Hydrolyzed fillers, methods of making and using the same

Abstract

The present application relates to the technical field of hydrolysis of hydroxy fatty acid ester, and discloses a hydrolysis filler, a preparation method and application thereof. The hydrolysis filler comprises a silane layer and an active layer which are successively coated on the outer surface of the filler; the active layer comprises amido, pyrrolyl, and sulfhydryl and / or thioether, phosphoric acid group and sulfonic acid group. When the hydrolysis filler is used for hydrolysis of hydroxy fatty acid ester to prepare hydroxy glycolate aqueous solution, the water-ester ratio in the hydrolysis process and the oligomer content in the target product can be effectively reduced.

Description

Technical Field

[0001] This invention relates to the technical field of hydrolysis of hydroxy fatty acid esters, specifically to a hydrolysis filler, its preparation method, and its application. Background Technology

[0002] Glycoacetic acid esters contain both hydroxyl and ester functional groups, exhibiting the chemical properties of both alcohols and esters, making them widely applicable. Glycoacetic acid esters, such as methyl glycolate and ethyl glycolate, are excellent solvents for components in cellulose, resins, and rubber, and are widely used in organic and pharmaceutical synthesis. Furthermore, glycolic acid esters can be hydrolyzed to produce glycolic acid.

[0003] With the development of coal chemical technology, the production of ethylene glycol from syngas and the co-production of glycolic acid esters have gradually become the main source of glycolic acid esters. The process is briefly as follows: coal gasification produces carbon monoxide and hydrogen, which are then coupled with nitric oxide under the action of a catalyst to produce oxalate esters. The oxalate esters are then selectively catalytically hydrogenated to produce glycolic acid esters.

[0004] Glycolic acid, also known as glycolic acid, is the simplest α-amino acid. It is an important organic synthesis intermediate used in chemical cleaning and cosmetics. Furthermore, due to the biodegradability of glycolic acid polymers, it has wide applications in medical polymers such as suture reinforcement materials, bioabsorbable sutures, fracture fixation materials, drug delivery systems, and tissue engineering.

[0005] Patent application CN113101915A discloses a catalyst for the hydrolysis of methyl glycolate to synthesize glycolic acid and its preparation method: It discloses a gallium-aluminum solid solution hydrolysis catalyst prepared in situ using the active components of a Group III metal oxide or complex oxide solid solution and other metal oxide supports. The dissertation "Study on Homogeneous Catalytic Hydrolysis Process of Methyl Glycolate" (2014-Tianjin University) discloses the research results of batch and continuous hydrolysis distillation based on homogeneous catalysis and autocatalysis using sulfuric acid. Homogeneous catalysis processes show good performance, but face the problem of difficult separation of subsequent catalysts; impregnation methods or solid solution hydrolysis catalysts are prone to loss of active components during long-term operation, leading to a decrease in performance.

[0006] The paper "Modification of Cation Exchange Resins and Their Application in the Hydrolysis of Methyl Glycol to Glycolic Acid" (Industrial Catalysis, 2017, 25(8)) introduces the research on the modification of styrene-based strong acid cation exchange resins with AlCl3 and SnCl. The paper "Hydrolysis of Methyl Glycol to Glycolic Acid Process" (Industrial Catalysis, 2018, 26(4)) introduces the research on the catalytic hydrolysis of methyl glycolate to glycolic acid in a fixed-bed reactor using this modified resin, and its application in a pilot-scale plant with an annual production capacity of 1000 t / year of syngas to glycolic acid. Compared with commercially available cation exchange resins, the activity of the modified resin is regulated to a certain extent, making it more suitable for the hydrolysis system of glycolic acid esters. However, the water-ester ratio is still relatively high when using this catalyst.

[0007] When glycolic acid is used in high-end applications such as electronic-grade cleaning agents or polymer monomers, its quality requirements are high. However, glycolic acid is prone to polymerization when heated, easily decomposes at its boiling point, and has extremely low volatility, which significantly limits separation methods. During the hydrolysis of glycolic acid esters, if the water-to-ester ratio is high, both fixed-bed hydrolysis and reactive distillation processes face the problem of aqueous solution concentration and dehydration in the later stages. The dehydration and concentration process can lead to polymerization of heat-sensitive glycolic acid and a deepening of solution color. For high-end applications, such as electronic-grade chemical cleaning and biodegradable material polymerization, impurities such as oligomers in glycolic acid products can adversely affect the microscopic cleaning effect of circuit boards or silicon wafers, the molecular weight of polyglycolic acid, and the physicochemical properties of polymers. Therefore, low-water-ratio hydrolysis technology for glycolic acid esters is one of the important ways to improve the quality of glycolic acid products. Summary of the Invention

[0008] The purpose of this invention is to overcome the problems of high water-to-ester ratio and high oligomer formation during the hydrolysis of glycolic acid esters in the prior art, and to provide a hydrolysis filler, its preparation method and application. This hydrolysis filler is used in the hydrolysis of glycolic acid esters to effectively reduce the water-to-ester ratio and the oligomer content in the product during the hydrolysis process.

[0009] To achieve the above objectives, a first aspect of the present invention provides a hydrolyzed filler, wherein the hydrolyzed filler comprises a silane layer and an active layer sequentially coated on the outer surface of the filler; the active layer comprises amide groups, pyrrole groups, and mercapto groups and / or thioether groups, phosphate groups, and sulfonic acid groups.

[0010] Preferably, the active layer includes at least one active unit, the active unit including active layer A and active layer B, active layer A including amide groups, pyrrole groups, and mercapto groups and / or thioethers, and active layer B including phosphate groups and sulfonic acid groups.

[0011] Preferably, the active layer A and the active layer B are sequentially coated on the surface of the silane layer.

[0012] Preferably, in the active layer, the content of amide groups is 4-18 mmol / m² based on the surface area of ​​the dry-based filler. 2 The content of pyrrole groups is 32-46 mmol / m³. 2 The content of thiol groups and / or thioethers is 3-28 mmol / m 2 The content of phosphate and sulfonic acid groups is 13-80 mmol / m 2 .

[0013] A second aspect of the present invention provides a method for preparing a hydrolyzed filler, wherein the method includes:

[0014] (1) The packing is subjected to silanization treatment to obtain a packing coated with a silane layer;

[0015] (2) The filler coated with silane layer is subjected to at least one activation treatment using an active component to obtain a hydrolyzed filler;

[0016] The active components include amide groups, pyrrole groups, mercapto groups and / or thioether groups, phosphate groups and sulfonic acid groups.

