Modified polyurethane sponge filler for farm odor treatment as well as preparation method and application of modified polyurethane sponge filler

Abstract

The invention relates to the technical field of farm waste gas treatment, and particularly provides a modified polyurethane sponge filler for farm odor treatment as well as a preparation method and application of the modified polyurethane sponge filler. The preparation method comprises the following steps: S1, soaking polyurethane sponge in a peroxide disinfectant for first dipping treatment; washing until the solution is neutral, taking out, and drying to obtain a polyurethane sponge matrix; s2, adding the charcoal powder into a ferric trichloride or nickel chloride solution, and uniformly stirring to obtain a modified solution; and immersing the polyurethane sponge matrix in the modified solution for secondary immersion treatment, and drying to obtain the modified polyurethane sponge filler. According to the preparation method, the adsorption performance of the polyurethane sponge filler can be improved, the adsorption capacity of malodorous gas is improved, the preparation method is simple and economical, common pig farm disinfectants such as peroxide disinfectants are adopted as modifiers, additional purchase and distribution are not needed, the transportation burden is relieved, and the operation cost of pig farms is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of waste gas treatment in breeding farms, and in particular to a modified polyurethane sponge filler for odor treatment in breeding farms, and a preparation method and application thereof. Background Art

[0002] In recent years, animal husbandry has accelerated its transformation and upgrading to standardized large-scale farming, and the scale rate of pig farming has become increasingly higher. The acceleration of the scale of pig farming has led to an increase in the emission of odorous gases, and the odorous gas pollution problem in large-scale pig farms has become increasingly obvious. Actively promoting the treatment of odorous gas pollution in pig farms is one of the important ways to help the green and circular development of the pig farming industry.

[0003] When designing and applying pig farm waste gas filtration systems, fillers are an important factor affecting the efficiency of odor treatment. Compared with ceramsite, volcanic rock and other fillers, polyurethane sponge fillers have the characteristics of large specific surface area, high porosity and strong stability, and are an ideal carrier material. However, there are problems such as low mass transfer rate and poor adsorption capacity, which in turn affects its large-scale production and application.

[0004] At present, the African swine fever epidemic situation is still severe. Domestic pig farms use fully closed management and strict disinfection measures to minimize the impact of the external environment and ensure that pigs can only grow healthily. The transportation inconvenience caused by closed management makes it more difficult to obtain and replace fillers. At the same time, the existing modification methods for polyurethane fillers are too complicated, for example: adding nanomaterials such as nano-SiO2 to polyurethane fillers to improve the surface properties of fillers; or using gelatin protein grafting methods for modification. These modification methods involve multiple steps and expensive materials, which will lead to a significant increase in pig farm operating costs. Against the background of rising pig farm operating costs, how to reasonably control the cost of filler modification and solve the transportation problems caused by closed pig farm management has become an important consideration. Summary of the invention

[0005] A brief overview of the disclosure is given below in order to provide a basic understanding of certain aspects of the disclosure. It should be understood that this overview is not an exhaustive overview of the disclosure. It is not intended to identify key or important parts of the disclosure, nor is it intended to limit the scope of the disclosure. Its purpose is simply to give certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0006] The purpose of the present invention is to provide a modified polyurethane sponge filler for odor control in pig farms and a preparation method and application thereof, so as to solve one of the problems existing in the prior art that the adsorption performance of the polyurethane sponge filler needs to be improved, the adsorption capacity for odorous gases needs to be improved, the transportation is difficult under the closed management conditions of the pig farm, and the operating cost of the pig farm is high.

[0007] In order to solve the above technical problems, the technical solution provided by the present disclosure is:

[0008] In a first aspect, a method for preparing a modified polyurethane filler for use in farm odor control comprises:

[0009] Step S1: soaking the polyurethane sponge in a peroxide disinfectant for a first immersion treatment; then washing the sponge until the solution is neutral, taking it out, and drying it to obtain a polyurethane sponge matrix;

[0010] Step S2: adding biochar powder to ferric chloride or nickel chloride solution, stirring evenly to obtain a modified solution; immersing the polyurethane sponge matrix in the modified solution for a second immersion treatment, and then drying to obtain a modified polyurethane sponge filler.

