A method for promoting the degradation of penicillin antibiotics in water

Abstract

The invention discloses a method for promoting the degradation of penicillin antibiotics in water, comprising: S1, water quality detection; S2, medium adjustment; S3, catalytic degradation; S4, precipitation reaction. The invention uses calcium ions and organic matter to adjust the medium of the water to be treated, so that the water to be treated can be in a good state. The calcium ions can coordinate with the carbonyl and carboxyl groups in the penicillin molecules, stabilize the hydrolysis reaction intermediates, and accelerate the hydrolysis rate of the penicillin antibiotics. The characteristic functional groups such as amino groups and thiol groups in the biological metabolic organic matter can also serve as strong nucleophilic reagents to promote the rapid hydrolysis of the penicillin antibiotics. At the same time, through the specific setting of the method, it is possible to avoid secondary pollution of the water to be treated by calcium ions and biological organic metabolic media before degradation.

Description

Technical Field

[0001] The invention relates to the technical field of water treatment, in particular to a method for promoting the degradation of penicillin antibiotics in water. Background Art

[0002] Penicillin G (PG), an important broad-spectrum penicillin antibiotic, has been widely used to prevent and treat human and livestock diseases. However, penicillin antibiotics have a short half-life in vivo, and most of the parent antibiotic is excreted through the body's circulation in urine and feces, and discharged into environmental water bodies. For example, Clarke's research showed that 30% of oral and 75% of intravenous ampicillin parenterals are not absorbed by the body and are directly excreted in the urine (Mitchell et al. 2014). In addition, a large number of precursors of various antibiotics such as penicillin are also present in untreated wastewater from pharmaceutical companies, which can also enter environmental water bodies through sewage; the discharge of penicillin G and other antibiotics into water bodies may cause bacteria to develop drug resistance, which not only affects the efficacy of antibiotics, but may also lead to an increase in difficult-to-treat infections. At the same time, it destroys the ecological balance. The presence of antibiotics may interfere with the normal physiological functions of aquatic organisms, affect their growth and reproduction, and thus destroy the balance of the aquatic ecosystem. The presence of antibiotics may reduce the water quality of the water body, affecting the survival of aquatic organisms and the safety of human drinking water. In addition, the selective inhibition of sensitive microorganisms by antibiotics may lead to a reduction in microbial diversity in the water body, thereby affecting the functions and services of the entire ecosystem.

[0003] In the prior art, penicillins are relatively stable in aqueous environments and are not easily degraded naturally, allowing them to persist in water for extended periods. Furthermore, penicillins are somewhat resistant to conventional chemical oxidants (such as chlorine and ozone), which limits their application in chemical oxidation methods for degrading these antibiotics. Furthermore, penicillins are somewhat resistant to photolysis by ultraviolet and visible light, which reduces the efficiency of photocatalytic degradation. Furthermore, penicillins may also adsorb onto suspended particles and sediments in water, making their removal difficult via traditional water treatment methods. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a method for promoting the degradation of penicillins in water.

[0005] A method for promoting the degradation of penicillin antibiotics in water comprises the following steps:

[0006] S1. Water quality testing;

[0007] Detection of penicillin antibiotics concentration and Ca in water 2+Parameters of concentration, DO and COD;

[0008] S2, medium adjustment;

[0009] Regulate Ca 2+ Concentration, when Ca in water 2+ The concentration is less than Ca 2+ When the set threshold value reaches the minimum value, calcium-containing substances are added to the water until Ca 2+ When the concentration reaches the set threshold; 2+ When the concentration is greater than the maximum value of the set threshold, ion exchange resin or lime softening method is used to remove excess Ca 2+ to Ca 2+ The concentration reaches the set threshold;

[0010] When the DO and COD in the water body are not exceeding the standard, add bio-metabolized organic matter to the water body until the concentration of bio-metabolized organic matter is 10-50 mg / L;

[0011] S3, catalytic degradation;

[0012] Add photocatalytic material to water at a concentration of 0.1-1 g / L and disperse it; then adjust the pH to 6.5-7.5, control the water temperature at 15-25°C, and stir at a speed of 40-80 rpm to carry out the hydrolysis reaction; at the same time, use ultraviolet light to irradiate the water body at an intensity of 10-20 mW / cm 2 , irradiation time is 2 to 4 hours;

[0013] S4, precipitation reaction;

[0014] Add 10-15% of the volume fraction of cells to the water body with a density of 1×10 6 cells / mL of Spirulina: then maintain the CO2 concentration in the water at 5-10 mM by adding NaHCO3 or introducing CO2 gas; then adjust the pH value to 8.5-9.0, start stirring and then add 10 mg / L polyacrylamide with a volume fraction of 5-7% as a flocculant, with a stirring speed of 100-150 rpm and a stirring time of 30-40 minutes. After settling for 1 hour, solid-liquid separation is performed, and the degradation is completed.