[0017] The third aspect of the present invention provides the application of the hydrolyzable filler described in the first aspect or the hydrolyzable filler prepared by the preparation method described in the second aspect in the hydrolysis of the HO-R-COOH system, wherein R is a straight-chain or branched alkyl group with 1-3 carbon atoms, preferably in the application of hydrolyzed glycolic acid esters to prepare aqueous solutions of glycolic acid.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] During pilot and scale-up experiments, the inventors of this invention discovered that glycolic acid is a highly thermosensitive component, prone to polymerization at high temperatures and concentrations. Therefore, during the hydrolysis of glycolic acid esters, a relatively high water-to-ester ratio is typically chosen, resulting in significantly higher water consumption relative to the stoichiometric theory or the water consumption required for product specifications. This leads to a lower concentration of the glycolic acid hydrolysate, necessitating the addition of a glycolic 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 thermosensitive glycolic acid in the high-temperature distillation and concentration environment, leading to a higher amount of glycolic acid oligomers and a decline in product quality. This invention addresses this issue by enhancing the microscopic water environment distribution, thereby reducing the macroscopic water-to-ester molar ratio.

[0020] In this invention, a silane layer and an active 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 active layer from peeling and cracking. The single-use cycle is more than two years (it can be repaired during a major overhaul of the equipment). 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 glycolic acid and reducing the metal ion content in the product, thus improving product quality. Furthermore, the active layer contains hydrophilic groups, repulsive groups, and active groups. The various groups are overlapped and distributed to form a sandwich-like structure of suitable thickness, which can ensure the effective combination of "water-rich", "catalysis", and "diffusion", avoiding excessive thickness, and enabling glycolic acid ester, glycolic acid, and water to have good diffusion effects.

[0021] This hydrolysis packing material is used in fixed-bed hydrolysis or reactive distillation hydrolysis of glycolic acid esters. It can effectively reduce the water-ester ratio during hydrolysis, reduce the load on subsequent concentration and dehydration, prevent the polymerization of heat-sensitive glycolic acid during heating and concentration, and reduce the oligomer content in the product. Detailed Implementation

[0022] 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, one or more new numerical ranges are obtained by combining the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​with each other, and these numerical ranges should be considered as specifically disclosed herein.

[0023] The first aspect of the present invention provides a hydrolyzable filler, wherein the hydrolyzable filler comprises a silane layer and an active layer sequentially coated on the outer surface of the filler; the active layer comprises amide groups, pyrrole groups, and mercapto groups and / or thioether groups, phosphate groups, and sulfonic acid groups.

[0024] The inventors of this invention discovered in their research that coating the outer surface of the filler with a silane layer and an active layer, with the silane layer serving as a medium layer, forms (-Si-O-metal) chemical bonds on the filler surface. These chemical bonds exhibit good stability and improve the filler's resistance to acid corrosion. Furthermore, coating the silane layer with an active layer containing hydrophilic groups, repulsive groups, and active groups yields a hydrolyzed filler. The surface of the hydrolyzed filler forms a "sandwich" structure, enabling an effective combination of "water-rich," "catalytic," and "diffusion" functions, promoting the hydrolysis of glycolic acid esters and improving product quality.

[0025] In this invention, it is understood that the silane layer and active layer mentioned in this invention refer to the silane layer and active layer covering the outer surface of the filler, excluding the situation inside the filler. During the preparation process, it is inevitable that silane and active components will exist inside the filler, and this invention does not make any special limitation on this.

[0026] In this invention, the amide groups, pyrrole groups, and mercapto groups and / or thioethers in the active layer are determined by infrared spectroscopy. Specifically, the test conditions are KBr pellet compression at 400 cm⁻¹. -1 -4000cm -1 Scan within the range; phosphate and sulfonic acid groups are determined by titration, specifically by direct titration with 0.1 mol / L sodium hydroxide solution.

[0027] In a preferred embodiment, the active layer includes at least one active unit, the active unit including active layer A and active layer B, active layer A including amide groups, pyrrole groups, and mercapto groups and / or thioethers, and active layer B including phosphate groups and sulfonic acid groups.

[0028] In this invention, it is understood that the active layer including at least one active unit means that each active unit in the active layer exists in the form of an alternating structure of active layer A and active layer B, or active layer A and active 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.

[0029] In this invention, it is understood that the amide group, as a hydrophilic group, forms a hydrophilic layer on the surface of the filler, giving the hydrolyzed filler a good water absorption and swelling effect in the aqueous solution of glycolic acid ester. After water absorption and swelling, it can form a three-dimensional structure rich in water molecules. This structure can increase the water content relative to the bulk liquid phase by tens or even hundreds of times. Even in the case of hydrolysis with a low water-to-ester ratio, this active microstructure can still maintain a rich water form, reducing the amount of water used. The pyrrole group, as well as the mercapto group and / or thioether, are groups that repel glycolic acid molecules, which significantly reduces the solubility of glycolic acid in this structure. The glycolic acid produced by hydrolysis can diffuse into the bulk liquid phase in a timely manner, promoting the hydrolysis equilibrium to the right, so that the glycolic acid ester is close to complete hydrolysis. The phosphate group and sulfonic acid group, as active groups, have a catalytic effect, promote the hydrolysis reaction, and improve the hydrolysis conversion rate. The synergistic effect between the various groups promotes the hydrolysis reaction of glycolic acid ester, improves the conversion rate of glycolic acid ester, and enhances product quality.

[0030] In a particularly preferred embodiment, active layer A and active layer B are sequentially coated on the surface of the silane layer. In this invention, by grafting different functional groups in a stepwise manner, an active layer is formed on the filler surface, further promoting the hydrolysis reaction of glycolic acid esters, improving the conversion rate of glycolic acid esters and product quality.

[0031] In this invention, structured packing is selected as the matrix material, which can reduce the pressure drop in the reactor, effectively control the pressure range and corresponding operating temperature at the other end of the reactive distillation column or reactor, and improve product quality. Preferably, the packing is grid structured packing and / or corrugated structured packing. For example, the corrugated structured packing is plate corrugated structured packing and / or 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. Those skilled in the art can select according to actual needs.

[0032] In this invention, preferably, the filler material is metal, such as 304, 304L, 316, or 316L.

[0033] In this invention, preferably, the filler is a structured metal corrugated wire mesh filler.

[0034] 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 750-2300 m². 2 / m 3 .

[0035] In this invention, preferably, the molar ratio of the (-Si-O-Si-) group to the (-Si-OM) group in the silane layer is 1.1-4.2; wherein M is a metal derived from the filler. In this invention, the testing methods (infrared spectroscopy) for the (-Si-O-Si-) and (-Si-OM) groups are consistent with those described above, and will not be repeated here.

[0036] In this invention, preferably, the thickness of the silane layer is 1.5-6 micrometers. The thickness of the silane layer is measured using an X-ray fluorescence thickness gauge.

[0037] In this invention, by selecting the above-mentioned molar ratio and thickness of the silane layer, both high strength and excessive thickness are achieved, thus avoiding excessive reduction in the surface area of ​​the filler.

[0038] In this invention, there is no particular limitation on the types of substances in the silane layer, as long as the required functional groups can be provided. Preferably, 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.

[0039] In a preferred embodiment, the active layer contains 4-18 mmol / m² of amide groups, based on the surface area of ​​the dry-based filler per square meter. 2 The content of pyrrole groups is 32-46 mmol / m³. 2The content of thiol groups and / or thioethers is 3-28 mmol / m 2 The content of phosphate and sulfonic acid groups is 13-80 mmol / m 2 .