[0011] As a preferred embodiment of the preparation method of the modified polyurethane filler, in step S1, the peroxide disinfectant is a potassium persulfate solution; preferably, the mass concentration of the potassium persulfate solution is 0.5%-1.2%.

[0012] As a preferred embodiment of the preparation method of the modified polyurethane filler, in step S1, ultrasonic treatment is performed simultaneously with the first impregnation treatment, the ultrasonic treatment temperature is room temperature, the time is 15-30 minutes, and the ultrasonic power is 200-240W.

[0013] As a preferred embodiment of the preparation method of the modified polyurethane filler, in step S1, the washing treatment is to use 0.1 mol / L hydrochloric acid solution and 0.01 mol / L phosphate buffer solution for 2 to 3 times respectively.

[0014] As a preferred embodiment of the method for preparing the modified polyurethane filler, in step S1, the temperature of the drying treatment is 60-80°C.

[0015] As a preferred embodiment of the method for preparing the modified polyurethane filler, in step S2, the mass ratio of the biochar powder to the polyurethane sponge matrix is ​​1:5-10.

[0016] As a preferred embodiment of the method for preparing the modified polyurethane filler, in step S2, the particle size of the biochar powder is less than 75 μm, preferably 35-75 μm.

[0017] As a preferred embodiment of the preparation method of the modified polyurethane filler, in step S2, the biochar powder is first soaked in a 1 mol / L hydrochloric acid solution for 8 hours before use, then filtered, washed with deionized water, and dried.

[0018] As a preferred embodiment of the preparation method of the modified polyurethane filler, in step S2, the concentration of the ferric chloride solution or the nickel chloride solution is 0.05-0.2 mol / L, preferably 0.06-0.1 mol / L.

[0019] As a preferred embodiment of the preparation method of the modified polyurethane filler, in step S2, the second impregnation treatment is simultaneously performed with an oscillation treatment; the rotation speed of the oscillation treatment is 120-180 r / min, and the oscillation time is 1-3 h.

[0020] As a preferred embodiment of the method for preparing the modified polyurethane filler, in step S2, the temperature of the drying treatment is 60-80°C.

[0021] As a preferred embodiment of the preparation method of the modified polyurethane filler, in step S2, the addition of biochar powder is omitted, and ferric chloride or nickel chloride solution is directly used as the modification solution.

[0022] A modified polyurethane sponge filler is prepared by adopting the preparation method.

[0023] An application of the modified polyurethane sponge filler in the treatment of malodorous gases in a breeding farm, wherein the breeding farm is preferably a pig farm.

[0024] Compared with the prior art, the beneficial effects of the present invention include but are not limited to:

[0025] 1. The preparation method provided by the present invention improves the adsorption performance of the polyurethane sponge filler and increases the adsorption capacity of the filler for malodorous gases. The penetration adsorption capacity of ammonia gas by the polyurethane sponge filler prepared by the present invention can be as high as 407.62 g / cm 3 , or even higher, while the penetration adsorption capacity of ordinary polyurethane sponge for ammonia is 61.39g / cm 3 The adsorption capacity of the modified polyurethane filler is about 6 times that of the unmodified sponge.

[0026] 2. The present invention provides a method for chemically modifying a polyurethane sponge using a peroxide disinfectant commonly used in pig farms to increase the roughness of the outer surface and internal pore walls of the polyurethane sponge filler; and loading biochar powder and iron oxide on the surface of the sponge to further increase the specific surface area and porosity of the sponge, increase the number of oxygen-containing acidic groups such as hydroxyl groups on the surface of the filler, and increase its adsorption capacity for malodorous gases.

[0027] 3. The preparation method provided by the present invention is simple and economical, and adopts common pig farm disinfectant peroxide disinfectant as a modifier. There is no need to purchase and distribute it separately, which reduces the transportation burden and effectively reduces the operating cost of the pig farm. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The surface SEM images of the polyurethane filler before and after modification of Example 1 of the present invention (magnified 200 times), wherein (a) is the surface SEM image of the untreated polyurethane sponge, and (d) is the surface SEM image of the modified polyurethane sponge;

[0029] Figure 2 The surface SEM images of the polyurethane filler before and after modification of Example 1 of the present invention (magnified 2000 times), wherein (a) is the surface SEM image of the untreated polyurethane sponge, and (d) is the surface SEM image of the modified polyurethane sponge;