[0015] Description: The above method can make the sample in the water to be treated in good condition by adjusting the medium of the water to be treated using calcium ions and organic matter. Since calcium ions can coordinate with the carbonyl and carboxyl groups in the penicillin molecule, they can stabilize the hydrolysis reaction intermediates and accelerate the hydrolysis rate of penicillin antibiotics. In addition, the characteristic functional groups such as amino and thiol groups in the biological metabolic organic matter can also act as strong nucleophiles to promote the rapid hydrolysis of penicillin antibiotics. However, the direct use of calcium ions and biological metabolic organic media may cause the complexity of the water body and secondary pollution. Through the above threshold range and judgment method, it can be ensured that calcium ions and biological organic metabolic media do not cause secondary pollution to the water to be treated before degradation.

[0016] Furthermore, the set threshold is 50-100 mg / L.

[0017] Note: The above-mentioned threshold setting range has a good effect in promoting the degradation of antibiotics.

[0018] Furthermore, the standard that both DO and COD in the water body do not exceed the standard is the existing surface water environmental quality standard.

[0019] Note: Specifically, the existing surface water environmental quality standards refer to the indicators of the three types of water bodies in GB 3838-2002.

[0020] Furthermore, the calcium-containing substance is calcium ion-doped nanohydroxyapatite; the preparation method of the calcium ion-doped nanohydroxyapatite is:

[0021] S1-1. First, CaCl2 and SrCl2 were mixed and dissolved in deionized water according to a ratio of 8-10 mmol:1 mmol:100 mL to obtain a first mixed solution;

[0022] S1-2, adding a phosphoric acid solution having a mass concentration of 20-30% dropwise to the first mixed solution while stirring until the pH value reaches 7-9 to obtain a second mixed solution; the dropping speed is 0.5-1 mL / s; the stirring speed is 500-600 rpm;

[0023] S1-3. Under continuous stirring, slowly dropwise add ammonia water or sodium hydroxide to the second mixed solution to adjust the pH value to 10; then age the second mixed solution for 12 to 15 hours to obtain a suspension;

[0024] S1-4, centrifuging the suspension to obtain a supernatant and a precipitate, removing the supernatant, washing the precipitate with deionized water, and drying the washed precipitate to obtain a dried powder;

[0025] S1-5, calcining the dried powder at 400-500° C. for 2-3 hours to obtain calcium ion-doped nano-hydroxyapatite.

[0026] Description: The dissolution equilibrium of the above-mentioned calcium ion-doped nanohydroxyapatite in water will lead to the gradual release of calcium ions; under a certain pH value and ionic strength, the calcium ions on the surface of the nanohydroxyapatite can be exchanged with other ions in the water, thereby being released into the water body; and the microorganisms in the water body promote its dissolution and the release of calcium ions; the calcium ion-doped nanohydroxyapatite has good biocompatibility, has little effect on organisms in the water body and can continuously and stably release calcium ions, maintain the calcium ion concentration of the water body, which is beneficial to the long-term stability of water quality and avoids new pollution during water treatment. In addition to releasing calcium ions, nanohydroxyapatite can also adsorb and accumulate heavy metal ions and other pollutants in water through its porous structure and large specific surface area, thereby promoting the degradation process.

[0027] Furthermore, the aging treatment is: subjecting the second mixed liquid to a gradient temperature change within a range of 10° C. to 40° C.

[0028] Note: The above temperature gradient change can promote crystal growth to improve its crystallinity and stability.

[0029] Furthermore, the temperature of the second mixed liquid is gradually changed within 10°C to 40°C: after the temperature of the second mixed liquid is lowered to 10°C, it is heated to 40°C after 1 to 2 hours, and then maintained for 10 minutes, and then cooled to 10°C for 1 to 2 hours, and the heating and cooling cycles are repeated until the treatment is completed.

