CN111804336B

CN111804336B - A kind of organic composite photocatalyst for degrading antibiotics and preparation method thereof

Info

Publication number: CN111804336B
Application number: CN202010742033.9A
Authority: CN
Inventors: 饶义剑; 张艳; 袁振波; 陆柳伸; 刘昌梅; 杨丽烽
Original assignee: Jiangnan University
Current assignee: Jiangnan University
Priority date: 2020-07-29
Filing date: 2020-07-29
Publication date: 2021-05-04
Anticipated expiration: 2040-07-29
Also published as: CN111804336A

Abstract

The invention discloses an organic composite photocatalyst for degrading antibiotics and a preparation method thereof, belonging to the technical field of treatment of pollutants in water. The method of the invention obtains Hexaacetylcercosporin (HARCP) by reducing and acetylating modified Cercosporin (CP), and obtains the supported photocatalyst HARCP/HAp by loading HARCP on hydroxyapatite (HAp) through a simple green method. The HARCP/HAp can generate superoxide radical, hydroxyl radical and cavity under the irradiation of 32W white light lamp and even sunlight, and react with antibiotic, thereby achieving the purpose of degrading antibiotic. By reasonable optimization of reaction conditions, the tetracycline can be degraded with a degradation rate as high as 98.89% within 30min of reaction under illumination by adopting the method.

Description

Organic composite photocatalyst for degrading antibiotics and preparation method thereof

Technical Field

The invention relates to an organic composite photocatalyst for degrading antibiotics and a preparation method thereof, belonging to the technical field of treatment of pollutants in water.

Background

About 73% of all antibiotics sold in the world are used for edible animals, and the heavy use of antibiotics can cause a large amount of waste antibiotics to directly enter the water environment, and the long-term exposure to the environment with antibiotics can cause the imbalance of the intestinal flora of organisms and even cause the abnormality of the intestinal flora of human bodies.

In recent years, many techniques have been developed for degradation of antibiotics, such as adsorption, chemical, biodegradation, electrochemical methods, etc., which, however, make it difficult to completely remove antibiotics. Photocatalytic action has been attracting attention as a method recently developed because of its advantages such as high efficiency and sustainability. Although the degradation of antibiotics can be carried out by means of photocatalysts, in particular semiconductor photocatalysts such as silver phosphate, tungsten trioxide/bismuth vanadate and the like, their use is limited due to their high price and heavy metal contamination. Therefore, it is desirable and important to develop a low-cost, environmentally friendly photocatalytic degradation method using a low-energy light source under mild conditions.

Organic compounds are an ideal choice for degrading tetracycline as photocatalysts, but few examples are currently applied for degrading antibiotics. Cercosporin (CP), a naturally occurring perylenequinone compound, has a catalytic effect when applied to the field of photocatalytic organic synthesis, but has a general catalytic ability.

Disclosure of Invention

[ technical problem ]:

the traditional adsorption method, chemical method, biological degradation method, electrochemical method and the like are difficult to completely remove antibiotics. The photocatalytic degradation of antibiotics by the photocatalyst has the advantages of high efficiency, sustainability and the like, wherein the organic compound is an ideal choice for degrading tetracycline by the photocatalyst, but the examples of the antibiotics degradation are few at present, and further exploration is needed. Cercosporin (CP), a naturally occurring perylenequinone compound, has a catalytic effect when applied to the field of photocatalytic organic synthesis, but has a general catalytic ability.

[ technical solution ]:

aiming at the problems, the invention provides an organic composite photocatalyst for degrading antibiotics, Cercosporin (CP) is subjected to reduction acetylation modification to obtain Hexaacetylcercosporin (HARCP), and the HARCP is loaded on hydroxyapatite (HAp) to obtain a loaded photocatalyst HARCP/HAp. The prepared catalyst HARCP/HAp can improve the electron transfer efficiency and the separation efficiency of electron-hole pairs, thereby improving the degradation efficiency of antibiotics. The invention takes the HARCP as the photocatalyst for the first time, and successfully loads the HARCP on the HAp, thereby realizing the complete degradation of different antibiotics under the irradiation of visible light.

