Modified hydrolyzed fillers, their preparation methods and applications, and methods for preparing formaldehyde-formic acid aqueous solutions.

Abstract

This invention relates to the technical field of aldehyde fatty acid esters, and discloses a modified hydrolysis filler, its preparation method and application, and a method for preparing formaldehyde-formic acid aqueous solution. The modified hydrolysis filler comprises a silane layer and an activation layer sequentially coated on the outer surface of the filler from the inside out; the activation layer includes amide groups, phenolic hydroxyl groups, sulfone groups, carboxylic acid groups, and sulfonic acid groups. The modified hydrolysis filler, with its outer surface coated with a silane layer and an activation layer, exhibits excellent catalytic hydrolysis characteristics.

Description

Technical Field

[0001] This invention relates to the technical field of aldehyde fatty acid esters, specifically to a modified hydrolyzable filler and its preparation and application, and a method for preparing formaldehyde-formic acid aqueous solution. Background Technology

[0002] Formaldehyde esters are important intermediates widely used in the pharmaceutical and chemical industries. They can be used to prepare intermediates for liver disease drugs such as ledipasvir, chemical raw materials such as D-pantolytic acid lactone, and are also widely used in the production of sun-protective coatings for aluminum alloy doors and windows. The main production methods for formaldehyde esters include the ozone oxidation of dimethyl maleate, the periodic acid oxidation of dimethyl tartrate, the alkyl exchange method with glyoxylic acid monohydrate and dimethoxyglyoxylate, and the hydrogen peroxide oxidation method of acrylates. With the development of coal chemical technology, the co-production of glycol from syngas and the oxidation of glycolic acid to formaldehyde esters has gradually become the main process route.

[0003] Formaldehyde esters can be hydrolyzed to formaldehyde formic acid, also known as dihydroxyacetic acid or glyoxylic acid. It is the simplest aldehyde acid, possessing both aldehyde and carboxyl functional groups in its molecule. It can react with both aldehydes and acids simultaneously, and can also undergo cyclization and condensation reactions. Formaldehyde formic acid is chemically quite reactive and can be used to produce organic intermediates for fragrances, pharmaceuticals, pesticides, food, varnish raw materials, dyes, and plastic additives. It can also be used in the production of oral penicillin, vanillin, ethyl vanillin, mandelic acid, and allantoin.

[0004] Formaldehyde ester hydrolysis generally employs fixed-bed or reactive distillation catalytic hydrolysis. For example, patent application CN112778118A describes a method for preparing glyoxylic acid from methyl glycolate: a mixture containing methyl glycolate, fluorinated alcohols or trifluoroacetic acid, and water is reacted with an oxidation catalyst and a hydrolysis catalyst in the presence of an oxygen source to obtain glyoxylic acid; the hydrolysis catalyst is selected from sulfonic acid resin Amberlyst-15, sulfonic acid resin Amberlyst-35, heteropoly acids, and metal oxide-supported SO4. 2- Solid superacid, metal oxide supported S2O8 2- At least one of solid superacids. Patent application CN112898148A discloses a process method and apparatus for the purification of glyoxylic acid, which includes the following: using water to absorb the process gas containing glyoxylate from the reaction system to form an aqueous solution of glyoxylate, which is then sequentially fed into a pre-hydrolysis reactor and a hydrolysis tower for hydrolysis; the hydrolysis catalyst is a solid acid.

[0005] Formaldehyde-formic acid (PFCA) is used in high-end applications such as the production of pharmaceutical intermediates, fragrances, and polymer monomers, where high quality is required. However, PFCA exhibits characteristics such as easy polymerization upon heating, easy decomposition upon heating, extremely low volatility, and easy hydration, significantly limiting separation methods. During the hydrolysis of PFCA esters, if the water-to-ester ratio is high, both fixed-bed hydrolysis and reactive distillation processes face the challenge of aqueous solution concentration and dehydration in the later stages. This dehydration and concentration process leads to polymerization of the heat-sensitive PFCA, deepening of solution color, and thermal decomposition. For high-end applications, such as pharmaceutical intermediates, fragrances, and biodegradable materials, oligomers and colored impurities in the PFCA product can significantly impact the color, purity, and polymer physicochemical properties of the intermediates. Therefore, low-water-ratio hydrolysis technology for PFCA esters is one of the important ways to improve the quality of PFCA products. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of high water-to-ester ratio and high oligomer content in the formaldehyde-formaldehyde ester hydrolysis process and subsequent concentration process in the prior art. It provides a modified hydrolysis filler and its preparation method and application, as well as a method for preparing formaldehyde-formaldehyde aqueous solution. The modified hydrolysis filler has a silane layer and an activation layer coated on its outer surface and has excellent catalytic hydrolysis characteristics.

[0007] To achieve the above objectives, the first aspect of the present invention provides a modified hydrolysis filler, characterized in that the modified hydrolysis filler comprises a silane layer and an activation layer sequentially coated on the outer surface of the filler from the inside out; the activation layer comprises amide groups, phenolic hydroxyl groups and sulfone groups, carboxylic acid groups and sulfonic acid groups.

[0008] Preferably, in the activated layer, the content of amide groups is 5-20 mmol / m² based on the surface area of ​​the dry-based filler. 2 The content of carboxylic acid groups and sulfonic acid groups is 15-80 mmol / m. 2 The content of phenolic hydroxyl and sulfone groups is 2-62 mmol / m 2 .

[0009] A second aspect of the present invention provides a method for preparing a modified hydrolysis filler, wherein the method includes:

[0010] (1) The packing is subjected to silanization treatment to obtain a packing coated with a silane layer;

[0011] (2) The filler coated with silane layer is activated at least once using an activating component to obtain a modified hydrolytic filler;

[0012] The activated component contains amide groups, phenolic hydroxyl groups, sulfone groups, carboxylic acid groups, and sulfonic acid groups.

[0013] The third aspect of this invention provides the application of the modified hydrolyzed filler described in the first aspect or the modified hydrolyzed filler prepared by the preparation method described in the second aspect in aldehyde fatty acid esters.

[0014] The fourth aspect of the present invention provides a method for preparing an aqueous solution of formaldehyde-formic acid, wherein the method includes contacting the modified hydrolytic filler described in the first aspect or the modified hydrolytic filler prepared by the preparation method described in the second aspect with formaldehyde-formic acid ester to carry out a hydrolysis reaction.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] During the experimental research, the inventors of this invention discovered that resin-based solid acid hydrolysis catalysts exhibit better long-term operational stability compared to supported catalysts prepared by processes such as impregnation, with virtually no loss of the activating component in the liquid phase system. Formaldehyde-formic acid is a component with strong thermosensitive activation; it easily polymerizes and produces colored impurities at high temperatures and concentrations. Therefore, a relatively large water-to-ester ratio is generally chosen during the hydrolysis of formaldehyde-formic acid esters, resulting in significantly higher water consumption relative to the stoichiometric theoretical water consumption or the water consumption required for product specifications. This leads to a lower concentration of the formaldehyde-formic acid hydrolysate, necessitating the addition of a formaldehyde-formic acid concentration tower or a longer residence time in the bottom of a reactive distillation column. Overall, this results in a longer residence time of the thermosensitive formaldehyde-formic acid in the high-temperature distillation and concentration environment, leading to a higher concentration of formaldehyde-formic acid oligomers and a decline in product quality. This invention enhances the microscopic water environment distribution, thereby reducing the macroscopic water-to-ester molar ratio.

[0017] In this invention, a silane layer and an activation layer are sequentially coated on the outer surface of the packing material. The (-Si-O-metal) chemical bonds on the metal surface of the packing material have good stability, which can prevent the activation layer from peeling and cracking. The single-use cycle is more than two years (it can be repaired during major equipment overhauls). At the same time, due to its thin thickness, it has little impact on the outer surface area of ​​the packing material. However, after coating the outer surface of the packing material with a silane layer, the corrosion resistance in acidic environments is significantly increased, which can reduce the release of metal ions from the equipment, thereby reducing the polymerization activation effect on heat-sensitive formaldehyde formaldehyde acid and reducing the content of metal ions in the product, thus improving product quality. Furthermore, the activation layer contains hydrophilic groups, repulsive groups, and catalytic groups. The various groups in the activation layer are overlapped and distributed to form a sandwich-like structure, ensuring that the activation layer has an appropriate thickness. This ensures an effective combination of "water-rich", "catalytic", and "diffusion", avoiding excessive thickness and allowing formaldehyde formaldehyde ester, formaldehyde formaldehyde acid, and water to have good diffusion effects. Detailed Implementation

[0018] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0019] The first aspect of the present invention provides a modified hydrolysis filler, wherein the modified hydrolysis filler comprises a silane layer and an activation layer sequentially coated on the outer surface of the filler from the inside out; the activation layer comprises amide groups, phenolic hydroxyl groups and sulfone groups, carboxylic acid groups and sulfonic acid groups.