[0030] Furthermore, the preparation method of the biological metabolic organic matter is:

[0031] First, the corn stalks are cut into small segments of 2-5 cm; and softened by steaming or soaking in water to obtain softened stalks;

[0032] Then, the softened straw is mixed with a composite fermentation agent, wherein the inoculation amount of the composite fermentation agent is 1 to 5% of the weight of the straw; and molasses accounting for 5 to 10% of the weight of the straw is added;

[0033] The inoculated softened straw is then piled into compost, fermented at 30-40°C, the pH is adjusted to 6.0-7.5, and fermented for 4-6 weeks, with the pile turned over every week; after the fermentation is completed, biological metabolic organic matter is obtained.

[0034] Note: The characteristic functional groups such as amino and thiol in the bio-metabolism organic matter prepared by the above method can also act as strong nucleophilic reagents to promote the rapid hydrolysis of penicillin antibiotics. At the same time, the preparation of bio-metabolism organic matter using corn straw and composite microbial agents can realize resource recycling. Through biological metabolism, it is converted into organic matter, realizing the resource utilization of waste and reducing environmental pollution. It has a relatively low impact on the environment.

[0035] Furthermore, the composite fermentation agent includes two or more of Bacillus subtilis, Bacillus licheniformis, lactic acid bacteria and Candida.

[0036] Description: Composite fermentation bacteria can decompose organic matter in water, improve water quality, and inhibit the growth of harmful bacteria in water treatment. Fungi such as Candida can produce flocculants to help aggregate suspended particles in the water and cause them to precipitate, thereby clarifying the water. Microorganisms can change the redox state of water during metabolism, helping to remove heavy metal ions and other toxic substances in the water. By introducing composite fermentation bacteria, the balance of the water ecosystem can be promoted and aquatic biodiversity can be restored.

[0037] Furthermore, the fermentation humidity is 50-60%.

[0038] Note: Fermentation humidity within the above range helps create an environment conducive to microbial fermentation, thereby improving fermentation efficiency.

[0039] The beneficial effects of the present invention are:

[0040] The present invention uses calcium ions and organic matter to adjust the medium of the water body to be treated, so that the sample in the water body to be treated can be in a good state. Since calcium ions can coordinate with the carbonyl and carboxyl groups in the penicillin molecule, the hydrolysis reaction intermediates are stabilized and the hydrolysis rate of the penicillin antibiotic is accelerated. In addition, the characteristic functional groups such as amino and thiol groups in the biological metabolic organic matter can also act as strong nucleophilic reagents to promote the rapid hydrolysis of the penicillin antibiotic. At the same time, through the specific setting of the method, it is possible to avoid secondary pollution of the water body to be treated by calcium ions and biological organic metabolic media before degradation. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a flow chart of an embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to further illustrate the approach and effects achieved by the present invention, the technical solution of the present invention will be clearly and completely described below in conjunction with experiments.

[0043] Example 1: A method for promoting the degradation of penicillins in water, comprising the following steps:

[0044] S1. Water quality testing;

[0045] Detection of penicillin antibiotics concentration and Ca in water 2+ Parameters of concentration, DO and COD;

[0046] S2, medium adjustment;

[0047] Regulate Ca 2+ Concentration, when Ca in water 2+ The concentration is less than Ca 2+ When the set threshold value reaches the minimum value, calcium-containing substances are added to the water until Ca 2+ When the concentration reaches the set threshold; 2+ When the concentration is greater than the maximum value of the set threshold, ion exchange resin or lime softening method is used to remove excess Ca 2+ to Ca 2+ The concentration reaches the set threshold;

[0048] The concentration of the penicillin antibiotic is 4 mg / L, and the set threshold is 50-100 mg / L;

[0049] When both DO and COD in the water body are within the standard, bio-metabolized organic matter is added to the water body until the concentration of bio-metabolized organic matter is 10-50 mg / L; the standard for both DO and COD in the water body being within the standard is the existing surface water environmental quality standard (indicators for three types of water bodies in GB 3838-2002); when both DO and COD in the water body are within the standard, bio-metabolized organic matter is not added to the water body;

[0050] The calcium-containing substance is nano-hydroxyapatite doped with calcium ions; the preparation method of the calcium-ion-doped nano-hydroxyapatite is:

[0051] S1-1. First, CaCl2 and SrCl2 were mixed and dissolved in deionized water at a ratio of 9 mmol:1 mmol:100 mL to obtain a first mixed solution;

[0052] S1-2, adding a 25% mass concentration phosphoric acid solution dropwise to the first mixed solution while stirring until the pH value reaches 8, to obtain a second mixed solution; the dropping speed is 0.8 mL / s; the stirring speed is 550 rpm;

[0053] S1-3. Under continuous stirring, add aqueous ammonia dropwise to the second mixed solution to adjust the pH value to 10; then age the second mixed solution for 14 hours to obtain a suspension; the addition rate is 0.8 mL / s;

[0054] The aging treatment is to gradually change the temperature of the second mixed liquid within a range of 10° C. to 40° C.

