Preparation method and application of efficient desulfurizing agent

Abstract

The invention discloses a preparation method and application of an efficient desulfurizing agent, and belongs to the technical field of desulfurizing agent preparation. The preparation method of the efficient desulfurizing agent comprises the following steps: step 1, adding ferric salt and magnesium salt into a container containing distilled water, stirring and dissolving to obtain a mixed solution A, then adding a modified template agent and a pore-forming agent into the container containing distilled water, stirring and dissolving to obtain a mixed solution B; 2, uniformly mixing the mixed solution A and the mixed solution B, heating and stirring to obtain a colloidal solid C, freeze-drying the colloidal solid C, calcining and grinding to obtain a spongy composite oxide; and step 3, adding the spongy composite oxide into a tetrahydrofuran solution containing the modifier, sealing and stirring, putting into a reaction kettle, carrying out hydrothermal reaction, and after the reaction is finished, filtering, washing and drying to obtain the efficient desulfurizer. The high-efficiency desulfurizing agent prepared by the method has an excellent desulfurizing effect.

Description

Technical Field

[0001] The invention belongs to the technical field of desulfurizing agent preparation, and in particular relates to a preparation method and application of a high-efficiency desulfurizing agent. Background Art

[0002] With the acceleration of the global industrialization process, energy consumption has increased dramatically. Coal combustion is one of the main energy supply methods. The SO2 produced during its combustion has become one of the main sources of air pollution. SO2 not only causes the formation of acid rain and destroys the natural ecosystem, but also has a serious impact on human health, such as causing respiratory diseases. Therefore, the development of efficient, economical and environmentally friendly desulfurization technology, especially the preparation of efficient desulfurizers, has become a research hotspot in the current environmental protection field.

[0003] In the coal combustion process, desulfurization technology is mainly divided into three categories: pre-combustion desulfurization, combustion desulfurization and post-combustion desulfurization. Among them, post-combustion desulfurization, namely flue gas desulfurization, is the most widely used technology at present. Flue gas desulfurization technology can be divided into wet desulfurization, dry desulfurization and semi-dry desulfurization. Wet desulfurization is widely used because of its high desulfurization efficiency and mature technology, but there are problems such as large equipment investment, high operating cost and difficult wastewater treatment. Dry and semi-dry desulfurization have the advantages of simple equipment, small footprint and no wastewater discharge, but the desulfurization efficiency is relatively low. Therefore, the development of efficient, low-cost and easy-to-operate desulfurizers and their preparation technology is of great significance to improve the flue gas desulfurization efficiency and reduce the desulfurization cost.

[0004] Patent CN108620074A discloses a method for preparing a high-efficiency desulfurizer, which comprises the following raw materials in parts by weight: 10-15 parts of coconut shell, 12-15 parts of peanut shell, 30-45 parts of nickel nitrate solution, 5-10 parts of calcium acetate, 2-5 parts of calcium oxide, 5-8 parts of calcium fluoride, 2-4 parts of magnesium oxide, and 2-9 parts of aluminum hydroxide. The desulfurizer prepared by this method not only has a good desulfurization effect, but also can utilize agricultural wastes such as coconut shells and peanut shells. However, the desulfurization effect of the desulfurizer prepared by this method still has room for improvement. Summary of the invention

[0005] The purpose of the present invention is to provide a preparation method and application of a high-efficiency desulfurizer, so as to solve the technical problem that the desulfurization effect of the desulfurizer in the prior art is poor.

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

[0007] The present invention provides a method for preparing a high-efficiency desulfurizing agent, comprising the following steps:

[0008] Step 1: adding iron salt and magnesium salt to a container containing distilled water, stirring and dissolving to obtain a mixed solution A, and then adding a modified template and a pore-forming agent to a container containing distilled water, stirring and dissolving to obtain a mixed solution B;

[0009] Step 2: Evenly mix the mixed solution A and the mixed solution B, heat and stir to obtain a colloidal solid C, freeze-dry the colloidal solid C, and then calcine and grind it to obtain a sponge-like composite oxide;

[0010] Step 3: Add the sponge-like composite oxide to the tetrahydrofuran solution containing the modifier, seal and stir, place in a reactor, perform hydrothermal reaction, filter, wash and dry after the reaction is completed to obtain a high-efficiency desulfurizer.

[0011] Preferably, in step 1, the iron salt is one or more combinations of iron nitrate, iron acetate, iron chloride, and iron hydroxide, the magnesium salt is one or more combinations of magnesium nitrate, magnesium chloride, magnesium carbonate, magnesium oxide, and magnesium sulfate, the molar ratio of the iron salt to the magnesium salt is 1:(0.05-0.2), the stirring time is 30-60 min, the pore-forming agent is one or more combinations of polystyrene, citric acid, and nano-microspheres, the mass ratio of the modified template agent to the pore-forming agent is 1:(0.4-0.6), and the stirring time is 30-60 min. ; In the step 2, the heating and stirring temperature is 70-80°C, the time is 4-8h, the calcination temperature is 350-550°C, the time is 2-6h, and the grinding particle size is 400-600 mesh; in the step 3, the mass ratio of the sponge-like composite oxide, the modifier and tetrahydrofuran is 1: (5-20): (50-75), the sealed stirring time is 4-8h, the hydrothermal reaction temperature is 120-160°C, the time is 12-24h, and the washing is carried out with anhydrous ethanol and distilled water, and the drying temperature is 60-80°C.