[0040] In a preferred embodiment, the active layer contains 11-18 mmol / m² of amide groups, based on the surface area of ​​the dry-based filler per square meter. 2 The content of pyrrole groups is 36-46 mmol / m³. 2 The content of thiol groups and / or thioethers is 8-28 mmol / m 2 The content of phosphate and sulfonic acid groups is 18-80 mmol / m 2 .

[0041] In a preferred embodiment, the active layer contains 3-14 mmol / m² of thiol groups, based on the surface area of ​​the dry-based filler per square meter. 2 The sulfide content is 3-14 mmol / m³. 2 More preferably, in the active layer, the content of thiol groups is 8-14 mmol / m² per square meter of dry-based filler surface area. 2 The content of sulfonic acid groups is 8-14 mmol / m 2 .

[0042] In a preferred embodiment, the active layer contains 13-26 mmol / m² of phosphate groups, based on the surface area of ​​the dry-based filler per square meter. 2 The content of sulfonic acid groups is 28-53 mmol / m 2 More preferably, in the active layer, the content of phosphate groups is 18-26 mmol / m² per square meter of dry-based filler surface area. 2 The content of sulfonic acid groups is 40-53 mmol / m 2 .

[0043] In this invention, by controlling the content of each group in the active layer, it has the advantages of suitable hydrolysis catalytic activity and promoting the shift of hydrolysis equilibrium.

[0044] In a preferred embodiment, the thickness of the active layer is 20-40 micrometers. The advantage of this preferred embodiment is that it has a suitable bulk structure, facilitating the diffusion of the hydrolysate water and the hydrolysate glycolic acid.

[0045] In this invention, the thickness of the active layer is measured using an X-ray fluorescence thickness gauge.

[0046] A second aspect of the present invention provides a method for preparing a hydrolyzed filler, wherein the method includes:

[0047] (1) The packing is subjected to silanization treatment to obtain a packing coated with a silane layer;

[0048] (2) The filler coated with silane layer is subjected to at least one activation treatment using an active component to obtain a hydrolyzed filler;

[0049] The active component contains amide, pyrrole, mercapto and / or thioether, phosphate and sulfonic acid groups.

[0050] The method provided by this invention has a simple and easy-to-control preparation process. It involves silanizing the filler and performing at least one activation treatment, coating the outer surface of the filler with a silane layer and an active layer, and giving full play to the synergistic relationship between the filler, the silane layer and the active layer, so that the prepared hydrolytic filler has good hydrolytic characteristics.

[0051] In this invention, the type, material, and specific surface area of ​​the filler in step (1) have been described in the first aspect and will not be repeated here.

[0052] In a preferred embodiment, in step (1), the thickness of the silane layer is 1.5-6 micrometers.

[0053] In this invention, the filler is 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).

[0054] In this invention, the method of silanization is not particularly limited, as long as the filler and the solution containing the silane reagent come into contact, such as a dip-coating method conventionally defined in the art. Preferably, the silanization process includes: contacting the filler with the solution containing the silane reagent, and then drying and curing it.

[0055] 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.

[0056] In this invention, there are no particular limitations on the preparation method of the silane-containing reagent solution. Preferably, in step (1), the silane-containing reagent solution is obtained by mixing the silane reagent, water, and anhydrous low-carbon alcohol, and then performing pre-hydrolysis.

[0057] In this invention, the selection range for pre-hydrolysis conditions is relatively wide. Preferably, the pre-hydrolysis time is 10-25 hours.

[0058] In a preferred embodiment, the volume ratio of silane reagent: water: anhydrous low alcohol is (2.8-5.2):(4-7):(90-95).

[0059] In a preferred embodiment, the pH value of the silane-containing reagent solution is 7.5-8.5.

[0060] In a preferred embodiment, the anhydrous low-carbon alcohol is anhydrous methanol and / or anhydrous ethanol, preferably anhydrous ethanol.

[0061] In this invention, there is no particular limitation on the type of silane reagent. Preferably, 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.

[0062] 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 1.1-4.2, and M is a metal from the filler.

[0063] 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 active layer, the active layer comprising amide groups, pyrrole groups, mercapto groups and / or thioether groups, phosphate groups and sulfonic acid groups.

[0064] In this invention, the types and contents of each group in the active layer, as well as their preferred range and testing methods, have been described in the first aspect and will not be repeated here.

[0065] In this invention, the activation treatment typically needs to be repeated to meet the content requirements of each functional group. Preferably, the activation treatment is performed 1-5 times. The advantages of this preferred embodiment are that the active layer has suitable activity, a faster diffusion rate, and a longer service life.

[0066] 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.

[0067] In a preferred embodiment, the pyrrole group is provided by a pyrrole derivative, preferably by at least one of methyl 4-vinyl-1H-pyrrole-3-carboxylate, methyl 5-vinyl-1H-pyrrole-2-carboxylate, 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole, 5-allyl-4-methoxy-1,5-dihydro-2H-pyrrole-2-one, 1-allyl-2-cyclopentyl-1H-pyrrole, 1-(1-phenylvinyl)pyrrole, 3-isopropenyl-1-methyl-pyrrole, and 1-allyl-2-isopropenyl-1H-pyrrole.

[0068] In a preferred embodiment, the mercapto group and / or thioether are provided by their respective derivatives, preferably by bis(4-methacryloylthiophenyl) thioether and / or allyl 2-mercaptopropionate.

[0069] In a preferred embodiment, the phosphate group is provided by a phosphate derivative, preferably by at least one of [2-methyl-2-(4-methylpent-3-enyl)cyclopropyl]methylphosphonophosphate, [(E)-6-cyclopropylidene-3-methylhex-2-enyl]phosphonophosphate, 2-(phosphonooxy)propane-1,3-dimethyldimethacrylate, and (2-fluoro-3,7-dimethyloct-1,6-dien-3-yl)phosphonophosphate.

[0070] 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.

[0071] 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 active component with a filler coated with a silane layer. The second activation treatment includes contacting a solution containing a second active component with the product obtained from the first activation treatment. The first active component contains amide groups, pyrrole groups, mercapto groups, and / or thioethers, and the second active component contains phosphate groups and sulfonic acid groups. The advantage of this preferred embodiment is that it forms a mixed layer of hydrophilic groups and glycolic acid repellent groups at the bottom of the active layer, facilitating the timely diffusion of the hydrolysis product glycolic acid from the aqueous layer.

[0072] In this invention, preferably, step (2) involves performing at least one first activation treatment and at least one second activation treatment. That is, in this invention, the first activation treatment and the second activation treatment must be performed alternately until the thickness of the active layer meets the requirements.

[0073] In a preferred embodiment, in step (2), the mass ratio of the first active component to the first initiator to the first solvent in the solution containing the first active component is (10-20):(0.8-2):(220-280).

[0074] In this invention, the type of the first initiator is not particularly limited, and it 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.

[0075] 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.

[0076] In this invention, there is no particular limitation on the type of the first active component, as long as the required functional groups can be provided. Preferably, the first active component includes amide derivatives, pyrrole derivatives, and thiol and / or thioether derivatives.