[0055] The temperature of the second mixed liquid is gradually changed within 10°C to 40°C: after the temperature of the second mixed liquid is reduced to 10°C, it is heated to 40°C after 1.5 hours, and then maintained for 10 minutes, and then cooled to 10°C for 1.5 hours, and the heating and cooling are repeated until the treatment is completed.

[0056] S1-4, centrifuging the suspension to obtain a supernatant and a precipitate, removing the supernatant, washing the precipitate with deionized water, and drying the washed precipitate to obtain a dried powder;

[0057] S1-5, calcining the dried powder at 450° C. for 2.5 h to obtain calcium ion-doped nanohydroxyapatite;

[0058] The preparation method of the biological metabolic organic matter is:

[0059] First, the corn stalks were cut into 4 cm segments and softened by soaking in water for 12 h to obtain softened stalks.

[0060] Then, the softened straw is mixed with a composite fermentation agent, wherein the inoculation amount of the composite fermentation agent is 3% of the weight of the straw; and molasses accounting for 8% of the weight of the straw is added;

[0061] The inoculated softened straw is then piled into compost, fermented at 35°C, the pH is adjusted to 6.5, and fermented for 5 weeks, with the pile turned over every week; after the fermentation is completed, biological metabolic organic matter is obtained.

[0062] The composite fermentation agent is obtained by mixing Bacillus subtilis, Bacillus licheniformis, lactic acid bacteria and Candida in equal proportions; the fermentation humidity is 55%;

[0063] S3, catalytic degradation;

[0064] 0.5 g / L of photocatalytic material was dispersed in water; the pH was then adjusted to 7.0, the water temperature was controlled at 20°C, and the mixture was stirred at a speed of 60 rpm for hydrolysis reaction; at the same time, ultraviolet light was used to irradiate the water at an intensity of 15 mW / cm 2 , irradiation time is 3h;

[0065] S4, precipitation reaction;

[0066] Add 12% of the volume fraction of cells with a density of 1×10 6cells / mL of Spirulina: then by adding NaHCO3, the CO2 concentration in the water body is maintained at 6mM; then the pH value is adjusted to 8.8, stirring is started, and then 6% 10mg / L polyacrylamide is added as a flocculant, the stirring speed is 120rpm, the stirring time is 35min, and after precipitation for 1h, solid-liquid separation is performed, that is, degradation is completed, and degraded water is obtained.

[0067] Example 2: This example differs from Example 1 in that the concentration of the penicillin antibiotic is 5 mg / L.

[0068] Example 3: This example differs from Example 1 in that the concentration of the penicillin antibiotic is 2 mg / L.

[0069] Example 4: This example differs from Example 1 in that bio-metabolized organic matter is added to the water body until the bio-metabolized organic matter concentration reaches 10 mg / L.

[0070] Example 5: This example differs from Example 1 in that bio-metabolized organic matter is added to the water body until the concentration of bio-metabolized organic matter is 50 mg / L.

[0071] Example 6: This example differs from Example 1 in that, in the S3 catalytic degradation, 1 g / L of photocatalytic material is dispersed in the water body; then the pH is adjusted to 6.5, the water temperature is controlled at 15°C, and stirring is performed at a stirring speed of 80 rpm to carry out the hydrolysis reaction.

[0072] Example 7: This example differs from Example 1 in that, in the S3 catalytic degradation, 0.1 g / L of photocatalytic material is dispersed in the water body; then the pH is adjusted to 7.5, the water temperature is controlled at 25°C, and stirring is performed at a stirring speed of 40 rpm to carry out the hydrolysis reaction.

[0073] Example 8: This example differs from Example 1 in that, during the catalytic degradation of S3, an ultraviolet lamp is used to irradiate the water body, and the illumination intensity is 10 mW / cm 2 , the irradiation time is 4h.