[0020] In this invention, a silane layer and an activation layer are sequentially coated on the outer surface of the filler. The silane layer acts as a bridge between the filler matrix and the activation layer. On the one hand, the filler matrix and the silane layer form (-Si-O-metal) chemical bonds, improving the acid corrosion resistance of the filler. On the other hand, the various groups in the silane layer and the activation layer cooperate with each other. The activation layer contains hydrophilic groups, repulsive groups, and catalytic groups, thus obtaining a modified hydrolysis filler. The hydrophilic groups, repulsive groups, and catalytic groups cause the surface of the modified filler to form a "sandwich" structure. Therefore, the modified hydrolysis filler has an effective combination of "water-rich", "catalytic", and "diffusion" properties, avoiding excessive thickness of the activation layer. When applied to the formaldehyde formaldehyde ester hydrolysis reaction, it can promote the hydrolysis of formaldehyde formaldehyde ester, improve the quality of formaldehyde formaldehyde products, and reduce the content of formaldehyde formaldehyde oligomers.

[0021] In this invention, it is understood that the silane layer and activation layer mentioned in this invention refer to the silane layer and activation layer coated on the outer surface of the filler, excluding the situation inside the filler. During the preparation process, it is inevitable that silane and activation components will exist inside the filler, and this invention does not make any special limitation on this.

[0022] In this invention, the amide groups, phenolic hydroxyl groups, and sulfone groups in the activated layer were determined by infrared spectroscopy. The specific testing conditions were KBr pellet compression at 400 cm⁻¹. -1 -4000cm -1 Scanning within the range; carboxylic acid and sulfonic acid groups were determined by titration, specifically by direct titration with 0.1 mol / L sodium hydroxide solution.

[0023] In this invention, it is understood that the activation layer can be obtained through repeated processing. Preferably, the activation layer includes at least one activation unit, the activation unit including activation layer A and activation layer B, activation layer A including amide groups, phenolic hydroxyl groups and sulfone groups, and activation layer B including carboxylic acid groups and sulfonic acid groups.

[0024] In this invention, it is understood that the activation layer including at least one activation unit means that the activation layer may contain multiple activation units, and each activation unit contains activation layer A and activation layer B. That is, the activation layer exists in the form of an alternating structure of activation layer A and activation layer B, and activation layer A and activation layer B. In this invention, the number of alternations is not specifically limited, and those skilled in the art can adjust it according to actual needs.

[0025] In a preferred embodiment, the activation layer A and the activation layer B are sequentially coated on the surface of the silane layer.

[0026] In this invention, the amide groups in the activated layer A act as hydrophilic groups, exhibiting excellent water absorption and swelling effects in formaldehyde ester aqueous solutions. After water absorption and swelling, they form a water-rich bulk structure, which can increase the water content relative to the bulk liquid phase by tens or even hundreds of times. Even in hydrolysis scenarios with low water-to-ester ratio formulations, this modified microstructure can still maintain a rich water content. Simultaneously, functional groups such as phenolic hydroxyl and sulfone groups, which have a repulsive effect on formaldehyde ester molecules, are grafted into this structure, significantly reducing the solubility of formaldehyde ester within the structure. This allows the formaldehyde ester produced during hydrolysis to diffuse promptly into the bulk liquid phase, promoting the continuous rightward shift of the hydrolysis equilibrium and resulting in near-complete hydrolysis of the formaldehyde ester.

[0027] Furthermore, the carboxylic acid groups and sulfonic acid groups in the activated layer B serve as catalytic groups, mainly playing a catalytic role in the hydrolysis of formaldehyde formate. From the perspective of hydrolysis conversion rate alone, the sulfonic acid groups have a good hydrolysis catalytic effect. However, the sulfonic acid groups also play a catalytic role in the polymerization of the hydrolysis product formaldehyde formic acid. This invention has found that by combining a certain amount of carboxylic acid groups, through the synergistic catalytic effect between sulfonic acid groups and carboxylic acid groups, a good balance effect can be achieved in the hydrolysis of formaldehyde formate and the polymerization of formaldehyde formic acid under a micro-water-rich environment.

[0028] In this invention, by overlapping activation layer A and activation layer B, a suitable thickness of a "sandwich" structure as described above is formed, which can ensure the effective combination of "water richness", "catalysis" and "diffusion", avoid excessive activation layer thickness, and enable formaldehyde ester, formaldehyde formic acid and water to have good diffusion effect.

[0029] In this invention, there is no particular limitation on the type of packing. The packing is a grid-structured packing and / or a corrugated structured packing. For example, the corrugated structured packing can be a plate corrugated structured packing and / or a mesh corrugated structured packing, such as at least one of calendered perforated plate corrugated structured packing, mesh grid-structured packing, and corrugated wire mesh structured packing.

[0030] In this invention, preferably, the filler material is metal, such as 304, 304L, 316, or 316L.

[0031] In a preferred embodiment, the packing material is a structured metal corrugated wire mesh packing. In this invention, using structured metal corrugated wire mesh packing as the matrix material can reduce the pressure drop in the reactor, effectively control the pressure range and corresponding operating temperature at the bottom of the reactive distillation column or the other end of the reactor, and improve the quality of the target product.

[0032] In this invention, there is no particular limitation on the specific surface area of ​​the packing material. Preferably, the specific surface area of ​​the packing material is 800-2300 m². 2 / m 3 .

[0033] In a preferred embodiment, the molar ratio of groups (-Si-O-Si-) to groups (-Si-OM) in the silane layer is 1.3-4.2; wherein M is a metal derived from the filler.

[0034] In this invention, the groups (-Si-O-Si-) and (-Si-OM) are determined by infrared spectroscopy. Specific test conditions include: KBr pellet compression at 400 cm⁻¹. -1 -4000cm -1 Scan within the range.

[0035] In a preferred embodiment, the thickness of the silane layer is 2-6 micrometers. In this invention, the thickness of the silane layer is measured using an X-ray fluorescence thickness gauge.

[0036] By matching the molar ratio of the groups (-Si-O-Si-) to the groups (-Si-OM) and the thickness of the silane layer as described above, it is possible to achieve both high strength and avoid excessive thickness, which would lead to a significant reduction in the surface area of ​​the filler.

[0037] In a preferred embodiment, the silane layer is provided by at least one of 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl methacrylate, 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl acrylate, and 3-(isobutenoyloxy)propyltrimethoxysilane.

[0038] In a preferred embodiment, the amide group content in the activation layer is 5-20 mmol / m², based on the surface area of ​​the dry-based filler per square meter. 2 The content of carboxylic acid groups and sulfonic acid groups is 15-80 mmol / m. 2 The content of phenolic hydroxyl and sulfone groups is 2-62 mmol / m 2 Preferably, in the activated layer, the content of amide groups is 10-20 mmol / m² per square meter of dry base filler surface area. 2 The content of carboxylic acid groups and sulfonic acid groups is 20-80 mmol / m 2The content of phenolic hydroxyl and sulfone groups is 6-62 mmol / m 2 .

[0039] In a preferred embodiment, the activated layer contains 35-50 mmol / m² of phenolic hydroxyl groups, based on the surface area of ​​the dry-based filler per square meter. 2 The sulfone content is 2-12 mmol / m 2 More preferably, in the activated layer, based on the surface area of ​​the dry-based filler per square meter, the content of phenolic hydroxyl groups is 40-50 mmol / m². 2 The sulfone content is 6-12 mmol / m 2 .

[0040] In a preferred embodiment, the activated layer contains 15-30 mmol / m² of carboxylic acid groups, based on the surface area of ​​the dry-based filler per square meter. 2 The content of sulfonic acid groups is 20-50 mmol / m 2 More preferably, in the activated layer, based on the surface area of ​​the dry-based filler per square meter, the content of carboxylic acid groups is 20-30 mmol / m². 2 The content of sulfonic acid groups is 30-50 mmol / m 2 .

[0041] In this invention, by controlling the content of each group in the activation layer, it has the advantages of suitable hydrolysis catalytic activity and promoting the shift of hydrolysis equilibrium.

[0042] In a preferred embodiment, the thickness of the activation layer is 25-47 micrometers. In this invention, the thickness of the activation layer is measured using an X-ray fluorescence thickness gauge.