[0077] In a preferred embodiment, the molar ratio of amide group:pyrrole group:thiol group and / or thioether in the first active component is (0.2-6):(2.5-11):1.

[0078] In this invention, the selection range of conditions for the first activation treatment is relatively wide. Preferably, in step (2), the conditions for the first activation treatment include: the liquid-to-solid volume ratio of the solution containing the first active component to the filler coated with the silane layer in step (1) is 2-6, the immersion temperature is 50-70℃, and the time is 1-3h.

[0079] In a preferred embodiment, in step (2), the mass ratio of the second active component to the second initiator to the second solvent in the solution containing the second active component is (15-30):(1-2.5):(230-280).

[0080] In this invention, the range of types of the second initiator is the same as that of the first initiator, and will not be repeated here.

[0081] In this invention, the range of types of the second solvent is the same as that of the first solvent, and will not be repeated here.

[0082] In this invention, there is no particular limitation on the type of the second active component, as long as the required functional groups can be provided. Preferably, the second active component includes sulfonic acid derivatives and phosphoric acid derivatives.

[0083] In a preferred embodiment, the molar ratio of sulfonic acid groups to phosphate groups in the second active component is (1-5):1. The advantage of this preferred embodiment is that it allows the formation of catalytic groups on the upper layer of the active layer. The glycolic acid ester in the liquid phase is activated by these catalytic groups and then enters the water-rich layer, promoting the hydrolysis reaction.

[0084] In this invention, the selection range of conditions for the second active treatment is relatively wide. Preferably, in step (2), the conditions for the second active treatment include: the liquid-to-solid volume ratio of the solution containing the second active component to the product obtained from the first active treatment is 2-6, the soaking temperature is 55-75℃, and the time is 1-3h.

[0085] In a preferred embodiment, in step (2), the activated layer needs to be immersed in a post-treatment agent for further treatment. The advantage of this preferred embodiment is that it removes free modified components from the activated layer, facilitating mass transfer.

[0086] In this invention, there is no particular limitation on the type of post-treatment agent, and its selection range is the same as that of the first solvent and the second solvent. Preferably, the post-treatment agent is selected from at least one of toluene, p-xylene, m-xylene, and o-xylene.

[0087] 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.

[0088] In a preferred embodiment, step (2) further includes: pretreatment in a pretreatment agent to obtain the hydrolyzed filler. The advantage of this preferred embodiment is that it removes free polar components from the active layer, thus improving product purity.

[0089] In this invention, there is no particular limitation on the type of pretreatment agent. Preferably, the pretreatment agent is anhydrous ethanol and / or anhydrous methanol.

[0090] In this invention, step (2) of the pretreatment further includes drying under a protective atmosphere to obtain hydrolyzed filler. In this invention, the type of protective atmosphere is not particularly limited; for example, it may be nitrogen and / or an inert atmosphere, preferably nitrogen.

[0091] In this invention, there are no particular limitations on the conditions for pretreatment. Preferably, the conditions for pretreatment include: soaking time of 30-300 min, drying temperature of 110-130℃, and drying time of 10-30 min.

[0092] The third aspect of the present invention provides the application of the hydrolyzable filler described in the first aspect or the hydrolyzable filler prepared by the preparation method described in the second aspect in the hydrolysis of the HO-R-COOH system, wherein R is a straight-chain or branched alkyl group with 1-3 carbon atoms, preferably in the application of hydrolyzed glycolic acid esters to prepare aqueous solutions of glycolic acid, for example, by contacting the aqueous solution of glycolic acid esters with the hydrolyzable filler to obtain an aqueous solution of glycolic acid.

[0093] In this invention, the source of the glycolic acid ester is not particularly limited. Preferably, the glycolic acid ester is derived from at least one of the following methods: selective hydrogenation of dimethyl oxalate, addition of formaldehyde and hydrogen cyanide, one-step reaction of glyoxal and methanol, methyl formate-formaldehyde coupling, formaldehyde carbonylation, low-purity glycolic acid esterification, and polyglycolic acid alcoholysis.

[0094] In this invention, preferably, the reaction is carried out in a fixed-bed reactor and / or a reactive distillation column, and more preferably, the fixed-bed reactor and the reactive distillation column are used in series. Specifically, the fixed-bed reactor is used in series before the reactive purification column.

[0095] In this invention, the reaction conditions for the fixed-bed reactor are selected over a wide range. Preferably, the reaction temperature in the fixed-bed reactor is 50-90℃, and the reaction volume hourly space velocity is 1-3 h⁻¹. -1 The water-ester molar ratio is 2.5-15.

[0096] In this invention, the reaction conditions for the reactive distillation column are selected over a wide range. Preferably, 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 2.5-15.

[0097] In this invention, the hydrolytic filler described herein exhibits excellent performance in the hydrolysis reaction of glycolic acid esters. Preferably, the hydrolysis conversion rate of the glycolic acid ester is ≥99%, and the oligomer content in the aqueous glycolic acid solution is not higher than 3%, more preferably not higher than 2%, and even more preferably not higher than 1%.

[0098] In this invention, the oligomer refers to the dimer or higher polymer components of glycolic acid, the content of which is determined by liquid chromatography.

[0099] The present invention will be described in detail below through embodiments.

[0100] In this invention, the specific surface area of ​​the packing refers to the surface area of ​​a unit volume of packing.

[0101] In this invention, the content of each group in the active layer of the hydrolyzed filler is determined by the test method described above.

[0102] 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.

[0103] The formula for calculating the hydrolysis conversion rate of glycolic acid esters is:

[0104] Hydrolysis conversion rate (%) = (1 - Amount of residual raw material after hydrolysis / Total amount of raw material) × 100%

[0105] Example 1

[0106] The glycolic acid ester described in this embodiment is derived from the selective hydrogenation of dimethyl oxalate, and the water-ester molar ratio in the hydrolysis feedstock is 7:1.

[0107] The method for preparing the 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.

[0108] The packing material described in step (1) is a corrugated wire mesh structured packing with a specific surface area of ​​1550 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, a pretreatment is performed. 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.

[0109] The filler after silanization in step (1) is sequentially subjected to the first activation treatment, the first post-activation treatment, the second activation treatment, and the second post-activation treatment in step (2) to obtain an active layer. The solution containing the first active component used in the first active layer includes the first active component (the first active component includes amide derivatives, pyrrole derivatives, and mercapto derivatives, wherein the amide derivatives are selected from N,N'-[ethylenedi(oxymethylene)]di(acrylamide), the pyrrole derivatives are selected from methyl 4-vinyl-1H-pyrrole-3-carboxylic acid ester, and the mercapto derivatives are selected from allyl 2-mercaptopropionate), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The first active component, benzoyl peroxide, and solvent, by mass parts, are: first active component: benzoyl peroxide: solvent = 15.3:1.4:250. The amide derivatives, pyrrole derivatives, and mercapto derivatives, by molar ratio, are: amide group: pyrrole group: mercapto group = 3.1:6.8:1. The first active treatment conditions are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the first active component to the filler coated with silane layer obtained in step (1) is 4, the soaking temperature is 60°C, and the soaking time is 2 hours.