[0074] Example 9: This example differs from Example 1 in that, during the catalytic degradation of S3, an ultraviolet lamp is used to irradiate the water body, and the illumination intensity is 20 mW / cm 2 , the irradiation time is 2h.

[0075] Example 10: This example differs from Example 1 in that, in the S4 precipitation reaction, 10% of the volume fraction of cells with a density of 1×10 6cells / mL of Spirulina: CO2 concentration in the water was maintained at 10 mM by introducing CO2 gas; and the pH value was adjusted to 8.5.

[0076] Example 11: This example differs from Example 1 in that, in the S4 precipitation reaction, 15% of the volume fraction of cells with a density of 1×10 6 cells / mL of Spirulina: CO2 concentration in the water was maintained at 5 mM by introducing CO2 gas; and the pH value was adjusted to 9.0.

[0077] Example 12: This example is different from Example 1 in that, in the S4 precipitation reaction, stirring is started and then polyacrylamide with a volume fraction of 5% 10 mg / L is added as a flocculant, the stirring speed is 100 rpm, and the stirring time is 30 min.

[0078] Example 13: This example is different from Example 1 in that, in the S4 precipitation reaction, stirring is started and then polyacrylamide with a volume fraction of 7% (10 mg / L) is added as a flocculant, the stirring speed is 150 rpm, and the stirring time is 40 min.

[0079] Example 14: This example differs from Example 1 in that the preparation parameters of the calcium ion-doped nanohydroxyapatite are different. S1-1. First, CaCl2 and SrCl2 are mixed and dissolved in deionized water according to 8 mmol:1 mmol:100 mL to obtain a first mixed solution.

[0080] S1-2, adding a 20% phosphoric acid solution to the first mixed solution while stirring until the pH value reaches 7-9 to obtain a second mixed solution; the addition rate is 0.5 mL / s; the stirring speed is 500 rpm;

[0081] S1-3. Under continuous stirring, slowly dropwise add ammonia water or sodium hydroxide to the second mixed solution to adjust the pH value to 10; then age the second mixed solution for 12 hours to obtain a suspension;

[0082] The aging treatment is to subject the second mixed solution to a gradient change within a temperature range of 10° C. to 40° C.

[0083] The second mixed liquid is subjected to a gradient change within 10°C to 40°C: after the temperature of the second mixed liquid is lowered to 10°C, it is heated to 40°C after 1 hour, then maintained for 10 minutes, and then cooled to 10°C for 2 hours, and the heating and cooling are repeated until the treatment is completed.

[0084] S1-4, centrifuging the suspension to obtain a supernatant and a precipitate, removing the supernatant, washing the precipitate with deionized water, and drying the washed precipitate to obtain a dried powder;

[0085] S1-5, calcining the dried powder at 400° C. for 2 h to obtain calcium ion-doped nano-hydroxyapatite.

[0086] Example 15: This example differs from Example 1 in that the preparation parameters of the calcium ion-doped nanohydroxyapatite are different. S1-1. First, CaCl2 and SrCl2 are mixed and dissolved in deionized water at a ratio of 10 mmol:1 mmol:100 mL to obtain a first mixed solution.

[0087] S1-2, adding a phosphoric acid solution having a mass concentration of 20-30% dropwise to the first mixed solution while stirring until the pH value reaches 7-9 to obtain a second mixed solution; the dropping speed is 1 mL / s; the stirring speed is 600 rpm;

[0088] S1-3. Under continuous stirring, slowly add aqueous ammonia or sodium hydroxide dropwise to the second mixed solution to adjust the pH value to 10; then age the second mixed solution for 15 hours to obtain a suspension;

[0089] The aging treatment is to subject the second mixed solution to a gradient change within a temperature range of 10° C. to 40° C.

[0090] The second mixed solution is subjected to a gradient change within the range of 10°C to 40°C: the temperature of the second mixed solution is lowered to 10°C, then raised to 40°C after 2 hours, then maintained for 10 minutes, and then lowered to 10°C for 1 hour, and the temperature is repeatedly raised and lowered until the treatment is completed;

[0091] S1-4, centrifuging the suspension to obtain a supernatant and a precipitate, removing the supernatant, washing the precipitate with deionized water, and drying the washed precipitate to obtain a dried powder;

[0092] S1-5, calcining the dried powder at 500° C. for 3 h to obtain calcium ion-doped nano-hydroxyapatite.

