A composite microsphere catalyst and its preparation method and phosphorus-free dimer acid preparation method

Abstract

The invention discloses a composite microsphere catalyst and its preparation method and phosphorus-free dimer acid preparation method, wherein the composite microsphere catalyst is composed of the following components: 50 parts by weight of sodium lignin sulfonate, 50 parts by weight of formaldehyde, 10 parts by weight of suspending agent, 2 parts by weight of ammonia, 10 to 30 parts by weight of modifier and 3 to 10 parts by weight of concentrated sulfuric acid. The present invention uses industrial waste sodium lignin sulfonate and formaldehyde to react to obtain a prepolymer, then introduces an active alkali metal salt, and the C-based microspheres of Lewis acid sites (cations such as Co, Al, Ti) are loaded by a hydrothermal method, and concentrated sulfuric acid is then used for sulfonation, and acid sites are introduced to the surface, and by Lewis acid sites and acid sites, the high specific surface area and adsorption capacity of porous carbon microspheres are coordinated, and the catalytic efficiency of Diels‑Alder reaction is improved, while organic acid is used to replace phosphoric acid for later acidification.

Description

Technical Field

[0001] The invention relates to the technical field of dimer acid preparation, and in particular to a composite microsphere catalyst and a preparation method thereof and a phosphorus-free dimer acid preparation method. Background Art

[0002] Dimer acid is a transparent viscous liquid with the advantages of being non-toxic, thermally stable and renewable. It is an indispensable raw material for the preparation of fine chemical products such as polyamide resins, epoxy resin improvers, fuel oils and cutting oil additives. It has been widely used in printed circuit boards, inks, surfactants, lubricants, plastic plasticizers and other fields.

[0003] At present, the dimer acid widely used in industry is prepared by using activated clay as a catalyst and lithium carbonate as a co-catalyst, and then obtaining fine dimer acid by acidification, filtration, water washing, distillation and other methods. Activated clay comes from nature, has poor quality stability, and brings a large amount of metal ions into the product, forming saponification under high temperature conditions, deepening the color of the product and affecting the quality of the product. The traditional method is to add phosphoric acid to the crude dimer acid product for acidification, water washing and filtration, which brings a large amount of phosphorus-containing wastewater. At the same time, the activated clay after the reaction cannot be reused, generating a large amount of solid hazardous waste.

[0004] Patent CN115845891 discloses a composite catalyst, which adds Li2CO3 and Al2O3 to change the structure of activated clay, thereby increasing the yield of dimer acid reactants, but the use of clay still produces a large amount of waste solids. Patent CN101492358 reports a method for producing low-phosphorus dimer acid, which separates excess phosphate from the dimer acid system by adding washing and centrifugal separation steps, so that the phosphate content in the fine dimer acid is reduced to less than 30μg / g. However, this method requires a large amount of water washing and centrifugal separation, which not only increases production costs, but also produces a large amount of phosphorus-containing wastewater. Summary of the invention

[0005] To this end, the technical problem to be solved by the present invention is to provide a composite microsphere catalyst and a preparation method thereof and a phosphorus-free dimer acid preparation method, wherein a prepolymer is obtained by reacting industrial waste sodium lignin sulfonate with formaldehyde, and then an active alkali metal salt is introduced to load Lewis acid sites (Co, Al, Ti and other cations) on the C-based microspheres by a hydrothermal method, and then concentrated sulfuric acid is used for sulfonation to introduce the prepolymer into the surface. Acid sites, through Lewis acid sites and The acid sites work together with the high specific surface area and adsorption capacity of the porous carbon microspheres to improve the catalytic efficiency of the Diels-Alder reaction, while organic acids are used instead of phosphoric acid for the subsequent acidification treatment.

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

[0007] A composite microsphere catalyst consists of the following components: 50 parts by weight of sodium lignin sulfonate, 50 parts by weight of formaldehyde, 10 parts by weight of suspending agent, 2 parts by weight of ammonia water, 10 to 30 parts by weight of modifier and 3 to 10 parts by weight of concentrated sulfuric acid.

[0008] In the composite microsphere catalyst, the modifier is one or more of tetrabutyl titanate, aluminum trichloride and cobalt chloride.

