Biological deodorant carrier and preparation method thereof

Abstract

The invention provides a biological deodorant carrier and a preparation method thereof, and belongs to the technical field of biological deodorant carriers, the preparation method comprises the following steps: preparing hydroxyapatite, preparing modified hydroxyapatite, preparing a polyurethane prepolymer emulsion, and preparing a hydroxyapatite / polyurethane compound; the method for preparing the hydroxyapatite / polyurethane compound comprises the following steps: adding modified hydroxyapatite into a polyurethane prepolymer emulsion, stirring and reacting for 0.7-1.2 hours, and then drying and crushing to obtain the hydroxyapatite / polyurethane compound. The load capacity of the biological deodorant carrier to microorganisms is 2.1-2.5%, the stability of the biological deodorant carrier is high, the hydrogen sulfide removal efficiency is still 87.1-89.5% within 48-54 hours, the ammonia gas removal efficiency is still 87.2-90.1%, the biological deodorant carrier can accelerate the deodorization efficiency, and the hydrogen sulfide removal efficiency is 95.1-97.6% and the ammonia gas removal efficiency is 95.9-98.1% within 24 hours.

Description

Technical Field

[0001] The invention belongs to the technical field of biological deodorant carriers, and particularly relates to a biological deodorant carrier and a preparation method thereof. Background Art

[0002] Biological deodorants are environmentally friendly and highly efficient deodorizing products. In recent years, they have been widely used in daily life, agriculture, industry and other fields. Biological deodorants can eliminate odors and improve air quality by inhibiting, decomposing and transforming odorous substances (such as hydrogen sulfide, mercaptans and ammonia). At present, biological deodorants are mainly divided into two categories: microorganisms (such as Bacillus, photosynthetic bacteria, nitrifying bacteria, etc.) and enzymes (such as proteases, amylases, etc.). However, biological deodorants have many common problems: biological activity is greatly affected by the environment, the durability is low, and the effect is slow.

[0003] Using carriers to load biological deodorants can effectively reduce the impact of the environment on biological activity, increase the durability of biological deodorants, and improve the rate of effectiveness.

[0004] Patent CN110201204B discloses a biological deodorant carrier and a preparation method thereof, a biological deodorant and a preparation method thereof. In the technical scheme, the preparation method of the biological deodorant carrier is: clay, attapulgite powder, calcium carbonate, silicon dioxide and water are mixed, and then molded to obtain wet spherical particles. The wet spherical particles are aged and then roasted to obtain the biological deodorant carrier. The biological deodorant carrier is easy to obtain, relatively low in cost, non-toxic to microorganisms, chemically stable, and not easily decomposed by microorganisms. However, the biological deodorant carrier lacks the initial nutrients required by microorganisms and has a low load on microorganisms.

[0005] Patent CN118460436B discloses a microbial deodorant and a production process thereof. In the technical solution, biochar is used as a substrate, glutaraldehyde is used as a cross-linking agent, β-cyclodextrin and modified polyaspartic acid are loaded on the biochar, and a biological deodorant carrier is prepared. The biological deodorant carrier has a good void structure and a large specific surface area, and can provide a suitable habitat for microorganisms. The technical solution introduces that the modified polyaspartic acid has the function of adsorbing and enriching odor molecules, and has a polypeptide main chain structure similar to protein, and can serve as a nutrient for the growth of microorganisms. However, when the microorganisms degrade the modified polyaspartic acid to absorb nutrients, it will affect the modified polyaspartic acid's adsorption and enrichment of odor molecules, thereby resulting in reduced durability of the carrier and reduced deodorization efficiency. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides a biological deodorant carrier and a preparation method thereof, so as to achieve the following invention objectives: while increasing the carrier's loading capacity for microorganisms and providing the nutrients required for microbial growth, the carrier's durability is improved and the deodorization efficiency is enhanced.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: A biological deodorant carrier and a preparation method thereof, comprising the following steps: 1. Preparation of hydroxyapatite The pH value of the Na2HPO4 solution is adjusted to 10.5-11.5 using a NaOH solution to obtain an alkaline Na2HPO4 solution, and a mixed solution of the CaCl2 solution and the sodium dodecyl sulfate solution is slowly dripped into the alkaline Na2HPO4 solution, and the stirring rate is maintained at 60-90 r / min during the dripping process. After the dripping is completed, NaHCO3 powder is added, and then transferred to a hydrothermal kettle, and the reaction is carried out at a constant temperature of 90-110°C for 7-9h, cooled to room temperature, washed with distilled water and ethanol for 2-4 times each, and then dried in a drying oven at 70-90°C for 5-7h, and crushed into a powder of 0.06-0.12mm to obtain hydroxyapatite; The mass fraction of the NaOH solution is 3-5%; The mass fraction of the Na2HPO4 solution is 5.1-5.5%; The mass fraction of the CaCl2 solution is 23.2-23.9%; The mass fraction of the sodium dodecyl sulfate solution is 6 to 7%; The dropping time is 20 to 40 minutes; The mass ratio of the Na2HPO4 solution, the CaCl2 solution, the sodium dodecyl sulfate solution and the NaHCO3 powder is 12-14: 3.01-3.09: 0.5-0.7: 0.34-0.38.