The invention provides a method for preparing an organic composite photocatalyst, which comprises the following steps: cercosporin (CP) is taken as a raw material, reduction acetylation modification is carried out on the Cercosporin (CP) to obtain hexaacetyl cercosporin (HARCP), and the HARCP is loaded on hydroxyapatite (HAp) to obtain a loaded photocatalyst HARCP/HAp.

In one embodiment of the present invention, the Cercosporin (CP) is subjected to reductive acetylation modification to obtain Hexaacetylcercosporin (HARCP): adding cercospora micrantha, acetic anhydride, magnesium powder and N, N-dimethyl-4-aminopyridine into a reaction vessel, and stirring for reaction for 1-3 hours; adding acetic anhydride again after the reaction is finished, and continuously stirring and reacting for 1-3 hours; and adding an extracting agent for extraction after the reaction is finished, then filtering, concentrating the filtrate, and separating to obtain the hexaacetyl reducing cercosporin.

In one embodiment of the present invention, the molar ratio of cercosporin to magnesium powder is 1: (4-100).

In one embodiment of the invention, the molar ratio of cercosporin to N, N-dimethyl-4-aminopyridine is 1: (1-20).

In one embodiment of the invention, the molar ratio of cercosporin to acetic anhydride is 1: (10-1000).

In one embodiment of the invention, the HARCP is loaded onto hydroxyapatite (HAp) by a solvent method.

In one embodiment of the present invention, the method for loading the HARCP on the hydroxyapatite (HAp) comprises:

weighing HARCP, dissolving in an organic solvent, adding HAp after the HARCP is completely dissolved, stirring for reaction, performing suction filtration to obtain a solid, and washing and drying the obtained solid to obtain the supported photocatalyst HARCP/HAp.

In one embodiment of the present invention, the organic solvent is any one of methanol, ethanol, dichloromethane, ethyl acetate, or acetonitrile.

In one embodiment of the present invention, the mass ratio of HARCP to HAp is 1: (10-1000).

In one embodiment of the invention, the stirring reaction time is 5 to 48 hours.

In one embodiment of the invention, the washing method comprises washing with methanol and water for 2-5 times respectively.

In one embodiment of the present invention, the drying conditions are: vacuum drying at 20-50 deg.C overnight.

The invention provides a supported photocatalyst HARCP/HAp prepared by the preparation method.

The invention provides an application of the supported photocatalyst HARCP/HAp in degrading antibiotics.

In one embodiment of the invention, the antibiotic is tetracycline, penicillin of beta-lactam, amoxicillin, ampicillin, cephalexin, cefixime, or the like; sulfadiazine, sulfamethoxazole, trimethoprim, etc. of the sulfonamides; norfloxacin, ofloxacin, ciprofloxacin, sparfloxacin and the like of quinolones; macrolides such as erythromycin and azithromycin.

In one embodiment of the invention, the method for degrading antibiotics by the supported photocatalyst HARCP/HAp is as follows:

the supported photocatalyst HARCP/HAp is put into the sewage containing antibiotics, and continuous degradation reaction is carried out under the irradiation of visible light.

In one embodiment of the present invention, the visible light is natural sunlight or a 5-32W white light lamp is used as a light source.

In one embodiment of the invention, the pH value of the antibiotic-containing sewage is 3-9.

In one embodiment of the invention, the amount of the HARCP/HAp added is 0.5-5g/L of the antibiotic-containing wastewater, and the concentration of the antibiotic-containing wastewater is 5-70 mg/L.

In one embodiment of the present invention, the time of the degradation reaction is 5 to 30 min.

[ advantageous effects ]:

(1) the photocatalyst HARCP/HAp prepared by the invention can improve the electron transfer efficiency and the separation efficiency of electron-hole pairs, thereby improving the degradation efficiency of antibiotics. Specifically, the photocatalyst HARCP/HAp prepared by the invention can degrade various different antibiotics, has high degradation efficiency, and has degradation rate of about 80% for various different antibiotics, especially the degradation rate can almost reach 100% when tetracycline is degraded.

(2) The photocatalyst prepared by the invention has easy separation of HARCP/HAp, can be recycled, and still retains high activity after being recycled for 3 times.

(3) The supported photocatalyst HARCP/HAp is synthesized by a green simple solvent method, and the preparation method is simple.

