is 0.5%-5%, to an epoxy compound through a two-step process. Here, the molecular formula of the secondary alcohol is as follows: [ka] Of which, a+b=5-13, a≧0, b≧0 Here, the molecular formula of the dihydric alcohol is as follows: [ka] Of these, a+b+C=6~14, a≧1, b≧0, C≧1 The epoxy compound is one or more of epoxyethane, epoxypropane, and epoxybutane mixed in an arbitrary ratio of 2.

[0007] In the method for producing the secondary alcohol surfactant according to the present invention, a more preferred technical solution is that the raw secondary alcohol containing 0.5%-5% dihydric alcohol is obtained by the following method:

[0008] Normal paraffin and boron compound are added to the reactor to carry out the oxidation reaction. After the reaction is complete, they are separated by flash evaporation and treated with alkali before entering the rectification process. During the rectification process, the reboiler steam consumption and the overhead reflux ratio are controlled to 0.2-3, the bottom temperature is 180-200°C, the top temperature is 90-120°C, and the furnace pressure is 1-10mmHg. After rectification, the secondary alcohol product is taken out from the top of the column, and the dihydric alcohol content in the secondary alcohol product is 0.5%-5%.

[0009] The boron compound is a mixture of one or more of boric acid, metaboric acid, and boron oxide in any ratio, and the normal paraffin has a carbon atom number of C 12-14 It is a mixture of saturated aliphatic hydrocarbons in which

[0010] In the method for preparing the secondary alcohol surfactant according to the present invention, the secondary alcohol raw material containing 0.5%-5% dihydric alcohol can be obtained by the following method:

[0011] Normal paraffin and boron compound in a weight ratio of 1000:70-80 were added to a reactor equipped with an orifice plate distributor, and a mixed gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 95 vol% was blown in at 25 L / h, followed by a reaction at atmospheric pressure and 175°C for 2 hours.

[0012] The resulting oxidation reaction mixture was flash evaporated at 0.6 KPa (A) and 170°C to remove unreacted saturated aliphatic hydrocarbons. Water was then added to the liquid phase in the furnace and hydrolyzed at 90°C to separate an oil phase containing alcohol and small amounts of organic acids and organic esters. The resulting oil layer was saponified and washed with water to remove the organic acids and organic esters. 5 wt.% NaOH was added to the resulting oil phase for alkali treatment. The mixture was stirred at 100°C for 1 hour, cooled, and then transferred to a rectification vessel for rectification. The pressure at the top of the vessel was controlled at 0.6 KPa (A), the pressure in the furnace at 1.3 KPa (A), the extraction temperature at the top of the vessel at 90-120°C, and the reflux ratio at the top of the vessel at 0.2-3. The secondary alcohol with a dihydric alcohol content of 0.5%-5% was extracted as a distillate.

[0013] In the preparation method of the secondary alcohol surfactant according to the present invention, a more preferred technical solution is to prepare a secondary alcohol surfactant having a carbon atom number C 12-14 The mixture of saturated aliphatic hydrocarbons is 12 and C with a mass fraction of 40-60% 13 and C with a mass fraction of 20-35% 14 Contains:

[0014] In the preparation method of the secondary alcohol surfactant according to the present invention, a more preferred technical solution is that the carbon number C 12-14 The mixture of saturated aliphatic hydrocarbons is 12 and C with a mass fraction of 40-60% 13 and C with a mass fraction of 20-30% 14 Contains:

[0015] In the preparation method of the secondary alcohol surfactant according to the present invention, a more preferred technical solution is that the carbon number C 12-14 The mixture of saturated aliphatic hydrocarbons is 12 and C with a mass fraction of 45-55% 13 and C with a mass fraction of 23-28% 14 Contains:

[0016] In the method for preparing secondary alcohol surfactants according to the present invention, a more preferred technical solution is that the rectification is continuous rectification or intermittent rectification, and the rectification column is a packed column or a plate column.

[0017] In the preparation method of secondary alcohol surfactant according to the present invention, a more preferred technical solution is that the two-step addition method includes the following steps:

[0018] Step S1: secondary alcohol containing 0.5%-5% dihydric alcohol as raw material is added with catalyst BF3 and epoxy compound to produce alkoxylated product with average addition number of 0.5-2.5 moles, and after catalytic removal and rectification process, an alkoxylated intermediate product with average addition number of 1-3.5 moles without free alcohol is produced. During the rectification process, the monohydric alcohol content of the secondary alcohol taken out from the top of the tower is 60%-90%, and the free secondary alcohol content in the alkoxylated intermediate product taken out from the tower furnace is 0-1%. According to the amount of steam used in the reboiler and the reflux ratio of the tower, the reflux ratio of the tower is controlled to 0.2-3, the temperature of the tower furnace is 180-200°C, the temperature of the tower top is 90-120°C, and the pressure is 1-10mmHg.