[0008] 2. Preparation of modified hydroxyapatite The hydroxyapatite is completely immersed in a vitamin E solution, and after 12 to 18 minutes, it is added to a mixed solution of a soybean protein solution and a sodium alginate solution, stirred at a rate of 50 to 70 r / min for 15 to 25 minutes, and dried in a drying oven at 35 to 45° C. for 1.5 to 2.5 hours to obtain modified hydroxyapatite; The mass fraction of the vitamin E solution is 8 to 12%; The mass fraction of the soybean protein solution is 17.5-18.1%; The mass fraction of the sodium alginate solution is 23.3-23.7%; The mass ratio of the hydroxyapatite, the vitamin E solution, the soybean protein solution and the sodium alginate solution is 5.1-5.3:7.4-7.7:8.35-8.39:10-14.

[0009] 3. Preparation of polyurethane prepolymer emulsion The polybutylene glycol is heated to 70-80° C. in a water bath, and then isophorone diisocyanate is added, and the reaction is continued for 1.5-2.5 hours. After adding a catalyst dibutyltin dilaurate and continuing the reaction for 0.3-0.7 hours, the water bath temperature is reduced to 45-55° C., and a hydrophilic chain extender diethylenetriamine is added to react for 30-45 minutes, and the water bath temperature is increased to 80-90° C., and a bio-based chain extender is added, and the reaction is stirred for 0.7-1.3 hours, and the water bath temperature is reduced to 60-70° C., and a capping agent 4-tert-butylphenol is added, and the reaction is stirred for 1.5-2.5 hours, and the water bath temperature is reduced to 30-50° C., and deionized water is added at a stirring rate of 700-900 r / min, and emulsification is performed for 10-20 minutes to obtain a polyurethane prepolymer emulsion; The molecular weight of the polybutylene glycol is 1000 to 3000; The stirring reaction rate is 450-550 r / min; The mass ratio of the polybutylene glycol, isophorone diisocyanate, dibutyltin dilaurate, diethylenetriamine, bio-based chain extender, 4-tert-butylphenol, and deionized water is 20-30: 8.1-8.2: 0.89-0.96: 2.45-2.52: 1.91-1.96: 2.5-2.6: 6.36-6.42; The preparation method of the bio-based chain extender comprises adding pentaerythritol to lactic acid, adding a catalyst ZnCl2 in a water bath at 50-70° C., reacting for 4-7 hours, washing the product with a saturated Na2CO3 solution, and then drying at 25-35° C. for 15-25 minutes to obtain the bio-based chain extender; The mass ratio of pentaerythritol, lactic acid and ZnCl2 is 15-19:40-50:1.3-1.8.

[0010] 4. Preparation of hydroxyapatite / polyurethane composite The modified hydroxyapatite is added to the polyurethane prepolymer emulsion, stirred at a stirring rate of 80 to 120 r / min for 0.7 to 1.2 hours, then placed in a vacuum drying oven at 40 to 60° C. for 7 to 9 hours, and crushed into particles with a particle size of 2 to 4 cm to obtain a hydroxyapatite / polyurethane composite, i.e., a biological deodorant carrier; The mass ratio of the modified hydroxyapatite to the polyurethane prepolymer emulsion is 1.1-1.5:2.72-2.78.

[0011] Compared with the prior art, the present invention has the following beneficial effects: 1. The biological deodorant carrier of the present invention, when preparing hydroxyapatite, adds sodium dodecyl sulfate solution to improve the dispersibility of hydroxyapatite; adds NaHCO3 powder, and the CO2 generated by the NaHCO3 powder can increase the porosity and specific surface area of ​​hydroxyapatite.