[0110] The product after the first activation treatment is then 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.

[0111] The obtained wet-based filler (the product of the first post-activation treatment) is subjected to a second activation treatment to obtain a second activated product. The solution containing the second active component is the second active component (the second active component includes phosphoric acid derivatives and sulfonic acid derivatives, wherein the phosphoric acid derivatives are selected from 2-(phosphoryloxy)propane-1,3-dimethyldimethacrylate, 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 active component, benzoyl peroxide, and solvent, by mass parts, are: second active component: benzoyl peroxide: solvent = 22.5: 1.8: 256. Among them, the sulfonic acid derivatives and phosphoric acid derivatives, by molar ratio, are: sulfonic acid group: phosphoric 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 active component to the product obtained in step (2) is 4, the treatment temperature is 65℃, and the treatment time is 2 hours.

[0112] The product after the second activation treatment undergoes a second post-activation treatment to obtain the product after the second activation treatment. The activation post-treatment agent used in the second activation post-treatment is p-xylene. The second activation post-treatment is performed by immersion for 60 minutes.

[0113] The wet-based packing material (the product of the second activation post-treatment) was subjected to one first activation repeat treatment and one second activation repeat treatment sequentially to obtain a repeatedly treated activated product. The repeatedly treated activated product underwent pretreatment to obtain 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 hydrolyzed packing material, the amide group content in the active layer was 11.3 mmol / m³. 2 The phosphate group content is 19.4 mmol / m 2 The content of sulfonic acid groups is 40.7 mmol / m 2 The content of pyrrole groups was 38.8 mmol / m³. 2 The thiol content is 8.6 mmol / m 2 The thickness of the active layer (active layer A and active layer B) is 30.4 micrometers.

[0114] The application of the hydrolysis packing material prepared in this embodiment in the hydrolysis of glycolic acid esters includes: contacting an aqueous solution of glycolic acid esters with the hydrolysis packing material to obtain an aqueous solution of glycolic acid esters. The application employs a combination of a fixed-bed reactor and a reactive distillation column, with the fixed-bed reactor connected in series before the reactive distillation column. In the fixed-bed reactor, the reaction temperature is 70°C and the reaction volume hourly space velocity (VHSV) is 2 h⁻¹. -1 The reactive distillation column has a theoretical plate number of 6, a reflux ratio of 1.7, and an operating pressure (absolute pressure) of 30 kPa.

[0115] In this example, the hydrolysis conversion rate of glycolic acid ester was 99.5%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 0.9%.

[0116] Example 2

[0117] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0118] 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 3The material is 304 stainless steel. The silanization treatment adopts the conventional dip-coating method in the art. Before the silanization treatment, a pretreatment is performed. 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 sequentially 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.

[0119] The filler after silanization in step (1) is sequentially subjected to step (2) first activation treatment, first post-activation treatment, second activation treatment, and second post-activation treatment to obtain an active layer. The solution containing the first active component used in the first active layer includes the first active component (the first active component includes amide derivatives, pyrrole derivatives, and mercapto derivatives, wherein the amide derivatives are selected from N,N'-[ethylenedi(oxymethylene)]di(acrylamide), the pyrrole derivatives are selected from methyl 4-vinyl-1H-pyrrole-3-carboxylic acid ester, and the mercapto derivatives are selected from allyl 2-mercaptopropionate), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The first active component, benzoyl peroxide, and solvent, by mass parts, are: first active component: benzoyl peroxide: solvent = 18.7: 1.8: 230. Wherein, the amide derivatives, pyrrole derivatives, and mercapto derivatives, by molar ratio, are: amide group: pyrrole group: mercapto group = 5.4: 9.7: 1. The first active treatment conditions are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the first active component to the filler coated with silane layer obtained in step (1) is 6, the soaking temperature is 68°C, and the soaking time is 2.9 hours.

[0120] The product after the first activation treatment is then 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.

[0121] 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 active component is the second active component (the second active component includes phosphoric acid derivatives and sulfonic acid derivatives, wherein the phosphoric acid derivatives are selected from 2-(phosphoryloxy)propane-1,3-dimethyldimethacrylate, 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 active component, benzoyl peroxide, and solvent, by mass parts, are: second active component: benzoyl peroxide: solvent = 28.6: 2.4: 240. Among them, the sulfonic acid derivatives and phosphoric acid derivatives, by molar ratio, are: sulfonic acid group: phosphoric acid group = 4.5: 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 active component to the product obtained in step (2) is 6, the treatment temperature is 73°C, and the treatment time is 2.7 hours.

[0122] The product after the second activation treatment undergoes a second post-activation treatment to obtain the product after the second activation treatment. The activation agent used in the second post-activation treatment is p-xylene. The second post-activation treatment is performed by immersion for 100 minutes.

[0123] Wet-based packing material (the product of the second activation post-treatment) underwent one first activation repeat treatment and one second activation repeat treatment to obtain a repeatedly treated activated product. This repeatedly treated activated product underwent pretreatment to obtain 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 114°C for 13 minutes. In the resulting hydrolyzed packing material, the amide group content in the active layer was 16.4 mmol / m³. 2 The phosphate group content is 24.2 mmol / m 2 The content of sulfonic acid groups is 49.8 mmol / m 2 The content of pyrrole groups was 43.5 mmol / m³. 2 The thiol content was 13.2 mmol / m 2 The thickness of the active layer (active layer A and active layer B) is 38.6 micrometers.

[0124] 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 1.2 h⁻¹. -1The reactive distillation column has a theoretical plate number of 4, a reflux ratio of 0.8, and an operating pressure (absolute pressure) of 19 kPa.

[0125] In this example, the hydrolysis conversion rate of glycolic acid ester was 99.7%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 0.4%.

[0126] Example 3

[0127] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0128] 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 3 The material is 304 stainless steel. The silanization treatment adopts the conventional dip-coating method in the art. Before the silanization treatment, a pretreatment is performed. 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 sequentially 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.

[0129] The filler after silanization in step (1) is sequentially subjected to step (2) first activation treatment, first post-activation treatment, second activation treatment, and second post-activation treatment to obtain an active layer. The solution containing the first active component used in the first active layer includes the first active component (the first active component includes amide derivatives, pyrrole derivatives, and mercapto derivatives, wherein the amide derivatives are selected from N,N'-[ethylenedi(oxymethylene)]di(acrylamide), the pyrrole derivatives are selected from methyl 4-vinyl-1H-pyrrole-3-carboxylic acid ester, and the mercapto derivatives are selected from allyl 2-mercaptopropionate), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The first active component, benzoyl peroxide, and solvent, by mass parts, are: first active component: benzoyl peroxide: solvent = 12.5: 1.1: 270. Wherein, the amide derivatives, pyrrole derivatives, and mercapto derivatives, by molar ratio, are: amide group: pyrrole group: mercapto group = 1.5: 4.2: 1. The first active treatment conditions are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the first active component to the filler coated with silane layer obtained in step (1) is 3, the soaking temperature is 52°C, and the soaking time is 1.2 hours.