[0019] Step s2: The alkoxylated intermediate product obtained in step s1 is added to an epoxy compound in the presence of an aqueous sodium or potassium hydroxide solution with an alkaline catalyst mass concentration of 40% to produce a secondary alcohol surfactant.

[0020] In the preparation method of secondary alcohol surfactant according to the present invention, a more preferred technical solution is that the two-step addition method includes the following steps:

[0021] Step s1: The raw secondary alcohol containing 0.5%-5% dihydric alcohol is introduced into an autoclave equipped with a stirrer and temperature controller, and catalyst BF3 is added. Under the initial nitrogen pressure of 0.05 MPa and temperature of 50°C, epoxyethane or epoxypropane or epoxybutane is introduced at a constant rate, with the weight ratio of the raw secondary alcohol to the epoxy compound being 1000:310-350, and the amount of catalyst BF3 added is 3‰ of the secondary alcohol.

[0022] After the reaction is complete, a neutralization reaction is carried out with a 0.5% NaOH aqueous solution at 90°C, followed by washing with water until the pH reaches 7. The oil phase is then rectified at 0.6 kPaA until the temperature of the tower furnace reaches 180-200°C, yielding an ethoxylate addition product with an average addition number of 3 moles of epoxy compound.

[0023] Step s2: The obtained ethoxylate adduct is put into an autoclave, NaOH is added, and under the initial nitrogen pressure of 0.05 MPa and the temperature of 150°C, epoxyethane or epoxypropane or epoxybutane is introduced at a constant rate, the weight ratio of the epoxy compound added in step s2 to the secondary alcohol added in step s1 is 390-410:1000, and after the reaction, the surfactant is neutralized with acetic acid to form an epoxyethane adduct, and the average mole number of the epoxy compound added is confirmed to be 9.0 by the hydroxyl value measurement method.

[0024] In the method of the present invention, a dihydric alcohol ether is introduced into a secondary alcohol surfactant, and the dihydric alcohol ether has the same average number of epoxy compounds added as the secondary alcohol surfactant. Here, the molecular formula of the dihydric alcohol ether is as follows: [ka] wherein R and R' represent an alkylene group having 2 to 4 carbon atoms, a+b+C=6 to 14, a≧1, b≧0, C≧1, and x+y=1 to 50. The reaction formula for dihydric alcohol ether is as follows: [ka] [Effects of the Invention]

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] The present invention helps to significantly improve the pour point, gel range and emulsifying power of the final nonionic surfactant product by introducing a dihydric alcohol as a raw material, accounting for 0.5-5% of the total secondary alcohol, without affecting the color and odor of the final product.

[0027] The present invention controls the content of dihydric alcohol in the secondary alcohol product by changing the amount of steam used in the reboiler and the amount of reflux from the top of the dehydrogenation rectification column, and by controlling the temperature at the top of the column to 90-120°C and the pressure to 1-10 mmHg.

[0028] The present invention involves adding raw materials to a secondary alcohol surfactant to produce a dihydric alcohol ether, in which the dihydric alcohol ether has the same average number of epoxyethane (or epoxypropane and / or epoxybutane) additions as the secondary alcohol surfactant composition. Secondary alcohol nonionic surfactant products containing dihydric alcohol ether have advantages such as a low pour point, strong fluidity, and a narrow gel region. The gelling properties and emulsifying properties of the product are improved, without affecting the color or odor of the final product. DETAILED DESCRIPTION OF THE INVENTION

[0029] The present invention will now be described in more detail with reference to specific examples.

[0030] Example 1: Preparation method of secondary alcohol surfactant, the steps of which are as follows:

[0031] Step s1: Oxidation reaction 1000 g of normal paraffin and 75 g of a boron compound are placed in a reactor equipped with an orifice plate distributor, and a mixed gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 95 vol% is blown in at 25 L / h, followed by reaction at atmospheric pressure and 175°C for 2 hours.

[0032] This oxidation reaction mixture is flash evaporated at 0.6 KPa (A) and 170°C to remove unreacted saturated aliphatic hydrocarbons, and then 400 g of water is added to the liquid phase in the tower furnace and hydrolysis is carried out at 90°C to separate an oil phase containing alcohol and small amounts of organic acids and organic esters. The resulting oil layer is saponified and washed with water to remove the organic acids and organic esters.