[0030] Figure 3 FTIR spectra of the polyurethane filler before and after modification in Example 1 of the present invention. DETAILED DESCRIPTION

[0031] The present invention provides a method for preparing a modified polyurethane filler for use in odor control in farms, and a specific implementation method thereof comprises the following steps:

[0032] Step S1: soaking the polyurethane sponge in a peroxide disinfectant for a first immersion treatment; then washing the sponge until the solution is neutral, taking it out, and drying it to obtain a polyurethane sponge matrix;

[0033] Step S2: adding biochar powder to ferric chloride or nickel chloride solution, stirring evenly to obtain a modified solution; immersing the polyurethane sponge matrix in the modified solution for a second immersion treatment, and then drying to obtain a modified polyurethane sponge filler.

[0034] In the above preparation method, the role of the peroxide disinfectant immersion is to oxidatively corrode the surface of the polyurethane sponge filler, thereby increasing the roughness of the outer surface and the inner pore wall of the polyurethane sponge filler.

[0035] The role of biochar is to further increase the specific surface area and adsorption sites of the filler through its developed pore structure and rich oxygen-containing functional groups, thereby enhancing the adsorption performance of NH3.

[0036] The role of loading metal oxides such as iron oxide is to increase the number of oxygen-containing acidic groups such as hydroxyl groups on the filler surface. During the gas phase adsorption process, the oxygen-containing acidic groups can react with NH3 to form hydrogen bonds, thereby firmly fixing the NH3 gas molecules and improving the NH3 adsorption capacity of the polyurethane sponge.

[0037] In the above preparation method, usually, the impregnation treatments in step S1 and step S2 are both complete impregnation treatments.

[0038] Preferably, in step S1, the peroxide disinfectant is a potassium persulfate solution. More preferably, the mass concentration of the potassium persulfate solution is 0.5%-1.2% (such as 0.6%, 0.8%, 1.0%, 1.1%, etc.).

[0039] Preferably, in step S1, the ultrasonic treatment is performed while the first immersion treatment is performed, the temperature of the ultrasonic treatment is room temperature, the time is 15-30 minutes (such as 18 minutes, 20 minutes, 22 minutes, 25 minutes, 28 minutes, etc.), and the ultrasonic power is 200-240W (such as 210W, 220W, 230W, etc.). Ultrasonic treatment can help shorten the reaction time and improve the treatment effect.

[0040] Preferably, in step S1, the washing treatment is washing 2 to 3 times using 0.1 mol / L hydrochloric acid solution and 0.01 mol / L phosphate buffer solution respectively.

[0041] Preferably, in step S1, the drying treatment temperature is 60-80°C (eg, 65°C, 70°C, 75°C, etc.).

[0042] Preferably, in step S2, the mass ratio of the biochar powder to the polyurethane sponge matrix is ​​1:5-10 (such as 1:6, 1:7, 1:8, 1:9, etc.).

[0043] Preferably, in step S2, the particle size of the biochar powder is less than 75 μm (such as 70 μm, 65 μm, 60 μm, 50 μm, 45 μm, 40 μm, etc.), preferably 35-75 μm.

[0044] Preferably, in step S2, the biochar powder is soaked in a 1 mol / L hydrochloric acid solution for 8 hours before use, filtered, washed with deionized water, and dried.

[0045] Preferably, in step S2, the concentration of the ferric chloride solution and the nickel chloride solution is 0.05-0.2 mol / L (such as 0.12 mol / L, 0.15 mol / L, 0.18 mol / L, etc.), more preferably 0.06-0.1 mol / L.

[0046] Preferably, in step S2, an oscillation treatment is performed simultaneously with the second impregnation treatment; the rotation speed of the oscillation treatment is 120-180 r / min (e.g., 130 r / min, 140 r / min, 150 r / min, 160 r / min, 170 r / min, etc.), and the oscillation time is 1-3 h (e.g., 1.5 h, 2 h, 2.5 h, etc.).

[0047] Preferably, in step S2, the drying treatment temperature is 60-80°C (eg, 65°C, 70°C, 75°C, etc.).

[0048] Optionally, in step S2, the addition of biochar powder is omitted, and ferric chloride or nickel chloride solution is directly used as the modification solution.

