Modified resin as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of functional polymer materials, and particularly relates to modified resin as well as a preparation method and application thereof. The preparation method of the modified resin provided by the invention comprises the following steps: swelling a matrix resin, and carrying out a modification reaction with an aminopyrimidine compound to obtain the modified resin, wherein the matrix resin comprises macroporous resin, and the average pore size of the macroporous resin is 10 to 80 nm. The aminopyrimidine modified resin provided by the invention is used for removing organic matters in process tail gas, the total organic matter content in the tail gas is greatly reduced, the tail gas can be directly and safely discharged to the atmosphere, high-investment and high-energy-consumption treatment modes such as incineration are not needed, and the process is simple to operate, stable in operation and high in automation degree; the investment and operation cost can be greatly reduced, and the up-to-standard emission of tail gas is realized.

Description

Technical Field

[0001] The present application belongs to the technical field of functional polymer materials, and specifically relates to a modified resin and a preparation method and application thereof. Background Art

[0002] Isocyanate is an important organic reaction intermediate, widely used in household appliances, automobiles, construction, footwear, furniture, adhesives and other industries. Currently, most of the industrial production methods of isocyanate adopt the phosgenation method, which is prepared by mixing the corresponding primary amine with an inert solvent and then reacting it with phosgene through a phosgenation reaction and a series of post-treatment processes.

[0003] In the production of isocyanates by phosgenation, the main process involves phosgene synthesis, phosgenation reaction, isocyanate product refining, etc. At each process stage, process tail gas is discharged to the tail gas treatment system. In addition to conventional nitrogen, carbon monoxide, carbon dioxide and other gases, the process tail gas also includes a large amount of acidic gases, such as phosgene, hydrogen chloride, etc., and also carries a certain amount of reaction solvents and light organic components of reaction by-products. The conventional process for treating organic matter is to adsorb it with activated carbon and then discharge it into the atmosphere or send it for incineration. The use of activated carbon and other adsorption methods has the problem of low adsorption efficiency, and there is a risk of excessive organic matter in the tail gas. In addition, activated carbon is prone to pulverization during use, has a short operating life, and needs to be replaced frequently. The tail gas needs to add an online organic analyzer or frequent testing, resulting in high operating costs and a large amount of personnel operation. The incineration of tail gas requires a complete set of incineration systems, which requires a large investment and will cause waste of solvent resources.

[0004] The prior art also discloses a method for treating tail gas during the preparation of isocyanate, including a hydrogen chloride gas absorption process, a chlorine and organic component absorption process, an oxygen absorption process, and a phosgene decomposition process. This technology requires limiting the concentration of organic matter in the tail gas through front-end process control, but the concentration of organic matter in the tail gas is still higher than the environmental emission index, and the organic matter in the tail gas still needs to be further treated. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present application is to overcome the defects of the tail gas generated in the isocyanate preparation process in the prior art, such as excessive organic matter concentration after treatment and failure to meet environmental emission indicators, thereby providing a modified resin and its preparation method and application.

[0006] To this end, this application provides the following technical solutions:

[0007] According to one aspect of the present application, a method for preparing a modified resin is provided, comprising the following steps:

[0008] The base resin is swelled and subjected to modification reaction with an aminopyrimidine compound to obtain a modified resin;

[0009] Wherein, the matrix resin comprises a macroporous resin, and the average pore size of the macroporous resin is 10-80 nm.

[0010] As an example, the average pore size of the macroporous resin can be 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, or within a range consisting of any of the above values.

[0011] In some optional embodiments, the mass ratio of the base resin to the aminopyrimidine compound is 1:(1-5); as an example, the mass ratio of the base resin to the aminopyrimidine compound is 1:1, 1:2, 1:3, 1:4, 1:5, or within the range of any of the above values;

[0012] And / or, the aminopyrimidine compound includes at least one of 5-aminopyrimidine, 2-aminopyrimidine and triaminopyrimidine.

[0013] In some optional embodiments, the modification reaction temperature is 50-120°C; the modification reaction time is 1-10h; the stirring speed is 20-100r / min; as an example, the modification reaction temperature is 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, or within the range of any of the above values; the modification reaction time is 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, or within the range of any of the above values; the stirring speed is 20r / min, 30r / min, 40r / min, 50r / min, 60r / min, 70r / min, 80r / min, 90r / min, 100r / min, or within the range of any of the above values;

[0014] Optionally, the modification reaction temperature is 60-100° C.; the modification reaction time is 2-6 h; and the stirring speed is 30-60 r / min.