[0012] 2. The biological deodorant carrier of the present invention, when preparing modified hydroxyapatite, vitamin E cross-links soybean protein and sodium alginate and is adsorbed on the surface of hydroxyapatite to obtain modified hydroxyapatite. The modified hydroxyapatite contains basic nutrients required for microbial reproduction and has a strong affinity for microorganisms.

[0013] 3. The biological deodorant carrier of the present invention is prepared by adding a hydrophilic chain extender diethylenetriamine and a bio-based chain extender when preparing a polyurethane prepolymer emulsion. Diethylenetriamine not only improves the hydrophilicity of the carrier, but also introduces an amine group on the surface of the carrier, which has a strong affinity for odor molecules such as hydrogen sulfide, thereby achieving odor enrichment and providing a favorable place for microbial decomposition. The bio-based chain extender is obtained by esterifying pentaerythritol with lactic acid. The bio-based chain extender contains 4 lactic acid chains, which can connect long polyurethane chains from 4 directions to form more network structures. Therefore, the final carrier has more porous structures and a more stable structure, which further enhances the enrichment of odor.

[0014] 4. The biological deodorant carrier of the present invention has a loading capacity of 2.1-2.5% for microorganisms. The biological deodorant carrier has high stability and can carry microorganisms for continuous deodorization for 48-54 hours. At 48-54 hours, the efficiency of hydrogen sulfide removal is still 87.1-89.5%, and the efficiency of ammonia removal is still 87.2-90.1%. The biological deodorant carrier can accelerate the deodorization efficiency. Within 24 hours, the efficiency of hydrogen sulfide removal is 95.1-97.6%, and the efficiency of ammonia removal is 95.9-98.1%. DETAILED DESCRIPTION

[0015] Example 1 A method for preparing a biological deodorant carrier comprises the steps of preparing hydroxyapatite, preparing modified hydroxyapatite, preparing polyurethane prepolymer emulsion and preparing hydroxyapatite / polyurethane composite.

[0016] 1. Preparation of hydroxyapatite The pH value of the Na2HPO4 solution was adjusted to 11 using a NaOH solution to obtain an alkaline Na2HPO4 solution, and a mixed solution of the CaCl2 solution and the sodium dodecyl sulfate solution was slowly dripped into the alkaline Na2HPO4 solution, and the stirring rate was maintained at 80 r / min during the dripping process. After the dripping was completed, NaHCO3 powder was added, and then transferred to a hydrothermal kettle, and the reaction was carried out at a constant temperature of 100°C for 8 hours, cooled to room temperature, washed with distilled water and ethanol for 3 times each, and then dried in a drying oven at 80°C for 6 hours, and crushed into a powder of 0.08-0.10 mm to obtain hydroxyapatite; The mass fraction of the NaOH solution is 4%; The mass fraction of the Na2HPO4 solution is 5.3%; The mass fraction of the CaCl2 solution is 23.6%; The mass fraction of the sodium dodecyl sulfate solution is 6.5%; The dropping time is 30min; The mass ratio of the Na2HPO4 solution, the CaCl2 solution, the sodium dodecyl sulfate solution and the NaHCO3 powder is 13:3.06:0.6:0.36.

[0017] 2. Preparation of modified hydroxyapatite The hydroxyapatite was completely immersed in the vitamin E solution, and after 15 minutes, it was added into the mixed solution of the soybean protein solution and the sodium alginate solution, stirred at a rate of 60 r / min for 20 minutes, and dried in a drying oven at 40°C for 2 hours to obtain the modified hydroxyapatite; The mass fraction of the vitamin E solution is 10%; The mass fraction of the soybean protein solution is 17.8%; The mass fraction of the sodium alginate solution is 23.5%; The mass ratio of the hydroxyapatite, the vitamin E solution, the soybean protein solution and the sodium alginate solution is 5.2:7.6:8.37:12.