[0033] 5 wt.% of NaOH is added to this oil phase and stirred at 100°C for 1 hour. After cooling, the mixture is transferred to a rectification vessel for rectification. The pressure at the top of the column is controlled to 0.6 KPa (A), the pressure in the column furnace to 1.3 KPa (A), the extraction temperature at the top of the column to 90-120°C, and the reflux ratio at the top of the column to 0.2-3. The secondary alcohol with a dihydric alcohol content of 0.5%-5% is extracted as a distillate fraction.

[0034] Step s2: Two-stage additive process 1 kg of the secondary alcohol mixture obtained in step s1 is placed in a 2 L autoclave equipped with a stirrer, a temperature controller, and an inlet tube for introducing an epoxy compound. 3 g of BF3·Et catalyst is added, and 330 g of epoxyethane is introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 50°C.

[0035] After the reaction is complete, a neutralization reaction is carried out with a 0.5% aqueous solution of NaOH at 90°C, and the mixture is washed with water until the pH reaches 7. The oil phase is rectified at 0.6 kPaA until the temperature of the tower furnace reaches 180-200°C, yielding an ethoxylate addition product with an average addition number of 3 moles of epoxy compound.

[0036] Next, 500 g of the obtained ethoxylate adduct and 2 g of NaOH are placed in the same autoclave as above, and 398 g of epoxyethane is introduced at a constant rate under conditions of an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C. After the reaction, the surfactant is neutralized with acetic acid to form an epoxyethane adduct, and the average number of moles of the epoxy compound added is confirmed to be 9.0 by hydroxyl value measurement.

[0037] Example 2, Comparative Experiment The gelling temperature and emulsification performance of secondary alcohol surfactants are examined in the following examples and comparative examples. The following examples are experiments using the method of the present invention, while the comparative examples are experiments using the conventional technology.

[0038] (Experimental Example 1) Preparation method of secondary alcohol surfactant Experiment 1:

[0039] (1) Oxidation process Number of carbon atoms C 12-14 1000g of saturated aliphatic hydrocarbon mixture (C with a mass fraction of 15%) 12 , with a mass fraction of 60% C 13 , with a mass fraction of 25% C 14) and 75 g of metaboric acid were added to a reactor equipped with an orifice plate distributor, and a gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 95 vol% was blown in at 25 L / h, followed by reaction at atmospheric pressure and 175°C for 2 hours.

[0040] The oxidation reaction mixture was flash evaporated at 0.6 KPa(A) and 170°C to remove unreacted saturated aliphatic hydrocarbons. 400 g of water was added to the liquid phase in the column and hydrolyzed at 90°C. An oil phase containing alcohol and small amounts of organic acids and organic esters was separated. The resulting oil phase was saponified and washed with water to remove the organic acids and organic esters. 5 wt.% NaOH was added to the oil phase and stirred at 100°C for 1 hour. After cooling, the oil was transferred to a rectification vessel for rectification. The column top pressure was 0.6 KPa(A), the column top pressure was 1.3 KPa(A), the column top temperature was 90-120°C, and the column top reflux ratio was 1:3. The distillate fraction was primarily secondary alcohols, of which 0.5% was dihydric alcohols and contained trace amounts of carbonyl compounds. The resulting secondary alcohol mixture was used as the epoxyethane feedstock, and its composition is shown in Table 1.

[0041] (2) Epoxyethane addition process 1 kg of the secondary alcohol mixture was placed in a 2 L autoclave equipped with a stirrer, temperature control, and an inlet tube for introducing epoxyethane (EO). 3 g of BF3 catalyst was added, and 330 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 50°C. After the reaction was complete, a neutralization reaction was carried out with a 0.5% aqueous solution of NaOH at 90°C, followed by water washing until the pH reached 7. The oil phase was rectified at 0.6 kPa until the temperature of the column reached 180-200°C, yielding an ethoxylate adduct with an average number of EO adducts of 3 moles. Next, 500 g of the resulting ethoxylate adduct and 2 g of NaOH were placed in the same autoclave as above, and 398 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C. After the reaction, the mixture was neutralized with acetic acid to yield the resulting surfactant epoxyethane adduct. The average number of EO adducts was confirmed to be 9.0 by hydroxyl value measurement.

[0042] (Experimental Example 2) Experiment 2: Preparation of secondary alcohol surfactants

[0043] (1) Oxidation process Number of carbon atoms C 12-14 1000g of saturated aliphatic hydrocarbon mixture (C with a mass fraction of 30%) 12 , with a mass fraction of 40% C 13 , with a mass fraction of 30% C 14 ) and 75 g of metaboric acid were added to a reactor equipped with an orifice plate distributor, and a gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 95 vol% was blown in at 25 L / h, followed by reaction at atmospheric pressure and 175°C for 2 hours.