[0130] 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.

[0131] 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 active component is the second active component (the second active component includes phosphoric acid derivatives and sulfonic acid derivatives, wherein the phosphoric acid derivatives are selected from 2-(phosphoryloxy)propane-1,3-dimethyldimethacrylate, 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 active component, benzoyl peroxide, and solvent, by mass parts, are: second active component: benzoyl peroxide: solvent = 17.3: 1.2: 270. Among them, the sulfonic acid derivatives and phosphoric acid derivatives, by molar ratio, are: sulfonic acid group: phosphoric acid group = 2.3: 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 active component to the product obtained in step (2) is 2, the treatment temperature is 58°C, and the treatment time is 1.3 hours.

[0132] The product after the second activation treatment undergoes a second post-activation treatment to obtain the product after the second activation treatment. The activation post-treatment agent used in the second activation post-treatment is p-xylene. The second activation post-treatment is performed by immersion for 40 minutes.

[0133] Wet-based packing material (the product of the second post-treatment) underwent a first and second repeated treatment to obtain a repeatedly treated active product. This repeatedly treated active product was then subjected to a 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 126°C for 25 minutes. The resulting hydrolyzed packing material had an amide group content of 7.4 mmol / m³ in the active layer. 2 The phosphate group content is 16.5 mmol / m 2 The content of sulfonic acid groups is 32.4 mmol / m 2 The content of pyrrole groups was 34.9 mmol / m³. 2 The thiol content is 6.8 mmol / m 2 The thickness of the active layer (active layer A and active layer B) is 24.4 micrometers.

[0134] 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 2.5 h⁻¹. -1 The reactive distillation column has a theoretical plate number of 8, a reflux ratio of 2.6, and an operating pressure (absolute pressure) of 46 kPa.

[0135] In this example, the hydrolysis conversion rate of glycolic acid ester was 99.3%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 1.3%.

[0136] Example 4

[0137] The method is the same as in Example 2, except that the water-ester molar ratio in the hydrolyzed raw material is 5:1.

[0138] In this example, the hydrolysis conversion rate of glycolic acid ester was 99.67%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 0.42%.

[0139] Example 5

[0140] The method is the same as in Example 2, except that the water-ester molar ratio in the hydrolyzed raw material is 3:1.

[0141] In this example, the hydrolysis conversion rate of glycolic acid ester was 99.65%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 0.44%.

[0142] Example 6

[0143] The method is the same as in Example 2, except that the water-ester molar ratio in the hydrolyzed raw material is 10:1.

[0144] In this example, the hydrolysis conversion rate of glycolic acid ester was 99.81%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 0.37%.

[0145] Example 7

[0146] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0147] The method is the same as in Example 3, except that no post-immersion treatment is performed after the first and second activation treatments.

[0148] In the obtained hydrolyzed packing material, the content of amide groups in the active layer is 7.3 mmol / m. 2 The phosphate group content is 16.2 mmol / m 2 The content of sulfonic acid groups is 31.9 mmol / m 2 The content of pyrrole groups was 34.5 mmol / m³. 2 The thiol content is 6.5 mmol / m 2 The thickness of the active layer is 23.8 micrometers.

[0149] Following the reaction method of Example 3, the hydrolysis conversion rate of glycolic acid ester in this example is 99.1%, and the oligomer content in the aqueous solution of the obtained glycolic acid product is 1.5%.

[0150] Example 8

[0151] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0152] The method is the same as in Example 3, except that a thioether derivative is used instead of a mercapto derivative in the first active component. The thioether derivative is selected from bis(4-methacryloylthiophenyl) thioether. The other components are the same.

[0153] The first active component, benzoyl peroxide, and solvent, by mass parts, are: first active component: benzoyl peroxide: solvent = 14.3: 1.2: 270. Among them, the amide derivatives, pyrrole derivatives, and thioether derivatives, by molar ratio, are: amide group: pyrrole group: thioether = 1.7: 4.3: 1.

[0154] In the obtained hydrolyzed packing material, the content of amide groups in the active layer is 7.3 mmol / m. 2 The phosphate group content is 16.6 mmol / m 2 The content of sulfonic acid groups is 32.5 mmol / m 2 The content of pyrrole groups was 34.8 mmol / m³. 2 The sulfide content is 6.4 mmol / m³. 2 The thickness of the active layer is 24.2 micrometers.

[0155] Following the reaction method in Example 3, the hydrolysis conversion rate of glycolic acid ester in this example was 99.3%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 1.2%.

[0156] Example 9

[0157] The hydrolyzed raw materials used in this embodiment are the same as those in Embodiment 1.

[0158] The method is the same as in Example 3, except that the activation treatment in step (2) is performed using a one-pot method.

[0159] The filler after silanization in step (1) is sequentially subjected to the first and second activation treatments, and the first and second activation treatments are repeated in step (2) to obtain an active layer. The solutions containing the first and second active components used in the first and second active layers are prepared by mixing equal volumes of the first active component solution and the second active component solution. The first active component solution includes the first active component (the first active component includes amide derivatives, pyrrole derivatives and mercapto derivatives, wherein the amide derivatives are selected from N,N'-[ethylenedi(oxymethylene)]di(acrylamide), the pyrrole derivatives are selected from methyl 4-vinyl-1H-pyrrole-3-carboxylate, and the mercapto derivatives are selected from allyl 2-mercaptopropionate), benzoyl peroxide and a solvent; the solvent is selected from toluene. The first active component, benzoyl peroxide and solvent, by mass parts, are: first active component: benzoyl peroxide: solvent = 12.5: 1.1: 270. The amide derivatives, pyrrole derivatives, and mercapto derivatives, in a molar ratio of amide group:pyrrole group:mercapto group = 1.5:4.2:1. The second active component solution includes a second active component (the second active component includes a phosphate derivative and a sulfonic acid derivative, wherein the phosphate derivative is selected from 2-(phosphoryloxy)propane-1,3-dimethyldimethacrylate, and the sulfonic acid derivative is selected from 2-hydroxy-3-(methacryloyloxy)-1-propanesulfonic acid), benzoyl peroxide, and a solvent; the solvent is selected from toluene. The active component, benzoyl peroxide, and solvent, in parts by mass, have a second active component:benzoyl peroxide:solvent ratio of 17.3:1.2:270. The sulfonic acid derivatives and phosphate derivatives, in a molar ratio of sulfonic acid group:phosphate group = 2.3:1. The treatment conditions for the first and second active treatments are as follows: the volume ratio (liquid-solid volume ratio) of the solution containing the first and second active components to the filler coated with silane layer obtained in step (1) is 3, the soaking temperature is 56°C, and the soaking time is 1.2 hours.

[0160] The filler material after the first and second activation treatments was then subjected to first and second post-activation treatments to obtain first and second post-activation products. The first and second post-activation agents used in the post-activation treatments were p-xylene. The first and second post-activation treatments were performed by immersion, with an immersion time of 40 minutes.