[0015] In some optional embodiments, the swelling operation includes: soaking the base resin in an organic solvent;

[0016] Optionally, the immersion time is 5-20h, optionally 10-15h, and the mass ratio of the base resin to the organic solvent is 1:(5-20); as an example, the immersion time is 5h, 7h, 9h, 10h, 12h, 14h, 15h, or within the range of any of the above values; the mass ratio of the base resin to the organic solvent is 1:5, 1:8, 1:10, 1:13, 1:15, 1:17, 1:20, or within the range of any of the above values.

[0017] In some optional embodiments, the preparation method of the base resin includes: mixing a monovinyl reactive monomer, a polyvinyl crosslinking agent, a porogen, an initiator, a dispersant, a surfactant, and water, and performing a polymerization reaction to obtain a base resin;

[0018] Optionally, the mass ratio of the monovinyl reaction monomer to the polyvinyl crosslinker is 1:(1-10); as an example, the mass ratio of the monovinyl reaction monomer to the polyvinyl crosslinker is 1:1, 1:2, 1:3, 1:5, 1:7, 1:9, 1:10, or within the range of any of the above values.

[0019] In the present application, the monovinyl reactive monomer includes at least one of an aromatic monovinyl monomer or an acrylate monovinyl monomer; typically, but not limited to, the aromatic monovinyl monomer includes but is not limited to at least one of vinyl pyridine compounds, styrene, methyl styrene, ethyl styrene, chlorostyrene, and bromostyrene; the acrylate monovinyl monomer includes but is not limited to at least one of acrylates and methacrylates, etc.; specifically, it may be methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, etc. The polyvinyl crosslinking agent includes at least one of divinylbenzene, dimethylpropylene glycol, polyvinyl acrylate compounds, and triphenylethylene.

[0020] Further optionally, the monovinyl reactive monomer includes a vinyl pyridine compound, and the vinyl pyridine compound includes at least one of vinyl pyridine and 2-methyl-5-vinyl pyridine;

[0021] And / or, the polyvinyl crosslinking agent includes a polyvinyl acrylate compound, and the polyvinyl acrylate compound includes at least one of dimethyl ethylene glycol acrylate, 1,6-hexanediol diacrylate, trimethylolpropane trimethacrylate, and allyl methacrylate.

[0022] In some optional embodiments, the polymerization reaction temperature is controlled to be 20-110°C; the polymerization reaction time is 1-10h; the stirring speed is 20-100r / min; as an example, the polymerization reaction temperature is controlled to be 20°C, 30°C, 50°C, 60°C, 70°C, 90°C, 100°C, 110°C, or within the range of any of the above values; the polymerization reaction time is 1h, 3h, 5h, 7h, 9h, 10h, or within the range of any of the above values; the stirring speed is 20r / min, 30r / min, 40r / min, 50r / min, 60r / min, 70r / min, 80r / min, 90r / min, 100r / min, or within the range of any of the above values;

[0023] Optionally, the polymerization reaction temperature is controlled at 40-80° C.; the polymerization reaction time is 2-6 h; and the stirring speed is 30-60 r / min.

[0024] In some optional embodiments, the mass ratio of the water phase to the oil phase is (1-20):1. As an example, the mass ratio of the water phase to the oil phase is 1:1, 3:1, 5:1, 8:1, 10:1, 12:1, 15:1, 17:1, 20:1, or within the range of any of the above values;

[0025] The aqueous phase includes a dispersant, a surfactant and water, and the oil phase includes a monovinyl reaction monomer, a polyvinyl crosslinking agent, a porogen and an initiator.

[0026] In some optional embodiments, based on the total mass of the aqueous phase, the mass proportion of the dispersant is 0.2%-2%, and the mass proportion of the surfactant is 0.2%-2%; as an example, the mass proportion of the dispersant in the aqueous phase is 0.2%, 0.5%, 0.8%, 1%, 1.3%, 1.5%, 1.7%, 2%, or within the range of any of the above values; the mass proportion of the surfactant is 0.2%, 0.5%, 0.8%, 1%, 1.3%, 1.5%, 1.7%, 2%, or within the range of any of the above values;

[0027] And / or, based on the total mass of the oil phase, the mass proportion of the porogen is 2%-20%, and the mass proportion of the initiator is 1%-5%; as an example, the mass proportion of the porogen in the oil phase is 2%, 5%, 8%, 10%, 13%, 15%, 17%, 20%, or within the range of any of the above values; the mass proportion of the initiator is 1%, 2%, 3%, 4%, 5%, or within the range of any of the above values.