[0009] The composite microsphere catalyst, the suspending agent is one or more of polyvinyl alcohol, hydroxyethyl cellulose and polyacrylamide.

[0010] The preparation method of the composite microsphere catalyst comprises the following steps:

[0011] S1) preparing materials: preparing 50 parts by weight of sodium lignin sulfonate, 50 parts by weight of formaldehyde, 10 parts by weight of suspending agent, 2 parts by weight of ammonia water, 10 to 30 parts by weight of modifier and 3 to 10 parts by weight of concentrated sulfuric acid;

[0012] S2) adding the sodium lignosulfonate, formaldehyde, suspending agent and ammonia water prepared in step S1) into a reaction kettle, heating to 50° C. and keeping the temperature for 5 hours under stirring to obtain a first mixed solution;

[0013] S3) adding a modifier to the first mixed solution and stirring and mixing to obtain a second mixed solution;

[0014] S4) pouring the second mixed solution into a hydrothermal reaction kettle, performing a hydrothermal reaction at 200° C. for 10 h, filtering and drying to obtain a dried product;

[0015] S5) The dried product obtained in step S4) is placed in a tubular furnace and sintered in an argon atmosphere for 4 hours to obtain composite porous microspheres, and the sintering temperature is 550° C.;

[0016] S6) 100 parts by weight of the composite porous microspheres prepared in step S5) and 100 parts by weight of deionized water are added to a reaction kettle, the temperature is raised to 80° C., and then 3 to 10 parts by weight of concentrated sulfuric acid are added dropwise. The reaction is kept warm for 10 hours, filtered and dried to obtain a composite microsphere catalyst.

[0017] In the preparation method of the above-mentioned composite microsphere catalyst, in step S5), when sintering the dried product, the dried product is sintered in stages, specifically: the first stage is heated to 350°C and kept warm for 2 hours, the second stage is heated to 550°C and kept warm for 2 hours, and the heating rate of the first stage and the heating rate of the second stage are both 2°C / min.

[0018] In the preparation method of the composite microsphere catalyst, the modifier is one or more of tetrabutyl titanate, aluminum trichloride and cobalt chloride.

[0019] The preparation method of the composite microsphere catalyst, wherein the suspending agent is one or more of polyvinyl alcohol, hydroxyethyl cellulose and polyacrylamide

[0020] A method for preparing phosphoric acid-free dimer acid using the composite microsphere catalyst comprises the following steps:

[0021] Step 1) preparing materials: 100 parts by weight of vegetable oleic acid, 10-30 parts by weight of composite microsphere catalyst, 0.2-1 parts by weight of co-catalyst lithium carbonate, and 1-3 parts by weight of organic acid;

[0022] Step S2) adding 10 to 30 parts by weight of a composite microsphere catalyst and 0.2 to 1 part by weight of lithium carbonate to 100 parts by weight of vegetable oil acid, and adding 1 to 2 parts by weight of water, stirring thoroughly, heating to 180 to 220° C. at 1 to 10 atmospheres, polymerizing for 2 to 3 hours to obtain a crude dimer acid;

[0023] Step 3) The crude dimer acid obtained in step 2) is transferred to an acidification kettle, and 1 to 3 parts by weight of an organic acid is added dropwise at 120° C. for 3 hours to perform acidification, and then filtered to obtain the acidified crude dimer acid;

[0024] Step 4) The acidified crude dimer acid obtained in step 3) is washed with water at 90°C, then centrifuged and dehydrated, and then placed in a thin film evaporator for drying at 120°C, and then placed in a short-path distiller for separation at a temperature of 220°C and a vacuum degree of 30Pa to obtain the final product dimer acid.

[0025] In the above method, the vegetable oleic acid is one or more of soybean oleic acid, tall oil acid and cottonseed oleic acid.

[0026] In the above method, the organic acid is one or more of oxalic acid, formic acid and acetic acid.

[0027] The technical solution of the present invention achieves the following beneficial technical effects:

[0028] 1. The composite microsphere catalyst of the present invention is easy to filter and recover, and can be reused through high-temperature carbonization treatment in the later stage, thereby reducing the emission of three wastes in the production process.