[0161] Wet-based packing material (products of the first and second activation treatments) underwent repeated first and second activation treatments to obtain repeatedly treated activated products. These repeatedly treated activated products were then subjected to pretreatment to obtain hydrolyzed packing material. Anhydrous ethanol was used as the pretreatment agent. The pretreatment method was immersion for 40 minutes, followed by drying in nitrogen at 126°C for 25 minutes. In the resulting hydrolyzed packing material, the amide group content in the active layer was 7.2 mmol / m³. 2 The phosphate group content is 16.3 mmol / m 2 The content of sulfonic acid groups is 32.1 mmol / m 2 The content of pyrrole groups was 34.5 mmol / m³. 2 The thiol content is 6.2 mmol / m 2 The thickness of the active layer (active layer A and active layer B) is 21.5 micrometers.

[0162] Following the reaction method in Example 3, the hydrolysis conversion rate of glycolic acid ester in this example was 98.6%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 1.7%.

[0163] Comparative Example 1

[0164] The method is the same as in Example 3, except that commercially available H-type D001 acidic resin is used to replace the active hydrolysis filler.

[0165] In this comparative example, the hydrolysis conversion rate of glycolic acid ester was 98.2%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 4.6%.

[0166] Comparative Example 2

[0167] The method is the same as in Example 6, except that commercially available H-type D001 acidic resin is used to replace the active hydrolysis filler.

[0168] In this comparative example, the hydrolysis conversion rate of glycolic acid ester was 98.6%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 3.5%.

[0169] Comparative Example 3

[0170] The method is the same as in Example 3, except that commercially available H-type D001 acidic resin is used to replace the active hydrolysis filler, and the water-ester molar ratio in the hydrolysis raw material is 20:1.

[0171] In this comparative example, the hydrolysis conversion rate of glycolic acid ester was 99.1%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 2.3%.

[0172] Comparative Example 4

[0173] The method is the same as in Example 3, except that commercially available H-type D001 acidic resin is used to replace the active hydrolysis filler, and the water-ester molar ratio in the hydrolysis raw material is 30:1.

[0174] In this comparative example, the hydrolysis conversion rate of glycolic acid ester was 99.2%, and the oligomer content in the aqueous solution of the obtained glycolic acid product was 1.4%.

[0175] 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 combinations of 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 hydrolyzable packing material, characterized in that, The hydrolysis filler includes a silane layer and an active layer sequentially coated on the outer surface of the filler; The active layer includes at least one active unit, the active unit includes active layer A and active layer B, active layer A includes amide group, pyrrole group, and mercapto group and / or thioether, and active layer B includes phosphate group and sulfonic acid group; In the active layer, based on the surface area of ​​the dry-based filler per square meter, the content of amide groups is 4-18 mmol / m². 2 The content of pyrrole groups is 32-46 mmol / m³. 2 The content of thiol groups and / or thioethers is 3-28 mmol / m 2 The content of phosphate and sulfonic acid groups is 13-80 mmol / m 2 ; The active layer includes at least one active unit, meaning that each active unit in the active layer exists in the form of an alternating structure of active layer A and active layer B, or active layer A and active layer B.

2. The hydrolysis packing material according to claim 1, wherein, The active layer A and active layer B are sequentially coated on the surface of the silane layer.

3. The hydrolysis packing material according to claim 1 or 2, 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 750-2300 m². 2 / m 3 .

4. The hydrolysis packing material according to claim 3, wherein, The packing material is a structured packing material made of corrugated metal wire mesh.

5. The hydrolysis packing material according to claim 3, wherein, In the silane layer, the molar ratio of the -Si-O-Si- group to the -Si-OM group is 1.1-4.2; where M is a metal derived from the filler. And / or, the thickness of the silane layer is 1.5-6 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.

6. The hydrolysis packing material according to claim 1 or 2, wherein, In the active layer, based on the surface area of ​​the dry-based filler per square meter, the content of amide groups is 11-18 mmol / m². 2 The content of pyrrole groups is 36-46 mmol / m³. 2 The content of thiol groups and / or thioethers is 8-28 mmol / m 2 The content of phosphate and sulfonic acid groups is 18-80 mmol / m 2 ; And / or, the thickness of the active layer is 20-40 micrometers.

7. The hydrolysis packing material according to claim 1 or 2, wherein, In the active layer, based on the surface area of ​​the dry-based filler per square meter, the content of thiol groups is 3-14 mmol / m². 2 The sulfide content is 3-14 mmol / m³. 2 .

8. The hydrolysis packing material according to claim 7, wherein, In the active layer, based on the surface area of ​​the dry-based filler per square meter, the content of thiol groups is 8-14 mmol / m². 2 The sulfide content is 8-14 mmol / m³. 2 .

9. The hydrolysis packing material according to claim 1 or 2, wherein, In the active layer, based on the surface area of ​​the dry-based filler per square meter, the content of phosphate groups is 13-26 mmol / m². 2 The content of sulfonic acid groups is 28-53 mmol / m 2 .

10. The hydrolysis packing material according to claim 9, wherein, In the active layer, based on the surface area of ​​the dry-based filler per square meter, the content of phosphate groups is 18-26 mmol / m². 2 The content of sulfonic acid groups is 40-53 mmol / m 2 .

11. A method for preparing the hydrolyzed filler according to claim 1, wherein, The preparation 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 subjected to at least one activation treatment using an active component to obtain a hydrolyzed filler; The active components include amide groups, pyrrole groups, mercapto groups and / or thioether groups, phosphate 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 active layer, which includes amide groups, pyrrole groups, mercapto groups and / or thioether groups, phosphate groups and sulfonic acid groups.

12. The method according to claim 11, 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 750-2300 m². 2 / m 3 .

13. The method according to claim 12, wherein, In step (1), the filler is a structured metal corrugated wire mesh filler.

14. The method according to any one of claims 11-13, wherein, In step (1), the thickness of the silane layer is 1.5-6 micrometers.

15. The method according to any one of claims 11-13, wherein, In step (1), the silanization process includes: contacting the filler with a solution containing a silane reagent, and then drying and curing it.

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, In step (1), 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, In step (1), 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 used 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 1.1-4.2, where M is a metal from the filler.

20. The method according to any one of claims 11-13, wherein, In step (2), The number of times the activity treatment is performed is 1-5 times.

21. The method according to any one of claims 11-13, wherein, In step (2), the active layer contains 11-18 mmol / m² of amide groups, based on the surface area of ​​the dry filler per square meter. 2 The content of pyrrole groups is 36-46 mmol / m³. 2 The content of thiol groups and / or thioethers is 8-28 mmol / m 2 The content of phosphate and sulfonic acid groups is 18-80 mmol / m 2 .

22. The method according to any one of claims 11-13, wherein, In step (2), the active layer contains 3-14 mmol / m² of thiol groups, based on the surface area of ​​the dry-based filler per square meter. 2 The sulfide content is 3-14 mmol / m³. 2 .

