阅读说明：本技术 一种活化过硫酸盐高效降解水中微污染物糖精的方法 (Method for efficiently degrading micro-pollutant saccharin in water by activating persulfate ) 是由 马晓雁 金雨鸿 刘章华 邓靖 于 2021-07-28 设计创作，主要内容包括：本发明涉及水处理领域,特别是涉及一种活化过硫酸盐高效降解水中微污染物糖精的方法。所述方法是以降低水环境中人工甜味剂糖精为目标,使用UV/PS降解体系对水中微污染物糖精进行处理,通过UV辐照催化分解过硫酸钠,产生氧化性极强的SO-(4)～(-)·,从而使水环境中的持久性有机物糖精分解或矿化,可有效去除水中的糖精。本发明操作简单方便,过硫酸钠价格低廉、绿色环保,且体系中未引入有毒有害物质,具有安全性与实用性的特点。(The invention relates to the field of water treatment, in particular to a method for efficiently degrading micro-pollutant saccharin in water by activating persulfate. The method aims at reducing saccharin as an artificial sweetener in water environment, treats saccharin as a micropollutant in water by using a UV/PS degradation system, and catalytically decomposes sodium persulfate through UV irradiation to generate SO with strong oxidizability 4 ‑ Thereby decomposing or mineralizing the persistent organic saccharin in the water environment and effectively removing the saccharin in the water. The method is simple and convenient to operate, the sodium persulfate is low in price, green and environment-friendly, and the systemNo toxic and harmful substances are introduced, and the method has the characteristics of safety and practicability.)

1. A method for efficiently degrading saccharin serving as a micro-pollutant in water by activating persulfate is characterized by comprising the following steps:

s1, preparing a mixed solution: adding sodium persulfate into water containing saccharin to obtain mixed solution;

and S2, placing the mixed solution under the irradiation of a UV light source, and reacting at a certain temperature.

2. The method for efficiently degrading saccharin, a micro-pollutant in water, by activating persulfate according to claim 1, wherein the concentration of sodium persulfate in the mixed liquor in the S1 is 0.21-4 mM.

3. The method for efficiently degrading the micro-pollutant saccharin in water by using the activated persulfate according to claim 1, wherein the concentration of saccharin in the mixed liquor in the S1 is 0.05-0.220 mM.

4. The method for efficiently degrading saccharin, a micro-pollutant in water, by activating persulfate according to claim 1, wherein the pH value of the mixed solution in S1 is 5-9.

5. The method for efficiently degrading saccharin, a micro-pollutant in water by using the activated persulfate according to claim 1, wherein a UV light source in S2 is an 11-w low-pressure mercury lamp.

6. The method for efficiently degrading saccharin as a micro-pollutant in water by using the activated persulfate according to claim 1, wherein the UV intensity of a UV light source in S2 is 1.25nW/cm²And the wavelength is 254 nm.

7. The method for efficiently degrading saccharin, a micro-pollutant in water, by activating persulfate according to claim 1, wherein the reaction mode in S2 is stirring reaction, and the stirring speed is 100-500 r/min.

8. The method for efficiently degrading saccharin, a micro-pollutant in water, by using the activated persulfate according to claim 1, wherein the reaction temperature in the S2 is 15-25 ℃, and the reaction time is 0.5-2 h.

9. The method for efficiently degrading saccharin, a micro-pollutant in water by using the activated persulfate according to claim 1, wherein the S2 is obtained by assembling a UV device reactor and placing an S1 mixed liquor into the UV device reactor for reaction.

10. The method for efficiently degrading saccharin, a micro-pollutant in water, by activating persulfate according to claim 9, wherein the UV device reactor comprises a UV light source, a reaction vessel and a constant-temperature stirrer, the reaction vessel is placed in the constant-temperature stirrer, the UV light source can irradiate the reaction vessel, and the mixed solution is placed in the reaction vessel.