[0012] Preferably, the method for preparing the modified template comprises the following steps:

[0013] Q1: Add 2,3-dichloropyridine, L-proline and potassium carbonate to a container, add dimethyl sulfoxide, heat to reflux, cool, dilute, adjust pH, add ethyl acetate for extraction, wash, separate, dry, and vacuum filter to obtain intermediate 1;

[0014] Q2: Add the intermediate product 1 to a container containing thionyl chloride, reflux reaction, vacuum distillation after the reaction is completed, dissolve 2-amino-5-chloro-3-methylbenzoic acid in acetonitrile, add it to the container, add pyridine at room temperature, stir, then slowly add methanesulfonyl chloride under ice bath conditions, react at room temperature, precipitate at low temperature after the reaction is completed, filter, wash, precipitate again, filter, and obtain the intermediate product 2;

[0015] Q3: Add the intermediate product 2 into a pressure tube containing tetrahydrofuran, add methylamine after dissolution, react, extract, separate, wash, dry, vacuum filter, evaporate, and purify to obtain a modified template.

[0016] In the above process, the synthetic reaction formula of the modified template is as follows:

[0017]

[0018] The results of mass spectrometry analysis of intermediate product 1 were: m / z: 226.05 (100.0%), 228.05 (32.0%), 227.05 (11.6%), 229.05 (3.5%), 228.06 (1.0%); the results of mass spectrometry analysis of intermediate product 2 were: m / z: 371.02 (100.0%), 373.02 (64.1%), 372.03 (19.7%), 374.02 (13.2%), 375.02 (10.6%), 373.03 (2 .2%), 376.02 (2.0%), 375.03 (1.2%), 372.02 (1.1%); the results of mass spectrometry analysis of the modified template were: m / z: 402.07 (100.0%), 404.06 (63.9%), 403.07 (20.8%), 405.07 (13.4%), 406.06 (10.4%), 404.07 (2.8%), 407.06 (2.3%), 406.07 (1.6%), 403.06 (1.5%);

[0019] The pyridine ring structure contained in the modified template has a special electronic effect and spatial configuration, and can form a stable interaction with the sulfur-containing compound. The existence of the interaction can accelerate the desulfurization reaction and improve the desulfurization efficiency. The interaction can also protect the structure of the desulfurizer, prevent it from being damaged, and enhance the stability of the desulfurizer. The existence of the modified template will cause the desulfurizer to form a specific pore structure that is more suitable for the adsorption and catalytic conversion of sulfur-containing compounds during the preparation process, thereby improving the desulfurization efficiency. At the same time, the desulfurizer will gradually lose its activity during the desulfurization process. The addition of the modified template can promote the regeneration reaction on the surface of the desulfurizer. When the desulfurizer loses its activity, the modified template can combine with the active site on the surface of the desulfurizer to form a new active center. The new active center can continue to react with the sulfur-containing compound to restore the desulfurization ability of the desulfurizer and improve its service life.

[0020] Preferably, in Q1, the molar ratio of 2,3-dichloropyridine, L-proline and potassium carbonate is (6.76-8.79):(8.11-10.54):(13.51-17.56), the heating reflux temperature is 100-120°C, the time is 20-24h, diluted with distilled water, adjusted to pH = 4-5, washed with saturated ammonium chloride, and dried with anhydrous sodium sulfate.

[0021] Preferably, in Q2, the molar ratio of the intermediate product 1, 2-amino-5-chloro-3-methylbenzoic acid, pyridine and methanesulfonyl chloride is (2.25-3.15): (2.04-2.86): (7.15-10.01): (2.45-3.43), the reflux reaction time is 8-10 hours, the stirring time is 30-45 minutes, the room temperature reaction time is 40-45 hours, the low-temperature precipitation temperature is 2-4°C, the precipitation time is 10-12 hours, and the product is washed with acetonitrile and distilled water; in Q3, the molar ratio of the intermediate product 2 and methylamine is (0.54-0.81): (1.61-2.42), the reaction time is 40-48 hours, the product is extracted with ethyl acetate and distilled water respectively, washed with saturated ammonium chloride, and dried with anhydrous sodium sulfate.

[0022] Preferably, the method for preparing the modifier comprises the following steps:

[0023] S1: Add triethylene glycol monomethyl ether to dichloromethane, stir to dissolve, add triethylamine, cool, then dropwise add acryloyl chloride, stir at room temperature, extract, rotary evaporate, and purify to obtain a colorless liquid;

[0024] S2: Styrene, 2-cyanopropane-2-ol dithiobenzoate, azobisisobutyronitrile and toluene are added to a container in sequence, nitrogen is introduced under low temperature, and then the container is placed in an oil bath to heat the reaction, and then the container is immersed in liquid nitrogen to terminate the reaction, and the polymer is slowly precipitated into methanol, filtered, precipitated, and vacuum dried to obtain a pink solid;

[0025] S3: Add colorless liquid, pink solid and azobisisobutyronitrile to tetrahydrofuran, stir to mix, degas, polymerize in an oil bath, then place in a liquid nitrogen environment to quench the reaction, expose to air, and then precipitate in cold methanol and vacuum dry to obtain a modifier.

[0026] In the above process, the synthetic reaction formula of the modifier is as follows:

[0027]

[0028] The hydrophilic chain segments contained in the modifier not only enhance the hydrophilicity of the polymer, but also improve the dispersibility and stability of the desulfurizer in the reaction system by forming interactions such as hydrogen bonds. The hydrophilic chain segments increase the hydrophilicity of the desulfurizer surface through hydrogen bonds, promote its contact with sulfur compounds, and improve the desulfurization efficiency. The steric hindrance effect produced by the modifier improves the desulfurization selectivity and reduces the adsorption of non-sulfur compounds.