[0028] According to another aspect of the present application, a modified resin prepared by the above preparation method is provided.

[0029] According to another aspect of the present application, there is provided a use of the above-mentioned modified resin in removing organic matter from process tail gas;

[0030] Optionally, the process tail gas is isocyanate production tail gas.

[0031] In some optional embodiments, the specific preparation method of the modified resin may include the following steps:

[0032] (a) Preparation of base resin: Add appropriate amounts of vinyl pyridine compound, acrylate compound, porogen, initiator, dispersant, surfactant and water into a reaction vessel, stir and carry out polymerization reaction, wash with anhydrous ethanol and deionized water to neutrality in sequence after the reaction, and vacuum dry to obtain base resin;

[0033] (b) Preparation of modified resin: The base resin is soaked in an organic solvent to swell, and an aminopyrimidine compound is added. The mixture is stirred and heated to react. After the reaction is completed, the resin is washed with anhydrous ethanol and deionized water in sequence until it is neutral, and then dried in vacuo to obtain an aminopyrimidine-modified resin.

[0034] In some optional embodiments, in step (a), the porogen may be any one or more of benzene, toluene, polyethylene glycol, white oil, liquid paraffin, C6-C25 alkane or alkanol.

[0035] In some optional embodiments, in step (a), the initiator can be one or more of benzoyl peroxide, sodium percarbonate, sodium persulfate, tert-butyl perbenzoate, diisopropylbenzene peroxide, isopropylbenzene hydroperoxide, and azobisisobutylonitrile.

[0036] In some optional embodiments, in step (a), the dispersant may be one or more of polyvinyl alcohol, gelatin, fatty acids, aliphatic amides, paraffins, celluloses, and the like.

[0037] In some optional embodiments, in step (a), the surfactant is one or more of sodium dodecyl sulfonate, sodium dodecyl sulfate, sodium secondary alkyl sulfonate, behenyl glyceride, and fatty acid diglyceride.

[0038] In some optional embodiments, after the reaction of step (a) is completed, a washing step is further included, specifically comprising: soaking the polymerized matrix resin in anhydrous ethanol for washing for 1-3 hours, and then soaking it in deionized water for washing for 1-3 hours.

[0039] In some optional embodiments, in step (a), after the resin is washed with water until it is neutral, it is placed in a vacuum drying oven in a nitrogen atmosphere at a drying temperature of 40-60° C. for a drying time of 2-10 h to obtain a matrix resin.

[0040] In some optional embodiments, in step (b), the organic solvent used in the swelling step may be one or more of methanol, ethanol, dichloromethane, dichloroethane, n-hexane, and hexadecane.

[0041] In some optional embodiments, in step (b), after the reaction is completed, a washing step is further included, and the specific operation can be: soaking the aminopyrimidine-modified resin in anhydrous ethanol for washing for 1-3 hours, and then soaking it in deionized water for washing for 1-3 hours.

[0042] In some optional embodiments, in step (b), the drying temperature is 50-80° C., and the drying time is 2-10 h to obtain a modified resin.

[0043] In the present application, the organic matter in the process tail gas includes one or more of chlorinated alkanes, chlorinated olefins, chlorinated aromatics, alkyl esters, carbonates, toluene and xylene.

[0044] The total organic matter content in the tail gas is 0.01%-10% by mass, preferably 0.05%-5%, more preferably 0.1%-2%, and the rest is nitrogen, carbon monoxide, carbon dioxide and other gases.

[0045] In the present application, the process for removing organic matter from process tail gas is a continuous adsorption process.

[0046] In some optional embodiments, the process method described in the present application is to send the process tail gas (isocyanate production tail gas) to a resin tower for adsorption, and the qualified tail gas is directly discharged into the atmosphere. After the resin is saturated with adsorption, it is regenerated by steam analysis, and the regenerated resin is circulated for adsorption.

[0047] In some optional implementations, the number of resin towers is 2-4, one of which is in a regeneration state, and the adsorption method is single-unit or 2-3 units in series adsorption.

[0048] In some optional embodiments, the resin tower adsorption temperature is 10-50°C, preferably 15-25°C.

[0049] In some optional embodiments, the resin tower air velocity is 100-1200h -1 , preferably 200-1000h -1 , more preferably 300-600h -1 .

[0050] In some optional embodiments, the resin tower adsorption cycle is 1-50h, preferably 2-30h, and more preferably 4-10h.

[0051] In some optional embodiments, the resin tower regeneration temperature is 100-140°C, preferably 110-130°C.

[0052] In some optional embodiments, the resin tower regeneration time is 0.5-4h, preferably 1-2h.