23. The method according to claim 22, wherein, In step (2), the active layer contains 8-14 mmol / m² of thiol groups, based on the surface area of ​​the dry-based filler per square meter. 2 The sulfide content is 8-14 mmol / m³. 2 .

24. The method according to any one of claims 11-13, wherein, In step (2), the active layer contains 13-26 mmol / m² of phosphate groups, based on the surface area of ​​the dry filler per square meter. 2 The content of sulfonic acid groups is 28-53 mmol / m 2 .

25. The method according to claim 24, wherein, In step (2), the active layer contains 18-26 mmol / m² of phosphate groups, based on the surface area of ​​the dry filler per square meter. 2 The content of sulfonic acid groups is 40-53 mmol / m 2 .

26. The method according to any one of claims 11-13, wherein, The amide group is provided by amide derivatives; And / or, the pyrrole group is provided by a pyrrole derivative; And / or, the thiol and / or thioether are provided by thiol and / or thioether derivatives; And / or, the phosphate group is provided by a phosphate derivative; And / or, the sulfonic acid group is provided by a sulfonic acid derivative.

27. The method according to claim 26, wherein, The amide group is provided by at least one of N,N'-[ethylenedi(oxymethylene)]bis(acrylamide), N,N′-(1,2-dihydroxyethylene)diacrylamide and hexamethylenebisacrylamide.

28. The method according to claim 26, wherein, The pyrrole group is provided by at least one of methyl 4-vinyl-1H-pyrrole-3-carboxylate, methyl 5-vinyl-1H-pyrrole-2-carboxylate, 1-(3-buten-1-yl)-2-vinyl-1H-pyrrole, 5-allyl-4-methoxy-1,5-dihydro-2H-pyrrole-2-one, 1-allyl-2-cyclopentyl-1H-pyrrole, 1-(1-phenylvinyl)pyrrole, 3-isopropenyl-1-methyl-pyrrole, and 1-allyl-2-isopropenyl-1H-pyrrole.

29. The method according to claim 26, wherein, The mercapto group and / or thioether are provided by bis(4-methacryloylthiophenyl) thioether and / or allyl 2-mercaptopropionate.

30. The method according to claim 26, wherein, The phosphate group is provided by at least one of [2-methyl-2-(4-methylpent-3-enyl)cyclopropyl]methylphosphonophosphate, [(E)-6-cyclopropylidene-3-methylhex-2-enyl]phosphonophosphate, 2-(phosphonooxy)propane-1,3-dimethyldimethacrylate and (2-fluoro-3,7-dimethyloctyl-1,6-dien-3-yl)phosphonophosphate.

31. The method according to claim 26, wherein, 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-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.

32. The method according to any one of claims 11-13, wherein, In step (2), the activation treatment includes a first activation treatment and a second activation treatment performed sequentially; The first activation treatment includes contacting a solution containing a first active component with a filler coated with a silane layer; the second activation treatment includes contacting a solution containing a second active component with the product obtained from the first activation treatment; the first active component contains amide groups, pyrrole groups, and mercapto groups and / or thioethers, and the second active component contains phosphate groups and sulfonic acid groups.

33. The method according to claim 32, wherein, In step (2), the first active component includes amide derivatives, pyrrole derivatives, and thiol and / or thioether derivatives.

34. The method according to claim 32, wherein, In step (2), the first active treatment conditions include: the liquid-to-solid volume ratio of the solution containing the first active component to the filler coated with the silane layer described in step (1) is 2-6, the soaking temperature is 50-70℃, and the time is 1-3h.

35. The method according to claim 32, wherein, In step (2), the mass ratio of the first active component, the first initiator, and the first solvent in the solution containing the first active component is (10-20): (0.8-2): (220-280).

36. The method according to claim 35, wherein, In step (2), the first solvent is selected from at least one of toluene, p-xylene, m-xylene and o-xylene.

37. The method according to claim 32, wherein, In step (2), the molar ratio of amide group: pyrrole group: mercapto group and / or thioether in the first active component is (0.2-6): (2.5-11):

1.

38. The method according to claim 32, wherein, In step (2), the second active component includes sulfonic acid derivatives and phosphoric acid derivatives.

39. The method according to claim 32, wherein, In step (2), the second activation treatment conditions include: the liquid-to-solid volume ratio of the solution containing the second active component to the product obtained from the first activation treatment is 2-6, the soaking temperature is 55-75℃, and the time is 1-3h.

40. The method according to claim 32, wherein, In step (2), the mass ratio of the second active component, the second initiator, and the second solvent in the solution containing the second active component is (15-30): (1-2.5): (230-280).

41. The method according to claim 40, wherein, In step (2), the second solvent is selected from at least one of toluene, p-xylene, m-xylene and o-xylene.

42. The method according to claim 32, wherein, In step (2), the molar ratio of sulfonic acid group to phosphate group in the second active component is (1-5):

1.

43. The method according to any one of claims 11-13, wherein, In step (2), the activated material is then immersed in a post-treatment agent for further treatment.

44. The method according to claim 43, wherein, In step (2), the post-treatment agent is selected from at least one of toluene, p-xylene, m-xylene and o-xylene.

45. The method according to claim 43, wherein, In step (2), the conditions for post-soaking treatment include: soaking time of 30-300 min.

46. ​​The method according to any one of claims 11-13, wherein, Step (2) also includes: pretreatment in a pretreatment agent to obtain hydrolyzed filler.

47. The method according to claim 46, wherein, In step (2), the pretreatment agent is anhydrous ethanol and / or anhydrous methanol.

48. The method according to claim 46, wherein, In step (2), the conditions for the pretreatment include: soaking time of 30-300 min, drying temperature of 110-130℃, and drying time of 10-30 min.

49. The application of the hydrolyzable filler according to any one of claims 1-10 or the hydrolyzable filler prepared by the preparation method according to any one of claims 11-48 in the hydrolysis of the HO-R-COOH system, wherein, R is a straight-chain or branched alkyl group with 1-3 carbon atoms.

50. The application according to claim 49, wherein, The application of the hydrolytic filler in the preparation of aqueous glycolic acid solution by hydrolysis of glycolic acid esters.

51. The application according to claim 49 or 50, wherein, The application is carried out in fixed-bed reactors and / or reactive distillation columns.

52. The application according to claim 51, wherein, The reaction temperature in the fixed-bed reactor is 50-90℃, and the reaction volume hourly space velocity is 1-3 h⁻¹. -1 The water-ester molar ratio is 2.5-15.

53. The application according to claim 51, wherein, 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 2.5-15.

54. The application according to claim 50, wherein, The hydrolysis conversion rate of the glycolic acid ester is ≥99%, and the oligomer content in the aqueous solution of glycolic acid is ≤3%. The oligomer refers to the polymeric components of glycolic acid that are dimer or higher.

55. The application according to claim 54, wherein, The oligomer content in the aqueous solution of glycolic acid is ≤2%.

56. The application according to claim 55, wherein, The oligomer content in the aqueous solution of glycolic acid is ≤1%.