[0029] Preferably, in S1, the amount ratio of triethylene glycol monomethyl ether, dichloromethane, triethylamine and acryloyl chloride is (5-10) g: (50-100) mL: (5.6-11.2) mL: (3.3-6.6) g, cooled to 0-1°C, stirred at room temperature for 10-12 h, extracted with dichloromethane and distilled water, and purified using ethyl acetate as eluent and silica gel as stationary phase.

[0030] Preferably, in S2, the dosage ratio of styrene, 2-cyanopropane-2-ol dithiobenzoate, azobisisobutyronitrile and toluene is (5-7.5) g: (0.049-0.07) g: (0.009-0.012) g: (4.6-6.9) mL, the low temperature environment temperature is 0-1°C, the nitrogen introduction time is 30-45 min, the heating reaction temperature is 80-85°C, the reaction time is 16-18 h, the vacuum drying temperature is 70-80°C, and the time is 20-24 h.

[0031] Preferably, in S3, the amount ratio of colorless liquid, pink solid, azobisisobutyronitrile and tetrahydrofuran is (0.26-0.52) g: (0.27-0.54) g: (0.0017-0.002) g: (1.3-2.6) mL, the oil bath polymerization temperature is 70-75°C, the polymerization time is 20-24h, the vacuum drying temperature is 30-40°C, and the time is 20-24h.

[0032] A method for applying a high-efficiency desulfurizer is disclosed, wherein the obtained high-efficiency desulfurizer is applied to coal desulfurization.

[0033] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0034] The sponge-like composite oxide itself has both catalytic and adsorption effects. The iron element can catalyze the conversion of SO2 into more active SO3, and the magnesium element can quickly react with acidic gases to achieve a desulfurization effect. In addition to its excellent composition, the microscopic morphology of the high-efficiency desulfurizer is a sponge-like structure with a loose structure and rich pores. It can not only provide more active sites, but also has excellent gas adsorption performance, which can give full play to the desulfurization effect. In addition, after the sponge-like composite oxide is modified, the surface groups are rich, which can not only further adsorb SO2, but also greatly improve the hydrophilicity, promote the interaction between SO2, H2O, and the high-efficiency desulfurizer, and improve the desulfurization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 It is an electron microscope image of the high-efficiency desulfurizer prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example 1: This example discloses a method for preparing a modified template, comprising the following steps:

[0039] Q1: 1.15 g 2,3-dichloropyridine, 1.07 g L-proline and 2.14 g potassium carbonate were added to a container, and 6 mL dimethyl sulfoxide was added, and the mixture was heated to reflux at 120°C for 24 h. After the reflux, the mixture was cooled, diluted with distilled water, and the pH was adjusted to 4. Ethyl acetate was added for extraction, and the mixture was washed with saturated ammonium chloride, separated, dried with anhydrous sodium sulfate, and vacuum filtered to obtain intermediate 1;

[0040] Q2: 1.2 g of intermediate product 1 was added to a container containing 3 mL of thionyl chloride, and the reaction was refluxed for 10 h. After the reaction was completed, vacuum distillation was performed. 0.82 g of 2-amino-5-chloro-3-methylbenzoic acid was dissolved in 30 mL of acetonitrile and added to the container. 1.21 g of pyridine was added at room temperature and stirred for 45 min. Then, 0.6 g of methylsulfonyl chloride was slowly added under ice bath conditions and the reaction was carried out at room temperature for 42 h. After the reaction was completed, low-temperature precipitation was performed at 4 ° C for 12 h, filtered, washed with acetonitrile and distilled water, precipitated again, and filtered to obtain intermediate product 2;

[0041] Q3: Add 1.31 g of intermediate product 2 into a pressure tube containing 3 mL of tetrahydrofuran, add 0.069 g of methylamine after dissolution, react for 48 hours, extract with ethyl acetate and distilled water respectively, separate the liquids, wash with saturated ammonium chloride, dry with anhydrous sodium sulfate, vacuum filter, evaporate, and purify to obtain a modified template.

[0042] This embodiment discloses a method for preparing a modifier, comprising the following steps:

[0043] S1: Add 7.5 g of triethylene glycol monomethyl ether to 75 mL of dichloromethane, stir to dissolve, add 8.4 mL of triethylamine, cool to 0°C, then drop 5.1 g of acryloyl chloride, stir at room temperature for 12 h, extract with dichloromethane and distilled water, purify with ethyl acetate as eluent and silica gel as stationary phase to obtain a colorless liquid;

[0044] S2: 6.25 g of styrene, 0.06 g of 2-cyanopropane-2-ol dithiobenzoate, 0.01 g of azobisisobutyronitrile and 5.7 mL of toluene were added to a container in sequence, nitrogen was introduced at 0°C for 45 min, and then the container was placed in an oil bath and heated at 85°C for 18 h. The container was then immersed in liquid nitrogen to terminate the reaction, and the polymer was slowly precipitated into methanol, filtered, precipitated, and vacuum dried at 80°C for 24 h to obtain a pink solid;

[0045] S3: Add 0.39 g of colorless liquid, 0.4 g of pink solid and 0.0018 g of azobisisobutyronitrile to 2 mL of tetrahydrofuran, stir to mix, degas, polymerize in an oil bath at 75°C for 24 h, then place in a liquid nitrogen environment to quench the reaction, expose to air, and then precipitate in cold methanol, and dry in vacuum at 40°C for 24 h to obtain a modifier.

