A preparation process of ethylene bisstearic acid amide

Abstract

The present invention belongs to the synthesis technology of ethylene bis stearic acid amide, and relates to an efficient production process of ethylene bis stearic acid amide. The ethylene bis stearic acid amide is prepared by mixing stearic acid with ethylenediamine, and then adding a composite catalyst and an antioxidant; wherein the composite catalyst is a mixture of a supported solid of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate and zinc oxide, and the carrier of the supported solid is chromatographic silica gel and activated alumina, zinc oxide does not participate in the supporting process, and the antioxidant is sodium borohydride or sodium bisulfate. The composite catalyst used in the present invention is low in price, has a good catalytic effect, is free of impurities, and greatly shortens the time of the salt-forming stage and the dehydration time when synthesizing ethylene bis stearic acid amide, thereby improving the color and purity of ethylene bis stearic acid amide.

Description

Technical Field

[0001] The invention belongs to the synthesis technology of ethylene bisstearic acid amide and relates to a high-efficiency production process of ethylene bisstearic acid amide. Background Art

[0002] Ethylene bisstearamide is a multifunctional plastic additive, widely used in the production and processing of ABS resin, polyvinyl chloride, polypropylene, phenolic resin and amino resin. It can be used not only as internal and external lubricants, but also as anti-sticking agents, release agents, antistatic agents, viscosity regulators and surface brighteners.

[0003] The traditional process for producing ethylene bisstearamide is to directly react stearic acid with ethylenediamine. Although the process is simple, the reaction conditions are not harsh, and there is no waste, the product lacks color and has low purity, which is insufficient to support current industrial applications.

[0004] Therefore, how to develop a production process that can produce ethylene bisstearic acid amide with good color and high purity is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] In view of this, the present invention aims at the deficiencies in the prior art and provides a process for efficiently producing ethylene bisstearamide.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A preparation process of ethylene bisstearic acid amide, the process specifically comprising the following steps:

[0008] 1) Put stearic acid into a reaction kettle, heat it to 60°C-100°C, and melt it;

[0009] 2) After the stearic acid in step 1) is completely melted, the temperature is continued to be raised to 100° C.-120° C., nitrogen is introduced to replace the air in the reactor, and after adding the catalyst, ethylenediamine is gradually added dropwise into the reactor;

[0010] 3) After the addition of ethylenediamine in step 2) is completed, an antioxidant is added, the temperature is continued to be raised, and dehydration and drying is performed at 180° C.-200° C. for 1-3 hours to obtain the ethylene bisstearic acid amide.

[0011] 4) After the reaction is completed, the ethylene bisstearic acid amide is directly transported to a spray granulation tower through a conveying pipeline for granulation, and finally granular ethylene bisstearic acid amide is obtained.

[0012] Optionally, the molar ratio of the stearic acid to the ethylenediamine is 2:1.05-1.25, and the ethylenediamine is added dropwise at a uniform speed within 30 to 60 minutes.

[0013] Optionally, the added amount of the composite catalyst is 0.1%-1% of the mass of the stearic acid; the added amount of the antioxidant is 0.1%-0.5% of the mass of the stearic acid.

[0014] Furthermore, the composite catalyst is a mixture of a supported solid of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate and zinc oxide, wherein the mass ratio of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate in the supported solid is 7:2:9:4; and the zinc oxide and the supported solid can be used after being directly mixed in proportion, the particle size of the zinc oxide is less than 20 μm, and the mass ratio of the zinc oxide to the supported solid is (3-7):(4-6). The composite catalyst is easy to separate, will not remain in the product, can be reused, and has a good catalytic effect.

[0015] Furthermore, the carriers of the composite catalyst are chromatographic silica gel and activated alumina, the particle size of the chromatographic silica gel is 100-200 μm, and the pore size is 2-8A; the particle size of the activated alumina is 0.5-1 mm, and the pore size is 30-50A; and the mass ratio of the chromatographic silica gel and the activated alumina is (2-7):(3-6).

[0016] It should be noted that boric acid, phosphoric acid, phosphorous acid and trisodium phosphate are mixed in a certain proportion, the carrier (chromatographic silica gel and activated alumina) is placed in the mixed liquid, and then the temperature is raised to 80°C-100°C, stirred for 8-10h, filtered, and aged at 110°C for 2h to complete the loading of the catalyst.

[0017] In addition, the traditional production process of ethylene bis stearamide is mainly divided into two stages:

[0018] 2C 17 H 35 COOH + H2NCH2CH2NH2 → C 17 H 35 COO - NH3 + CH2CH2NH3 +- OOCC 17 H 35

[0019] C 17 H 35 COO - NH3 + CH2CH2NH3 +- OOCC 17 H 35 →C 17 H 35 COONHCH2CH2NHOOCC 17 H 35 +2H2O

[0020] The ammonium salt intermediate generated in the first stage (salt formation stage) is very easy to color, and the salt formation time is 1.5-2h, which will make the product color value higher, and the ammonium salt will have other side reactions in the second stage (dehydration stage), resulting in a decrease in product purity and a wider melting range. The main reason is that the effect of the catalyst and stabilizer is poor, and there will be a small amount of residual catalyst in ethylene bisstearamide.