[0029] 2. The prepolymer is obtained by reacting sodium lignin sulfonate from industrial waste with formaldehyde, and then active alkali metal salts are introduced to load Lewis acid sites (Co, Al, Ti and other cations) on C-based microspheres by hydrothermal method, and then sulfonated with concentrated sulfuric acid to introduce Acid sites, through Lewis acid sites and The acid sites work together with the high specific surface area and adsorption capacity of the porous carbon microspheres to improve the catalytic efficiency of the DielsAlder reaction. At the same time, the use of organic acid instead of phosphoric acid for the subsequent acidification treatment can improve the quality of the dimer acid product while eliminating phosphoric acid in the dimer acid. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a TEM image of the composite microsphere catalyst prepared in specific example 1. DETAILED DESCRIPTION

[0031] Example 1

[0032] Preparation of composite microsphere catalyst: 100 parts by weight of sodium lignin sulfonate, 50 parts by weight of formaldehyde, 10 parts by weight of polyvinyl alcohol and 2 parts by weight of ammonia water are added to a reactor, heated to 50°C under stirring conditions and kept warm for 5 hours, then 10 parts by weight of tetrabutyl titanate are added and mixed, poured into a hydrothermal reactor, and hydrothermally reacted at 200°C for 10 hours, filtered and dried; the dried product is placed in a tubular furnace, and under an argon atmosphere, the heating rate is 2°C / min throughout the process, first raised to 350°C, kept warm for 2 hours, and then raised to 550°C, kept warm for 2 hours, to obtain composite porous microspheres; then 100 parts by weight of the composite porous microspheres are added to the reactor, 100 parts by weight of deionized water are added, the temperature is raised to 80°C, 3 parts by weight of concentrated sulfuric acid are added dropwise, kept warm for 10 hours, filtered and dried, and the final composite microsphere catalyst is obtained. The TEM image of the prepared composite microsphere catalyst is as follows Figure 1 shown.

[0033] Preparation of phosphorus-free dimer acid: 100 parts by weight of soybean oleic acid is put into a reaction kettle, 10 parts by weight of a composite microsphere catalyst and 0.2 parts by weight of lithium carbonate are added, a small amount of water is added, the mixture is fully stirred and mixed, and the mixture is heated to 180° C. for polymerization for 3 hours under 1 atmosphere to obtain a crude dimer acid; the mixture is transferred to an acidification kettle, 1 part by weight of oxalic acid is added dropwise at a temperature of 120° C. for acidification, and the mixture is filtered after the acidification time of 3 hours; the filtered dimer acid is washed with water at a temperature of 90° C., centrifugally dehydrated, and then dried in a thin film evaporator at a temperature of 120° C., and then separated in a short-path distiller at a vacuum degree of less than 30 Pa at 220° C. to obtain the final dimer acid.

[0034] When the catalytic efficiency of the composite microsphere catalyst in this embodiment decreases after repeated use, the catalytic efficiency can be restored by high-temperature carbonization treatment.

[0035] Example 2

[0036] The difference between the preparation method of the hydrothermal composite microsphere catalyzed phosphorus-free dimer acid in this embodiment and that in embodiment 1 is that the modifier used to prepare the composite microsphere catalyst in this embodiment is aluminum chloride.

[0037] Example 3

[0038] The difference between the preparation method of the hydrothermal composite microsphere catalyzed phosphorus-free dimer acid in this embodiment and that in Embodiment 1 is that the modifier used to prepare the composite microsphere catalyst in this embodiment is cobalt chloride.

[0039] Example 4

[0040] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that the amount of the modifier used to prepare the composite microsphere catalyst in this embodiment is 20 parts by weight.

[0041] Example 5

[0042] The difference between the preparation method of the hydrothermal composite microsphere catalyzed phosphorus-free dimer acid in this embodiment and that in Embodiment 1 is that the amount of the modifier used to prepare the composite microsphere catalyst in this embodiment is 30 parts by weight.

[0043] Example 6

[0044] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that the suspending agent used to prepare the composite microsphere catalyst in this embodiment is hydroxyethyl cellulose.