[0044] The oxidation reaction mixture was flash evaporated at 0.6 KPa(A) and 170°C to remove unreacted saturated aliphatic hydrocarbons. 400 g of water was added to the liquid phase in the column and hydrolyzed at 90°C. An oil phase containing alcohol and small amounts of organic acids and organic esters was separated. The resulting oil phase was saponified and washed with water to remove the organic acids and esters. 5 wt.% NaOH was added to the oil phase and stirred at 100°C for 1 hour. After cooling, the oil was transferred to a rectification vessel for rectification. The column top pressure was 0.6 KPa(A), the column top pressure was 1.3 KPa(A), the column top temperature was 90-104°C, and the column top reflux ratio was 0.2-3. The distillate fraction was primarily secondary alcohols, with a dihydric alcohol content of 1% and traces of carbonyl compounds. The resulting secondary alcohol mixture was used as the epoxyethane feedstock, and its composition is shown in Table 1.

[0045] (2) Epoxyethane addition process 1 kg of the secondary alcohol mixture was placed in a 2 L autoclave equipped with a stirrer, temperature control, and an inlet tube for introducing epoxyethane (EO). 3 g of BF3 catalyst was added, and 330 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 50°C. After the reaction was completed, a neutralization reaction was carried out with a 0.5% aqueous NaOH solution at 90°C, followed by water washing until the pH reached 7. The oil phase was rectified at 0.6 kPa (A) until the temperature of the column reached 180-200°C, yielding an ethoxylate adduct with an average number of EO moles added of 3. Next, 500 g of the resulting ethoxylate adduct and 2 g of NaOH were placed in the same autoclave as above, and 398 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C. After the reaction, the surfactant was neutralized with acetic acid to yield the epoxyethane adduct. The average number of moles of EO added is confirmed to be 9.0 by hydroxyl value measurement.

[0046] (Experimental Example 3) Experiment 3: Preparation of secondary alcohol surfactants

[0047] (1) Oxidation process Number of carbon atoms C 12-14 1000g of saturated aliphatic hydrocarbon mixture (C with a mass fraction of 20%) 12 , with a mass fraction of 50% C 13 , with a mass fraction of 30% C 14 ) and 75 g of metaboric acid were added to a reactor equipped with an orifice plate distributor, and a gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 95 vol% was blown in at 25 L / h, followed by reaction at atmospheric pressure and 175°C for 2 hours.

[0048] The oxidation reaction mixture was flash evaporated at 0.6 KPa(A) and 170°C to remove unreacted saturated aliphatic hydrocarbons. 400 g of water was added to the liquid phase in the column and hydrolyzed at 90°C. An oil phase containing alcohol and small amounts of organic acids and organic esters was separated. The resulting oil phase was saponified and washed with water to remove the organic acids and organic esters. 5 wt.% NaOH was added to the oil phase and stirred at 100°C for 1 hour. After cooling, the oil was transferred to a rectification vessel for rectification. The column top pressure was 0.6 KPa(A), the column pressure was 1.3 KPa(A), the column top temperature was 90-110°C, and the column top reflux ratio was 0.2-3. The distillate fraction was primarily secondary alcohols, of which 2% was dihydric alcohol and contained traces of carbonyl compounds. The resulting secondary alcohol mixture was used as the epoxyethane feedstock; its composition is shown in Table 1.

[0049] (2) Epoxyethane addition process 1 kg of the secondary alcohol mixture was placed in a 2 L autoclave equipped with a stirrer, temperature control, and an inlet tube for introducing epoxyethane (EO). 3 g of BF3 catalyst was added, and 330 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 50°C. After the reaction was completed, a neutralization reaction was carried out with a 0.5% aqueous NaOH solution at 90°C, followed by water washing until the pH reached 7. The oil phase was rectified at 0.6 kPa (A) until the temperature of the column reached 180-200°C, yielding an ethoxylate adduct with an average number of EO moles added of 3. Next, 500 g of the resulting ethoxylate adduct and 2 g of NaOH were placed in the same autoclave as above, and 398 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C. After the reaction, the surfactant was neutralized with acetic acid to yield the epoxyethane adduct. The average number of moles of EO added is confirmed to be 9.0 by hydroxyl value measurement.

[0050] (Experimental Example 4) Experiment 4: Preparation of secondary alcohol surfactants

[0051] (1) Oxidation process Number of carbon atoms C 12-141000g of saturated aliphatic hydrocarbon mixture (C with a mass fraction of 30%) 12 , with a mass fraction of 50% C 13 , with a mass fraction of 20% C 14 ) and 75 g of metaboric acid were added to a reactor equipped with an orifice plate distributor, and a gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 95 vol% was blown in at 25 L / h, followed by reaction at atmospheric pressure and 175°C for 2 hours.