[0053] In some optional embodiments, after the organic matter in the process tail gas (isocyanate production tail gas) of the present application is treated with a modified resin, the total organic matter mass content in the tail gas can be reduced to below 20 ppm, preferably below 5 ppm.

[0054] The technical solution of this application has the following advantages:

[0055] The preparation method of the modified resin provided by the present application comprises the following steps: swelling the base resin, and performing a modification reaction with an aminopyrimidine compound to obtain a modified resin; wherein the base resin comprises a macroporous resin, and the average pore size of the macroporous resin is 10-80 nm. The resin modified by aminopyrimidine provided by the present application is used for the removal of organic matter in the process tail gas, and the total organic matter content in the tail gas is greatly reduced, and can be directly and safely discharged into the atmosphere without the need for high-investment and high-energy-consuming treatment methods such as incineration. The process is simple to operate, stable in operation, and highly automated, which can greatly reduce investment and operating costs and achieve standard tail gas emissions. Specifically, the present application modifies the macroporous resin with a specific pore size by aminopyrimidine, and adds some functional groups while ensuring a large molecular cross-linking degree, providing the resin with a large number of adsorption sites such as amine groups and N=C structures, having the advantages of large specific surface area and strong selective adsorption, and on the basis of being able to adsorb conventional non-polar organic gases, it also has good specific adsorption of chlorine-containing organic gases, and the adsorption removal rate of organic matter can reach more than 99.6%.

[0056] The preparation method of the modified resin provided in the present application can further improve the adsorption performance of the resin by preferably using vinyl pyridine compounds as the reaction monomers of the macroporous resin and acrylate compounds as the polyvinyl crosslinking agent, thereby increasing the adsorption removal rate of organic matter in the process exhaust gas to a maximum of 99.94%. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0058] Figure 1 is a process flow chart of the process tail gas treatment in the test example of this application;

[0059] Reference numerals:

[0060] 1. Process tail gas; 2. Primary resin adsorption tower; 3. Primary resin tower outlet gas; 4. Secondary resin adsorption tower; 5. Exhaust tail gas; 6. Steam; 7. Desorption resin tower; 8. Desorption waste liquid. DETAILED DESCRIPTION

[0061] The following examples are provided for a better understanding of the present application, but are not limited to the best implementation mode described, and do not limit the content and protection scope of the present application. Any product identical or similar to the present application obtained by anyone under the inspiration of the present application or by combining the features of the present application with other prior arts shall fall within the protection scope of the present application.

[0062] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0063] In the following examples and comparative examples, the main raw materials are from the following sources:

[0064] Vinylpyridine (99.5%, Sinopharm Reagent Co., Ltd.);

[0065] Dimethyl glycol acrylate (98.5%, Aladdin Reagent Co., Ltd.);

[0066] Toluene (analytical grade, Sinopharm Reagent Co., Ltd.);

[0067] Polyethylene glycol (average molecular weight 600, analytical grade, Sinopharm Reagent Co., Ltd.);

[0068] Azobisisobutyronitrile (99.0%, Sinopharm Reagent Co., Ltd.);

[0069] Gelatin (food grade, Zhejiang Yicun Biotechnology);

[0070] Sodium secondary alkyl sulfonate SAS60 (RSO3Na (R = C12 ~ C16), Shandong Yousuo Chemical);

[0071] 2-aminopyrimidine (99.5%, Sinopharm Reagent Co., Ltd.);

[0072] Anhydrous ethanol (99.8%, Sinopharm Reagent Co., Ltd.);

[0073] n-Hexane (99.8%, Sinopharm Reagent Co., Ltd.);

[0074] Liquid paraffin (Sinopharm Reagent Co., Ltd.);

[0075] Benzoyl peroxide (99%, Sinopharm Reagent Co., Ltd.);

[0076] Polyvinyl alcohol (average molecular weight 20,000, Aladdin Reagent Co., Ltd.);

[0077] Sodium dodecyl sulfate (98%, Sinopharm Reagent Co., Ltd.);

[0078] Methanol (99.9%, Aladdin Reagent Co., Ltd.);

[0079] Sodium percarbonate (99%, Aladdin Reagent Co., Ltd.);

[0080] Hydroxypropyl methylcellulose (98%, Sinopharm Reagent Co., Ltd.);

[0081] Behenyl glyceride (99%, Sinopharm Reagent Co., Ltd.);

[0082] Dioxane (97%, Sinopharm Reagent Co., Ltd.);

[0083] Styrene (99.5%, West Asia Reagent Co., Ltd.);

[0084] Divinylbenzene (99%, West Asia Reagent Co., Ltd.);

[0085] Tert-butylstyrene (99%, Aladdin Reagent Co., Ltd.);

[0086] Allyl methacrylate (98%, Sinopharm Reagent Co., Ltd.).