[0043] A second aspect of the present invention provides a method for preparing a modified hydrolytic filler, wherein the method comprises:

[0044] (1) The packing is subjected to silanization treatment to obtain a packing coated with a silane layer;

[0045] (2) The filler coated with silane layer is activated at least once using an activating component to obtain a modified hydrolytic filler;

[0046] The activated component contains amide groups, phenolic hydroxyl groups, sulfone groups, carboxylic acid groups, and sulfonic acid groups.

[0047] In this invention, the type and specific surface area of ​​the filler in step (1) have been described in the first aspect and will not be repeated here.

[0048] In this invention, the filler can be pretreated before silanization. Specifically, the filler is first ultrasonically polished with a suspension polishing slurry (preferably silicon carbide) (the ultrasonic frequency is preferably 20-40 kHz), then ultrasonically cleaned (preferably, the filler is ultrasonically cleaned sequentially with demineralized water (ultrasonic frequency 30-70 kHz, temperature 60-80°C, cleaning time 30-40 minutes), ultrasonically cleaned with acetone (ultrasonic frequency 40-80 kHz, temperature 20-40°C, cleaning time 20-30 minutes), and ultrasonically cleaned with alkaline solution (the alkaline solution composition, by mass content, is 8-12% sodium hydroxide and 0.6-1.2% sodium phosphate, ultrasonic frequency 50-90 kHz, alkaline washing temperature 60-90°C, alkaline washing time 20-30 minutes)). It is then rinsed with water (preferably demineralized water) (preferably 4-6 times), and finally dried with nitrogen gas (preferably at 20-40°C).

[0049] In a preferred embodiment, in step (1), the thickness of the silane layer is 2-6 micrometers.

[0050] In a preferred embodiment, the silanization process includes contacting a solution containing a silane reagent with the filler, followed by drying and curing. The method of silanization is not particularly limited in this invention; for example, a dip-coating method conventionally defined in the art can be selected.

[0051] In this invention, the selection range of conditions for silanization treatment is relatively wide. Preferably, in step (1), the conditions for silanization treatment include: immersion coating time of 1-4 min, drying and curing temperature of 110-130℃, and drying and curing time of 30-50 min.

[0052] In a preferred embodiment, in step (1), the solution containing the silane reagent is obtained by mixing the silane reagent, water and anhydrous low alcohol, and then performing pre-hydrolysis.

[0053] In this invention, the selection range for pre-hydrolysis conditions is relatively wide. Preferably, the pre-hydrolysis time is 10-25 hours.

[0054] In a preferred embodiment, the volume ratio of silane reagent: water: anhydrous low alcohol is (2.8-5.2):(4-7):(90-95).

[0055] In a preferred embodiment, the pH value of the silane-containing reagent solution is 7.5-8.5.

[0056] In a preferred embodiment, the anhydrous low-carbon alcohol is anhydrous methanol and / or anhydrous ethanol, preferably anhydrous ethanol.

[0057] In a preferred embodiment, the silane reagent is selected from at least one of 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl methacrylate, 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl acrylate, and 3-(isobutenoyloxy)propyltrimethoxysilane.

[0058] In a preferred embodiment, the anhydrous low-carbon alcohol is anhydrous methanol and / or anhydrous ethanol.

[0059] In a preferred embodiment, in step (1), the amount of the silane-containing reagent solution is such that the molar ratio of the group (-Si-O-Si-) to the group (-Si-OM) in the prepared filler coated with the silane layer is 1.3-4.2, wherein M is a metal from the filler.

[0060] In a preferred embodiment, in step (2), the activation treatment causes the outer surface of the filler coated with the silane layer to be coated with an activation layer, the activation layer comprising amide groups, phenolic hydroxyl groups and sulfone groups, carboxylic acid groups and sulfonic acid groups.

[0061] In this invention, the types and contents of each group in the activation layer and their preferred range have been described in the first aspect, and will not be repeated here.

[0062] In a preferred embodiment, the activation treatment is performed 1-5 times. It is understood that, through repeated activation treatments, the resulting activated layer has the structure of activated layer A and activated layer B, or activated layer A and activated layer B, to meet usage requirements.

[0063] In a preferred embodiment, the amide group is provided by an amide derivative, preferably by at least one of N,N'-[ethylenedi(oxymethylene)]bis(acrylamide), N,N'-(1,2-dihydroxyethylene)disacrylamide and hexamethylenebisacrylamide.

[0064] In a preferred embodiment, the phenolic hydroxyl group is provided by a phenolic derivative, preferably at least one of 2,2'-diallylbisphenol A, 3,3'-diallyldiethylhexestrol, 4,4'-methylenebis[2-allylphenol], and 5-[(1R)-1-(4-hydroxyphenyl)-2-propen-1-yl]-2,3,4-trimethoxyphenol.

[0065] In a preferred embodiment, the sulfone group is provided by a sulfone derivative, preferably 1,1'-sulfone-bis[4-(2-propenyl)oxybenzene] and / or 3-butenyl-p-tolyl sulfone, 4-chlorophenyl(vinyl) sulfone.

[0066] In a preferred embodiment, the carboxylic acid group is provided by a carboxylic acid derivative, preferably at least one of 1-methyl-3-(4-methyl-3-pentenyl)cyclohex-3-en-1-carboxylic acid, 2-carboxy-1-cyclopenten-1-acetic acid, 4,4-stilbene dicarboxylic acid, and bicyclo[2.2.2]-5-octene-2,3-dicarboxylic acid.

[0067] In a preferred embodiment, the sulfonic acid group is provided by a sulfonic acid derivative, preferably by at least one of 4-{(E)-2-[3,5-di(sulfonoxy)phenyl]vinyl}phenyl hydrogen sulfate, 2-hydroxy-3-(methacryloyloxy)-1-propane sulfonic acid, (Z)-4',4”'-(ethylene-1,2-diyl)bis(([[1,1'-biphenyl]-4-sulfonic acid)), poly(2-acrylamido-2-methyl-1-propane sulfonic acid), and 4-hydroxy-6-(prop-2-enoylamino)naphthalene-2-sulfonic acid.

[0068] In a preferred embodiment, step (2) includes a first activation treatment and a second activation treatment performed sequentially; the first activation treatment includes contacting a solution containing a first activation component with a filler coated with a silane layer; the second activation treatment includes contacting a solution containing a second activation component with the product obtained from the first activation treatment; the first activation component contains amide groups, phenolic hydroxyl groups, and sulfone groups, and the second activation component contains carboxylic acid groups and sulfonic acid groups. In this invention, the first activation treatment forms an activation layer A, and the second activation treatment forms an activation layer B.

[0069] In this invention, preferably, step (2) involves at least one first activation treatment and at least one second activation treatment. This means that in this invention, the first and second activation treatments are performed alternately, resulting in the formation of activation layer A and activation layer B, or activation layer A and activation layer B structures in the activation layer. The specific number of activations can be determined according to actual needs.

[0070] In a preferred embodiment, in step (2), the mass ratio of the first activating component to the first initiator to the first solvent in the solution containing the first activating component is (13-26):(1-2):(220-280).

[0071] In this invention, the type of the first initiator is not particularly limited and can be any initiator conventionally defined in the art. Preferably, the first initiator is selected from at least one of azo, organic peroxide, inorganic peroxide, and redox initiators, more preferably at least one of azobisisobutyronitrile, benzoyl peroxide, potassium persulfate, and hydrogen peroxide, and even more preferably benzoyl peroxide.

[0072] In this invention, there is no particular limitation on the type of the first solvent. Preferably, the first solvent is selected from at least one of toluene, p-xylene, m-xylene, and o-xylene.

[0073] In a preferred embodiment, the first activating component includes amide derivatives, phenolic derivatives, and sulfone derivatives.

[0074] In a preferred embodiment, the molar ratio of amide group: phenolic hydroxyl group: sulfone group in the first activating component is (0.2-10):(3-20):1.

[0075] In a preferred embodiment, in step (2), the first activation treatment conditions include: the liquid-to-solid volume ratio of the solution containing the first activation component to the filler coated with the silane layer in step (1) is 2-6, the immersion temperature is 52-73°C, and the time is 1-3 hours.

[0076] In a preferred embodiment, in step (2), the mass ratio of the second activating component to the second initiator to the second solvent in the solution containing the second activating component is (13-28):(0.8-2.3):(230-280).

[0077] In this invention, the range of types of the second initiator can be the same as that of the first initiator, and will not be elaborated further here.

[0078] In this invention, the range of types of the second solvent can be the same as that of the first solvent, and will not be elaborated further here.

[0079] In a preferred embodiment, the second activating component includes carboxylic acid derivatives and sulfonic acid derivatives.

[0080] In a preferred embodiment, the molar ratio of sulfonic acid group to carboxylic acid group in the second activating component is (0.75-3.5):1.