[0093] Example 16: This example differs from Example 1 in that the preparation parameters of the bio-metabolism organic matter are different. First, the corn stalks are cut into small segments of 2 cm; they are softened by steam or water soaking to obtain softened straw; then the softened straw is mixed with a composite fermentation agent, and the inoculation amount is 1% of the straw weight; molasses accounting for 5% of the straw weight is added; the inoculated softened straw is then piled into compost, fermented at 30°C, the pH is adjusted to 6.0, and fermented for 4 weeks, with the pile turned over every week; after the fermentation is completed, bio-metabolism organic matter is obtained; the fermentation humidity is 50%.

[0094] Example 17: This example differs from Example 1 in that the preparation parameters of the bio-metabolism organic matter are different. First, the corn stalks are cut into small segments of 5 cm; they are softened by steam or water soaking to obtain softened straw; the softened straw is then mixed with a composite fermentation agent, with an inoculation amount of 5% of the straw weight; molasses accounting for 10% of the straw weight is added; the inoculated softened straw is then piled into compost, fermented at 40°C, the pH is adjusted to 7.5, and fermented for 6 weeks, with the pile turned over every week; after the fermentation is completed, bio-metabolism organic matter is obtained; the fermentation humidity is 60%.

[0095] Example 18: This example is different from Example 1 in that the composite fermentation agent is obtained by mixing Bacillus subtilis and Bacillus licheniformis in equal proportions.

[0096] Example 19: This example is different from Example 1 in that, in the preparation method of the biological metabolic organic matter described in S1-5, steam is used for softening, and the steaming time is 4 hours to obtain softened straw.

[0097] Experimental Example: The description of this experimental example is based on the scheme described in Example 1, and is intended to illustrate the practical application effect of the present invention.

[0098] Experimental Example: 1. The methods of Examples 1 to 17 were used to degrade penicillin G in water. The degradation test results are as follows:

[0099] 1. To explore the effects of different treatment methods on the degradation performance of penicillin G;

[0100] Comparative Example 1: The difference from Example 1 is that the treatment of step S2 is not performed, and the operations of step S3 and step S4 are directly performed on the water body.

[0101] Comparative Example 2: The difference from Example 1 is that the threshold is set equal to the concentration of penicillin antibiotics;

[0102] Comparative Example 3: The difference from Example 1 is that the calcium-containing substance is calcium chloride;

[0103] Comparative Example 4: The difference from Example 1 is that no aging treatment is performed;

[0104] Comparative Example 5: The difference from Example 1 is that the treatment of S1-5 is not performed.

[0105] Example 1 and Comparative Examples 1 to 5 were compared, as shown in Table 1.

[0106] Table 1 Penicillin G degradation experimental results under different treatment methods

[0107]

[0108]

[0109] As can be seen from Table 1, by comparing Example 1 with Comparative Example 1, it can be seen that Example 1 has a better degradation effect. In contrast, Comparative Example 1 does not utilize calcium ions and biological metabolic organic matter to adjust the water environment to promote the degradation process of penicillin antibiotics. Since calcium ions can coordinate with the carbonyl and carboxyl groups in the penicillin molecule, accelerating the hydrolysis rate of penicillin antibiotics, and characteristic functional groups such as amino and thiol groups in the biological metabolic organic matter can also act as strong nucleophiles to promote the rapid hydrolysis of penicillin antibiotics, Example 1 has this design and therefore has a good degradation effect.

[0110] By comparing Example 1 with Comparative Example 2, it can be seen that compared with setting the calcium ion threshold to the same concentration of penicillin antibiotics in Comparative Example 2, the corresponding ratio of calcium ions to penicillin antibiotic concentrations in Example 1 is more suitable for the degradation process of antibiotics. This may be because, although calcium ions have a promoting effect on the degradation of antibiotics, when the antibiotic concentration is too high or the calcium ion concentration is too low, calcium ions cannot provide a good environment that promotes antibiotic hydrolysis.

[0111] By comparing Example 1 with Comparative Example 3, it can be seen that the calcium ion used in Comparative Example 3 is calcium chloride. Compared with calcium chloride, the dissolution equilibrium of the calcium ion-doped nanohydroxyapatite in water will lead to the gradual release of calcium ions, and the calcium ions on the surface of the nanohydroxyapatite can be exchanged with other ions in the water, thereby being released into the water body; and the calcium ion-doped nanohydroxyapatite has good biocompatibility, has little effect on organisms in the water body, and can continuously and stably release calcium ions, maintain the calcium ion concentration of the water body, and promote the degradation process.