[0049] The invention also provides a modified polyurethane sponge filler, which is prepared by the above-mentioned preparation method.

[0050] Optionally, the modified polyurethane sponge filler includes: a polyurethane sponge matrix, and biochar powder adhered to its surface and / or interior, and iron oxide loaded on its surface and / or interior; the polyurethane sponge matrix is ​​a polyurethane sponge that has been soaked and corroded by an oxide disinfectant.

[0051] Optionally, the modified polyurethane sponge filler comprises: a polyurethane sponge matrix, and iron oxide loaded on the surface and / or inside thereof; the polyurethane sponge matrix is ​​a polyurethane sponge that has been soaked and corroded by an oxide-based disinfectant.

[0052] The present invention also provides the use of the modified polyurethane sponge filler in the treatment of malodorous gases in breeding farms, wherein the breeding farm is preferably a pig farm.

[0053] The following examples further illustrate the content of the present invention, but should not be construed as limiting the present invention. Without departing from the spirit and substance of the present invention, modifications or substitutions made to the methods, steps or conditions of the present invention belong to the scope of the present invention.

[0054] The technical solution of the present disclosure will be described below in conjunction with exemplary embodiments.

[0055] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0056] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0057] Example 1.1

[0058] Step S1: soaking the polyurethane sponge in a potassium persulfate solution with a mass concentration of 0.5wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0059] Step S2: At room temperature, add biochar powder (the mass ratio of biochar to polyurethane sponge matrix is ​​1:10) to 0.06 mol / L ferric chloride solution, stir evenly, and obtain a modified solution; immerse the polyurethane sponge matrix in the modified solution, and shake at 150 r / min for 2 hours. After completion, dry at 60° C. to obtain a modified polyurethane sponge filler.

[0060] The polyurethane filler before and after modification in this example was analyzed by SEM. Figure 1 and Figure 2 . After 200 times and 2000 times magnification, it can be observed that the untreated polyurethane sponge (a) has a cross-linked three-dimensional network structure, the sponge skeleton surface is smooth and has no obvious sediment or attachments, and there is a thin film layer at the filler pores, which will block the filler pores. From the surface SEM image of the modified polyurethane sponge (d), it can be observed that due to the strong oxidizing property of potassium persulfate, the pores blocked by the filler are cleaned, and the specific surface area and porosity of the filler are increased. At the same time, it can be observed that a large amount of biochar and iron oxides are attached to the pore walls of the polyurethane sponge, which significantly enhances the surface roughness of the filler and further increases the adsorption sites on the filler surface.

[0061] Figure 3 Showing 400-4000cm -1 The FTIR spectra of the polyurethane filler in this embodiment before and after modification are compared in the wavelength region. It is found that at 3290.4 cm -1 The absorption band at corresponds to the hydroxyl group (OH) in the polyurethane sponge. Figure 3 It can be observed that the strength of the OH group in the modified polyurethane sponge is significantly enhanced, indicating that the loading of iron oxide may attract more hydroxyl groups. Studies have shown that the more oxygen-containing acidic functional groups (hydroxyl groups, etc.) on the surface of the adsorbent material, the more protons H + The stronger the capacity of the site, the more ammonia can be adsorbed. Therefore, after the filler of the present invention is loaded and modified, the ammonia adsorption capacity is significantly increased.

[0062] The modified polyurethane sponge filler obtained in this example and the unmodified control polyurethane sponge filler are respectively loaded into the fixed bed adsorption column, and the adsorption column is connected according to the diagram. Then the gas cylinder pressure reducing valve and the gas flow meter are adjusted to stabilize the air pressure to 0.1MPa, and the gas flow rate is maintained at 200L / h. At the same time, the ammonia detector is turned on to detect the outlet ammonia concentration in real time. The time when the outlet concentration reaches the lowest point is the breakthrough time, and the time corresponding to the outlet concentration of 8ppm (80% of the initial concentration) is the adsorption end time. Finally, the adsorption performance of the modified composite material is evaluated by calculating the breakthrough adsorption capacity. The adsorption capacity of ammonia by the modified polyurethane sponge filler obtained in this example is 407.62g / cm 3The adsorption capacity of ammonia by the unmodified control polyurethane sponge filler (control example) is 61.39 g / cm 3 .