(4) The method is environment-friendly: when the catalyst is used for degrading antibiotics, only the supported photocatalyst HARCP/HAp is added in the reaction process, the reaction is carried out under illumination, and the HARCP/HAp is stable in the reaction process and cannot cause secondary pollution to the environment.

(5) High-efficiency and time-saving: when the catalyst is used for degrading antibiotics, only the HARCP/HAp is needed to be put into an antibiotic solution, the mixture is stirred for 5-30min under a dark condition, and then the mixture is irradiated for 10min under a 32W white light lamp or sunlight, so that various different antibiotics can be effectively degraded.

Drawings

FIG. 1 is an infrared spectrum of HAp, HARCP and HARCP/HAp in example 1.

FIG. 2 is an inverted fluorescence microscope image of HARCP/HAp under dark field in example 1.

FIG. 3 is a graph of the degradation profile of tetracycline solutions at different concentrations.

FIG. 4 is a graph of the degradation profile of tetracycline solutions at various pH values.

FIG. 5 is a graph of the degradation profile of 500mL tetracycline solution in example 10 in sunlight.

FIG. 6 is a graph of the degradation profile of the 1L tetracycline solution of example 11 in sunlight.

FIG. 7 is a graph showing the degradation of tetracycline by HARCP/HAp catalyst in example 14.

FIG. 8 is a graph of tetracycline degradation by different catalysts.

FIG. 9 is a graph showing the degradation of tetracycline by the photocatalyst CP/HAp in comparative example 4.

Detailed Description

The invention is further illustrated by the following examples.

Example 1 preparation of Supported photocatalyst HARCP/HAp

(1) Preparation of HARCP

Cercosporin (20mg), acetic anhydride (400. mu.L), magnesium powder (30mg), N-dimethyl-4-aminopyridine (50mg) and a stirrer were added to a reaction vessel and reacted for 2 hours under nitrogen protection. After the reaction was completed, acetic anhydride (400. mu.L) was added again, and the reaction was continued for 2 hours. After completion of the reaction, 20mL of methylene chloride was added to the reaction solution, followed by filtration, and the obtained filtrate was washed three times with 10mL of distilled water. And finally, adding anhydrous magnesium sulfate into the organic phase, drying, performing suction filtration to obtain filtrate, and concentrating by using a rotary evaporator. The hexaacetyl reducing cercosporin (HARCP) is separated by 200-300 mesh silica gel column chromatography with methanol/dichloromethane (v: v ═ 1:100) as eluent.

(2) Preparation of Supported photocatalyst HARCP/HAp

Weighing 10mg of prepared HARCP, dissolving in 50mL of methanol, adding 1g of hydroxyapatite HAp after complete dissolution, magnetically stirring for 24h, performing suction filtration to obtain a solid, respectively washing the obtained solid with methanol and water for 3 times, and then performing vacuum drying at 30 ℃ overnight to obtain the photocatalyst HARCP/HAp.

In this example, the raw material hydroxyapatite HAp, the intermediate product hexaacetyl cercosporin HARCP, and the prepared photocatalyst HARCP/HAp were subjected to infrared tests, FIG. 1 is an infrared spectrum of HAp, HARCP, and HARCP/HAp in this example, and it can be seen from FIG. 1 that the synthesized infrared spectrum of HARCP/HAp contains characteristic peaks of HARCP and HAp at the same time, indicating that the HARCP/HAp photocatalyst was successfully synthesized by the method of the present invention.

The HARCP/HAp prepared in this example was observed under an inverted fluorescence microscope, and FIG. 2 is an inverted fluorescence microscope image of the HARCP/HAp in this example under a dark field. It can be seen that the synthesized HARCP/HAp catalyst of this example can observe green fluorescence (FIG. 2 is black and white, which is a white portion of FIG. 2) under an inverted fluorescence microscope, wherein HARCP has green fluorescence, and HAp does not have fluorescence.

[ example 2 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 50mg/L tetracycline solution at room temperature, pH was adjusted to 9 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The sample was tested by HPLC, the mobile phase was acetonitrile: water (containing EDTA-Na)₂10 mM: ammonium acetate, 10mM ═ 1:9 ═ 17:83, flow rate 1mL/min, detection wavelength 280nm, and column temperature 25 ℃.