[0052] The oxidation reaction mixture was flash evaporated at 0.6 KPa(A) and 170°C to remove unreacted saturated aliphatic hydrocarbons. 400 g of water was added to the liquid phase in the column and hydrolyzed at 90°C. An oil phase containing alcohol and small amounts of organic acids and organic esters was separated. The resulting oil layer was saponified and washed with water to remove the organic acids and esters. 5 wt.% NaOH was added to the oil phase and stirred at 100°C for 1 hour. After cooling, the oil was transferred to a rectification vessel for rectification. The column top pressure was 0.6 KPa(A), the column pressure was 1.3 KPa(A), the column top temperature was 90-115°C, and the column top reflux ratio was 0.2-3. The distillate fraction was primarily secondary alcohols, of which 3% was dihydric alcohol and contained trace amounts of carbonyl compounds. The resulting secondary alcohol mixture was used as the epoxyethane feedstock; its composition is shown in Table 1.

[0053] (2) Epoxyethane addition process 1 kg of the secondary alcohol mixture was placed in a 2 L autoclave equipped with a stirrer, temperature control, and an inlet tube for introducing epoxyethane (EO). 3 g of BF3 catalyst was added, and 330 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 50°C. After the reaction was completed, a neutralization reaction was carried out with a 0.5% aqueous NaOH solution at 90°C, followed by water washing until the pH reached 7. The oil phase was rectified at 0.6 kPa (A) until the temperature of the column reached 180-200°C, yielding an ethoxylate adduct with an average number of EO moles added of 3. Next, 500 g of the resulting ethoxylate adduct and 2 g of NaOH were placed in the same autoclave as above, and 398 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C. After the reaction, the surfactant was neutralized with acetic acid to yield the epoxyethane adduct. The average number of moles of EO added is confirmed to be 9.0 by hydroxyl value measurement.

[0054] (Experimental Example 5) Experiment 5: Preparation of secondary alcohol surfactant

[0055] (1) Oxidation process Number of carbon atoms C 12-14 1000g of saturated aliphatic hydrocarbon mixture (C with a mass fraction of 22%) 12 , with a mass fraction of 50% C 13 , with a mass fraction of 28% C 14 ) and 75 g of metaboric acid were added to a reactor equipped with an orifice plate distributor, and a gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 94 vol% was blown in at 25 L / h, followed by reaction at atmospheric pressure and 175°C for 2 hours.

[0056] The oxidation reaction mixture was flash evaporated at 0.6 KPa(A) and 170°C to remove unreacted saturated aliphatic hydrocarbons. 400 g of water was added to the liquid phase in the column and hydrolyzed at 90°C. An oil phase containing alcohol and small amounts of organic acids and organic esters was separated. The resulting oil phase was saponified and washed with water to remove the organic acids and organic esters. 5 wt.% NaOH was added to the oil phase and stirred at 100°C for 1 hour. After cooling, the oil was transferred to a rectification vessel for rectification. The overhead pressure was 0.6 KPa(A), the bottom pressure was 1.3 KPa(A), the overhead extraction temperature was 90-118°C, and the overhead reflux ratio was 0.2-3. The distillate fraction was primarily secondary alcohols, of which 4% was dihydric alcohol and contained traces of carbonyl compounds. The resulting secondary alcohol mixture was used as the epoxyethane feedstock; its composition is shown in Table 1.

[0057] (2) Epoxyethane addition process 1 kg of the secondary alcohol mixture was placed in a 2 L autoclave equipped with a stirrer, temperature control, and an inlet tube for introducing epoxyethane (EO). 3 g of BF3 catalyst was added, and 330 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 50°C. After the reaction was completed, a neutralization reaction was carried out with a 0.5% aqueous solution of NaOH at 90°C, followed by water washing until the pH reached 7. The oil phase was rectified at 0.6 kPa (A) until the temperature of the column reached 180-200°C, yielding an ethoxylate adduct with an average number of EO moles. Next, 500 g of the resulting ethoxylate adduct and 2 g of NaOH were placed in the same autoclave as above, and 398 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C. After the reaction, the surfactant was neutralized with acetic acid to yield the epoxyethane adduct. The average number of moles of EO added is confirmed to be 9.0 by hydroxyl value measurement.

[0058] (Experimental Example 6) Experiment 6: Preparation of secondary alcohol surfactants

[0059] (1) Oxidation process Number of carbon atoms C 12-141000g of saturated aliphatic hydrocarbon mixture (C with a mass fraction of 27%) 12 , with a mass fraction of 50% C 13 , with a mass fraction of 23% C 14 ) and 75 g of metaboric acid were added to a reactor equipped with an orifice plate distributor, and a gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 94 vol% was blown in at 25 L / h, followed by reaction at atmospheric pressure and 175°C for 2 hours.