[0063] Example 1.2

[0064] Step S1: soaking the polyurethane sponge in a potassium persulfate solution with a mass concentration of 0.5wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0065] Step S2: At room temperature, add biochar powder (the mass ratio of biochar to polyurethane sponge matrix is ​​1:5) to 0.06 mol / L ferric chloride solution, stir evenly, and obtain a modified solution; immerse the polyurethane sponge matrix in the modified solution, and shake at 150 r / min for 2 hours. After completion, dry at 60° C. to obtain a modified polyurethane sponge filler.

[0066] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 355.95 g / cm 3 .

[0067] Example 1.3

[0068] Step S1: soaking the polyurethane sponge in a potassium persulfate solution with a mass concentration of 1.2wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0069] Step S2: At room temperature, add biochar powder (the mass ratio of biochar to polyurethane sponge matrix is ​​1:10) to 0.06 mol / L nickel chloride solution and stir evenly to obtain a modified solution. Immerse the polyurethane sponge matrix in the modified solution and shake at 150 r / min for 2 hours. After completion, dry at 60°C to obtain a modified polyurethane sponge filler.

[0070] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 306.91 g / cm 3 .

[0071] Example 1.4

[0072] Step S1: soaking the polyurethane sponge in a potassium persulfate solution with a mass concentration of 1.2wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0073] Step S2: At room temperature, add biochar powder (the mass ratio of biochar to polyurethane sponge matrix is ​​1:10) to 0.06 mol / L ferric chloride solution, stir evenly, and obtain a modified solution; immerse the polyurethane sponge matrix in the modified solution, and shake at 150 r / min for 2 hours. After completion, dry at 60° C. to obtain a modified polyurethane sponge filler.

[0074] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 393.90 g / cm 3 .

[0075] Comparative Example 1.1

[0076] Step S1: soaking the polyurethane sponge in a potassium persulfate solution with a mass concentration of 0.5wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0077] Step S2: At room temperature, add biochar powder (the mass ratio of biochar to polyurethane sponge matrix is ​​1:10) into 100 ml of deionized water and stir evenly, then immerse the polyurethane sponge matrix in the solution and shake at 150 r / min for 2 hours. After completion, dry at 60° C. to obtain a modified polyurethane sponge filler.

[0078] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 100.23 g / cm 3 .

[0079] Comparative Example 1.2

[0080] Step S1: soaking the polyurethane sponge in a potassium permanganate-concentrated sulfuric acid solution (the molar ratio of potassium permanganate to concentrated sulfuric acid is 1:3), and ultrasonically treating it at room temperature for 30 minutes; then washing it with a 0.1 mol / L hydrochloric acid solution and a 0.01 mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60° C. to obtain a polyurethane sponge matrix;

[0081] Step S2: At room temperature, add biochar powder (the mass ratio of biochar to polyurethane sponge matrix is ​​1:10) to 0.06 mol / L ferric chloride solution and stir evenly to obtain a modified solution. Immerse the polyurethane sponge matrix in the modified solution and shake at 150 r / min for 2 hours. After completion, dry at 60°C to obtain a modified polyurethane sponge filler.

[0082] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 307.33 g / cm 3 .

[0083] Comparative Example 1.3

[0084] Step S1: soaking the polyurethane sponge in a potassium persulfate solution with a mass concentration of 1.2wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0085] Step S2: immerse the polyurethane sponge matrix in a 0.06 mol / L ferric chloride solution and shake it at 150 r / min for 2 h; then immerse the polyurethane sponge matrix in a biochar powder modified solution (the mass ratio of biochar to polyurethane sponge matrix is ​​1:10) and shake it at 150 r / min for 2 h. After completion, dry it at 60° C. to obtain a modified polyurethane sponge filler.

[0086] According to the performance rating method described above, the modified polyurethane sponge filler has an ammonia adsorption capacity of 247.83 g / cm 3 .