[0018] 3. Preparation of polyurethane prepolymer emulsion Heat polybutylene glycol to 75°C in a water bath, then add isophorone diisocyanate, react for 2 hours, add catalyst dibutyltin dilaurate and continue to react for 0.5 hours, then reduce the water bath temperature to 50°C, add hydrophilic chain extender diethylenetriamine and react for 38 minutes, then increase the water bath temperature to 85°C, add bio-based chain extender, react for 1 hour at a stirring rate of 500 r / min, then reduce the water bath temperature to 65°C, add end-capping agent 4-tert-butylphenol, react for 2 hours at a stirring rate of 500 r / min, then reduce the water bath temperature to 40°C, add deionized water at a stirring rate of 800 r / min, emulsify for 15 minutes, and obtain a polyurethane prepolymer emulsion; The molecular weight of the polybutylene glycol is 2000; The mass ratio of the polybutylene glycol, isophorone diisocyanate, dibutyltin dilaurate, diethylenetriamine, bio-based chain extender, 4-tert-butylphenol, and deionized water is 25:8.16:0.93:2.48:1.94:2.55:6.39; The preparation method of the bio-based chain extender comprises adding pentaerythritol to lactic acid, adding a catalyst ZnCl2 in a water bath at 60°C, reacting for 5 hours, washing the product with a saturated Na2CO3 solution, and then drying at 30°C for 20 minutes to obtain the bio-based chain extender; The mass ratio of pentaerythritol, lactic acid and ZnCl2 is 17:45:1.6.

[0019] 4. Preparation of hydroxyapatite / polyurethane composite The modified hydroxyapatite was added to the polyurethane prepolymer emulsion, stirred at a stirring rate of 100 r / min for 1 hour, then placed in a vacuum drying oven at 50°C for 8 hours, and crushed into particles with a particle size of 3 cm to obtain a hydroxyapatite / polyurethane composite, i.e., a biological deodorant carrier; The mass ratio of the modified hydroxyapatite to the polyurethane prepolymer emulsion is 1.3:2.75.

[0020] Example 2 A method for preparing a biological deodorant carrier comprises the steps of preparing hydroxyapatite, preparing modified hydroxyapatite, preparing polyurethane prepolymer emulsion and preparing hydroxyapatite / polyurethane composite.

[0021] 1. Preparation of hydroxyapatite The pH value of the Na2HPO4 solution was adjusted to 10.5 using a NaOH solution to obtain an alkaline Na2HPO4 solution, and a mixed solution of the CaCl2 solution and the sodium dodecyl sulfate solution was slowly dripped into the alkaline Na2HPO4 solution, and the stirring rate was maintained at 60 r / min during the dripping process. After the dripping was completed, NaHCO3 powder was added, and then transferred to a hydrothermal kettle, and the reaction was carried out at a constant temperature of 90°C for 7 hours, cooled to room temperature, washed with distilled water and ethanol twice each, and then dried in a drying oven at 70°C for 5 hours, and crushed into a powder of 0.06-0.08 mm to obtain hydroxyapatite; The mass fraction of the NaOH solution is 3%; The mass fraction of the Na2HPO4 solution is 5.1%; The mass fraction of the CaCl2 solution is 23.2%; The mass fraction of the sodium dodecyl sulfate solution is 6%; The dropping time is 20min; The mass ratio of the Na2HPO4 solution, the CaCl2 solution, the sodium dodecyl sulfate solution and the NaHCO3 powder is 12:3.01:0.5:0.34.

[0022] 2. Preparation of modified hydroxyapatite The hydroxyapatite was completely immersed in the vitamin E solution, and after 12 minutes, it was added into the mixed solution of the soybean protein solution and the sodium alginate solution, stirred at a rate of 50 r / min for 15 minutes, and dried in a drying oven at 35°C for 1.5 hours to obtain the modified hydroxyapatite; The mass fraction of the vitamin E solution is 8%; The mass fraction of the soybean protein solution is 17.5%; The mass fraction of the sodium alginate solution is 23.3%; The mass ratio of the hydroxyapatite, the vitamin E solution, the soybean protein solution and the sodium alginate solution is 5.1:7.4:8.35:10.