[0060] The oxidation reaction mixture was flash evaporated at 0.6 KPa(A) and 170°C to remove unreacted saturated aliphatic hydrocarbons. 400 g of water was added to the liquid phase in the column and hydrolyzed at 90°C. An oil phase containing alcohol and small amounts of organic acids and organic esters was separated. The resulting oil phase was saponified and washed with water to remove the organic acids and organic esters. 5 wt.% NaOH was added to the oil phase and stirred at 100°C for 1 hour. After cooling, the oil was transferred to a rectification vessel for rectification. The column top pressure was 0.6 KPa(A), the column top pressure was 1.3 KPa(A), the column top temperature was 90-120°C, and the column top reflux ratio was 0.2-3. The distillate fraction was primarily secondary alcohols, of which 5% was dihydric alcohol and contained traces of carbonyl compounds. The resulting secondary alcohol mixture was used as the epoxyethane feedstock; its composition is shown in Table 1.

[0061] (2) Epoxyethane addition process 1 kg of the secondary alcohol mixture was placed in a 2 L autoclave equipped with a stirrer, temperature control, and an inlet tube for introducing epoxyethane (EO). 3 g of BF3 catalyst was added, and 330 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 50°C. After the reaction was completed, a neutralization reaction was carried out with a 0.5% aqueous solution of NaOH at 90°C, followed by water washing until the pH reached 7. The oil phase was rectified at 0.6 kPa (A) until the temperature of the column reached 180-200°C, yielding an ethoxylate adduct with an average number of EO moles. Next, 500 g of the resulting ethoxylate adduct and 2 g of NaOH were placed in the same autoclave as above, and 398 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C. After the reaction, the surfactant was neutralized with acetic acid to yield the epoxyethane adduct. The average number of moles of EO added is confirmed to be 9.0 by hydroxyl value measurement.

[0062] (Comparative Example 1) Comparative experiment 1 on the production methods of secondary alcohol surfactants.

[0063] (1) Oxidation process The number of carbon atoms is C 12 :C 13 :C 14 1000 g of a mixture of saturated aliphatic hydrocarbons with a ratio of 1:2:1 and 75 g of metaboric acid are added to a reactor equipped with an orifice plate distributor, and gas with an oxygen concentration of 5 vol% and a nitrogen concentration of 95 vol% is blown in at 25 L / h, followed by a reaction at atmospheric pressure and 175°C for 2 hours.

[0064] The oxidation reaction mixture was flash evaporated at 0.6 KPa(A) and 170°C to remove unreacted saturated aliphatic hydrocarbons. 400 g of water was added to the liquid phase in the column and hydrolyzed at 90°C to separate an oil phase containing alcohol and small amounts of organic acids and organic esters. The resulting oil phase was saponified and washed with water to remove the organic acids and organic esters. 5 wt.% NaOH was added to the oil phase and stirred at 100°C for 1 hour. After cooling, the oil phase was transferred to a rectification vessel for rectification. The column top pressure was controlled at 0.6 KPa(A), the column top pressure at 1.3 KPa(A), the column top temperature at 90-98°C, and the column top reflux ratio at 0.2-3. The distillate fraction was primarily secondary alcohols, with zero dihydric alcohol content and traces of carbonyl compounds. The resulting secondary alcohol mixture was used as the epoxyethane feedstock; its composition is shown in Table 1.

[0065] (2) Epoxyethane addition process 1 kg of the secondary alcohol mixture was placed in a 2 L autoclave equipped with a stirrer, temperature control, and an inlet tube for introducing epoxyethane (EO). 3 g of BF3 catalyst was added, and 330 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 50°C. After the reaction was completed, a neutralization reaction was carried out with a 0.5% aqueous NaOH solution at 90°C, followed by water washing until the pH reached 7. The oil phase was rectified at 0.6 kPaA until the temperature of the column reached 180-200°C, yielding an ethoxylate adduct with an average EO addition of 3 moles. Next, 500 g of the resulting ethoxylate adduct and 2 g of NaOH were placed in the same autoclave as above, and 398 g of epoxyethane was introduced at a constant rate under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C. After the reaction, the surfactant was neutralized with acetic acid to yield the epoxyethane adduct. The average number of moles of epoxy compound (EO) added is confirmed to be 9.0 by hydroxyl value measurement.

[0066] In the above experiments, Experimental Examples 2-6 were operated in the same manner as Experimental Example 1, except that the temperature range of the top of the column from which the secondary alcohol mixture was taken out and the reflux ratio at the top of the column were changed compared to Example 1, and a secondary alcohol surfactant with an average added mole number of the epoxy compound EO of 9.0 was obtained. In Comparative Example 1, the distillation fraction was mainly secondary alcohol, and the content of dihydric alcohol in the secondary alcohol was 0. The rectification operation parameters and compositions of the secondary alcohol mixtures of Comparative Example 1 and Experimental Examples 1-6 are shown in Table 1.