[0045] Example 7

[0046] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that the suspending agent used to prepare the composite microsphere catalyst in this embodiment is polyacrylamide.

[0047] Example 8

[0048] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that the plant oleic acid used in the preparation of phosphorus-free dimer acid in this embodiment is tall oil acid.

[0049] Example 9

[0050] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that the vegetable oleic acid used in the preparation of phosphorus-free dimer acid in this embodiment is cottonseed oleic acid.

[0051] Example 10

[0052] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that the organic acid used in preparing the phosphorus-free dimer acid in this embodiment is formic acid.

[0053] Embodiment 11

[0054] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that the organic acid used in preparing the phosphorus-free dimer acid in this embodiment is acetic acid.

[0055] Example 12

[0056] The difference between the method for preparing phosphorus-free dimer acid catalyzed by composite microspheres using a hydrothermal method in this embodiment and that in Example 1 is that 20 parts by weight of the composite microsphere catalyst is used in preparing the phosphorus-free dimer acid in this embodiment.

[0057] Example 13

[0058] The difference between the method for preparing phosphorus-free dimer acid catalyzed by composite microspheres using a hydrothermal method in this embodiment and that in Example 1 is that 30 parts by weight of the composite microsphere catalyst is used in preparing the phosphorus-free dimer acid in this embodiment.

[0059] Embodiment 14

[0060] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that 0.5 parts by weight of lithium carbonate is used in preparing the phosphorus-free dimer acid in this embodiment.

[0061] Embodiment 15

[0062] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that 1 part by weight of lithium carbonate is used in preparing the phosphorus-free dimer acid in this embodiment.

[0063] Example 16

[0064] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that 2 parts by weight of organic acid are used in preparing the phosphorus-free dimer acid in this embodiment.

[0065] Embodiment 17

[0066] The difference between the method for preparing phosphorus-free dimer acid catalyzed by hydrothermal composite microspheres in this embodiment and that in Example 1 is that 3 parts by weight of organic acid are used in preparing the phosphorus-free dimer acid in this embodiment.

[0067] Comparative Example

[0068] The difference between this comparative example and Example 1 is that the catalyst used in the process of preparing dimer acid is activated clay.

[0069] Test Method

[0070] Color: tested using 581-S photoelectric colorimeter.

[0071] Viscosity: The test sample was controlled at 25±0.2°C in a constant temperature oil bath and tested using a rotational viscometer.

[0072] Composition: The sample is dissolved in tetrahydrofuran, the bubbles are removed by ultrasonic vibration, and the test is performed by liquid gel chromatography.

[0073] Electron microscope photo: The microsphere samples were tested using a transmission scanning electron microscope.

[0074] Physical properties of dimer acid of Examples 1-17 and Comparative Examples

[0075]

[0076] It can be seen from the data recorded in Table 1 that the dimer acid prepared by using the composite microsphere catalyst of the present invention has better color, increased dimer content, and in most cases decreased trimer and monomer content.

[0077] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. A composite microsphere catalyst, characterized in that: The composite microsphere catalyst is composed of the following components: 50 parts by weight of sodium lignin sulfonate, 50 parts by weight of formaldehyde, 10 parts by weight of a suspending agent, 2 parts by weight of ammonia water, 10 to 30 parts by weight of a modifier and 3 to 10 parts by weight of concentrated sulfuric acid, wherein the modifier is one or more of tetrabutyl titanate, aluminum trichloride and cobalt chloride, and the suspending agent is one or more of polyvinyl alcohol, hydroxyethyl cellulose and polyacrylamide; the composite microsphere catalyst is prepared by the following steps: S1) preparing materials: preparing 50 parts by weight of sodium lignin sulfonate, 50 parts by weight of formaldehyde, 10 parts by weight of suspending agent, 2 parts by weight of ammonia water, 10 to 30 parts by weight of modifier and 3 to 10 parts by weight of concentrated sulfuric acid; S2) adding the sodium lignin sulfonate, formaldehyde, suspending agent and ammonia water prepared in step S1) into a reaction kettle, heating to 50° C. and keeping the temperature for 5 hours under stirring to obtain a first mixed solution; S3) adding a modifier to the first mixed solution and stirring and mixing to obtain a second mixed solution; S4) pouring the second mixed solution into a hydrothermal reaction kettle, performing a hydrothermal reaction at 200° C. for 10 h, filtering and drying to obtain a dried product; S5) placing the dried product obtained in step S4) in a tubular furnace and sintering it in an argon atmosphere for 4 hours to obtain composite porous microspheres; when sintering the dried product, the dried product is sintered in stages, specifically: the first stage is heated to 350°C and kept warm for 2 hours, the second stage is heated to 550°C and kept warm for 2 hours, and the heating rate of the first stage and the heating rate of the second stage are both 2°C / min; S6) 100 parts by weight of the composite porous microspheres prepared in step S5) and 100 parts by weight of deionized water are added to a reaction kettle, the temperature is raised to 80° C., and then 3 to 10 parts by weight of concentrated sulfuric acid are added dropwise. The reaction is kept warm for 10 hours, filtered and dried to obtain a composite microsphere catalyst.