[0081] In a preferred embodiment, in step (2), the second activation treatment conditions include: the liquid-to-solid volume ratio of the solution containing the second activation component to the product obtained from the first activation treatment is 2-6, the soaking temperature is 53-72°C, and the soaking time is 1-3 hours.

[0082] In a preferred embodiment, in step (2), the activation treatment is followed by immersion in a post-treatment agent. The advantage of this preferred embodiment is that it removes free modified components from the activated layer, facilitating mass transfer.

[0083] In this invention, there is no particular limitation on the type of post-treatment agent. Preferably, the post-treatment agent is selected from at least one of toluene, p-xylene, m-xylene, and o-xylene.

[0084] In this invention, the selection range for post-soaking treatment conditions is relatively wide. Preferably, the post-soaking treatment conditions include a soaking time of 30-300 minutes.

[0085] In a preferred embodiment, step (2) further includes: pretreatment in a pretreatment agent followed by drying under a protective atmosphere to obtain modified hydrolyzed filler.

[0086] In a preferred embodiment, the pretreatment agent is anhydrous low-carbon alcohol, preferably anhydrous ethanol and / or anhydrous methanol.

[0087] In a preferred embodiment, the protective atmosphere is nitrogen and / or an inert atmosphere, preferably nitrogen.

[0088] In a preferred embodiment, the pretreatment conditions include: soaking time of 30-300 min, drying temperature of 110-130℃, and drying time of 10-30 min.

[0089] The third aspect of this invention provides the application of the modified hydrolysis filler described in the first aspect or the modified hydrolysis filler prepared by the preparation method described in the second aspect in the hydrolysis of aldehyde fatty acid esters.

[0090] A fourth aspect of this invention provides a method for preparing an aqueous formaldehyde-formic acid solution, wherein the method includes contacting the modified hydrolyzing filler described in the first aspect or the modified hydrolyzing filler obtained by the preparation method described in the second aspect with formaldehyde-formic acid ester to carry out a hydrolysis reaction. Specifically, the aqueous formaldehyde-formic acid ester solution is contacted with the modified hydrolyzing filler to obtain the aqueous formaldehyde-formic acid ester solution.

[0091] In this invention, the selection range for the formaldehyde formate ester is relatively wide. Preferably, the formaldehyde formate ester can be obtained by at least one of the following methods: formaldehyde formate ester oxidation, dimethyl maleate ozone oxidation, dimethyl tartrate periodic acid oxidation, alkyl exchange of dimethoxyglyoxylate with glyoxylic acid monohydrate, and acrylate peroxide oxidation.

[0092] In a preferred embodiment, the contact is carried out in a fixed-bed reactor and / or a reactive distillation column, preferably in a combination of a fixed-bed reactor and a reactive distillation column, specifically, the fixed-bed reactor and the reactive distillation column are used in series.

[0093] In a preferred embodiment, the reaction temperature in the fixed-bed reactor is 50-90°C, and the reaction volume hourly space velocity is 1-3 h⁻¹. -1 The water-ester molar ratio is 5-20.

[0094] In a preferred embodiment, the reactive distillation column has a theoretical plate number of 3-10, a reflux ratio of 0.5-3, a pressure of 10-80 kPa (absolute pressure gauge), and a water-ester molar ratio of 3-20.

[0095] In a preferred embodiment, the hydrolysis conversion rate of the formaldehyde formate ester is ≥99%, and the oligomer content in the formaldehyde formic acid aqueous solution is not higher than 3%, preferably not higher than 1.5%.

[0096] In this invention, the oligomer is a dimer or higher polymer of formaldehyde formic acid, and its content is determined by liquid chromatography.

[0097] In this invention, by overlapping activation layer A and activation layer B, an activation layer of suitable thickness with a "sandwich" structure is formed, which can ensure the effective combination of "water-rich", "catalysis" and "diffusion", avoid excessive thickness, and enable formaldehyde ester, formaldehyde formic acid and water to have good diffusion effect.

[0098] The present invention will now be described in detail through examples and comparative examples.

[0099] In this invention, the specific surface area of ​​the packing refers to the surface area of ​​a unit volume of packing.

[0100] In this invention, the content of each group in the activated layer of the modified hydrolyzed filler is determined by the test method described above.

[0101] In this invention, component analysis employed a 20A high-performance liquid chromatography (HPLC) system (Shimadzu Corporation, Japan, equipped with an autosampler, 10AT and 10AD pumps, and a 20A multi-wavelength UV detector); and an ACQUITY UPLC / Xevo G2 QTOF ultra-high performance liquid chromatography-high resolution tandem mass spectrometry (Waters Corporation, USA, equipped with an autosampler and a diode array UV detector). HPLC conditions were as follows: column: Zorbax Eclipse Plus C18 (4.6 mm × 150 mm, 5 μm); mobile phase: water (containing 0.06% v phosphoric acid): acetonitrile = 95:5; flow rate: 1.0 mL / min; detection wavelength: 210 nm; column temperature: 35 °C; injection volume: 1 μL. Ultra-high performance liquid chromatography (UHPLC) conditions: Column: HSS T3 (2.1 mm × 100 mm, 1.7 μm); Mobile phase: water, methanol; Gradient elution (positive ion mode): 0 min V(water):V(methanol) = 85:15, after 2.5 min V(water):V(methanol) = 55:35, after 4 min V(water):V(methanol) = 10:90, flow rate: 0.45 mL / min; Gradient elution (negative ion mode): 0 min V(water):V(methanol) = 70:30, after 2.5 min V(water):V(methanol) = 55:35, after 3.5 min V(water):V(methanol) = 10:90; flow rate: 0.45 mL / min; Column temperature: 30 ℃; Injection volume: 3 μL. Mass spectrometry conditions: electrospray ionization source (ESI), positive or negative ion scanning mode, capillary voltage 2kV, cone voltage 30eV, ion source temperature: 120℃, desolventizing temperature 450℃, cone gas flow rate 50L / h, desolventizing gas (N2) flow rate 900L / h.

[0102] The formula for calculating the hydrolysis conversion rate of formaldehyde esters is:

[0103] Hydrolysis conversion rate (%) = (1 - Amount of residual raw material after hydrolysis / Total amount of raw material) × 100%

[0104] Example 1

[0105] The formaldehyde ester described in this embodiment is derived from the formaldehyde ester oxidation method, and the water-ester molar ratio in the hydrolysis raw material is 9:1.

[0106] The method for preparing the modified hydrolyzed filler described in this embodiment includes: (1) silanizing the filler to obtain a filler coated with a silane layer; (2) performing a first activation treatment and a second activation treatment on the filler coated with a silane layer obtained in step (1), and repeating step (2) to obtain the hydrolyzed filler.

[0107] The packing material described in step (1) is a corrugated wire mesh structured packing with a specific surface area of ​​1550 m². 2 / m3 The material is 304 stainless steel. The silanization treatment adopts the conventional dip-coating method in the art. Before the silanization treatment, the filler is first pretreated. Specifically, the filler is first ultrasonically polished with a suspension polishing slurry (silicon carbide) at a polishing ultrasonic frequency of 30 kHz. Then, it is sequentially ultrasonically cleaned with desalinated water (cleaning ultrasonic frequency of 50 kHz, temperature of 70 ℃, cleaning time of 35 minutes), ultrasonically cleaned with acetone (cleaning ultrasonic frequency of 60 kHz, cleaning temperature of 30 ℃, cleaning time of 25 minutes), ultrasonically cleaned with alkaline solution (the alkaline solution composition, by mass content, is 10% sodium hydroxide and 0.9% sodium phosphate, ultrasonic frequency of 75 kHz, alkaline washing temperature of 75 ℃, alkaline washing time of 25 minutes), rinsed with desalinated water (5 times), and dried with nitrogen gas (temperature of 30 ℃). Subsequently, the silane layer was dip-coated (immersion time was 2.5 minutes) in a silane reagent solution (selected from 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl methacrylate) (the composition of the silane reagent solution, by volume, was silane reagent:deionized water:anhydrous ethanol = 4.1:5.5:92, pH value was 8.1, and the silane reagent solution was prepared by mixing the silane reagent, deionized water and anhydrous ethanol according to the ratio and pre-hydrolyzing for 17 hours). After drying and curing, a silane layer with a molar ratio of (-Si-O-Si-) to (-Si-OM) groups of 2.8 and a thickness of 4.2 micrometers was obtained. The drying and curing temperature was 120°C, the drying time was 40 minutes, and the drying atmosphere was nitrogen.