[0046] This embodiment discloses a method for preparing a high-efficiency desulfurizer, comprising the following steps:

[0047] Step 1: Add 32.6 g of ferric nitrate and 2.5 g of magnesium nitrate to a container containing 100 mL of distilled water, stir for 60 min, and obtain a mixed solution A. Then, add 1 g of a modified template and 0.5 g of polystyrene to a container containing 10 mL of distilled water, stir for 60 min, and obtain a mixed solution B.

[0048] Step 2: Mix the mixed solution A and the mixed solution B evenly, heat and stir at 80° C. for 4 hours to obtain a colloidal solid C, freeze-dry the colloidal solid C, calcine at 550° C. for 4 hours, and grind to a particle size of 500 mesh to obtain a sponge-like composite oxide;

[0049] Step 3: Add 1g of sponge-like composite oxide to 62.5mL of tetrahydrofuran solution containing 12.5g of modifier, seal and stir for 8h, place in a reactor, and perform hydrothermal reaction at 160℃ for 24h. After the reaction, filter, wash with anhydrous ethanol and distilled water, and dry at 80℃ to obtain a high-efficiency desulfurizer.

[0050] Example 2: This example discloses a method for preparing a modified template, comprising the following steps:

[0051] Q1: 1 g 2,3-dichloropyridine, 0.93 g L-proline and 1.86 g potassium carbonate were added to a container, 6 mL dimethyl sulfoxide was added, and the mixture was heated to reflux at 120°C for 24 h. After the reflux, the mixture was cooled, diluted with distilled water, the pH was adjusted to 4, ethyl acetate was added for extraction, the mixture was washed with saturated ammonium chloride, the mixture was separated, the mixture was dried with anhydrous sodium sulfate, and vacuum filtered to obtain intermediate 1;

[0052] Q2: Add 1 g of intermediate product 1 to a container containing 3 mL of thionyl chloride, reflux for 10 h, and after the reaction is completed, vacuum distill. Dissolve 0.68 g of 2-amino-5-chloro-3-methylbenzoic acid in 30 mL of acetonitrile and add it to the container. Add 1.01 g of pyridine at room temperature and stir for 45 min. Then slowly add 0.5 g of methylsulfonyl chloride in an ice bath and react at room temperature for 42 h. After the reaction is completed, precipitate at 4 ° C for 12 h, filter, wash with acetonitrile and distilled water, precipitate again, and filter to obtain intermediate product 2;

[0053] Q3: Add 1.047 g of intermediate product 2 into a pressure tube containing 3 mL of tetrahydrofuran, add 0.055 g of methylamine after dissolution, react for 48 hours, extract with ethyl acetate and distilled water respectively, separate the liquids, wash with saturated ammonium chloride, dry with anhydrous sodium sulfate, vacuum filter, evaporate, and purify to obtain a modified template.

[0054] This embodiment discloses a method for preparing a modifier, comprising the following steps:

[0055] S1: Add 5 g of triethylene glycol monomethyl ether to 50 mL of dichloromethane, stir to dissolve, add 11.2 mL of triethylamine, cool to 0°C, then drop 3.3 g of acryloyl chloride, stir at room temperature for 12 h, extract with dichloromethane and distilled water, purify with ethyl acetate as eluent and silica gel as stationary phase to obtain a colorless liquid;

[0056] S2: 5 g styrene, 0.049 g 2-cyanopropane-2-ol dithiobenzoate, 0.012 g azobisisobutyronitrile and 4.6 mL toluene were added to a container in sequence, nitrogen was introduced at 0°C for 45 min, and then the container was placed in an oil bath and heated at 85°C for 18 h. The container was then immersed in liquid nitrogen to terminate the reaction, and the polymer was slowly precipitated into methanol, filtered, precipitated, and vacuum dried at 80°C for 24 h to obtain a pink solid;

[0057] S3: Add 0.26 g of colorless liquid, 0.27 g of pink solid and 0.0017 g of azobisisobutyronitrile to 1.3 mL of tetrahydrofuran, stir to mix, degas, polymerize in an oil bath at 75 °C for 24 h, then place in a liquid nitrogen environment to quench the reaction, expose to air, and then precipitate in cold methanol, and dry in vacuo at 40 °C for 24 h to obtain a modifier.

[0058] This embodiment discloses a method for preparing a high-efficiency desulfurizer, comprising the following steps:

[0059] Step 1: Add 32.6 g of ferric nitrate and 1 g of magnesium nitrate to a container containing 100 mL of distilled water, stir for 60 min, and obtain a mixed solution A. Then add 1 g of a modified template and 0.4 g of polystyrene to a container containing 10 mL of distilled water, stir for 60 min, and obtain a mixed solution B.

[0060] Step 2: Mix the mixed solution A and the mixed solution B evenly, heat and stir at 80° C. for 4 hours to obtain a colloidal solid C, freeze-dry the colloidal solid C, calcine at 550° C. for 4 hours, and grind to a particle size of 500 mesh to obtain a sponge-like composite oxide;

[0061] Step 3: Add 1g of sponge-like composite oxide to 50mL of tetrahydrofuran solution containing 5g of modifier, seal and stir for 8h, place in a reactor, and perform hydrothermal reaction at 160℃ for 24h. After the reaction, filter, wash with anhydrous ethanol and distilled water, and dry at 80℃ to obtain a high-efficiency desulfurizer.