[0087] Comparative Example 1.4

[0088] Step S1: soaking the polyurethane sponge in a glutaraldehyde solution with a mass concentration of 0.5wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively until the solution becomes neutral, taking it out, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0089] Step S2: At room temperature, add biochar powder (the mass ratio of biochar to polyurethane sponge matrix is ​​1:10) to 0.06 mol / L ferric chloride solution and stir evenly to obtain a modified solution. Immerse the polyurethane sponge matrix in the modified solution and shake at 150 r / min for 2 hours. After completion, dry at 60°C to obtain a modified polyurethane sponge filler.

[0090] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 228.06 g / cm 3 .

[0091] Comparative Example 1.5

[0092] Step S1: soaking the polyurethane sponge in a sodium hydroxide solution with a mass concentration of 0.5wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0093] Step S2: At room temperature, add biochar powder (the mass ratio of biochar to polyurethane sponge matrix is ​​1:10) to 0.06 mol / L ferric chloride solution and stir evenly to obtain a modified solution. Immerse the polyurethane sponge matrix in the modified solution and shake at 150 r / min for 2 hours. After completion, dry at 60°C to obtain a modified polyurethane sponge filler.

[0094] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 229.46 g / cm 3 .

[0095] Example 2.1

[0096] Step S1: soaking the polyurethane sponge in a potassium persulfate solution with a mass concentration of 0.5wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0097] Step S2: At room temperature, immerse the polyurethane sponge matrix in a 0.06 mol / L ferric chloride solution and shake at 150 r / min for 2 hours. After the shaking, dry at 60° C. to obtain a modified polyurethane sponge filler.

[0098] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 335.96 g / cm 3 .

[0099] Example 2.2

[0100] Step S1: soaking the polyurethane sponge in a potassium persulfate solution with a mass concentration of 0.5wt%, and ultrasonically treating it at room temperature for 30min; then washing it with a 0.1mol / L hydrochloric acid solution and a 0.01mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60°C to obtain a polyurethane sponge matrix;

[0101] Step S2: At room temperature, immerse the polyurethane sponge matrix in a 0.1 mol / L ferric chloride solution and shake at 150 r / min for 2 hours. After the shaking, dry at 60° C. to obtain a modified polyurethane sponge filler.

[0102] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 469.20 g / cm 3 .

[0103] Comparative Example 2.1

[0104] Step S1: soaking the polyurethane sponge in a potassium permanganate-concentrated sulfuric acid solution (the molar ratio of potassium permanganate to concentrated sulfuric acid is 1:3), and ultrasonically treating it at room temperature for 30 minutes; then washing it with a 0.1 mol / L hydrochloric acid solution and a 0.01 mol / L phosphate buffer solution for 3 times respectively, taking it out after the solution becomes neutral, and drying it at 60° C. to obtain a polyurethane sponge matrix;

[0105] Step S2: At room temperature, immerse the polyurethane sponge matrix in a 0.06 mol / L ferric chloride solution and shake at 150 r / min for 2 hours. After the shaking, dry at 60° C. to obtain a modified polyurethane sponge filler.

[0106] According to the performance rating method described in Example 1.1, the adsorption capacity of ammonia by the modified polyurethane sponge filler is 215.81 g / cm 3 .

[0107] The main preparation process conditions and the measured ammonia adsorption capacity of the modified polyurethane sponge fillers of each embodiment, comparative example, and unmodified control polyurethane sponge fillers are listed in Table 1. The ammonia adsorption capacity of the unmodified control polyurethane sponge filler is 61.39 g / cm 3 .

[0108] Table 1 Main preparation process conditions and ammonia adsorption capacity of different polyurethane sponge fillers

[0109]

[0110]

[0111] According to the above embodiments and comparative examples, the adsorption capacity of ammonia by the modified polyurethane sponge filler disclosed in the present invention is higher than that by the filler not modified by the method disclosed in the present invention. The above results all indicate that the adsorption performance of ammonia by the modified polyurethane sponge filler provided by the present invention reaches a very high level.