[0112] By comparing Example 1 with Comparative Example 4, it can be seen that in Comparative Example 4, without aging treatment, the degradation efficiency of penicillin antibiotics is reduced. This may be because the aging treatment and temperature gradient setting in Example 1 can enable the crystals in the system to grow rapidly and form a specific state to facilitate the subsequent degradation process.

[0113] By comparing Example 1 with Comparative Example 5, it can be found that no heat treatment is performed in Comparative Example 5, and a more optimized surface structure cannot be generated, so that the surface of the calcium ion-doped nanohydroxyapatite cannot better aggregate heavy metal ions, and without heat treatment, its own crystallinity and stability cannot be improved, thereby affecting the use process.

[0114] 2. Investigate the effects of different parameters on the degradation performance of penicillin G;

[0115] Examples 1 to 17 were compared, as shown in Table 1.

[0116] Table 2 Penicillin G degradation test results under different parameters

[0117] parameter Degradation rate% Example 1 99 Example 2 97 Example 3 98 Example 4 96 Example 5 97 Example 6 95 Example 7 96 Example 8 96 Example 9 95 Example 10 97 Example 11 96 Example 12 95 Example 13 96 Example 14 96 Example 15 97 Example 16 97 Example 17 95

[0118] Comparing Example 1, Example 2 and Example 3, it can be found that the ratio of the concentration of penicillin antibiotics to the calcium ion setting threshold in Example 1 is more preferred; comparing Example 1, Example 4 and Example 5, it can be found that the concentration of biological metabolic organic matter added to the water body in Example 1 is more preferred, which may be because adding too much will cause linear pollution of the water body, and too little will not achieve a good effect; comparing Example 1, Example 6 and Example 7, it can be found that the hydrolysis conditions in the S3 catalytic degradation in Example 1 are better, indicating that different hydrolysis parameters have a certain impact on the degradation of penicillin in the water body, among which the hydrolysis conditions of Example 1 are preferred; comparing Example 1, Example 8 ... concentration of biological metabolic organic matter added to the water body in Example 1 is more preferred, In Example 9, it can be found that the illumination conditions of Example 1 are more preferred. This may be because light catalyzes the degradation of penicillin in the water, thereby accelerating the degradation process. The photocatalytic parameters have an impact on the degradation of penicillin G, and the photocatalytic parameters are preferably those of Example 1. By comparing Example 1, Example 10, and Example 11, it can be found that the precipitation treatment parameters in Example 1 are optimal. Spirulina combined with carbon dioxide can utilize the adsorption capacity of the spirulina cell surface to adsorb suspended matter and colloidal substances in the water, which helps to remove suspended matter and sediment in the water. Through the adsorption and precipitation effects of spirulina, the concentration of suspended matter and turbidity in the water can be reduced, and the transparency of the water can be improved. In addition, during the growth process, spirulina can absorb and utilize nutrients such as nitrogen and phosphorus in the water body, which helps to reduce the risk of eutrophication of the water body; in the system of spirulina combined with carbon dioxide, the introduction of carbon dioxide not only promotes the growth and degradation ability of spirulina, but also may affect the formation of sediment by changing the water environment. This synergistic effect helps to more efficiently remove sediment from the water body; by comparing Example 1, Example 12 and Example 13, it can be found that the precipitation stirring parameters of Example 1 are more preferred; by comparing Example 1, Example 14 and Example 15, it can be found that the preparation parameters of the calcium ion-doped nanohydroxyapatite in Example 1 are more preferred; by comparing Example 1, Example 16 and Example 17, it can be found that the preparation parameters of the biological metabolic organic matter in Example 1 are more preferred.