[0062] Example 3: This example discloses a method for preparing a modified template, comprising the following steps:

[0063] Q1: 1.3 g 2,3-dichloropyridine, 1.21 g L-proline and 2.42 g potassium carbonate were added to a container, 6 mL dimethyl sulfoxide was added, and the mixture was heated to reflux at 120°C for 24 h. After the reflux, the mixture was cooled, diluted with distilled water, the pH was adjusted to 4, ethyl acetate was added for extraction, the mixture was washed with saturated ammonium chloride, the mixture was separated, the mixture was dried with anhydrous sodium sulfate, and vacuum filtered to obtain intermediate 1;

[0064] Q2: 1.4 g of intermediate product 1 was added to a container containing 3 mL of thionyl chloride, and the mixture was refluxed for 10 h. After the reaction, vacuum distillation was performed. 0.95 g of 2-amino-5-chloro-3-methylbenzoic acid was dissolved in 30 mL of acetonitrile and added to the container. 1.42 g of pyridine was added at room temperature and stirred for 45 min. Then, 0.71 g of methylsulfonyl chloride was slowly added under ice bath conditions and the mixture was reacted at room temperature for 42 h. After the reaction was completed, the mixture was precipitated at 4 °C for 12 h, filtered, washed with acetonitrile and distilled water, precipitated again, and filtered to obtain intermediate product 2.

[0065] Q3: Add 1.57 g of intermediate product 2 into a pressure tube containing 3 mL of tetrahydrofuran, add 0.083 g of methylamine after dissolution, react for 48 hours, extract with ethyl acetate and distilled water respectively, separate the liquids, wash with saturated ammonium chloride, dry with anhydrous sodium sulfate, vacuum filter, evaporate, and purify to obtain a modified template.

[0066] This embodiment discloses a method for preparing a modifier, comprising the following steps:

[0067] S1: Add 10 g of triethylene glycol monomethyl ether to 100 mL of dichloromethane, stir to dissolve, add 5.6 mL of triethylamine, cool to 0°C, then drop 6.6 g of acryloyl chloride, stir at room temperature for 12 h, extract with dichloromethane and distilled water, purify with ethyl acetate as eluent and silica gel as stationary phase to obtain a colorless liquid;

[0068] S2: 7.5 g styrene, 0.07 g 2-cyanopropane-2-ol dithiobenzoate, 0.009 g azobisisobutyronitrile and 6.9 mL toluene were added to a container in sequence, nitrogen was introduced at 0°C for 45 min, and then the container was placed in an oil bath and heated at 85°C for 18 h. The container was then immersed in liquid nitrogen to terminate the reaction, and the polymer was slowly precipitated into methanol, filtered, precipitated, and vacuum dried at 80°C for 24 h to obtain a pink solid;

[0069] S3: Add 0.52 g of colorless liquid, 0.54 g of pink solid and 0.002 g of azobisisobutyronitrile to 2.6 mL of tetrahydrofuran, stir to mix, degas, polymerize in an oil bath at 75°C for 24 h, then place in a liquid nitrogen environment to quench the reaction, expose to air, and then precipitate in cold methanol, and dry in vacuum at 40°C for 24 h to obtain a modifier.

[0070] This embodiment discloses a method for preparing a high-efficiency desulfurizer, comprising the following steps:

[0071] Step 1: Add 32.6 g of ferric nitrate and 4 g of magnesium nitrate to a container containing 100 mL of distilled water, stir for 60 min, and obtain a mixed solution A. Then, add 1 g of a modified template and 0.6 g of polystyrene to a container containing 10 mL of distilled water, stir for 60 min, and obtain a mixed solution B.

[0072] Step 2: Mix the mixed solution A and the mixed solution B evenly, heat and stir at 80° C. for 4 hours to obtain a colloidal solid C, freeze-dry the colloidal solid C, calcine at 550° C. for 4 hours, and grind to a particle size of 500 mesh to obtain a sponge-like composite oxide;

[0073] Step 3: Add 1g of sponge-like composite oxide to 75mL of tetrahydrofuran solution containing 20g of modifier, seal and stir for 8h, place in a reactor, and perform hydrothermal reaction at 160℃ for 24h. After the reaction, filter, wash with anhydrous ethanol and distilled water, and dry at 80℃ to obtain a high-efficiency desulfurizer.

[0074] Example 4: This example discloses a method for preparing a modified template, comprising the following steps:

[0075] Q1: 1.1 g 2,3-dichloropyridine, 0.98 g L-proline and 1.95 g potassium carbonate were added to a container, 6 mL dimethyl sulfoxide was added, and the mixture was heated to reflux at 120°C for 24 h. After the reflux, the mixture was cooled, diluted with distilled water, the pH was adjusted to 4, ethyl acetate was added for extraction, the mixture was washed with saturated ammonium chloride, the mixture was separated, the mixture was dried with anhydrous sodium sulfate, and vacuum filtered to obtain intermediate 1;

[0076] Q2: Add 1.1 g of intermediate product 1 to a container containing 3 mL of thionyl chloride, reflux for 10 h, and after the reaction, vacuum distill. Dissolve 0.71 g of 2-amino-5-chloro-3-methylbenzoic acid in 30 mL of acetonitrile and add to the container. Add 1.15 g of pyridine at room temperature and stir for 45 min. Then slowly add 0.55 g of methylsulfonyl chloride in an ice bath and react at room temperature for 42 h. After the reaction, precipitate at 4 ° C for 12 h, filter, wash with acetonitrile and distilled water, precipitate again, and filter to obtain intermediate product 2.