Technical Field

The invention relates to the field of water treatment, in particular to a method for degrading saccharin, a novel pollutant in water.

Background

Saccharin is an artificial sweetener with the longest application time and the widest application range, and has low price and sweetness about 500 times that of common sucrose. Saccharin has now been approved in more than 90 countries for its wide use in pharmacy, food processing and aquaculture feed production, as a cure accelerator for anaerobic adhesives and as a co-accelerator for unsaturated polyester resins, and as a brightener in nickel plating.

In recent years, the safety of saccharin application is questioned, and saccharin is reported to influence the gastrointestinal absorption function, and has potential risks in biotoxicity, and the dosage of saccharin needs to be strictly controlled. Saccharin can not be metabolized or absorbed in a human body, is usually discharged into a sewage collecting and treating system as a pollutant after use, and is not high in removal effect and slow in removal effect by a sewage treatment process mainly based on biological treatment. Saccharin enters a received water environment along with emission, and is one of the main approaches for water environment pollution.

Saccharin has a certain persistence, presents low harmfulness and potential risks to aquatic plants, and is a novel environmental pollutant. According to the report, the concentration of saccharin detected in sewage and surface water environment is about several to dozens of mug/L, saccharin in a water source can penetrate through a conventional drinking water treatment process, and the subsequent advanced treatment process such as ozone oxidation and ultraviolet sterilization has poor saccharin removal effect. Saccharin inevitably enters a drinking water system, and influences the safety of drinking water quality.

In order to effectively solve the problems of high organic matters and trace organic pollution in water sources, advanced treatment process transformation is gradually carried out in domestic water plants, and pre-oxidation is one of the most common advanced treatment technical means. However, the prior art still lacks an effective method for treating saccharin.

Disclosure of Invention

The invention aims to provide a method for removing a micro-pollutant saccharin in a water environment by using an ultraviolet light/persulfate combined process, which aims to reduce the saccharin serving as an artificial sweetener in the water environment, uses a UV/PS (ultraviolet/polystyrene) degradation system to treat the micro-pollutant saccharin in the water, and provides a new way for treating the saccharin.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a method for efficiently degrading saccharin, a micro-pollutant in water, by activating persulfate comprises the following steps:

s1, preparing a mixed solution: adding sodium persulfate SPS into water containing saccharin to obtain mixed solution;

and S2, placing the mixed solution under the irradiation of a UV light source, and reacting at a certain temperature.

Preferably, in step S1, sodium persulfate is added to the saccharin-containing water in the form of a sodium persulfate solution to obtain a mixed solution.

Preferably, the concentration of the sodium persulfate SPS in the mixed solution in the S1 is 0.21-4.00 mM, more preferably 0.21-2.52 mM, and still more preferably 1.05 mM.

Preferably, the concentration of saccharin in the mixed solution of S1 is 0.055-0.220 mM, more preferably 0.055-0.220 mM, and even more preferably 0.11 mM.

Preferably, the pH of the mixed solution in S1 is 5 to 9, and more preferably, the pH of the mixed solution is adjusted by using a phosphate buffer.

Preferably, the reaction is carried out in S2 under protection from light, ensuring that the reaction is carried out only under UV irradiation.

Preferably, the UV light source in S2 is an 11w low-pressure mercury lamp.

Preferably, the UV intensity of the UV light source in S2 is 1.25nW/cm²And the wavelength is 254 nm.

Preferably, the reaction mode in S2 is a stirring reaction, the stirring speed is 100-500r/min, and the more preferred stirring speed is 200 r/min.

Preferably, the reaction temperature in the S2 is 15-25 ℃, and the reaction time is 0.5-2 h; more preferably, the reaction temperature is 20 ℃ and the reaction time is 1 hour.