[0021] However, the silanol on the surface of the chromatographic silica gel in the present invention can make the ion pairs and standard pairs of the reactants coexist, and this coexistence is the key to the formation of amide bonds, thereby making it easier to form amide bonds and improving the catalytic ability of the acidic catalyst supported thereon; and because the high specific surface area of ​​activated alumina has very high adsorption and catalytic activity, the catalytic ability and stability of the supported acidic catalyst can be improved; and the composite catalyst disclosed in the present invention can be used multiple times without losing activity.

[0022] Furthermore, the antioxidant is sodium borohydride or sodium bisulfate.

[0023] It can be seen from the above technical solution that, compared with the prior art, the preparation process of ethylene bisstearamide provided by the present invention has the following excellent effects:

[0024] The composite catalyst used in the invention has low price, good catalytic effect, no impurities, greatly shortens the time of the salt-forming stage and the dehydration time of synthesizing ethylene bisstearic acid amide, and improves the color and purity of ethylene bisstearic acid amide. DETAILED DESCRIPTION

[0025] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The embodiment of the invention discloses a high-efficiency production process of ethylene bisstearic acid amide.

[0027] In order to better understand the present invention, the present invention is further specifically described below through the following examples, but it should not be understood as a limitation of the present invention. Some non-essential improvements and adjustments made by technicians in this field based on the above invention content are also considered to fall within the protection scope of the present invention.

[0028] The technical solution of the present invention will be further described below in conjunction with specific embodiments.

[0029] Example 1

[0030] 500g of stearic acid was put into a high-pressure reactor, the temperature was raised to 75°C to melt all the stearic acid, nitrogen was introduced to replace the air in the reactor, the temperature was continued to be raised to 120°C, and 2.5g of a composite catalyst was added (the mass ratio of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate was 7:2:9:4, the carrier was chromatographic silica gel and activated alumina, the mass ratio of chromatographic silica gel and activated alumina was 5:5, and the mass ratio of zinc oxide to the supported solid was 5:5), and ethylenediamine was gradually added dropwise to the high-pressure reactor. After the addition was completed, 2g of antioxidant sodium borohydride was added, the temperature was continued to be raised to 190°C for dehydration and drying for 2h, and after dehydration was completed, ethylene bis stearamide was directly sprayed and granulated through a spray granulation tower, and the obtained granular ethylene bis stearamide was collected.

[0031] Example 2

[0032] 500g of stearic acid was put into a high-pressure reactor, the temperature was raised to 75°C to melt all the stearic acid, nitrogen was introduced to replace the air in the reactor, the temperature was raised to 120°C, and 5g of a composite catalyst was added (the mass ratio of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate was 7:2:9:4, the carrier was chromatographic silica gel and activated alumina, the mass ratio of chromatographic silica gel and activated alumina was 5:5, and the mass ratio of zinc oxide to the supported solid was 5:5), and ethylenediamine was gradually added dropwise to the high-pressure reactor. After the addition was completed, 2g of antioxidant sodium bisulfate was added, and the temperature was continued to be raised to 190°C for dehydration and drying for 2h. After the dehydration was completed, ethylene bisstearamide was directly sprayed and granulated through a spray granulation tower, and the obtained granular ethylene bisstearamide was collected.

[0033] Example 3

[0034] 500g of stearic acid was put into a high-pressure reactor, the temperature was raised to 75°C to melt all the stearic acid, nitrogen was introduced to replace the air in the reactor, the temperature was raised to 120°C, and 2.5g of a composite catalyst was added (the mass ratio of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate was 7:2:9:4, the carrier was chromatographic silica gel and activated alumina, the mass ratio of chromatographic silica gel and activated alumina was 3:6, and the mass ratio of zinc oxide to the supported solid was 4:6), ethylenediamine was gradually added dropwise to the high-pressure reactor, 2.5g of antioxidant sodium borohydride was added after the addition was complete, the temperature was continued to rise to 190°C for dehydration and drying for 2h, and after dehydration was complete, ethylene bis stearamide was directly spray granulated through a spray granulation tower, and the obtained granular ethylene bis stearamide was collected.