[0077] Q3: Add 1.25 g of intermediate product 2 into a pressure tube containing 3 mL of tetrahydrofuran, add 0.076 g of methylamine after dissolution, react for 48 hours, extract with ethyl acetate and distilled water respectively, separate the liquids, wash with saturated ammonium chloride, dry with anhydrous sodium sulfate, vacuum filter, evaporate, and purify to obtain a modified template.

[0078] This embodiment discloses a method for preparing a modifier, comprising the following steps:

[0079] S1: Add 6 g of triethylene glycol monomethyl ether to 80 mL of dichloromethane, stir to dissolve, add 6.8 mL of triethylamine, cool to 0°C, then drop 4.4 g of acryloyl chloride, stir at room temperature for 12 h, extract with dichloromethane and distilled water, purify with ethyl acetate as eluent and silica gel as stationary phase to obtain a colorless liquid;

[0080] S2: 5.5 g styrene, 0.052 g 2-cyanopropane-2-ol dithiobenzoate, 0.011 g azobisisobutyronitrile and 5.2 mL toluene were added to a container in sequence, nitrogen was introduced at 0°C for 45 min, and then the container was placed in an oil bath and heated at 85°C for 18 h. The container was then immersed in liquid nitrogen to terminate the reaction, and the polymer was slowly precipitated into methanol, filtered, precipitated, and vacuum dried at 80°C for 24 h to obtain a pink solid;

[0081] S3: Add 0.31 g of colorless liquid, 0.32 g of pink solid and 0.0019 g of azobisisobutyronitrile to 1.5 mL of tetrahydrofuran, stir to mix, degas, polymerize in an oil bath at 75 °C for 24 h, then place in a liquid nitrogen environment to quench the reaction, expose to air, and then precipitate in cold methanol, and dry in vacuum at 40 °C for 24 h to obtain a modifier.

[0082] This embodiment discloses a method for preparing a high-efficiency desulfurizer, comprising the following steps:

[0083] Step 1: Add 32.6 g of ferric nitrate and 2 g of magnesium nitrate to a container containing 100 mL of distilled water, stir for 60 min, and obtain a mixed solution A. Then, add 1 g of a modified template and 0.45 g of polystyrene to a container containing 10 mL of distilled water, stir for 60 min, and obtain a mixed solution B.

[0084] Step 2: Mix the mixed solution A and the mixed solution B evenly, heat and stir at 80° C. for 4 hours to obtain a colloidal solid C, freeze-dry the colloidal solid C, calcine at 550° C. for 4 hours, and grind to a particle size of 500 mesh to obtain a sponge-like composite oxide;

[0085] Step 3: Add 1g of sponge-like composite oxide to 55mL of tetrahydrofuran solution containing 10g of modifier, seal and stir for 8h, place in a reactor, and perform hydrothermal reaction at 160℃ for 24h. After the reaction, filter, wash with anhydrous ethanol and distilled water, and dry at 80℃ to obtain a high-efficiency desulfurizer.

[0086] Example 5: This example discloses a method for preparing a modified template, comprising the following steps:

[0087] Q1: 1.2 g 2,3-dichloropyridine, 1.17 g L-proline and 2.27 g potassium carbonate were added to a container, 6 mL dimethyl sulfoxide was added, and the mixture was heated to reflux at 120°C for 24 h. After the reflux, the mixture was cooled, diluted with distilled water, the pH was adjusted to 4, ethyl acetate was added for extraction, the mixture was washed with saturated ammonium chloride, the mixture was separated, the mixture was dried with anhydrous sodium sulfate, and vacuum filtered to obtain intermediate 1;

[0088] Q2: 1.3 g of intermediate product 1 was added to a container containing 3 mL of thionyl chloride, and the reaction was refluxed for 10 h. After the reaction was completed, vacuum distillation was performed, 0.91 g of 2-amino-5-chloro-3-methylbenzoic acid was dissolved in 30 mL of acetonitrile, and the mixture was added to the container. 1.37 g of pyridine was added at room temperature, and the mixture was stirred for 45 min. Then, 0.67 g of methylsulfonyl chloride was slowly added under ice bath conditions, and the reaction was carried out at room temperature for 42 h. After the reaction was completed, the mixture was precipitated at 4 ° C for 12 h, filtered, washed with acetonitrile and distilled water, precipitated again, and filtered to obtain intermediate product 2;

[0089] Q3: Add 1.48 g of intermediate product 2 into a pressure tube containing 3 mL of tetrahydrofuran, add 0.061 g of methylamine after dissolution, react for 48 hours, extract with ethyl acetate and distilled water respectively, separate the liquids, wash with saturated ammonium chloride, dry with anhydrous sodium sulfate, vacuum filter, evaporate, and purify to obtain a modified template.

[0090] This embodiment discloses a method for preparing a modifier, comprising the following steps:

[0091] S1: Add 8 g of triethylene glycol monomethyl ether to 60 mL of dichloromethane, stir to dissolve, add 10.3 mL of triethylamine, cool to 0°C, then drop 5.5 g of acryloyl chloride, stir at room temperature for 12 h, extract with dichloromethane and distilled water, purify with ethyl acetate as eluent and silica gel as stationary phase to obtain a colorless liquid;

[0092] S2: 7 g of styrene, 0.068 g of 2-cyanopropane-2-ol dithiobenzoate, 0.009 g of azobisisobutyronitrile and 6.1 mL of toluene were added to a container in sequence, nitrogen was introduced at 0°C for 45 min, and then the container was placed in an oil bath and heated at 85°C for 18 h. The container was then immersed in liquid nitrogen to terminate the reaction, and the polymer was slowly precipitated into methanol, filtered, precipitated, and vacuum dried at 80°C for 24 h to obtain a pink solid;

[0093] S3: Add 0.47 g of colorless liquid, 0.48 g of pink solid and 0.0018 g of azobisisobutyronitrile to 2.3 mL of tetrahydrofuran, stir to mix, degas, polymerize in an oil bath at 75°C for 24 h, then place in a liquid nitrogen environment to quench the reaction, expose to air, and then precipitate in cold methanol, and dry in vacuum at 40°C for 24 h to obtain a modifier.