[0108] The filler after silanization in step (1) is sequentially subjected to the first activation treatment, the second activation treatment, the first activation repetition treatment, and the second activation repetition treatment in step (2) to obtain an activated layer. The solution containing the first activation component used in the first activation layer includes the first activation component (the first activation component includes amide derivatives, phenolic derivatives, and sulfone derivatives, wherein the amide derivatives are selected from N,N′-(1,2-dihydroxyethylene)acrylamide, the phenolic derivatives are selected from 3,3'-diallyldiethylhexylestradiol, and the sulfone derivatives are selected from 3-butenyl-p-tolyl sulfone), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The first activation component, benzoyl peroxide, and solvent, by mass parts, are: first activation component: benzoyl peroxide: solvent = 19.5: 1.5: 255. Wherein, the amide derivatives, phenolic derivatives, and sulfone derivatives, by molar ratio, are: amide group: phenolic hydroxyl group: sulfone group = 5.3: 11.6: 1. The conditions for the first activation treatment are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the first activation component to the filler coated with silane layer obtained in step (1) is 4, the immersion treatment temperature is 63°C, and the immersion treatment time is 2 hours.

[0109] The product after the first activation treatment is further subjected to a first post-activation treatment to obtain a first post-activation treated product. The first post-activation treatment agent used is p-xylene. The first post-activation treatment is performed by immersion for 60 minutes.

[0110] The obtained wet-based filler (the product after the first activation treatment) is subjected to a second activation treatment to obtain a second activated product. The solution containing the second activation component is the second activation component (the second activation component includes carboxylic acid derivatives and sulfonic acid derivatives, wherein the carboxylic acid derivatives are selected from 1-methyl-3-(4-methyl-3-pentenyl)cyclohex-3-en-1-carboxylic acid, and the sulfonic acid derivatives are selected from 2-hydroxy-3-(methacryloyloxy)-1-propanesulfonic acid), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The second activation component, benzoyl peroxide, and solvent, by mass parts, are: second activation component: benzoyl peroxide: solvent = 20.3:1.6:258. Among them, the sulfonic acid derivatives and carboxylic acid derivatives, by molar ratio, are: sulfonic acid group: carboxylic acid group = 2.2:1. The treatment conditions for the second activation treatment are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the second activation component to the product obtained in step (2) is 4, the treatment temperature is 63°C, and the treatment time is 2 hours.

[0111] The product after the second activation treatment was subjected to a second post-activation treatment to obtain the product after the second activation treatment. The activating agent used in the second post-activation treatment was p-xylene. The second post-activation treatment was carried out by immersion for 60 minutes.

[0112] The wet-based packing material (the product of the second activation treatment) was subjected to one repeated first activation treatment and one repeated second activation treatment to obtain a repeatedly activated product. The repeatedly activated product underwent pretreatment to obtain a modified hydrolyzed packing material. Anhydrous ethanol was used as the pretreatment agent. The pretreatment method was immersion for 60 minutes. After pretreatment, the material was dried in nitrogen at 120°C for 20 minutes. In the obtained modified hydrolyzed packing material, the amide group content in the activated layer was 12.7 mmol / m³. 2 The content of carboxylic acid groups is 22.6 mmol / m 2 The content of sulfonic acid groups is 35.2 mmol / m 2 The content of phenolic hydroxyl groups was 42.6 mmol / m 2 The sulfone content is 6.9 mmol / m 2 The thickness of the activation layer is 36.3 micrometers.

[0113] The application of the modified hydrolysis packing material prepared in Example 1 in the hydrolysis of formaldehyde formate includes: contacting an aqueous solution of formaldehyde formate with the modified hydrolysis packing material to obtain an aqueous solution of formaldehyde formic acid. The application employs a combination of a fixed-bed reactor and a reactive distillation column, wherein the fixed-bed reactor is connected in series before the reactive distillation column. The fixed-bed reactor operates at a reaction temperature of 70°C and a reaction volume hourly space velocity (VHSV) of 2 h⁻¹. -1 The reactive distillation column has a theoretical plate number of 6, a reflux ratio of 1.8, and an operating pressure (absolute pressure) of 40 kPa.

[0114] In Example 1, the hydrolysis conversion rate of formaldehyde formate was 99.4%, and the oligomer content in the aqueous solution of the obtained formaldehyde formic acid product was 1.2%.

[0115] Example 2

[0116] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0117] According to the method of Example 1, the packing material in step (1) is a corrugated wire mesh structured packing material with a specific surface area of ​​2200 m². 2 / m 3 The material is 304 stainless steel. The silanization treatment adopts the conventional dip-coating method in the art. Before the silanization treatment, the filler is first pretreated. Specifically, the filler is first ultrasonically polished with a suspension polishing slurry (silicon carbide) at a polishing ultrasonic frequency of 38 kHz. Then, it is ultrasonically cleaned with desalinated water (cleaning ultrasonic frequency of 67 kHz, temperature of 79 ℃, cleaning time of 38 minutes), ultrasonically cleaned with acetone (cleaning ultrasonic frequency of 75 kHz, cleaning temperature of 37 ℃, cleaning time of 28 minutes), ultrasonically cleaned with alkaline solution (the alkaline solution composition, by mass content, is 11.2% sodium hydroxide and 1.1% sodium phosphate, ultrasonic frequency of 88 kHz, alkaline washing temperature of 87 ℃, alkaline washing time of 29 minutes), rinsed with desalinated water (6 times), and dried with nitrogen gas (temperature of 37 ℃). Subsequently, the silane layer was dip-coated (3.5 minutes) in a silane reagent solution (selected from 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl methacrylate) (the composition of the silane reagent solution, by volume, is silane reagent:deionized water:anhydrous ethanol = 4.9:6.6:94, pH value is 7.6, and the silane reagent solution is prepared by mixing the silane reagent, deionized water and anhydrous ethanol according to the ratio and pre-hydrolyzing for 24 hours). After drying and curing, a silane layer with a molar ratio of (-Si-O-Si-) to (-Si-OM) groups of 3.9 and a thickness of 5.7 micrometers was obtained. The drying and curing temperature was 112°C, the drying time was 32 minutes, and the drying atmosphere was nitrogen.

[0118] The filler after silanization in step (1) is sequentially subjected to the first activation treatment, the second activation treatment, the first activation repetition treatment, and the second activation repetition treatment in step (2) to obtain an activated layer. The solution containing the first activation component used in the first activation layer includes the first activation component (the first activation component includes amide derivatives, phenolic derivatives, and sulfone derivatives, wherein the amide derivatives are selected from N,N′-(1,2-dihydroxyethylene)acrylamide, the phenolic derivatives are selected from 3,3'-diallyldiethylhexylestradiol, and the sulfone derivatives are selected from 3-butenyl-p-tolyl sulfone), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The first activation component, benzoyl peroxide, and solvent, by mass parts, are: first activation component: benzoyl peroxide: solvent = 24.7:1.8:236. The amide derivatives, phenolic derivatives, and sulfone derivatives, by molar ratio, are: amide group: phenolic hydroxyl group: sulfone group = 8.7:18.5:1. The conditions for the first activation treatment are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the first activation component to the filler coated with silane layer obtained in step (1) is 6, the soaking temperature is 71°C, and the soaking time is 2.7 hours.

[0119] The product after the first activation treatment is further subjected to a first post-activation treatment to obtain a first post-activation treated product. The first post-activation treatment agent used is p-xylene. The first post-activation treatment is performed by immersion for 100 minutes.

[0120] The obtained wet-based filler (the product after the first activation treatment) is subjected to a second activation treatment to obtain a second activated product. The solution containing the second activation component is the second activation component (the second activation component includes carboxylic acid derivatives and sulfonic acid derivatives, wherein the carboxylic acid derivatives are selected from 1-methyl-3-(4-methyl-3-pentenyl)cyclohex-3-en-1-carboxylic acid, and the sulfonic acid derivatives are selected from 2-hydroxy-3-(methacryloyloxy)-1-propanesulfonic acid), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The second activation component, benzoyl peroxide, and solvent, by mass parts, are: second activation component: benzoyl peroxide: solvent = 26.9: 2.1: 243. Among them, the sulfonic acid derivatives and carboxylic acid derivatives, by molar ratio, are: sulfonic acid group: carboxylic acid group = 3.2: 1. The treatment conditions for the second activation treatment are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the second activation component to the product obtained in step (2) is 6, the treatment temperature is 68°C, and the treatment time is 2.5 hours.

[0121] The product after the second activation treatment was subjected to a second post-activation treatment to obtain the product after the second activation treatment. The activating agent used in the second post-activation treatment was p-xylene. The second post-activation treatment was carried out by immersion for 100 minutes.