[0067] [Table 1]

[0068] As can be seen from the gelling and emulsifying performance measurement results in Table 1, Comparative Example 1, and Experimental Examples 1-6, the emulsifying performance of secondary alcohols with dihydric alcohol contents of 0.5%-5% was 54.3-70.2, and the higher the dihydric alcohol content, the better the emulsifying and gelling performance. This confirms that the product of the present invention has advantages such as a low pour point, high fluidity, and a narrow gel region, and that the gelling performance and emulsifying ability of the product have been improved.

[0069] The relevant measurement methods in the examples are as follows.

[0070] 1. Gel performance measurement The gelling performance is expressed by the gelling temperature of an aqueous solution of a surfactant at a certain concentration, and is measured by the following method. Prepare an aqueous surfactant solution (25°C) with the specified concentration (30 wt% to 80 wt%) shown in Table 1 and heat it to 60°C. Next, place the sample in a water bath at 24°C ± 1.5°C and visually check for fluidity. If there is no fluidity, record the temperature. If there is fluidity even at 27°C, place the sample in a water bath at 14°C ± 1.5°C and record the temperature if there is no fluidity.

[0071] 2. Emulsification performance measurement The emulsifying performance is expressed as the time required for the emulsion containing the surfactant to separate into two phases. The longer the time required, the better the emulsifying performance. The measurement method is as follows. A 5 g / L aqueous solution of the surfactant composition is prepared, and 35 ml of the surfactant aqueous solution and 35 ml of oil are weighed out in that order into glass bottles that can withstand pressure and temperature. The bottles are placed in a water (oil) bath at 25°C and preheated for 30 minutes. After magnetic stirring for 1 minute (stirring speed 1000 R / min), the bottle is allowed to stand, and the time it takes to separate 20 ml of the aqueous phase is measured.

[0072] The technical features of the above embodiments can be combined in any way, and for the sake of brevity, not all possible combinations of the technical features in the above embodiments are described, but as long as there is no contradiction in the combinations of these technical features, they are all deemed to be within the scope described in this specification.

[0073] The above examples only describe some embodiments of the present invention, and although the descriptions are relatively specific and detailed, they should not be understood as limiting the scope of the invention patent. Those skilled in the art can make some modifications and improvements without departing from the concept of the present invention, all of which are within the scope of the present invention. Therefore, the patent protection scope of the present invention shall be governed by the appended claims.

Claims

1. 1. A method for preparing a secondary alcohol surfactant, comprising: The secondary alcohol surfactant is obtained by adding a secondary alcohol having a dihydric alcohol content of 0.5%-5% to a boron compound in a two-step process; wherein the molecular formula of the secondary alcohol is: 【Chemical 1】 Of which, a+b=5-13, a≧0, b≧0 wherein the molecular formula of the dihydric alcohol is as follows: 【Chemistry 2】 Of which, a + b + C = 6 to 14, a ≥ 1, b ≥ 0, C ≥ 1 the epoxy compound is one or more of epoxyethane, epoxypropane, and epoxybutane mixed in any ratio;

2. The secondary alcohol raw material containing 0.5%-5% dihydric alcohol is obtained by the following method: Normal paraffin and a boron compound are added to a reactor to carry out an oxidation reaction, and after completion of the reaction, they are separated by flash evaporation and then treated with alkali, followed by a rectification process. In the rectification process, the amount of steam used in the reboiler and the reflux ratio at the top of the column are controlled to be 0.2-3, the temperature at the bottom of the column is 180-200°C, the temperature at the top of the column is 90-120°C, and the pressure in the column furnace is 1-10 mmHg. After rectification, a secondary alcohol product is taken out from the top of the column, and the dihydric alcohol content in the secondary alcohol product is 0.5%-5%. The boron compound is a mixture of one or more of boric acid, metaboric acid, and boron oxide in any ratio, and the normal paraffin has a carbon atom number of C １２－１４ 2. A method for preparing the secondary alcohol surfactant of claim 1, wherein the secondary alcohol surfactant is a mixture of saturated aliphatic hydrocarbons,