[0094] This embodiment discloses a method for preparing a high-efficiency desulfurizer, comprising the following steps:

[0095] Step 1: Add 32.6 g of ferric nitrate and 3 g of magnesium nitrate to a container containing 100 mL of distilled water, stir for 60 min, and obtain a mixed solution A. Then, add 1 g of a modified template and 0.55 g of polystyrene to a container containing 10 mL of distilled water, stir for 60 min, and obtain a mixed solution B.

[0096] Step 2: Mix the mixed solution A and the mixed solution B evenly, heat and stir at 80° C. for 4 hours to obtain a colloidal solid C, freeze-dry the colloidal solid C, calcine at 550° C. for 4 hours, and grind to a particle size of 500 mesh to obtain a sponge-like composite oxide;

[0097] Step 3: Add 1g of sponge-like composite oxide to 65mL of tetrahydrofuran solution containing 15g of modifier, seal and stir for 8h, place in a reactor, and perform hydrothermal reaction at 160℃ for 24h. After the reaction, filter, wash with anhydrous ethanol and distilled water, and dry at 80℃ to obtain a high-efficiency desulfurizer.

[0098] Comparative Example 1: Compared with Example 1, in the preparation process of the modified template agent in Comparative Example 1, 2-amino-5-chloro-3-methylbenzoic acid is not added, and other conditions remain unchanged.

[0099] Comparative Example 2: Compared with Example 1, in the preparation process of the modifier in Comparative Example 2, triethylene glycol monomethyl ether was not added, and other conditions remained unchanged.

[0100] Comparative Example 3: Compared with Example 1, in the preparation process of the high-efficiency desulfurizer in Comparative Example 3, triethanolamine is used to replace the modified template agent, and other conditions remain unchanged.

[0101] Comparative Example 4: Compared with Example 1, in the preparation process of the high-efficiency desulfurizer in Comparative Example 4, no modifier is added, and other conditions remain unchanged.

[0102] Sampling was carried out according to GB / T 16157, the concentration of sulfur dioxide was tested according to HJ / T 56-2000, and the concentration change of sulfur dioxide before and after using the sample was measured. The sulfur dioxide reduction rate was calculated based on the sulfur dioxide reduction rate = [(C 前 -C 后 ) / C 前 ]×100%, the test results are shown in Table 1:

[0103] Table 1

[0104] project Sulfur dioxide reduction rate / % Example 1 97.87 Example 2 97.53 Example 3 97.21 Example 4 97.35 Example 5 97.11 Comparative Example 1 90.25 Comparative Example 2 90.29 Comparative Example 3 88.87 Comparative Example 4 88.30

[0105] It can be seen from the test results in Table 1 that the high-efficiency desulfurizer prepared in Examples 1-5 of the present invention has an excellent desulfurization effect. By comparing Comparative Example 1 with Examples 1-5, it can be seen that the addition of 2-amino-5-chloro-3-methylbenzoic acid can make the high-efficiency desulfurizer have an excellent desulfurization effect; by comparing Comparative Example 2 with Examples 1-5, it can be seen that the addition of triethylene glycol monomethyl ether can make the high-efficiency desulfurizer have an excellent desulfurization effect; by comparing Comparative Example 3 with Examples 1-5, it can be seen that the use of a modified template can improve the desulfurization effect of the high-efficiency desulfurizer; by comparing Comparative Example 4 with Examples 1-5, it can be seen that the use of a modifier can improve the desulfurization effect of the high-efficiency desulfurizer.

[0106] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0107] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing a high-efficiency desulfurizer, characterized in that: The following steps are involved: Step 1: adding iron salt and magnesium salt to a container containing distilled water, stirring and dissolving to obtain a mixed solution A, and then adding a modified template and a pore-forming agent to a container containing distilled water, stirring and dissolving to obtain a mixed solution B; Step 2: Evenly mix the mixed solution A and the mixed solution B, heat and stir to obtain a colloidal solid C, freeze-dry the colloidal solid C, and then calcine and grind it to obtain a sponge-like composite oxide; Step 3: Add the sponge-like composite oxide to the tetrahydrofuran solution containing the modifier, seal and stir, place in a reactor, perform hydrothermal reaction, filter, wash and dry after the reaction is completed to obtain a high-efficiency desulfurizer.

2. The method for preparing a high-efficiency desulfurizing agent according to claim 1, characterized in that: In the step 1, the iron salt is one or more combinations of iron nitrate, iron acetate, iron chloride, and iron hydroxide, the magnesium salt is one or more combinations of magnesium nitrate, magnesium chloride, magnesium carbonate, magnesium oxide, and magnesium sulfate, the molar ratio of the iron salt to the magnesium salt is 1:(0.05-0.2), the stirring time is 30-60 min, the pore-forming agent is one or more combinations of polystyrene, citric acid, and nano-microspheres, the mass ratio of the modified template agent to the pore-forming agent is 1:(0.4-0.6), and the stirring time is 30-60 min; In the step 2, the heating and stirring temperature is 70-80°C, the time is 4-8h, the calcination temperature is 350-550°C, the time is 2-6h, and the grinding particle size is 400-600 mesh; in the step 3, the mass ratio of the sponge-like composite oxide, the modifier and tetrahydrofuran is 1: (5-20): (50-75), the sealed stirring time is 4-8h, the hydrothermal reaction temperature is 120-160°C, the time is 12-24h, washing is carried out with anhydrous ethanol and distilled water, and the drying temperature is 60-80°C.