[0122] Wet-based packing material (the product of the second activation treatment) underwent one first activation repeat treatment and one second activation repeat treatment to obtain a repeatedly activated product. This repeatedly activated product underwent pretreatment to obtain modified hydrolyzed packing material. Anhydrous ethanol was used as the pretreatment agent. The pretreatment method was immersion for 100 minutes. After pretreatment, the material was dried in nitrogen at 113°C for 14 minutes. In the obtained modified hydrolyzed packing material, the amide group content in the activated layer was 17.9 mmol / m³. 2 The carboxylic acid group content is 28.4 mmol / m 2 The sulfonic acid content is 47.5 mmol / m 2 The content of phenolic hydroxyl groups was 49.1 mmol / m 2 The sulfone group has a concentration of 10.3 mmol / m³. 2 The thickness of the activation layer is 45.6 micrometers.

[0123] The reaction method of Example 1 was followed, wherein a fixed-bed reactor was used, the reaction temperature was 60°C, and the reaction volume hourly space velocity was 1.1 h⁻¹. -1 The reactive distillation column has a theoretical plate number of 4, a reflux ratio of 0.7, and an operating pressure (absolute pressure) of 27 kPa.

[0124] In Example 2, the hydrolysis conversion rate of formaldehyde formate was 99.6%, and the oligomer content in the resulting aqueous formaldehyde formate product was 0.8%.

[0125] Example 3

[0126] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0127] According to the method of Example 1, the packing material in step (1) is a corrugated wire mesh structured packing material with a specific surface area of ​​1000 m². 2 / m 3The material is 304 stainless steel. The silanization treatment adopts the conventional dip-coating method in the art. Before the silanization treatment, the filler is first pretreated. Specifically, the filler is first ultrasonically polished with a suspension polishing slurry (silicon carbide) at a polishing ultrasonic frequency of 22 kHz. Then, it is ultrasonically cleaned with desalinated water (cleaning ultrasonic frequency of 31 kHz, temperature of 62 ℃, cleaning time of 32 minutes), ultrasonically cleaned with acetone (cleaning ultrasonic frequency of 43 kHz, cleaning temperature of 22 ℃, cleaning time of 21 minutes), ultrasonically cleaned with alkaline solution (the alkaline solution composition, by mass content, is 8.5% sodium hydroxide and 0.7% sodium phosphate, ultrasonic frequency of 53 kHz, alkaline washing temperature of 63 ℃, alkaline washing time of 23 minutes), rinsed with desalinated water (4 times), and dried with nitrogen gas (temperature of 23 ℃). Subsequently, the silane layer was dip-coated (immersion time was 1.4 minutes) in a silane reagent solution (selected from 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl methacrylate) (the composition of the silane reagent solution, by volume, was silane reagent:deionized water:anhydrous ethanol = 3.1:4.3:91, pH value was 8.3, and the silane reagent solution was prepared by mixing the silane reagent, deionized water and anhydrous ethanol according to the ratio and pre-hydrolyzing for 12 hours). After drying and curing, a silane layer with a molar ratio of (-Si-O-Si-) to (-Si-OM) groups of 1.8 and a thickness of 2.9 micrometers was obtained. The drying and curing temperature was 128°C, the drying time was 48 minutes, and the drying atmosphere was nitrogen.

[0128] The filler after silanization in step (1) is sequentially subjected to the first activation treatment, the second activation treatment, the first activation repetition treatment, and the second activation repetition treatment in step (2) to obtain an activated layer. The solution containing the first activation component used in the first activation layer includes the first activation component (the first activation component includes amide derivatives, phenolic derivatives, and sulfone derivatives, wherein the amide derivatives are selected from N,N′-(1,2-dihydroxyethylene)acrylamide, the phenolic derivatives are selected from 3,3'-diallyldiethylhexylestradiol, and the sulfone derivatives are selected from 3-butenyl-p-tolyl sulfone), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The first activation component, benzoyl peroxide, and solvent, by mass parts, are: first activation component: benzoyl peroxide: solvent = 15.3:1.1:267. Wherein, the amide derivatives, phenolic derivatives, and sulfone derivatives, by molar ratio, are: amide group: phenolic hydroxyl group: sulfone group = 3.6:6.8:1. The conditions for the first activation treatment are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the first activation component to the filler coated with silane layer obtained in step (1) is 2, the immersion treatment temperature is 58°C, and the immersion treatment time is 1.4 hours.

[0129] The filler material after the first activation treatment is then subjected to a first post-activation treatment to obtain the first post-activation product. The first post-activation agent used in the first post-activation treatment is p-xylene. The first post-activation treatment is performed by immersion for 40 minutes.

[0130] The obtained wet-based filler (the product after the first activation treatment) is subjected to a second activation treatment to obtain a second activated product. The solution containing the second activation component is the second activation component (the second activation component includes acid derivatives, sulfonic acid derivatives, wherein the carboxylic acid derivatives are selected from 1-methyl-3-(4-methyl-3-pentenyl)cyclohex-3-en-1-carboxylic acid, and the sulfonic acid derivatives are selected from 2-hydroxy-3-(methacryloyloxy)-1-propanesulfonic acid), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The second activation component, benzoyl peroxide, and solvent, by mass parts, are: second activation component: benzoyl peroxide: solvent = 15.7: 1.2: 265. Among them, the sulfonic acid derivatives and carboxylic acid derivatives, by molar ratio, are: sulfonic acid group: carboxylic acid group = 2.1: 1. The treatment conditions for the second activation treatment are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the second activation component to the product obtained in step (2) is 2, the treatment temperature is 57°C, and the treatment time is 1.3 hours.

[0131] The product after the second activation treatment was subjected to a second post-activation treatment to obtain the product after the second activation treatment. The activating agent used in the second post-activation treatment was p-xylene. The second post-activation treatment was carried out by immersion for 40 minutes.

[0132] Wet-based packing material (the product of the second activation treatment) underwent one first activation repeat treatment and one second activation repeat treatment to obtain a repeatedly activated product. This repeatedly activated product underwent pretreatment to obtain hydrolyzed packing material. Anhydrous ethanol was used as the pretreatment agent. The pretreatment method was immersion for 40 minutes. After pretreatment, the material was dried in nitrogen at 128°C for 25 minutes. In the resulting hydrolyzed packing material, the amide group content in the activated layer was 8.7 mmol / m³. 2 The content of carboxylic acid groups is 17.9 mmol / m 2 The content of sulfonic acid groups is 23.2 mmol / m 2 The content of phenolic hydroxyl groups was 36.5 mmol / m 2 The sulfone content is 4.5 mmol / m 2 The thickness of the activation layer is 28.3 micrometers.

[0133] The reaction method in Example 1 was followed, wherein a fixed-bed reactor was used, the reaction temperature was 80°C, and the reaction volume hourly space velocity was 2.6 h⁻¹. -1The reactive distillation column has a theoretical plate number of 8, a reflux ratio of 2.7, and an operating pressure (absolute pressure) of 57 kPa.

[0134] In Example 3, the hydrolysis conversion rate of formaldehyde formate was 99.3%, and the oligomer content in the aqueous solution of the obtained formaldehyde formate product was 1.9%.

[0135] Example 4

[0136] The method is the same as in Example 2, except that the water-ester molar ratio in the hydrolyzed feedstock is 7.5:1.

[0137] In Example 4, the hydrolysis conversion rate of formaldehyde formate was 99.52%, and the oligomer content in the aqueous solution of the obtained formaldehyde formate product was 0.89%.

[0138] Example 5

[0139] The method is the same as in Example 2, except that the water-ester molar ratio in the hydrolyzed raw material is 6:1.

[0140] In Example 5, the hydrolysis conversion rate of formaldehyde formate was 99.48%, and the oligomer content in the aqueous solution of the obtained formaldehyde formic acid product was 0.94%.

[0141] Example 6

[0142] The method is the same as in Example 2, except that the water-ester molar ratio in the hydrolyzed raw material is 13:1.

[0143] In Example 6, the hydrolysis conversion rate of formaldehyde formate was 99.68%, and the oligomer content in the aqueous solution of the obtained formaldehyde formate product was 0.45%.

[0144] Example 7

[0145] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0146] The method is the same as in Example 3, except that no post-immersion treatment is performed after the first and second activation treatments.

[0147] In the obtained modified hydrolyzed filler, the content of amide groups in the activated layer is 8.6 mmol / m. 2 The content of carboxylic acid groups is 17.7 mmol / m 2 The content of sulfonic acid groups is 23.1 mmol / m 2 The content of phenolic hydroxyl groups was 36.2 mmol / m. 2 The sulfone content is 4.4 mmol / m 2 The thickness of the activation layer is 28.1 micrometers.

[0148] Following the reaction method of Example 3, the hydrolysis conversion rate of formaldehyde formate in Example 7 was 99.2%, and the oligomer content in the aqueous solution of the obtained formaldehyde formate product was 1.95%.