Claims

1. A method for promoting the degradation of penicillin antibiotics in water, characterized in that: The following steps are involved: S1. Water quality testing; Detection of penicillin antibiotics concentration and Ca in water 2+ Parameters of concentration, DO and COD; S2, medium adjustment; Regulate Ca 2+ Concentration, when Ca in water 2+ The concentration is less than Ca 2+ When the set threshold value reaches the minimum value, calcium-containing substances are added to the water until Ca 2+ When the concentration reaches the set threshold; 2+ When the concentration is greater than the maximum value of the set threshold, ion exchange resin or lime softening method is used to remove excess Ca 2+ to Ca 2+ The concentration reaches the set threshold; When the DO and COD in the water body are not exceeding the standard, add bio-metabolized organic matter to the water body until the concentration of bio-metabolized organic matter is 10-50 mg / L; The preparation method of the biological metabolic organic matter is: First, the corn stalks are cut into small segments of 2-5 cm; and softened by steaming or soaking in water to obtain softened stalks; Then, the softened straw is mixed with a composite fermentation agent, wherein the inoculation amount of the composite fermentation agent is 1 to 5% of the weight of the straw; and molasses accounting for 5 to 10% of the weight of the straw is added; The inoculated softened straw is then piled into compost, fermented at 30-40°C, the pH is adjusted to 6.0-7.5, and fermented for 4-6 weeks, with the pile turned weekly. After fermentation is complete, biological metabolic organic matter is obtained. S3, catalytic degradation; Add photocatalytic material to water at a concentration of 0.1-1 g / L and disperse it; then adjust the pH to 6.5-7.5, control the water temperature at 15-25°C, and stir at a speed of 40-80 rpm to carry out the hydrolysis reaction; at the same time, use ultraviolet light to irradiate the water body at an intensity of 10-20 mW / cm 2 , irradiation time is 2 to 4 hours; S4, precipitation reaction; Add 10-15% of the volume fraction of cells to the water body with a density of 1×10 6 cells / mL of Spirulina: then maintain the CO2 concentration in the water at 5-10 mM by adding NaHCO3 or introducing CO2 gas; then adjust the pH value to 8.5-9.0, start stirring and then add 10 mg / L polyacrylamide with a volume fraction of 5-7% as a flocculant, with a stirring speed of 100-150 rpm and a stirring time of 30-40 minutes. After settling for 1 hour, solid-liquid separation is performed, and the degradation is completed.

2. The method for promoting the degradation of penicillin antibiotics in water according to claim 1, characterized in that: The set threshold is 50-100 mg / L.

3. The method for promoting the degradation of penicillin antibiotics in water according to claim 1, wherein: The standard that both DO and COD in the water body do not exceed the standard is the existing surface water environmental quality standard.

4. The method for promoting the degradation of penicillin antibiotics in water according to claim 1, wherein: The calcium-containing substance is calcium ion-doped nanohydroxyapatite; the preparation method of the calcium ion-doped nanohydroxyapatite is: S1-1. First, CaCl2 and SrCl2 were mixed and dissolved in deionized water according to a ratio of 8-10 mmol:1 mmol:100 mL to obtain a first mixed solution; S1-2, adding a phosphoric acid solution having a mass concentration of 20-30% dropwise to the first mixed solution while stirring until the pH value reaches 7-9, to obtain a second mixed solution; wherein the dropping speed is 0.5-1 mL / s; and the stirring speed is 500-600 rpm; S1-3. Under continuous stirring, adding aqueous ammonia or sodium hydroxide dropwise to the second mixed solution to adjust the pH value to 10; then aging the second mixed solution for 12 to 15 hours to obtain a suspension; S1-4, centrifuging the suspension to obtain a supernatant and a precipitate, removing the supernatant, washing the precipitate with deionized water, and drying the washed precipitate to obtain a dried powder; S1-5, calcining the dried powder at 400-500° C. for 2-3 hours to obtain calcium ion-doped nano-hydroxyapatite.

5. The method for promoting the degradation of penicillin antibiotics in water according to claim 4, characterized in that: The aging treatment is to gradually change the temperature of the second mixed liquid within a range of 10° C. to 40° C.

6. The method for promoting the degradation of penicillin antibiotics in water according to claim 5, characterized in that: The temperature of the second mixed liquid is gradually changed within 10°C to 40°C: after the temperature of the second mixed liquid is reduced to 10°C, it is heated to 40°C after 1 to 2 hours, and then maintained for 10 minutes, and then cooled to 10°C for 1 to 2 hours, and the heating and cooling are repeated until the treatment is completed.

7. The method for promoting the degradation of penicillin antibiotics in water according to claim 1, characterized in that: The composite fermentation bacteria agent comprises two or more of Bacillus subtilis, Bacillus licheniformis, lactic acid bacteria and Candida.

8. The method for promoting the degradation of penicillin antibiotics in water according to claim 1, characterized in that: The fermentation humidity is 50-60%.

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