2. The method for preparing the composite microsphere catalyst according to claim 1, characterized in that: The steps include: S1) preparing materials: preparing 50 parts by weight of sodium lignin sulfonate, 50 parts by weight of formaldehyde, 10 parts by weight of suspending agent, 2 parts by weight of ammonia water, 10 to 30 parts by weight of modifier and 3 to 10 parts by weight of concentrated sulfuric acid; S2) adding the sodium lignin sulfonate, formaldehyde, suspending agent and ammonia water prepared in step S1) into a reaction kettle, heating to 50° C. and keeping the temperature for 5 hours under stirring to obtain a first mixed solution; S3) adding a modifier to the first mixed solution and stirring and mixing to obtain a second mixed solution; S4) pouring the second mixed solution into a hydrothermal reaction kettle, performing a hydrothermal reaction at 200° C. for 10 h, filtering and drying to obtain a dried product; S5) placing the dried product obtained in step S4) in a tubular furnace and sintering it in an argon atmosphere for 4 hours to obtain composite porous microspheres; when sintering the dried product, the dried product is sintered in stages, specifically: the first stage is heated to 350°C and kept warm for 2 hours, the second stage is heated to 550°C and kept warm for 2 hours, and the heating rate of the first stage and the heating rate of the second stage are both 2°C / min; S6) 100 parts by weight of the composite porous microspheres prepared in step S5) and 100 parts by weight of deionized water are added to a reaction kettle, the temperature is raised to 80° C., and then 3 to 10 parts by weight of concentrated sulfuric acid are added dropwise. The reaction is kept warm for 10 hours, filtered and dried to obtain a composite microsphere catalyst.

3. A method for preparing phosphoric acid-free dimer acid using the composite microsphere catalyst according to claim 1, characterized in that: The steps include: Step 1) preparing materials: 100 parts by weight of vegetable oleic acid, 10-30 parts by weight of composite microsphere catalyst, 0.2-1 parts by weight of co-catalyst lithium carbonate, and 1-3 parts by weight of organic acid; Step S2) adding 10 to 30 parts by weight of a composite microsphere catalyst and 0.2 to 1 part by weight of lithium carbonate to 100 parts by weight of vegetable oil acid, and adding 1 to 2 parts by weight of water, stirring thoroughly, heating to 180 to 220° C. at 1 to 10 atmospheres, polymerizing for 2 to 3 hours to obtain a crude dimer acid; Step 3) The crude dimer acid obtained in step 2) is transferred into an acidification kettle, and 1 to 3 parts by weight of an organic acid is added dropwise at 120° C. for 3 hours to perform acidification, and then filtered to obtain the acidified crude dimer acid; Step 4) The acidified crude dimer acid obtained in step 3) is washed with water at 90°C, then centrifuged and dehydrated, and then placed in a thin film evaporator for drying at 120°C, and then placed in a short-path distiller for separation at a temperature of 220°C and a vacuum degree of 30Pa to obtain the final product dimer acid.

4. The method according to claim 3, characterized in that The vegetable oleic acid is one or more of soybean oleic acid, tall oil acid and cottonseed oleic acid.

5. The method according to claim 3, characterized in that: The organic acid is one or more of oxalic acid, formic acid and acetic acid.

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