The detection result shows that the tetracycline is basically and completely removed, and the degradation rate reaches 98.89%.

[ example 3 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 30mg/L tetracycline solution at room temperature, pH was adjusted to 9 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 74.02%.

[ example 4 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 40mg/L tetracycline solution at room temperature, pH was adjusted to 9 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 89.77%.

[ example 5 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 60mg/L tetracycline solution at room temperature, pH was adjusted to 9 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 94.21 percent.

[ example 6 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 70mg/L tetracycline solution at room temperature, pH was adjusted to 9 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 87.4 percent.

FIG. 3 is a graph of the degradation profile of tetracycline solutions at different concentrations. As can be seen from FIG. 3, the degradation effect is the best when the tetracycline solution is 50mg/L under otherwise identical conditions.

[ example 7 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 50mg/L tetracycline solution at room temperature, pH was adjusted to 3 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 53.16%.

[ example 8 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 50mg/L tetracycline solution at room temperature, pH was adjusted to 5 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 86.69%.

[ example 9 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 50mg/L tetracycline solution at room temperature, pH was adjusted to 7 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The result shows that the degradation rate of the tetracycline reaches 94.34 percent.

FIG. 4 is a graph of the degradation profile of tetracycline solutions at various pH values. As can be seen from FIG. 4, the degradation effect is the best when the pH of the tetracycline solution is 9 under otherwise identical conditions.

[ example 10 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 1g of the catalyst HARCP/HAp prepared in example 1 was added to 500mL of 50mg/L tetracycline solution at room temperature, the pH was adjusted to 9 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under solar light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 100 percent. FIG. 5 is a graph showing the degradation profile of 500mL tetracycline solution in this example in sunlight.

[ example 11 ] degradation of Tetracycline

The photocatalytic test was carried out under 32W white light, 2g of the catalyst HARCP/HAp prepared in example 1 was added to 1L of a 50mg/L tetracycline solution at room temperature, the pH was adjusted to 9 with NaOH or HCl, the reaction system was stirred in the dark for 30min, and then reacted under solar light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 100 percent. FIG. 6 is a graph showing the degradation profile of 1L tetracycline solution in this example in sunlight.

Example 12 preparation of Supported photocatalyst HARCP/HAp

The procedure for preparing cercosporin reducing cercp is the same as in example 1.

Respectively weighing 5mg, 10mg and 15mg of prepared HARCP, dissolving in 50mL of methanol, adding 1g of hydroxyapatite HAp after complete dissolution, magnetically stirring for 24h, performing suction filtration to obtain a solid, respectively washing the obtained solid with methanol and water for 3 times, and then performing vacuum drying at 30 ℃ overnight to obtain three HARCP-loaded photocatalysts HARCP/HAp.

[ example 13 ] degradation of Tetracycline

The photocatalytic test was performed under 32W white light, 100mg of each of the three photocatalysts HARCP/HAp prepared in example 12 was added to 50mL of 50mg/L tetracycline solution at room temperature, pH was adjusted to 9 with NaOH or HCl, and the reaction system was stirred in the dark for 30min and then reacted under 32W white light for 10 min. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection results show that the degradation rates of the supported photocatalyst prepared by adding 5mg, 10mg and 15mg of HARCP to tetracycline are 85.31%, 99.52% and 89.16% respectively.

[ example 14 ] repeated experiments for degrading tetracycline

100mg of the catalyst HARCP/HAp prepared in example 1 was added to 50mL of 50mg/L tetracycline solution, the pH was adjusted to 9 with NaOH or HCl, and the reaction system was stirred in the dark for 30min and then was reacted under 32W white light for 10 min. And after the reaction is finished, carrying out suction filtration on a reaction system to obtain a solid, washing the solid for 3 times by using water and methanol, and then carrying out vacuum drying at 30 ℃ overnight to obtain a recovered photocatalyst to carry out a second reaction. And repeating the above operation for the third reaction. As shown in fig. 7, the degradation rates of the three repeated uses are: 99.00%, 97.51%, 96.98%. It was shown that the HARCP/HAp still retained high activity after 3 cycles of repeated use.