[0087] Example 1

[0088] This embodiment provides a modified resin, and its specific preparation method and operating parameters are as follows:

[0089] (a) Preparation of matrix resin: Add appropriate amount of vinyl pyridine, dimethyl glycol acrylate, porogen toluene, initiator azobisisobutyronitrile, dispersant gelatin, surfactant sodium secondary alkyl sulfonate, and water into the reaction container, stir and heat to react, wherein the heating reaction temperature is controlled at 60°C; the reaction time is 4h; the stirring speed is 45r / min; the mass ratio of water phase to oil phase is 10:1, the mass proportion of dispersant in the water phase is 1%, and the mass proportion of surfactant is 1%; the mass proportion of porogen in the oil phase is 10%, the mass proportion of initiator is 3%, and the mass ratio of vinyl pyridine to dimethyl glycol acrylate is 1:5. After the reaction is completed, the polymerized matrix resin is soaked in anhydrous ethanol for washing for 2h, and then soaked in deionized water for washing for 2h. After the resin is washed to neutrality, it is placed in a vacuum drying oven in a nitrogen atmosphere at a drying temperature of 50°C and a drying time of 6h to obtain a matrix resin with an average pore size of 25nm;

[0090] (b) Preparation of modified resin: soak the base resin in an organic solvent, n-hexane, to swell for 12 hours, the mass ratio of the base resin to the organic solvent is 1:12, add aminopyrimidine, the mass ratio of the base resin to aminopyrimidine is 1:3, stir and heat to react, the reaction temperature is controlled at 80°C; the reaction time is 4 hours; the stirring speed is 45r / min, after the reaction is completed, soak the aminopyrimidine-modified resin in anhydrous ethanol for washing, the washing time is 2 hours. Then soak it in deionized water for washing, the washing time is 2 hours. Wash with deionized water until neutral, vacuum dry, the drying temperature is 70°C, and the drying time is 6 hours, to obtain a modified resin.

[0091] Example 2

[0092] This embodiment provides a modified resin, and its specific preparation method and operating parameters are as follows:

[0093] (a) Preparation of matrix resin: Add appropriate amount of vinyl pyridine, dimethyl glycol acrylate, porogen toluene, initiator azobisisobutyronitrile, dispersant gelatin, surfactant sodium secondary alkyl sulfonate, and water into a reaction container, stir and heat to react, wherein the heating reaction temperature is controlled at 20°C; the reaction time is 10h; the stirring speed is 100r / min; the mass ratio of water phase to oil phase is 1:1, the mass proportion of dispersant in water phase is 2%, and the mass proportion of surfactant is 2%; the mass proportion of porogen in oil phase is 2%, and the mass proportion of initiator is 1%, and the mass ratio of vinyl pyridine to dimethyl glycol acrylate is 1:1. After the reaction is completed, the polymerized matrix resin is soaked in anhydrous ethanol for washing for 1h, and then soaked in deionized water for washing for 1h. After the resin is washed to neutrality, it is placed in a vacuum drying oven in a nitrogen atmosphere at a drying temperature of 40°C and a drying time of 2h to obtain a matrix resin with an average pore size of 32nm;

[0094] (b) Preparation of modified resin: soak the base resin in an organic solvent, n-hexane, to swell for 5 hours, the mass ratio of the base resin to the organic solvent is 1:5, add aminopyrimidine, the mass ratio of the base resin to aminopyrimidine is 1:1, stir and heat to react, the reaction temperature is controlled at 50°C; the reaction time is 10 hours; the stirring speed is 100r / min, after the reaction is completed, soak the aminopyrimidine-modified resin in anhydrous ethanol for washing, the washing time is 1 hour. Then soak it in deionized water for washing, the washing time is 1 hour. Wash with deionized water until neutral, vacuum dry, the drying temperature is 50°C, and the drying time is 2 hours, to obtain a modified resin.