[0149] Example 8

[0150] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0151] The method is the same as in Example 3, except that the activation treatment in step (2) is performed using a one-pot method.

[0152] The filler after silanization in step (1) is sequentially subjected to the first and second activation treatments in step (2), and the first and second activation treatments are repeated to obtain an activated layer. The solutions containing the first and second activation components used in the first and second activation layers are prepared by mixing equal volumes of the first activation component solution and the second activation component solution. The first activation component solution includes a first activation component (the first activation component includes amide derivatives, phenolic derivatives and sulfone derivatives, wherein the amide derivatives are selected from N,N′-(1,2-dihydroxyethylene)acrylamide, the phenolic derivatives are selected from 3,3'-diallyldiethylhexylestradiol, and the sulfone derivatives are selected from 3-butenyl-p-tolyl sulfone), benzoyl peroxide and a solvent; the solvent is selected from toluene. The first activation component, benzoyl peroxide and solvent, by mass parts, are: first activation component: benzoyl peroxide: solvent = 15.3:1.1:267. Wherein, the amide derivatives, phenolic derivatives and sulfone derivatives, by molar ratio, are: amide group: phenolic hydroxyl group: sulfone group = 3.6:6.8:1. The second activation component solution includes a second activation component (the second activation component includes acid derivatives, sulfonic acid derivatives, wherein the carboxylic acid derivatives are selected from 1-methyl-3-(4-methyl-3-pentenyl)cyclohex-3-en-1-carboxylic acid, and the sulfonic acid derivatives are selected from 2-hydroxy-3-(methacryloyloxy)-1-propanesulfonic acid), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The second activation component, benzoyl peroxide, and solvent, by mass parts, are: second activation component: benzoyl peroxide: solvent = 15.7: 1.2: 265. Among them, the sulfonic acid derivatives and carboxylic acid derivatives, by molar ratio, are: sulfonic acid group: carboxylic acid group = 2.1: 1. The treatment conditions for the first and second activation treatments are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the first and second activation components to the filler coated with the silane layer obtained in step (1) is 2, the immersion treatment temperature is 58°C, and the immersion treatment time is 1.3 hours.

[0153] The filler material after the first and second activation treatments was further processed into first and second post-activation products. The first and second post-activation agents used in these treatments were p-xylene. The first and second post-activation treatments were performed by immersion for 40 minutes.

[0154] Wet-based packing material (products of the first / second activation treatment) underwent repeated first / second activation treatments to obtain repeatedly activated products. These repeatedly activated products were then subjected to pretreatment to obtain hydrolyzed packing material. Anhydrous ethanol was used as the pretreatment agent. Immersion was employed as the pretreatment method, with a soaking time of 40 minutes. After pretreatment, the material was dried in nitrogen at 128°C for 25 minutes. In the resulting hydrolyzed packing material, the amide group content in the activated layer was 8.3 mmol / m³. 2 The content of carboxylic acid groups is 17.1 mmol / m 2 The content of sulfonic acid groups is 22.8 mmol / m 2 The content of phenolic hydroxyl groups was 34.6 mmol / m. 2 The sulfone content is 4.3 mmol / m 2 The thickness of the activation layer is 24.5 micrometers.

[0155] Following the reaction method in Example 3, the hydrolysis conversion rate of formaldehyde formate ester in the example was 99.2%, and the oligomer content in the resulting aqueous formaldehyde formate product was 2.1%.

[0156] Comparative Example 1

[0157] The method is the same as in Example 3, except that commercially available H-type SQD67 acidic resin is used to replace the activated hydrolyzed filler.

[0158] The hydrolysis conversion rate of formaldehyde formate was 98.1%, and the oligomer content in the aqueous solution of the obtained formaldehyde formate product was 4.1%.

[0159] Comparative Example 2

[0160] The method is the same as in Example 6, except that commercially available H-type SQD67 acidic resin is used to replace the activated hydrolyzed filler.

[0161] The hydrolysis conversion rate of formaldehyde formate was 98.5%, and the oligomer content in the aqueous solution of the obtained formaldehyde formate product was 3.7%.

[0162] Comparative Example 3

[0163] The method is the same as in Example 3, except that commercially available H-type SQD67 acidic resin is used to replace the activated hydrolysis filler, and the water-ester molar ratio in the hydrolysis raw material is 25:1.

[0164] The hydrolysis conversion rate of formaldehyde formate was 99.1%, and the oligomer content in the aqueous solution of the obtained formaldehyde formate product was 2.2%.

[0165] Comparative Example 4

[0166] The method is the same as in Example 3, except that commercially available H-type SQD67 acidic resin is used to replace the activated hydrolysis filler, and the water-ester molar ratio in the hydrolysis raw material is 35:1.

[0167] The hydrolysis conversion rate of formaldehyde formate was 99.3%, and the oligomer content in the aqueous solution of the obtained formaldehyde formate product was 2.1%.

[0168] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A modified hydrolyzable filler, characterized in that, The modified hydrolysis filler comprises a silane layer and an activation layer sequentially coated on the outer surface of the filler from the inside out; the activation layer comprises amide groups, phenolic hydroxyl groups, sulfone groups, carboxylic acid groups, and sulfonic acid groups; In the activated layer, based on the surface area of ​​the dry-based filler per square meter, the content of amide groups is 5-20 mmol / m². 2 The content of carboxylic acid groups and sulfonic acid groups is 15-80 mmol / m. 2 The content of phenolic hydroxyl and sulfone groups is 2-62 mmol / m 2 .

2. The hydrolysis packing material according to claim 1, wherein, The activation layer includes at least one activation unit, the activation unit includes activation layer A and activation layer B, activation layer A includes amide groups, phenolic hydroxyl groups and sulfone groups, and activation layer B includes carboxylic acid groups and sulfonic acid groups.

3. The hydrolysis packing material according to claim 2, wherein, The activation layer A and activation layer B are sequentially coated on the surface of the silane layer.

4. The hydrolysis packing material according to any one of claims 1-3, wherein, The packing material is grid-structured packing and / or corrugated structured packing; And / or, the filler material is metal; And / or, the specific surface area of ​​the packing is 800-2300 m². 2 / m 3 .

5. The hydrolysis packing material according to claim 4, wherein, The packing material is a structured packing material made of corrugated metal wire mesh.

6. The hydrolysis packing material according to claim 4, wherein, In the silane layer, the molar ratio of the -Si-O-Si- group to the -Si-OM group is 1.3-4.2; where M is a metal derived from the filler. And / or, the thickness of the silane layer is 2-6 micrometers; And / or, the silane layer is provided with at least one of 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl methacrylate, 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl acrylate, and 3-(isobutenoyloxy)propyltrimethoxysilane.

7. The hydrolysis packing material according to any one of claims 1-3, wherein, In the activated layer, based on the surface area of ​​the dry-based filler per square meter, the content of amide groups is 10-20 mmol / m². 2 The content of carboxylic acid groups and sulfonic acid groups is 20-80 mmol / m 2 The content of phenolic hydroxyl and sulfone groups is 6-62 mmol / m 2 ; And / or, the thickness of the activation layer is 25-47 micrometers.

8. The hydrolysis packing material according to any one of claims 1-3, wherein, In the activated layer, based on the surface area of ​​the dry base filler per square meter, the content of phenolic hydroxyl groups is 35-50 mmol / m². 2 The sulfone content is 2-12 mmol / m 2 .

9. The hydrolysis packing material according to claim 8, wherein, In the activated layer, the content of phenolic hydroxyl groups is 40-50 mmol / m² per square meter of dry base filler surface area. 2 The sulfone content is 6-12 mmol / m 2 .

10. The hydrolysis packing material according to any one of claims 1-3, wherein, In the activated layer, based on the surface area of ​​the dry-based filler per square meter, the content of carboxylic acid groups is 15-30 mmol / m². 2 The content of sulfonic acid groups is 20-50 mmol / m 2 .

11. The hydrolysis packing material according to claim 10, wherein, In the activated layer, based on the surface area of ​​the dry-based filler per square meter, the content of carboxylic acid groups is 20-30 mmol / m². 2 The content of sulfonic acid groups is 30-50 mmol / m 2 .

12. A method for preparing a modified hydrolyzed filler, wherein, The method includes: (1) The packing is subjected to silanization treatment to obtain a packing coated with a silane layer; (2) The filler coated with silane layer is activated at least once using an activating component to obtain a modified hydrolyzed filler; The activating component contains amide groups, phenolic hydroxyl groups and sulfone groups, carboxylic acid groups and sulfonic acid groups; In step (2), the activation treatment causes the outer surface of the filler coated with the silane layer to be coated with an activation layer, the activation layer including amide groups, phenolic hydroxyl groups and sulfone groups, carboxylic acid groups and sulfonic acid groups; In the activated layer, based on the surface area of ​​the dry-based filler per square meter, the content of amide groups is 5-20 mmol / m². 2 The content of carboxylic acid groups and sulfonic acid groups is 15-80 mmol / m. 2 The content of phenolic hydroxyl and sulfone groups is 2-62 mmol / m 2 .