Comparative example 1 without catalyst HARCP/HAp

The photocatalytic test is carried out under 32W white light, the pH value of 50mL of 50mg/L tetracycline solution is adjusted to 9 at room temperature, no catalyst HARCP/HAp is added, the reaction system is firstly stirred for 30min under the dark condition, and then the reaction system is reacted for 10min under the illumination of a 32W white light lamp. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2. As shown in fig. 8.

The detection result shows that the tetracycline is not degraded basically.

Comparative example 2 addition of HAp

The photocatalytic test is carried out under 32W white light, the pH value of 50mL of 50mg/L tetracycline solution is adjusted to 9 at room temperature, 100mg of HAp is added, the reaction system is firstly stirred for 30min under the dark condition, and then the reaction system is reacted for 10min under the illumination of a 32W white light lamp. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2. As shown in fig. 8.

The detection result shows that the degradation rate of the tetracycline reaches 53.52%.

Comparative example 3 addition of HARCP

The photocatalytic test is carried out under 32W white light, the pH value of 50mL of 50mg/L tetracycline solution is adjusted to 9 at room temperature, 100mg of HARCP is added, the reaction system is firstly stirred for 30min under the dark condition, and then the reaction system is reacted for 10min under the illumination of a 32W white light lamp. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2. As shown in fig. 8.

The detection result shows that the degradation rate of the tetracycline reaches 9.34 percent.

Comparative example 4 addition of CP/HAp

Weighing 10mg of CP, dissolving in 50mL of methanol, adding 1g of hydroxyapatite (HAp) after complete dissolution, carrying out magnetic stirring for 24h, carrying out suction filtration to obtain a solid, respectively washing the obtained solid with methanol and water for 3 times, and carrying out vacuum drying at 30 ℃ overnight to obtain the photocatalyst CP/HAp.

The photocatalytic test is carried out under 32W white light, the pH value of 50mL of 50mg/L tetracycline solution is adjusted to 9 at room temperature, 100mg of CP/HAp is added, the reaction system is firstly stirred for 30min under the dark condition, and then the reaction system is reacted for 10min under the illumination of a 32W white light lamp. Each group was set up with 3 parallel experiments. Samples were taken every 5min in the dark and every 2min in the light. The samples were tested by HPLC in the same manner as in example 2.

The detection result shows that the degradation rate of the tetracycline reaches 98.92 percent. However, in repeated tests, the degradation rates are respectively found as follows: 98.82%, 67.91%, 48.59%. As shown in fig. 9, the degradation rate in repeated use is in a significantly decreasing trend. Indicating that CP/HAp has no good reusability.

[ example 15 ]

The photocatalysis test is carried out under 32W white light, 50mL of 50mg/L amoxicillin solution is added into 100mg HARCP/HAp at room temperature, the reaction system is firstly stirred for 30min under the dark condition, and then the reaction is carried out for 3h under the illumination of 32W white light. Each group was set up with 3 parallel experiments. Samples were taken every 30min in the dark and every 30min in the light. The sample was tested by HPLC, the mobile phase was acetonitrile: 0.05M phosphate buffer 2.5:97.5 at a flow rate of 1mL/min, a detection wavelength of 254nm, and a column temperature of 25 ℃.

The detection result shows that the degradation rate of amoxicillin reaches 86.38%.

[ example 16 ]

The photocatalysis test is carried out under 32W white light, 50mL of 50mg/L sulfadiazine solution is added into 100mg HARCP/HAp at room temperature, the reaction system is firstly stirred for 30min under the dark condition, and then the reaction is carried out for 3h under the illumination of 32W white light. Each group was set up with 3 parallel experiments. Samples were taken every 30min in the dark and every 30min in the light. The sample was tested by HPLC, the mobile phase was acetonitrile: water (containing 0.1 wt% phosphoric acid) at a flow rate of 1mL/min at a detection wavelength of 270nm and a column temperature of 25 ℃.

The detection result shows that the degradation rate of sulfadiazine reaches 79.19 percent.

[ example 17 ]

The photocatalytic test is carried out under 32W white light, 50mL of 50mg/L trimethoprim solution is added into 100mg HARCP/HAp at room temperature, the reaction system is firstly stirred for 30min under the dark condition and then reacts for 3h under the illumination of a 32W white light lamp. Each group was set up with 3 parallel experiments. Samples were taken every 30min in the dark and every 30min in the light. The sample was tested by HPLC, the mobile phase was acetonitrile: water (containing 0.1 wt% phosphoric acid) at a flow rate of 1mL/min at a detection wavelength of 245nm and a column temperature of 25 ℃.