[0095] Example 3

[0096] This embodiment provides a modified resin, and its specific preparation method and operating parameters are as follows:

[0097] (a) Preparation of matrix resin: Add appropriate amount of vinyl pyridine, dimethyl glycol acrylate, porogen toluene, initiator azobisisobutyronitrile, dispersant gelatin, surfactant sodium secondary alkyl sulfonate, and water into a reaction container, stir and heat to react, wherein the heating reaction temperature is controlled at 110°C; the reaction time is 1h; the stirring speed is 20r / min; the mass ratio of water phase to oil phase is 20:1, the mass proportion of dispersant in water phase is 0.2%, and the mass proportion of surfactant is 0.2%; the mass proportion of porogen in oil phase is 20%, the mass proportion of initiator is 5%, and the mass ratio of vinyl pyridine to dimethyl glycol acrylate is 1:10. After the reaction is completed, the polymerized matrix resin is soaked in anhydrous ethanol for washing for 3h, and then soaked in deionized water for washing for 3h. After the resin is washed to neutrality, it is placed in a vacuum drying oven in a nitrogen atmosphere at a drying temperature of 60°C and a drying time of 10h to obtain a matrix resin with an average pore size of 45nm;

[0098] (b) Preparation of modified resin: soak the base resin in an organic solvent, n-hexane, to swell for 20 hours, the mass ratio of the base resin to the organic solvent is 1:20, add aminopyrimidine, the mass ratio of the base resin to aminopyrimidine is 1:5, stir and heat to react, the reaction temperature is controlled at 120°C; the reaction time is 1 hour; the stirring speed is 20r / min, after the reaction is completed, soak the aminopyrimidine-modified resin in anhydrous ethanol for washing, the washing time is 3 hours. Then soak it in deionized water for washing, the washing time is 3 hours. Wash with deionized water until neutral, vacuum dry, the drying temperature is 80°C, and the drying time is 10 hours, to obtain a modified resin.

[0099] Example 4

[0100] This embodiment provides a modified resin, and its specific preparation method and operating parameters are as follows:

[0101] (a) Preparation of matrix resin: Add appropriate amount of vinyl pyridine, dimethyl glycol acrylate, porogen toluene, initiator azobisisobutyronitrile, dispersant gelatin, surfactant sodium secondary alkyl sulfonate, and water into the reaction container, stir and heat to react, wherein the heating reaction temperature is controlled at 40°C; the reaction time is 6h; the stirring speed is 60r / min; the mass ratio of water phase to oil phase is 5:1, the mass proportion of dispersant in the water phase is 1.5%, and the mass proportion of surfactant is 1.5%; the mass proportion of porogen in the oil phase is 5%, and the mass proportion of initiator is 2%, and the mass ratio of vinyl pyridine to dimethyl glycol acrylate is 1:3. After the reaction is completed, the polymerized matrix resin is soaked in anhydrous ethanol for washing for 1.5h, and then soaked in deionized water for washing for 1.5h. After the resin is washed to neutrality, it is placed in a vacuum drying oven in a nitrogen atmosphere at a drying temperature of 45°C and a drying time of 4h to obtain a matrix resin with an average pore size of 68nm;

[0102] (b) Preparation of modified resin: soak the base resin in an organic solvent, n-hexane, to swell for 10 hours, the mass ratio of the base resin to the organic solvent is 1:10, add aminopyrimidine, the mass ratio of the base resin to aminopyrimidine is 1:2, stir and heat to react, the reaction temperature is controlled at 60°C; the reaction time is 6 hours; the stirring speed is 60r / min, after the reaction is completed, soak the aminopyrimidine-modified resin in anhydrous ethanol for washing, the washing time is 1.5 hours. Then soak it in deionized water for washing, the washing time is 1.5 hours. Wash with deionized water until neutral, vacuum dry, the drying temperature is 60°C, and the drying time is 4 hours, to obtain a modified resin.

[0103] Example 5

[0104] This embodiment provides a modified resin, and its specific preparation method and operating parameters are as follows:

[0105] (a) Preparation of matrix resin: Add appropriate amount of vinyl pyridine, dimethyl glycol acrylate, porogen toluene, initiator azobisisobutyronitrile, dispersant gelatin, surfactant sodium secondary alkyl sulfonate, and water into a reaction vessel, stir and heat to react, wherein the heating reaction temperature is controlled at 80°C; the reaction time is 2h; the stirring speed is 30r / min; the mass ratio of water phase to oil phase is 15:1, the mass proportion of dispersant in water phase is 0.5%, and the mass proportion of surfactant is 0.5%; the mass proportion of porogen in oil phase is 15%, the mass proportion of initiator is 4%, and the mass ratio of vinyl pyridine to dimethyl glycol acrylate is 1:8. After the reaction is completed, the polymerized matrix resin is washed with anhydrous ethanol for 2.5h, and then immersed in deionized water for washing for 2.5h. After the resin is washed to neutrality, it is placed in a vacuum drying oven in a nitrogen atmosphere at a drying temperature of 55°C and a drying time of 8h to obtain a matrix resin with an average pore size of 40nm;