Preferably, in the step S2, the reaction is performed by assembling a UV device reactor and placing the S1 mixed solution in the UV device reactor; more preferably, the UV device reactor comprises a UV light source, a reaction container, and a constant temperature stirrer, the reaction container is placed in the constant temperature stirrer, the UV light source can irradiate the reaction container, and the mixed solution is placed in the reaction container; more preferably, the outer wall of the reaction vessel is further pasted with tinfoil paper to isolate ultraviolet rays, so that the reaction is ensured to be in a light-tight condition, and only ultraviolet rays are irradiated in the reaction vessel for reaction; more preferably, the constant-temperature stirrer is a water bath constant-temperature magnetic stirrer, and the reaction vessel is placed in the water bath constant-temperature magnetic stirrer.

Preferably, the UV unit reactor in S2 is preheated for 15min to ensure a stable UV output.

And HO (E)₀1.8-2.7V and 10^-3μ s half life) of sulfate radical (SO)₄ ^-Has a higher redox potential (E) at neutral pH₀2.65-3.1V), longer half-life period (30-40 mu s) and better oxidation selectivity. SO (SO)₄ ^-Can be generated by heat, ultrasonic irradiation, electrochemical processes, ultraviolet photolysis, and transition metal ion activation of persulfate. The ultraviolet light/persulfate (UV/PS) is simple in equipment and low in energy consumption, and does not cause heavy metal pollution.

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention uses UV advanced oxidation technology to generate SO with strong oxidability by catalytically decomposing sodium persulfate₄ ^-Thereby decomposing or mineralizing the persistent organic saccharin in the water environment, and effectively removing the saccharin in the water with the removal rate up to 100 percent.

(2) The removal rate of saccharin under different pH conditions is at least 80%, and the saccharin has good removal effect, wherein the pH range is 5-9.

(3) The method has the characteristics of simple and convenient operation, low price of sodium persulfate, environmental protection, no toxic and harmful substances introduced into the system, safety and practicability.

Drawings

FIG. 1: is a schematic diagram of a UV reactor of the present invention;

FIG. 2: the degradation effect of the UV/PS system and the single UV and the single PS on saccharin in the case of the invention is compared;

FIG. 3: the degradation effect diagram of the UV/PS system on saccharin under different solution pH conditions is shown;

FIG. 4: the degradation effect diagram of the UV/PS system on saccharin under the condition of different saccharin concentrations is shown;

FIG. 5: the degradation effect of the UV/PS system on saccharin under the condition of different persulfate adding amounts is shown in the figure;

FIG. 6: a graph illustrating the degree of mineralization of saccharin by the UV/PS system of the present invention is shown.

Detailed Description

The technical solution of the present invention is further specifically described below by way of specific examples in conjunction with the accompanying drawings. The following examples are merely illustrative of the present invention and should not be construed as limiting the scope of the invention. The reagents or instruments are not indicated by manufacturers, and are all conventional products which can be purchased through normal channels.

Example 1 degradation of saccharin by UV/PS degradation System

The degradation experiment of saccharin by UV/PS degradation system comprises the following steps of carrying out reaction under the conditions that the initial concentration of saccharin is 0.11mM (mM ═ mmol/L) sodium persulfate is added in an amount of 1.05mM, the temperature is 20 +/-0.5 ℃, and the pH value is 7.0 +/-0.2:

s1, preparing a mixed solution. First, a 1g/L saccharin stock solution and a 125g/L sodium persulfate solution were prepared and the concentrations were calibrated by spectrophotometry. 10mL of saccharin stock solution and 1mL of sodium persulfate solution are taken to prepare a mixed solution, 0.2M of phosphate buffer solution is adopted to adjust the pH value to 7, the volume is determined to be 500mL, and a magnetic stirrer is used for uniformly mixing the solution. The resulting mixture had an initial saccharin concentration of 0.11mM and a sodium persulfate concentration of 1.05 mM.