The detection result shows that the degradation rate of the trimethoprim reaches 82.36%.

[ example 18 ]

The photocatalytic test is carried out under 32W white light, 50mL of 50mg/L ciprofloxacin solution is added into 100mg HARCP/HAp at room temperature, a reaction system is firstly stirred for 30min under the dark condition, and then the reaction is carried out for 3h under the illumination of a 32W white light lamp. Each group was set up with 3 parallel experiments. Samples were taken every 30min in the dark and every 30min in the light. The sample was tested by HPLC, the mobile phase was acetonitrile: water (containing 0.1 wt% phosphoric acid) at a flow rate of 1mL/min at a detection wavelength of 278nm and a column temperature of 25 ℃.

The detection result shows that the degradation rate of the ciprofloxacin reaches 96.18%.

[ example 19 ]

The photocatalytic test is carried out under 32W white light, 50mL of 50mg/L erythromycin solution is added into 100mg of HARCP/HAp at room temperature, the reaction system is firstly stirred for 30min under the dark condition, and then the reaction is carried out for 3h under the illumination of 32W white light. Each group was set up with 3 parallel experiments. Samples were taken every 30min in the dark and every 30min in the light. The sample was tested by HPLC, the mobile phase was acetonitrile: 0.067M ammonium dihydrogen phosphate 42:58 at a flow rate of 1mL/min, a detection wavelength of 210nm, and a column temperature of 25 ℃.

The detection result shows that the degradation rate of the erythromycin reaches 87.34%.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. a method for preparing organic composite photocatalyst is characterized in that, described method is: take cercosporin as raw material, carry out reductive acetylation modification to cercosporin to obtain hexaacetyl cercosporin, and then The hexaacetylcercosporin is loaded on the hydroxyapatite to obtain the supported photocatalyst hexaacetylcercosporin/hydroxyapatite.

2. method according to claim 1, is characterized in that, the method that described cercosporin carries out reductive acetylation modification is: cercosporin, acetic anhydride, magnesium powder, N,N-dimethyl- 4-aminopyridine is added to the reaction vessel, and the reaction is stirred for 1 to 3 hours; after the reaction is completed, acetic anhydride is added again, and the reaction is continued to be stirred for 1 to 3 hours; after the reaction is completed, an extractant is added for extraction, and then filtered, and the filtrate is concentrated and separated to obtain Hexaacetyl-reduced cercosporin.

3. method according to claim 1, is characterized in that, the method that hexaacetylcercosporin is loaded on hydroxyapatite is:

Weigh Cercospora hexaacetyl and dissolve it in an organic solvent. After it is completely dissolved, add hydroxyapatite. After stirring and reacting, a solid is obtained by suction filtration. The obtained solid is washed and dried to obtain a supported photocatalyst hexaacetyl. Cycerosporin/hydroxyapatite.

4. The method according to claim 3, wherein the organic solvent is any one of methanol, ethanol, dichloromethane, ethyl acetate or acetonitrile.

The method according to claim 3, wherein the mass ratio of the hexaacetylcercosporin and the hydroxyapatite is 1:(10-1000).

6. method according to claim 3 is characterized in that, the time of described stirring reaction is 5-48h.

7. The supported photocatalyst hexaacetylcercosporin/hydroxyapatite prepared according to the method of any one of claims 1-6.

8. A method for degrading antibiotics, characterized in that, the supported photocatalyst hexaacetylcercosporin/hydroxyapatite described in claim 7 is used for degradation as a catalyst.

9. method according to claim 8, is characterized in that, described antibiotic is the penicillin of tetracycline, beta-lactam, amoxicillin, ampicillin, cephalexin, cefixime; Methoxazole, trimethoprim; quinolones norfloxacin, ofloxacin, ciprofloxacin, sparfloxacin; macrolides erythromycin, azithromycin.

10. method according to claim 8 or 9, is characterized in that, the method in degrading antibiotic is:

The supported photocatalyst HARCP/HAp was put into the sewage containing antibiotics, and the continuous degradation reaction was carried out under the irradiation of visible light.