[0106] (b) Preparation of modified resin: soak the base resin in an organic solvent, n-hexane, to swell for 15 hours, the mass ratio of the base resin to the organic solvent is 1:15, add aminopyrimidine, the mass ratio of the base resin to aminopyrimidine is 1:4, stir and heat to react, the reaction temperature is controlled at 100°C; the reaction time is 2 hours; the stirring speed is 30r / min, after the reaction is completed, soak the aminopyrimidine-modified resin in anhydrous ethanol for washing, the washing time is 2.5 hours. Then soak it in deionized water for washing, the washing time is 2.5 hours. Wash with deionized water until neutral, vacuum dry, the drying temperature is 75°C, and the drying time is 8 hours, to obtain a modified resin.

[0107] Example 6

[0108] This embodiment provides a modified resin, which is different from Embodiment 1 in that the porogen is liquid paraffin, the initiator is benzoyl peroxide, the dispersant is polyvinyl alcohol, the surfactant is sodium dodecyl sulfate, and the organic solvent is methanol.

[0109] Example 7

[0110] This embodiment provides a modified resin, which is different from Embodiment 1 in that the porogen is polyethylene glycol, the initiator is sodium percarbonate, the dispersant is hydroxypropyl methylcellulose, the surfactant is docosyl glyceride, and the organic solvent is hexadecane.

[0111] Example 8

[0112] This embodiment provides a modified resin, which is different from the embodiment 1 in that the reactive monomer is styrene and the cross-linking agent is divinylbenzene.

[0113] Example 9

[0114] This embodiment provides a modified resin, which is different from the embodiment 1 in that the reactive monomer is tert-butyl styrene and the cross-linking agent is allyl methacrylate.

[0115] Comparative Example 1

[0116] This comparative example directly adopts the base resin of Example 1.

[0117] Comparative Example 2

[0118] This comparative example provides a modified resin, which is different from Example 9 only in that an equal mass of pyrimidine is used to replace aminopyrimidine.

[0119] Comparative Example 3

[0120] This comparative example provides a modified resin, which is different from Example 9 in that an equal amount of 4-aminopyridine is used to replace aminopyrimidine.

[0121] Test Case

[0122] The modified resin or base resin provided in each embodiment and comparative example is used for removing organic matter from tail gas of isocyanate production. The process flow is as follows: Figure 1 As shown, this test example uses a resin tower with two-stage series adsorption and one-stage desorption regeneration to treat organic matter in the tail gas, but the present application is not limited thereto. The specific steps and operating parameters are as follows:

[0123] (1) The isocyanate production process tail gas 1 with a temperature of 20°C and a total organic matter mass concentration of about 0.5% (see Table 1 for details) is sent to a primary resin adsorption tower 2, wherein the chlorobenzene concentration in the tail gas is 0.2% and the adsorption tower air velocity is 500 h -1 ;

[0124] (2) After the tail gas is adsorbed by the primary resin adsorption tower 2, the outlet gas 3 of the primary resin adsorption tower is sent to the secondary resin adsorption tower 4 for series adsorption, and the qualified tail gas at the outlet of the secondary resin adsorption tower is discharged into the atmosphere (i.e., the discharged tail gas 5);

[0125] (3) The desorption resin tower 7 is regenerated by 2 barg steam 6, and the desorption waste liquid 8 is sent to the subsequent wastewater treatment system. The regeneration temperature is 125°C, the regeneration time is 1.5 hours, and waiting is performed after the regeneration is completed;

[0126] (4) The adsorption cycle of the primary and secondary resin adsorption towers is 6 hours. After the adsorption cycle, the primary resin adsorption tower is switched to the desorption resin tower, the secondary adsorption tower is switched to the primary adsorption tower, and the desorption resin tower is switched to the secondary adsorption tower;

[0127] (5) The above steps are repeated cyclically to achieve a continuous two-stage series adsorption and one-stage desorption regeneration process, thereby obtaining qualified tail gas.

[0128] Measurement method of total organic matter in tail gas before and after treatment:

[0129] The total organic content in the tail gas is determined by gas chromatography. First, the organic components contained in the tail gas are diluted with dichloromethane and anhydrous ethanol solution to different concentrations of standard solution, and then analyzed by gas phase. The peak area and concentration are plotted on EXCEL to draw a standard curve. Then, the organic matter in the tail gas of isocyanate production is absorbed by anhydrous ethanol, and the gas chromatography is used to determine the sample peak area and calculate its concentration using the standard curve.