And S2, constructing a UV device reactor. The saccharin degradation test was carried out in a cylindrical glass reactor having a diameter of 7.5cm and a height of 22cm, and a UV intensity of 1.25nW/cm²The ultraviolet lamp with the wavelength of 254nm and the wavelength of 11w is arranged in the center of the reactor, the outer wall of the reactor is pasted with tinfoil paper to isolate ultraviolet rays, the ultraviolet irradiation is ensured to be reacted under the condition of light shielding, the reactor is arranged in a water bath constant temperature magnetic stirrer, and the internal solution realizes uniform reaction through magnetic stirring.

S3, placing the mixed liquid in the S1 in a UV device reactor for reaction. Transferring the mixed solution into a reaction container, controlling the reaction temperature to be 20 ℃ by a water bath constant-temperature magnetic stirrer, and starting magnetic stirring to uniformly mix the solution, wherein the stirring speed is 200 r/min. An ultraviolet lamp (preheated for 15min) is placed in the center of the reactor to start the reaction.

And S4, sampling at certain reaction intervals, and detecting and analyzing. 1mL of sample was taken at 0, 2, 5, 10, 15, 20, 30, 45 and 60min of reaction, respectively, filtered through a 0.45 μm filter and placed in a sample vial to which a sufficient amount (0.1mL) of quencher (methanol) was previously added, and analyzed by liquid chromatography.

S5, and a saccharin detection method. A liquid chromatograph is adopted for sample analysis, the detection method is a conventional technical means in the field, and the method comprises the following steps: the chromatographic column is an inert sustatin C18 column (5 μm × 4.6mm × 250mm), the wavelength is 218nm, the mobile phase is a mixed solution of ammonium acetate and methanol according to a volume ratio of 85:15, the flow rate is 1.0mL/min, and the sample injection amount is 20 μ L.

The UV/PS system follows first order reaction kinetics for the degradation process of saccharin, under which conditions saccharin removal over time is shown in figure 2 as UV/PS.

Comparative example 1 degradation of saccharin by UV alone

Degradation of saccharin by UV alone was tested at an initial concentration of saccharin of 0.11mM, a temperature of 20. + -. 0.5 ℃ and a pH of 7.0. + -. 0.2.

The method specifically comprises the following steps:

s1, preparing saccharin solution. First, a saccharin stock solution of 1g/L is prepared and the concentration is calibrated by a spectrophotometer method. Taking 10mL of saccharin stock solution to prepare a solution, adjusting the pH value to 7 by adopting 0.2M phosphate buffer solution, metering to 500mL, and uniformly mixing the solution by using a magnetic stirrer. The resulting solution had an initial concentration of saccharin of 0.11 mM.

And S2, constructing a UV device reactor. The saccharin degradation test is carried out in a cylindrical glass reactor with the diameter of 7.5cm and the height of 22cm, an ultraviolet lamp with the wavelength of 254nm and 11w is arranged in the center of the reactor, tinfoil paper is pasted on the outer wall of the reactor to isolate ultraviolet rays, the reactor is arranged in a water bath constant-temperature magnetic stirrer, and the internal solution is stirred by magnetic force to realize uniform reaction.

S3, placing the saccharin solution in the S1 in a UV device reactor for reaction. Transferring the saccharin solution into a reaction vessel, controlling the reaction temperature to be 20 ℃ by a water bath constant-temperature magnetic stirrer, and starting magnetic stirring. An ultraviolet lamp (preheated for 15min) is placed in the center of the reactor to start the reaction.

And S4, sampling at certain reaction intervals, and detecting and analyzing. 1mL of sample was taken at 0, 2, 5, 10, 15, 20, 30, 45 and 60min of reaction, respectively, filtered through a 0.45 μm filter and placed in a sample vial to which a sufficient amount (0.1mL) of quencher (methanol) was previously added, and analyzed by liquid chromatography.

S5, and a saccharin detection method. A liquid chromatograph is adopted for sample analysis, an ultraviolet detector is adopted for detection, the wavelength is 218nm, the mobile phase is a mixed solution of ammonium acetate and methanol according to the volume ratio of 85:15, the flow rate is 1.0mL/min, and the sample injection amount is 20 mu L.