[0023] 3. Preparation of polyurethane prepolymer emulsion Heat polybutylene glycol to 70°C in a water bath, then add isophorone diisocyanate, react for 1.5 hours, add catalyst dibutyltin dilaurate and continue to react for 0.3 hours, then reduce the water bath temperature to 45°C, add hydrophilic chain extender diethylenetriamine and react for 30 minutes, then increase the water bath temperature to 80°C, add bio-based chain extender, react for 0.7 hours at a stirring rate of 450 r / min, then reduce the water bath temperature to 60°C, add end-capping agent 4-tert-butylphenol, react for 1.5 hours at a stirring rate of 450 r / min, then reduce the water bath temperature to 30°C, add deionized water at a stirring rate of 700 r / min, emulsify for 10 minutes, and obtain a polyurethane prepolymer emulsion; The molecular weight of the polybutylene glycol is 1000; The mass ratio of the polybutylene glycol, isophorone diisocyanate, dibutyltin dilaurate, diethylenetriamine, bio-based chain extender, 4-tert-butylphenol, and deionized water is 20:8.1:0.89:2.45:1.91:2.5:6.36; The preparation method of the bio-based chain extender comprises adding pentaerythritol to lactic acid, adding a catalyst ZnCl2 in a water bath at 50°C, reacting for 4 hours, washing the product with a saturated Na2CO3 solution, and then drying at 25°C for 15 minutes to obtain the bio-based chain extender; The mass ratio of pentaerythritol, lactic acid and ZnCl2 is 15:40:1.3.

[0024] 4. Preparation of hydroxyapatite / polyurethane composite The modified hydroxyapatite was added to the polyurethane prepolymer emulsion, stirred at a stirring rate of 80 r / min for 0.7 h, then placed in a vacuum drying oven at 40° C. for 7 h, and crushed into particles with a particle size of 2 cm to obtain a hydroxyapatite / polyurethane composite, i.e., a biological deodorant carrier; The mass ratio of the modified hydroxyapatite to the polyurethane prepolymer emulsion is 1.1:2.72.

[0025] Example 3 A method for preparing a biological deodorant carrier comprises the steps of preparing hydroxyapatite, preparing modified hydroxyapatite, preparing polyurethane prepolymer emulsion and preparing hydroxyapatite / polyurethane composite.

[0026] 1. Preparation of hydroxyapatite The pH value of the Na2HPO4 solution was adjusted to 11.5 using a NaOH solution to obtain an alkaline Na2HPO4 solution, and a mixed solution of the CaCl2 solution and the sodium dodecyl sulfate solution was slowly dripped into the alkaline Na2HPO4 solution, and the stirring rate was maintained at 90 r / min during the dripping process. After the dripping was completed, NaHCO3 powder was added, and then transferred to a hydrothermal kettle, and the reaction was carried out at a constant temperature of 110°C for 9 hours, cooled to room temperature, washed with distilled water and ethanol for 4 times each, and then dried in a drying oven at 90°C for 7 hours, and crushed into a powder of 0.10-0.12 mm to obtain hydroxyapatite; The mass fraction of the NaOH solution is 5%; The mass fraction of the Na2HPO4 solution is 5.5%; The mass fraction of the CaCl2 solution is 23.9%; The mass fraction of the sodium dodecyl sulfate solution is 7%; The dropping time is 40min; The mass ratio of the Na2HPO4 solution, the CaCl2 solution, the sodium dodecyl sulfate solution and the NaHCO3 powder is 14:3.09:0.7:0.38.

[0027] 2. Preparation of modified hydroxyapatite The hydroxyapatite was completely immersed in the vitamin E solution, and after 18 minutes, it was added into the mixed solution of the soybean protein solution and the sodium alginate solution, stirred at a rate of 70 r / min for 25 minutes, and dried in a drying oven at 45°C for 2.5 hours to obtain the modified hydroxyapatite; The mass fraction of the vitamin E solution is 12%; The mass fraction of the soybean protein solution is 18.1%; The mass fraction of the sodium alginate solution is 23.7%; The mass ratio of the hydroxyapatite, the vitamin E solution, the soybean protein solution and the sodium alginate solution is 5.3:7.7:8.39:14.