[0035] In addition, in order to further verify the superior effect of the present invention compared with the prior art, the inventors also conducted the following comparative experiments, the specific operations are as follows:

[0036] Comparative Example 1

[0037] 500g of stearic acid was put into a high-pressure reactor, the temperature was raised to 75°C to melt all the stearic acid, nitrogen was introduced to replace the air in the reactor, the temperature was raised to 120°C, and 2.5g of a composite catalyst was added (the mass ratio of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate was 7:2:9:4, the carrier was chromatographic silica gel and activated alumina, the mass ratio of chromatographic silica gel and activated alumina was 5:5, and zinc oxide was not added), ethylenediamine was gradually added dropwise to the high-pressure reactor, 2g of antioxidant sodium borohydride was added after the dropwise addition was completed, the temperature was continued to be raised to 190°C for dehydration and drying for 2h, and after dehydration was completed, ethylene bis stearamide was directly sprayed granulated by a spray granulation tower, and the obtained granular ethylene bis stearamide was collected.

[0038] Comparative Example 2

[0039] 500g of stearic acid was put into a high-pressure reactor, the temperature was raised to 75°C to melt all the stearic acid, nitrogen was introduced to replace the air in the reactor, the temperature was raised to 120°C, and 2.5g of a composite catalyst was added (the mass ratio of phosphoric acid, phosphorous acid and trisodium phosphate was 10:9:4, the carrier was chromatographic silica gel, and the mass ratio of zinc oxide to the supported solid was 5:5), ethylenediamine was gradually added dropwise to the high-pressure reactor, 2g of antioxidant sodium borohydride was added after the addition was completed, the temperature was continued to be raised to 190°C for dehydration and drying for 2h, and after dehydration was completed, ethylene bis stearamide was directly sprayed and granulated through a spray granulation tower, and the obtained granular ethylene bis stearamide was collected.

[0040] Comparative Example 3

[0041] 500g of stearic acid was put into a high-pressure reactor, the temperature was raised to 75°C to melt all the stearic acid, nitrogen was introduced to replace the air in the reactor, the temperature was raised to 120°C, and 2.5g of a composite catalyst was added (the mass ratio of phosphoric acid, phosphorous acid and trisodium phosphate was 2:9:1, the carrier was activated alumina, and no zinc oxide was added), ethylenediamine was gradually added dropwise to the high-pressure reactor, and 2g of antioxidant sodium borohydride was added after the addition was completed, the temperature was continued to be raised to 190°C for dehydration and drying for 2h, and after dehydration was completed, ethylene bis stearamide was directly sprayed and granulated through a spray granulation tower, and the obtained granular ethylene bis stearamide was collected.

[0042] The ethylene bisstearic acid amide synthesized in the above examples and comparative examples was tested for relevant indicators, as shown in the following table.

[0043]

[0044] The ethylene bisstearic acid amide produced by the invention has a simple process flow, few reaction control points, is easy to operate, has a good color and high purity for the synthesized product, and its acid value, amine value and other indicators are all better than those of superior products in industry standards.

[0045] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A preparation process of ethylene bisstearic acid amide, characterized in that: The process specifically comprises the following steps: 1) Put stearic acid into the reactor, heat it to 60℃-100℃ and melt it; 2) After the stearic acid in step 1) is completely melted, the temperature is raised to 100°C-120°C, nitrogen is introduced to replace the air in the reactor, and after adding the composite catalyst, ethylenediamine is gradually added dropwise into the reactor; 3) After the addition of ethylenediamine in step 2) is completed, an antioxidant is added, the temperature is continued to be raised, and dehydration and drying is performed at 180° C.-200° C. for 1-3 hours to obtain the ethylene bisstearic acid amide; The composite catalyst is a mixture of supported solids of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate and zinc oxide, wherein the mass ratio of boric acid, phosphoric acid, phosphorous acid and trisodium phosphate in the supported solid is 7:2:9:4, the particle size of zinc oxide is less than 20 μm, and the mass ratio of zinc oxide to supported solid is (3-7):(4-6); The carriers of the composite catalyst are chromatographic silica gel and activated alumina, the particle size of the chromatographic silica gel is 100-200 μm, and the pore size is 2-8 Å; the particle size of the activated alumina is 0.5-1 mm, and the pore size is 30-50 Å; and the mass ratio of the chromatographic silica gel to the activated alumina is (2-7): (3-6).

2. The preparation process of ethylene bisstearamide according to claim 1, characterized in that: The molar ratio of the stearic acid to the ethylenediamine is 2:1.05-1.25, and the ethylenediamine is added dropwise at a uniform speed within 30 to 60 minutes.

3. A preparation process of ethylene bisstearamide according to claim 1, characterized in that, The added amount of the composite catalyst is 0.1%-1% of the mass of the stearic acid; the added amount of the antioxidant is 0.1%-0.5% of the mass of the stearic acid.

4. A preparation process of ethylene bisstearamide according to claim 1 or 3, characterized in that, The antioxidant is sodium borohydride or sodium bisulfate.

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