13. The method according to claim 12, wherein, In step (1), the packing material is grid-structured packing and / or corrugated structured packing; And / or, in step (1), the filler material is metal; And / or, in step (1), the specific surface area of ​​the packing is 800-2300 m². 2 / m 3 .

14. The method according to claim 13, wherein, In step (1), the filler is a structured metal corrugated wire mesh filler.

15. The method according to any one of claims 12-14, wherein, In step (1), the thickness of the silane layer is 2-6 micrometers; And / or, the silanization process includes: contacting a solution containing a silane reagent with the filler, followed by drying and curing.

16. The method according to claim 15, wherein, In step (1), the solution containing the silane reagent is obtained by mixing the silane reagent, water and anhydrous low alcohol, and then performing pre-hydrolysis.

17. The method according to claim 16, wherein, The volume ratio of silane reagent: water: anhydrous low alcohol is (2.8-5.2): (4-7): (90-95).

18. The method according to claim 16, wherein, The silane reagent is selected from at least one of 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl methacrylate, 2-hydroxy-3-[3-(trimethoxysilyl)propoxy]propyl acrylate, and 3-(isobutenoyloxy)propyltrimethoxysilane.

19. The method according to claim 15, wherein, In step (1), the amount of the silane-containing reagent solution is such that the molar ratio of the -Si-O-Si- group to the -Si-OM group in the prepared filler coated with the silane layer is 1.3-4.2, where M is a metal from the filler.

20. The method according to any one of claims 12-14, wherein, In the activated layer, the content of amide groups is 10-20 mmol / m² per square meter of dry base filler surface area. 2 The content of carboxylic acid groups and sulfonic acid groups is 20-80 mmol / m 2 The content of phenolic hydroxyl and sulfone groups is 6-62 mmol / m 2 ; And / or, the activation treatment is performed 1-5 times.

21. The method according to any one of claims 12-14, wherein, In the activated layer, the content of phenolic hydroxyl groups is 35-50 mmol / m² per square meter of dry base filler surface area. 2 The sulfone content is 2-12 mmol / m 2 .

22. The method according to claim 21, wherein, In the activated layer, the content of phenolic hydroxyl groups is 40-50 mmol / m² per square meter of dry base filler surface area. 2 The sulfone content is 6-12 mmol / m 2 .

23. The method according to any one of claims 12-14, wherein, In the activated layer, the content of carboxylic acid groups is 15-30 mmol / m² per square meter of dry base filler surface area. 2 The content of sulfonic acid groups is 20-50 mmol / m 2 .

24. The method according to claim 23, wherein, In the activated layer, the content of carboxylic acid groups is 20-30 mmol / m² per square meter of dry base filler surface area. 2 The content of sulfonic acid groups is 30-50 mmol / m 2 .

25. The method according to any one of claims 12-14, wherein, The amide group is provided by amide derivatives; And / or, the phenolic hydroxyl group is derived from phenolic derivatives; And / or, the sulfone group is provided by a sulfone derivative; And / or, the carboxylic acid group is provided by a carboxylic acid derivative; And / or, the sulfonic acid group is provided by a sulfonic acid derivative.

26. The method of claim 25, wherein, The amide group is provided by at least one of N,N'-[ethylenedi(oxymethylene)]bis(acrylamide), N,N'-(1,2-dihydroxyethylene)disacrylamide and hexamethylenebisacrylamide; And / or, the phenolic hydroxyl group is provided by at least one of 2,2'-diallylbisphenol A, 3,3'-diallyldiethylhexestrol, 4,4'-methylenebis[2-allylphenol] and 5-[(1R)-1-(4-hydroxyphenyl)-2-propen-1-yl]-2,3,4-trimethoxyphenol; And / or, the sulfone group is provided by 1,1'-sulfonebis[4-(2-propenyl)oxyphenyl] and / or 3-butenyl-p-tolyl sulfone, 4-chlorophenyl(vinyl) sulfone; And / or, the carboxylic acid group is provided by at least one of 1-methyl-3-(4-methyl-3-pentenyl)cyclohex-3-en-1-carboxylic acid, 2-carboxy-1-cyclopenten-1-acetic acid, 4,4-stilbene dicarboxylic acid and bicyclo[2.2.2]-5-octen-2,3-dicarboxylic acid; And / or, the sulfonic acid group is provided by at least one of 4-{(E)-2-[3,5-di(sulfonoxy)phenyl]vinyl}phenyl hydrogen sulfate, 2-hydroxy-3-(methacryloyloxy)-1-propanesulfonic acid, (Z)-4',4'''-(ethylene-1,2-diyl)bis(([1,1'-biphenyl]-4-sulfonic acid)), poly(2-acrylamido-2-methyl-1-propanesulfonic acid), and 4-hydroxy-6-(prop-2-enoylamino)naphthalene-2-sulfonic acid.

27. The method according to any one of claims 12-14, wherein, In step (2), the activation process includes a first activation process and a second activation process performed sequentially; The first activation treatment includes: contacting a solution containing a first activating component with a filler coated with a silane layer; the second activation treatment includes: contacting a solution containing a second activating component with the product obtained from the first activation treatment; the first activating component contains amide groups, phenolic hydroxyl groups, and sulfone groups, and the second activating component contains carboxylic acid groups and sulfonic acid groups; In step (2), the mass ratio of the first activating component to the first initiator to the first solvent in the solution containing the first activating component is (13-26): (1-2): (220-280).

28. The method according to claim 27, wherein, The first solvent is selected from at least one of toluene, p-xylene, m-xylene, and o-xylene; And / or, the first activating component includes amide derivatives, phenolic derivatives, and sulfone derivatives.

29. The method according to claim 28, wherein, In the first activating component, the molar ratio of amide group: phenolic hydroxyl group: sulfone group is (0.2-10): (3-20):

1.

30. The method according to claim 27, wherein, In step (2), the first activation treatment conditions include: the liquid-to-solid volume ratio of the solution containing the first activation component to the filler coated with the silane layer in step (1) is 2-6, the immersion temperature is 52-73℃, and the time is 1-3h.

31. The method according to claim 27, wherein, In step (2), the mass ratio of the second activating component to the second initiator to the second solvent in the solution containing the second activating component is (13-28): (0.8-2.3): (230-280).

32. The method according to claim 31, wherein, The second solvent is selected from at least one of toluene, p-xylene, m-xylene, and o-xylene; And / or, the second activating component includes carboxylic acid derivatives and sulfonic acid derivatives.

33. The method according to claim 31, wherein, In the second activating component, the molar ratio of sulfonic acid group to carboxylic acid group is (0.75-3.5):

1.

34. The method according to claim 27, wherein, In step (2), the second activation treatment conditions include: the liquid-to-solid volume ratio of the solution containing the second activation component to the product obtained from the first activation treatment is 2-6, the soaking temperature is 53-72℃, and the time is 1-3h.

35. The method according to any one of claims 12-14, wherein, In step (2), after the activation treatment, the device needs to be soaked in a post-treatment agent for further treatment. The conditions for post-soaking treatment include: soaking time of 30-300 minutes.

36. The method according to claim 35, wherein, The post-treatment agent is selected from at least one of toluene, p-xylene, m-xylene, and o-xylene.

37. The method according to any one of claims 12-14, wherein, Step (2) further includes: pretreatment in a pretreatment agent, followed by drying under a protective atmosphere to obtain modified hydrolyzed filler.

38. The method according to claim 37, wherein, The pretreatment agent is anhydrous low-carbon alcohol.

39. The method according to claim 38, wherein, The pretreatment agent is anhydrous ethanol and / or anhydrous methanol.

40. The method of claim 37, wherein, The pretreatment conditions include: soaking time of 30-300 min, drying temperature of 110-130℃, and drying time of 10-30 min.

41. The application of the modified hydrolysis filler according to any one of claims 1-11 or the modified hydrolysis filler prepared by the preparation method according to any one of claims 12-40 in the hydrolysis of aldehyde fatty acid esters.

42. A method for preparing an aqueous solution of formaldehyde and formic acid, wherein, The method includes contacting the modified hydrolytic filler according to any one of claims 1-11 or the modified hydrolytic filler prepared by the preparation method according to any one of claims 12-40 with formaldehyde formate ester to carry out a hydrolysis reaction.