[0112] It can be seen from the above embodiments and comparative examples that the modified polyurethane sponge filler and preparation method for the treatment of malodorous gases in pig farms provided by the present invention have achieved good technical effects. The preparation method takes the polyurethane sponge filler as the matrix, firstly uses the peroxide disinfectant commonly used in pig farms as a strong oxidant to oxidatively corrode the polyurethane sponge filler, thereby improving the roughness of the surface and internal pore walls of the polyurethane sponge filler, increasing the specific surface area, and providing enough attachment points for the porous material; then the filler is immersed in a ferric chloride solution or a nickel chloride solution containing or not containing biochar powder for modification, and a modified polyurethane sponge filler is obtained after drying. The specific surface area of ​​the filler is further increased by using biochar adhesion modification and metal oxide adhesion modification such as iron oxide, thereby increasing the adsorption amount of gaseous pollutants by the polyurethane sponge filler and significantly improving the adsorption capacity for malodorous gases. The modified polyurethane sponge filler prepared by the present invention significantly improves the adsorption capacity of malodorous gases and improves the treatment efficiency of malodorous gases compared with traditional polyurethane sponge fillers; in addition, the common pig farm disinfectant is used as a modifier in the preparation method, which effectively solves the transportation problems caused by the closed management of the pig farm. At the same time, under the background of rising operating costs of pig farms, the modification method is simple and economical, which reduces the operating costs of pig farms.

[0113] Finally, it should be noted that, in the present disclosure, if any, relational terms such as first and second, etc., are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0114] Although the present disclosure has been disclosed above through the description of the specific embodiments of the present disclosure, it should be understood that those skilled in the art can design various modifications, improvements or equivalents to the present disclosure within the spirit and scope of the attached scheme. These modifications, improvements or equivalents should also be considered to be included in the scope of protection claimed by the present disclosure.

Claims

1. A method for preparing a modified polyurethane filler for odor control in aquaculture farms, characterized in that: include: Step S1: soaking the polyurethane sponge in a peroxide disinfectant for a first immersion treatment; Then, the solution is washed until it becomes neutral, taken out, and dried to obtain a polyurethane sponge matrix; Step S2: adding biochar powder to ferric chloride or nickel chloride solution, stirring evenly to obtain a modified solution; immersing the polyurethane sponge matrix in the modified solution for a second immersion treatment, and then drying to obtain a modified polyurethane sponge filler.

2. The method for preparing the modified polyurethane filler according to claim 1, characterized in that: In step S1, the peroxide disinfectant is a potassium persulfate solution; preferably, the mass concentration of the potassium persulfate solution is 0.5%-1.2%.

3. The method for preparing the modified polyurethane filler according to claim 1 or 2, characterized in that: In step S1, the first immersion treatment is performed simultaneously with ultrasonic treatment, the temperature of the ultrasonic treatment is room temperature, the time is 15-30 minutes, and the ultrasonic power is 200-240W.

4. The method for preparing the modified polyurethane filler according to any one of claims 1 to 3, characterized in that: In step S1, the washing treatment is washing 2 to 3 times with 0.1 mol / L hydrochloric acid solution and 0.01 mol / L phosphate buffer respectively; Optionally, in step S1, the drying process is performed at a temperature of 60-80°C.

5. The method for preparing the modified polyurethane filler according to any one of claims 1 to 4, characterized in that: In step S2, the mass ratio of the biochar powder to the polyurethane sponge matrix is ​​1:5-10; Optionally, in step S2, the particle size of the biochar powder is less than 75 μm, preferably 35-75 μm; Optionally, in step S2, the biochar powder is soaked in a 1 mol / L hydrochloric acid solution for 8 hours before use, filtered, washed with deionized water, and dried.

6. The method for preparing the modified polyurethane filler according to any one of claims 1 to 5, characterized in that: In step S2, the concentration of the ferric chloride solution or the nickel chloride solution is 0.05-0.2 mol / L, preferably 0.06-0.1 mol / L.

7. The method for preparing the modified polyurethane filler according to any one of claims 1 to 6, characterized in that: In step S2, the second immersion treatment is performed while an oscillation treatment is performed; the rotation speed of the oscillation treatment is 120-180 r / min, and the oscillation time is 1-3 h; Optionally, in step S2, the drying process is performed at a temperature of 60-80°C.

8. The method for preparing the modified polyurethane filler according to any one of claims 1 to 7, characterized in that: In step S2, the addition of biochar powder is omitted, and ferric chloride or nickel chloride solution is directly used as the modification solution.

9. A modified polyurethane sponge filler, characterized in that it is prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the modified polyurethane sponge filler as claimed in claim 9 in the treatment of malodorous gases in breeding farms, wherein the breeding farm is preferably a pig farm.

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