3. The method for preparing a high-efficiency desulfurizing agent according to claim 1, characterized in that: The preparation method of the modified template comprises the following steps: Q1: Add 2,3-dichloropyridine, L-proline and potassium carbonate to a container, add dimethyl sulfoxide, heat to reflux, cool, dilute, adjust pH, add ethyl acetate for extraction, wash, separate, dry, and vacuum filter to obtain intermediate 1; Q2: Add the intermediate product 1 to a container containing thionyl chloride, reflux reaction, vacuum distillation after the reaction is completed, dissolve 2-amino-5-chloro-3-methylbenzoic acid in acetonitrile, add it to the container, add pyridine at room temperature, stir, then slowly add methanesulfonyl chloride under ice bath conditions, react at room temperature, precipitate at low temperature after the reaction is completed, filter, wash, precipitate again, filter, and obtain the intermediate product 2; Q3: Add the intermediate product 2 into a pressure tube containing tetrahydrofuran, add methylamine after dissolution, react, extract, separate, wash, dry, vacuum filter, evaporate, and purify to obtain a modified template.

4. The method for preparing a high-efficiency desulfurizing agent according to claim 3, characterized in that: In the Q1, the molar ratio of 2,3-dichloropyridine, L-proline and potassium carbonate is (6.76-8.79): (8.11-10.54): (13.51-17.56), the heating reflux temperature is 100-120°C, the time is 20-24h, diluted with distilled water, adjusted to pH = 4-5, washed with saturated ammonium chloride, and dried with anhydrous sodium sulfate.

5. The method for preparing a high-efficiency desulfurizing agent according to claim 3, characterized in that: In the Q2, the molar ratio of the intermediate product 1, 2-amino-5-chloro-3-methylbenzoic acid, pyridine and methanesulfonyl chloride is (2.25-3.15): (2.04-2.86): (7.15-10.01): (2.45-3.43), the reflux reaction time is 8-10 hours, the stirring time is 30-45 minutes, the room temperature reaction time is 40-45 hours, the low-temperature precipitation temperature is 2-4°C, the precipitation time is 10-12 hours, and the product is washed with acetonitrile and distilled water; in the Q3, the molar ratio of the intermediate product 2 and methylamine is (0.54-0.81): (1.61-2.42), the reaction time is 40-48 hours, the product is extracted with ethyl acetate and distilled water respectively, washed with saturated ammonium chloride, and dried with anhydrous sodium sulfate.

6. The method for preparing a high-efficiency desulfurizing agent according to claim 1, characterized in that: The preparation method of the modifier comprises the following steps: S1: Add triethylene glycol monomethyl ether to dichloromethane, stir to dissolve, add triethylamine, cool, then dropwise add acryloyl chloride, stir at room temperature, extract, rotary evaporate, and purify to obtain a colorless liquid; S2: Styrene, 2-cyanopropane-2-ol dithiobenzoate, azobisisobutyronitrile and toluene are added to a container in sequence, nitrogen is introduced under low temperature, and then the container is placed in an oil bath to heat the reaction, and then the container is immersed in liquid nitrogen to terminate the reaction, and the polymer is slowly precipitated into methanol, filtered, precipitated, and vacuum dried to obtain a pink solid; S3: Add colorless liquid, pink solid and azobisisobutyronitrile to tetrahydrofuran, stir to mix, degas, polymerize in an oil bath, then place in a liquid nitrogen environment to quench the reaction, expose to air, and then precipitate in cold methanol and vacuum dry to obtain a modifier.

7. The method for preparing a high-efficiency desulfurizing agent according to claim 6, characterized in that: In the S1, the amount ratio of triethylene glycol monomethyl ether, dichloromethane, triethylamine and acryloyl chloride is (5-10) g: (50-100) mL: (5.6-11.2) mL: (3.3-6.6) g, cooled to 0-1°C, stirred at room temperature for 10-12 h, extracted with dichloromethane and distilled water, and purified with ethyl acetate as eluent and silica gel as stationary phase.

8. The method for preparing a high-efficiency desulfurizing agent according to claim 6, characterized in that: In the S2, the dosage ratio of styrene, 2-cyanopropane-2-ol dithiobenzoate, azobisisobutyronitrile and toluene is (5-7.5) g: (0.049-0.07) g: (0.009-0.012) g: (4.6-6.9) mL, the low temperature environment temperature is 0-1°C, the nitrogen introduction time is 30-45 min, the heating reaction temperature is 80-85°C, the reaction time is 16-18 h, the vacuum drying temperature is 70-80°C, and the time is 20-24 h.

9. The method for preparing a high-efficiency desulfurizing agent according to claim 6, characterized in that: In the S3, the amount ratio of the colorless liquid, the pink solid, azobisisobutyronitrile and tetrahydrofuran is (0.26-0.52) g: (0.27-0.54) g: (0.0017-0.002) g: (1.3-2.6) mL, the oil bath polymerization temperature is 70-75°C, the polymerization time is 20-24 h, and the vacuum drying temperature is 30-40°C, and the time is 20-24 h.

10. An application method of a high-efficiency desulfurizer, characterized in that: The obtained high-efficiency desulfurizer is applied to coal desulfurization.

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