[0130] Detector: Agilent 7890A, chromatographic column HP-5 (30m×0.25um×320μm). Chromatographic conditions: column temperature: 50℃ for 0.5min, 5℃ / min to 80℃ for 1min; 10℃ / min to 280℃ for 10min, injection port temperature: 280℃, detector temperature: 295℃, septum purge gas flow rate: 3.0mL / min, carrier gas (nitrogen) flow rate: 3mL / min, air flow rate: 350mL / min, hydrogen flow rate: 35mL / min, tail gas (nitrogen) flow rate: 25mL / min, split injection, split ratio 1:10, injection volume 0.5μL.

[0131] The specific test results are shown in the table below:

[0132] Table 1

[0133]

[0134]

[0135] From the data in the above table, it can be seen that the macroporous resin modified with aminopyrimidine compounds provides a large number of amine groups and N=C structures while ensuring a large degree of molecular cross-linking, thereby improving the specific adsorption capacity of the resin for organic matter.

[0136] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention.

Claims

1. A method for preparing a modified resin, characterized in that: The steps include: The base resin is swelled and subjected to modification reaction with an aminopyrimidine compound to obtain a modified resin; Wherein, the matrix resin comprises a macroporous resin, and the average pore size of the macroporous resin is 10-80 nm.

2. The method for preparing the modified resin according to claim 1, characterized in that: The mass ratio of the base resin to the aminopyrimidine compound is 1:(1-5); And / or, the aminopyrimidine compound includes at least one of 5-aminopyrimidine, 2-aminopyrimidine and triaminopyrimidine.

3. The method for preparing the modified resin according to claim 1, characterized in that: The modification reaction temperature is 50-120°C; the modification reaction time is 1-10h; the stirring speed is 20-100r / min; Optionally, the modification reaction temperature is 60-100° C.; the modification reaction time is 2-6 h; and the stirring speed is 30-60 r / min.

4. The method for preparing the modified resin according to claim 1, characterized in that: The swelling operation includes: soaking the base resin in an organic solvent; Optionally, the immersion time is 5-20 hours, optionally 10-15 hours, and the mass ratio of the base resin to the organic solvent is 1:(5-20).

5. The method for preparing the modified resin according to any one of claims 1 to 4, characterized in that: The preparation method of the base resin comprises: mixing a monovinyl reaction monomer, a polyvinyl crosslinking agent, a porogen, an initiator, a dispersant, a surfactant and water, and performing a polymerization reaction to obtain the base resin; Optionally, the mass ratio of the monovinyl reactive monomer to the polyvinyl crosslinking agent is 1:(1-10); Further optionally, the monovinyl reactive monomer includes at least one of an aromatic monovinyl monomer or an acrylate monovinyl monomer; optionally, the monovinyl reactive monomer includes a vinyl pyridine compound, and the vinyl pyridine compound includes at least one of vinyl pyridine and 2-methyl-5-vinyl pyridine; And / or, the polyvinyl cross-linking agent includes at least one of divinylbenzene, ethylene dimethacrylate, polyvinyl acrylate compounds, and triphenylethylene; optionally, the polyvinyl cross-linking agent includes polyvinyl acrylate compounds, and the polyvinyl acrylate compounds include at least one of dimethylethylene glycol acrylate, 1,6-hexanediol diacrylate, and trimethylolpropane trimethacrylate.

6. The method for preparing the modified resin according to claim 5, characterized in that: The polymerization reaction temperature is 20-110°C; the polymerization reaction time is 1-10h; the stirring speed is 20-100r / min; Optionally, the polymerization reaction temperature is 40-80° C.; the polymerization reaction time is 2-6 h; and the stirring speed is 30-60 r / min.

7. The method for preparing the modified resin according to claim 5, characterized in that: The mass ratio of water phase to oil phase is (1-20):1, The aqueous phase comprises a dispersant, a surfactant and water, and the oil phase comprises a monovinyl reaction monomer, a polyvinyl crosslinking agent, a porogen and an initiator.

8. The method for preparing the modified resin according to claim 7, characterized in that: Based on the total mass of the aqueous phase, the mass proportion of the dispersant is 0.2%-2%, and the mass proportion of the surfactant is 0.2%-2%; And / or, based on the total mass of the oil phase, the mass proportion of the porogen is 2%-20%, and the mass proportion of the initiator is 1%-5%.

9. A modified resin prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the modified resin according to claim 9 in removing organic matter from process tail gas; Optionally, the process tail gas is isocyanate production tail gas.

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