[0028] 3. Preparation of polyurethane prepolymer emulsion The polybutylene glycol was heated to 80°C in a water bath, and then isophorone diisocyanate was added. After reacting for 2.5 hours, a catalyst dibutyltin dilaurate was added and the reaction was continued for 0.7 hours. The water bath temperature was lowered to 55°C, and a hydrophilic chain extender diethylenetriamine was added and reacted for 45 minutes. The water bath temperature was raised to 90°C, and a bio-based chain extender was added. After reacting for 1.3 hours at a stirring rate of 550 r / min, the water bath temperature was lowered to 70°C, and a capping agent 4-tert-butylphenol was added. After reacting for 2.5 hours at a stirring rate of 550 r / min, the water bath temperature was lowered to 50°C. Deionized water was added at a stirring rate of 900 r / min, and emulsified for 20 minutes to obtain a polyurethane prepolymer emulsion. The mass ratio of the polybutylene glycol, isophorone diisocyanate, dibutyltin dilaurate, diethylenetriamine, bio-based chain extender, 4-tert-butylphenol, and deionized water is 30:8.2:0.96:2.52:1.96:2.6:6.42; The preparation method of the bio-based chain extender comprises adding pentaerythritol to lactic acid, adding a catalyst ZnCl2 in a water bath at 70°C, reacting for 7 hours, washing the product with a saturated Na2CO3 solution, and then drying at 35°C for 25 minutes to obtain the bio-based chain extender; The mass ratio of pentaerythritol, lactic acid and ZnCl2 is 19:50:1.8.

[0029] 4. Preparation of hydroxyapatite / polyurethane composite The modified hydroxyapatite was added to the polyurethane prepolymer emulsion, stirred at a stirring rate of 120 r / min for 1.2 h, then placed in a vacuum drying oven at 60° C. for 9 h, and crushed into particles with a particle size of 4 cm to obtain a hydroxyapatite / polyurethane composite, i.e., a biological deodorant carrier; The mass ratio of the modified hydroxyapatite to the polyurethane prepolymer emulsion is 1.5:2.78.

[0030] Comparative Example 1 The same biological deodorant carrier and preparation method as in Example 1 are used, except that the preparation of modified hydroxyapatite in step 2 is omitted, and the modified hydroxyapatite in step 4 is replaced by hydroxyapatite.

[0031] Comparative Example 2 The same biological deodorant carrier and preparation method as in Example 1 are used, except that the addition of the biological chain extender in step 3 is omitted. Specifically, polybutylene glycol is melted in a water bath at 75°C, and then isophorone diisocyanate is added. After reacting for 2 hours, a catalyst dibutyltin dilaurate is added and the reaction is continued for 0.5 hours. The water bath temperature is then lowered to 50°C, a hydrophilic chain extender diethylenetriamine is added and reacted for 38 minutes, the water bath temperature is raised to 65°C, a capping agent 4-tert-butylphenol is added, and the reaction is carried out at a stirring rate of 500 r / min for 2 hours. The water bath temperature is then lowered to 40°C, and deionized water is added at a stirring rate of 800 r / min. The mixture is emulsified for 15 minutes to obtain a polyurethane prepolymer emulsion.

[0032] Comparative Example 3 The same biological deodorant carrier and preparation method as in Example 1 are used, except that the preparation of the polyurethane prepolymer emulsion in step 3 is omitted, and the modified hydroxyapatite obtained in step 2 is the biological deodorant carrier.

[0033] Test Example 1 The loading capacity of the bio-deodorant carriers prepared in Examples 1 to 3 and Comparative Examples 1 to 3 on microorganisms (bio-deodorants) was tested, and the test method was as follows: (1) Add acetic acid bacteria, Bacillus bacteria, and Alcaligenes faecalis bacteria into a mixer at a mass ratio of 3:5:2, and stir at 200 r / min for 20 min to obtain the biological deodorant bacterial solution used in this test; The preparation method of the acetobacillus agent is to dissolve acetobacillus in water and prepare the acetobacillus content to be 1.5×10 7 CFU / mL of Acetobacter inoculum; The preparation method of the bacillus agent is to dissolve the bacillus in water and prepare the bacillus content to be 3.5×10 8 CFU / mL of Bacillus inoculants; The preparation method of the alcaligenes faecalis agent is to dissolve the alcaligenes faecalis in water and prepare the alcaligenes faecalis agent to have a content of 2.5×10 9 CFU / mL of Alcaligenes faecalis inoculum; (2) Weigh the biological deodorant carrier, denoted as m1, soak it in the biological deodorant bacterial solution used in this test, stir it at a speed of 300 r / min for 20 min, take out the biological deodorant carrier, drain it in the air until there are no water droplets on the surface, weigh it, and then soak it in the biological deodorant bacterial solution again. Repeat the soaking-draining-weighing steps according to the above steps until the mass difference obtained by three consecutive weighings does not exceed ±0.02g, and obtain a saturated biological deodorant carrier. Dry the saturated biological deodorant carrier at 30°C for 16 h to obtain a dried saturated biological deodorant carrier, denoted as m2; Then the loading amount of the biological deodorant carrier = (m2-m1) / m1×100%; The test results are shown in Table 1.