3. The secondary alcohol raw material containing 0.5%-5% dihydric alcohol is obtained by the following method: Normal paraffin and a boron compound in a weight ratio of 1000:70-80 were added to a reactor equipped with an orifice plate distributor, and a mixed gas having an oxygen concentration of 5 vol% and a nitrogen concentration of 95 vol% was blown in at 25 L / h. The mixture was reacted at atmospheric pressure and 175°C for 2 hours. The method for preparing a secondary alcohol surfactant according to claim 1 or 2, wherein the resulting oxidation reaction mixture is subjected to flash evaporation at 0.6 KPa (A) and 170°C to remove unreacted saturated aliphatic hydrocarbons, water is added to the liquid phase in the kiln and hydrolysis is carried out at 90°C to separate an oil phase containing alcohol and small amounts of organic acids and organic esters, the resulting oil layer is saponified and washed with water to remove the organic acids and organic esters, 5 wt.% of NaOH is added to the resulting oil phase for alkali treatment, the mixture is stirred at 100°C for 1 hour, cooled, and then placed in a rectification vessel for rectification, the pressure at the top of the vessel is controlled to 0.6 KPa (A), the pressure in the kiln is controlled to 1.3 KPa (A), the extraction temperature at the top of the vessel is controlled to 90-120°C, and the reflux ratio at the top of the vessel is controlled to 0.2-3, and a secondary alcohol having a dihydric alcohol content of 0.5%-5% is extracted as a distillate fraction.

4. Number of carbon atoms C １２－１４ The mixture of saturated aliphatic hydrocarbons is １２ and C with a mass fraction of 40-60% １３ and C with a mass fraction of 20-35% １４ 3. A method for preparing the secondary alcohol surfactant of claim 2, comprising:

5. The number of carbon atoms C １２－１４ The mixture of saturated aliphatic hydrocarbons is １２ and C with a mass fraction of 40-60% １３ and a mass fraction of 20-30% C １４ 5. A method for preparing the secondary alcohol surfactant of claim 4, comprising:

6. The number of carbon atoms C １２－１４ The mixture of saturated aliphatic hydrocarbons is １２ and C with a mass fraction of 45-55% １３ and C with a mass fraction of 23-28% １４ 6. A method for preparing the secondary alcohol surfactant of claim 5, comprising:

7. 3. The method for preparing a secondary alcohol surfactant according to claim 2, wherein the rectification is continuous rectification or intermittent rectification, and the rectification column is a packed column or a plate column.

8. The two-step addition method includes the following steps: Step s1: A secondary alcohol containing 0.5%-5% dihydric alcohol is used as a raw material, and catalyst BF3 and an epoxy compound are added to produce an alkoxylated product with an average addition number of 0.5-2.5 moles. After catalytic removal and rectification, an alkoxylated intermediate product with an average addition number of 1-3.5 moles is produced, which does not contain free alcohol. During the rectification, the monohydric alcohol content of the secondary alcohol taken out from the top of the column is 60%-90%, and the free secondary alcohol content of the alkoxylated intermediate product taken out from the column furnace is 0-1%. The amount of steam used in the reboiler and the column furnace reflux ratio are controlled to make the column furnace reflux ratio 0.2-3, the column furnace temperature is 180-200°C, the column furnace temperature is 90-120°C, and the pressure is 1-10 mmHg.

3. The method for preparing a secondary alcohol surfactant according to claim 1 or 2, wherein step s2 is adding the alkoxylated intermediate product obtained in step s1 to an epoxy compound in the presence of a catalyst of an aqueous sodium or potassium hydroxide solution having an alkaline catalyst mass concentration of 40% to produce a secondary alcohol surfactant.

9. The two-step addition method includes the following steps: Step s1: A secondary alcohol containing 0.5%-5% dihydric alcohol is introduced into an autoclave equipped with a stirrer and a temperature controller, and catalyst BF3 is added. Under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C, epoxyethane or epoxypropane or epoxybutane is introduced at a constant rate, the mass ratio of the secondary alcohol to the epoxy compound is 1000:310-350, and the amount of catalyst BF3 added is 3% of the secondary alcohol; After the reaction is completed, a neutralization reaction is carried out with a 0.5% NaOH aqueous solution at 90°C, followed by washing with water until the pH reaches 7. The oil phase is then rectified at 0.6 kPaA until the temperature at the bottom of the column reaches 180-200°C, thereby obtaining an ethoxylate addition product having an average addition number of 3 moles of epoxy compound. Step s2: The obtained ethoxylate adduct is charged into an autoclave, NaOH is added, and under an initial nitrogen pressure of 0.05 MPa and a temperature of 150°C, epoxyethane, epoxypropane, or epoxybutane is introduced at a constant rate, the mass ratio of the epoxy compound charged in step s2 to the secondary alcohol charged in step s1 is 390-410:1000, and after the reaction, the surfactant is neutralized with acetic acid to obtain an epoxyethane adduct, and the average mole number of the epoxy compound added is confirmed to be 9.0 by a hydroxyl value measurement method.

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