[0034] Table 1

[0035] Test Example 2 The deodorization efficiency (efficiency of removing hydrogen sulfide and ammonia) of the biological deodorant carriers prepared in Examples 1 to 3 and Comparative Examples 1 to 3 was tested, and the test method was as follows: Efficiency of hydrogen sulfide removal: Weigh 10 g of the dried saturated biological deodorant carrier prepared in Test Example 1, put it into a large bubble straw, and introduce an initial concentration of 0.15 mg / m at a flow rate of 1 L / min under normal temperature (20°C) and normal pressure (1 standard atmosphere). 3 15L hydrogen sulfide gas was added, and the gas was circulated for 24h, 30h, 36h, 42h, 48h, and 54h, and the gas before and after treatment was collected, and the concentration of hydrogen sulfide was analyzed according to GB / T11742; The efficiency of hydrogen sulfide removal is x = (b0-b) / b0×100%; Where: b0 is the concentration of hydrogen sulfide before treatment, mg / m 3 , b is the concentration of hydrogen sulfide after treatment, mg / m 3 .

[0036] Ammonia removal efficiency: Weigh 10 g of the dried saturated biological deodorant carrier prepared in Test Example 1, put it into a large bubble straw, and introduce an initial concentration of 1.5 mg / m at a flow rate of 1 L / min under normal temperature (20°C) and normal pressure (1 standard atmosphere). 3 15L ammonia gas was added, and the gas was circulated for 24h, 30h, 36h, 42h, 48h, and 54h, and the gas before and after treatment was collected, and the concentration of ammonia was analyzed according to HJ533; Ammonia removal efficiency y = (c0-c) / c0×100%; Where: c0 is the concentration of ammonia before treatment, mg / m 3 , c is the concentration of ammonia after treatment, mg / m 3 .

[0037] The test results are shown in Table 2.

[0038] Table 2

[0039] It can be seen from the above results that compared with Comparative Examples 1, 2, and 3, Example 1 has a higher loading amount of the biological deodorant bacterial liquid and a longer deodorizing time. At 48 to 54 hours, the efficiency of removing hydrogen sulfide and ammonia is higher than 85%, and the efficiency of removing hydrogen sulfide and ammonia is high; Furthermore, in Comparative Example 1, hydroxyapatite was not modified, hydroxyapatite was easy to agglomerate, and the surface of hydroxyapatite lacked the protein required for microbial reproduction, which resulted in a low loading amount of the biological deodorant bacterial solution, and thus resulted in low efficiency of hydrogen sulfide and ammonia removal and low deodorization persistence. At 36 to 42 hours, the efficiency of hydrogen sulfide and ammonia removal began to drop significantly; Comparative Example 2 did not add a biological chain extender, which resulted in a reduction in the pore structure on the surface of the biological deodorant carrier, resulting in a low loading amount of the biological deodorant bacterial solution, low efficiency in removing hydrogen sulfide and ammonia, and low deodorization persistence; Comparative Example 3 uses modified hydroxyapatite as a biological deodorant carrier, and the loaded biological deodorant bacterial liquid is mostly on the surface of the carrier, lacking the protection of polyurethane and the adsorption of polyurethane on the biological deodorant bacterial liquid. Therefore, the loading amount of the biological deodorant bacterial liquid is low, the efficiency of removing hydrogen sulfide and ammonia is low, and the deodorization persistence is low.

Claims

1. A method for preparing a biological deodorant carrier, characterized in that: The preparation method includes preparing hydroxyapatite, preparing modified hydroxyapatite, preparing polyurethane prepolymer emulsion, and preparing hydroxyapatite / polyurethane composite; The method for preparing modified hydroxyapatite is as follows: immersing hydroxyapatite completely in a vitamin E solution for 12 to 18 minutes, adding the solution to a mixed solution of a soybean protein solution and a sodium alginate solution, stirring the solution for 15 to 25 minutes, and drying the solution to obtain the modified hydroxyapatite; The method for preparing the polyurethane prepolymer emulsion comprises the following steps: heating polybutylene glycol to 70-80° C. in a water bath, then adding isophorone diisocyanate, reacting for 1.5-2.5 hours, adding dibutyltin dilaurate and continuing the reaction for 0.3-0.7 hours, reducing the water bath temperature to 45-55° C., adding diethylenetriamine and reacting for 30-45 minutes, raising the water bath temperature to 80-90° C., adding a bio-based chain extender, stirring and reacting for 0.7-1.3 hours, reducing the water bath temperature to 60-70° C., adding 4-tert-butylphenol, stirring and reacting for 1.5-2.5 hours, reducing the water bath temperature to 30-50° C., adding deionized water at a stirring rate of 700-900 r / min, emulsifying for 10-20 minutes, and obtaining the polyurethane prepolymer emulsion.

2. The method for preparing a biological deodorant carrier according to claim 1, characterized in that: In the method for preparing modified hydroxyapatite, the mass ratio of hydroxyapatite, vitamin E solution, soybean protein solution and sodium alginate solution is 5.1-5.3:7.4-7.7:8.35-8.39:10-14; the mass fraction of vitamin E solution is 8-12%; the mass fraction of soybean protein solution is 17.5-18.1%; and the mass fraction of sodium alginate solution is 23.3-23.7%.

3. The method for preparing a biological deodorant carrier according to claim 1, characterized in that: In the method for preparing the polyurethane prepolymer emulsion, the mass ratio of polybutylene glycol, isophorone diisocyanate, dibutyltin dilaurate, diethylenetriamine, bio-based chain extender, 4-tert-butylphenol and deionized water is 20-30:8.1-8.2:0.89-0.96:2.45-2.52:1.91-1.96:2.5-2.6:6.36-6.42; the molecular weight of polybutylene glycol is 1000-3000.

4. The method for preparing a biological deodorant carrier according to claim 1, characterized in that: In the method for preparing the polyurethane prepolymer emulsion, the preparation method of the bio-based chain extender is to add pentaerythritol to lactic acid, add a catalyst ZnCl2 in a water bath at 50-70°C, react for 4-7 hours, wash the product with a saturated Na2CO3 solution, and then dry it to obtain the bio-based chain extender.

5. The method for preparing a biological deodorant carrier according to claim 4, characterized in that: In the preparation method of the bio-based chain extender, the mass ratio of pentaerythritol, lactic acid and ZnCl2 is 15-19:40-50:1.3-1.

8.

6. The method for preparing a biological deodorant carrier according to claim 1, characterized in that: The method for preparing the hydroxyapatite / polyurethane composite is to add modified hydroxyapatite into polyurethane prepolymer emulsion, stir for 0.7 to 1.2 hours at a stirring rate of 80 to 120 r / min, and then dry and crush to obtain the hydroxyapatite / polyurethane composite, i.e., the biological deodorant carrier.

7. The method for preparing a biological deodorant carrier according to claim 6, characterized in that: In the method for preparing the hydroxyapatite / polyurethane composite, the mass ratio of the modified hydroxyapatite to the polyurethane prepolymer emulsion is 1.1-1.5:2.72-2.

78.

8. The method for preparing a biological deodorant carrier according to claim 1, characterized in that: The method for preparing hydroxyapatite comprises the following steps: adjusting the pH value of a Na2HPO4 solution to 10.5-11.5 using a NaOH solution to obtain an alkaline Na2HPO4 solution, slowly dropping a mixed solution of a CaCl2 solution and a sodium dodecyl sulfate solution into the alkaline Na2HPO4 solution, adding NaHCO3 powder after the dropping is complete, and then transferring the mixture to a hydrothermal kettle, reacting the mixture at a constant temperature of 90-110° C. for 7-9 hours, and obtaining hydroxyapatite after cooling, washing, drying, and crushing.

9. The method for preparing a biological deodorant carrier according to claim 8, characterized in that: In the method for preparing hydroxyapatite, the mass ratio of Na2HPO4 solution, CaCl2 solution, sodium dodecyl sulfate solution and NaHCO3 powder is 12-14: 3.01-3.09: 0.5-0.7: 0.34-0.38; the mass fraction of NaOH solution is 3-5%; the mass fraction of Na2HPO4 solution is 5.1-5.5%; the mass fraction of CaCl2 solution is 23.2-23.9%; the mass fraction of sodium dodecyl sulfate solution is 6-7%; and the dripping time is 20-40 minutes.

10. The biological deodorant carrier prepared by the preparation method according to any one of claims 1 to 9.

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