The degradation process of saccharin by UV alone follows first order reaction kinetics, under which saccharin removal over time is shown as UV in figure 2.

Comparative example 2 degradation of saccharin by PS alone

Degradation of saccharin by PS alone was tested at an initial concentration of saccharin of 0.11mM, sodium persulfate at a dose of 1.05mM, a temperature of 20. + -. 0.5 ℃ and a pH of 7.0. + -. 0.2.

The method specifically comprises the following steps:

s1, preparing a mixed solution. First, a 1g/L saccharin stock solution and a 125g/L sodium persulfate solution were prepared and the concentrations were calibrated by spectrophotometry. 10mL of saccharin stock solution and 1mL of sodium persulfate solution are taken to prepare a mixed solution, 0.2M of phosphate buffer solution is adopted to adjust the pH value to 7, the volume is determined to be 500mL, and a magnetic stirrer is used for uniformly mixing the solution. The resulting mixture had an initial saccharin concentration of 0.11mM and a sodium persulfate concentration of 1.05 mM.

And S2, constructing a reactor. The saccharin degradation test is carried out in a cylindrical glass reactor with the diameter of 7.5cm and the height of 22cm, the outer wall of the reactor is pasted with tinfoil paper to isolate ultraviolet rays, a foam plate wrapped by the tinfoil paper is covered at the top of the reactor, the reactor is placed in a water bath constant-temperature magnetic stirrer, and the internal solution is stirred by magnetic force to realize uniform reaction.

S3, placing the mixed liquid in the S1 into a reactor for reaction. Transferring the mixed solution into a reaction container, controlling the reaction temperature to be 20 ℃ by a water bath constant-temperature magnetic stirrer, starting magnetic stirring to uniformly mix the solution, and starting reaction.

And S4, sampling at certain reaction intervals, and detecting and analyzing. 1mL of sample was taken at 0, 2, 5, 10, 15, 20, 30, 45 and 60min of reaction, respectively, filtered through a 0.45 μm filter and placed in a sample vial to which a sufficient amount (0.1mL) of quencher (methanol) was previously added, and analyzed by liquid chromatography.

S5, and a saccharin detection method. A liquid chromatograph is adopted for sample analysis, an ultraviolet detector is adopted for detection, the wavelength is 218nm, the mobile phase is a mixed solution of ammonium acetate and methanol according to the volume ratio of 85:15, the flow rate is 1.0mL/min, and the sample injection amount is 20 mu L.

The saccharin removal effect over time for the PS alone system under this condition is shown as PS in figure 2.

EXAMPLE 2 degradation of saccharin by UV/PS systems at different solution pH conditions

Degradation experiments of saccharin by UV/PS degradation systems under different pH conditions of solutions were carried out at an initial concentration of 0.11mM saccharin, an amount of 1.05mM sodium persulfate added, and a temperature of 20. + -. 0.5 ℃.

The method specifically comprises the following steps:

s1, preparing a mixed solution. First, a 1g/L saccharin stock solution and a 125g/L sodium persulfate solution were prepared and the concentrations were calibrated by spectrophotometry. 10mL of saccharin stock solution and 1mL of sodium persulfate solution are respectively taken to prepare mixed solution, 0.2M phosphate buffer solution is adopted to adjust the pH value to 5, 6, 7, 8 and 9, the volume is adjusted to 500mL, and a magnetic stirrer is used for uniformly mixing the solution. The resulting mixture had an initial saccharin concentration of 0.11mM and a sodium persulfate concentration of 1.05 mM.

And S2, constructing a UV device reactor. The saccharin degradation test is carried out in a cylindrical glass reactor with the diameter of 7.5cm and the height of 22cm, an ultraviolet lamp with the wavelength of 254nm and 11w is arranged in the center of the reactor, tinfoil paper is pasted on the outer wall of the reactor to isolate ultraviolet rays, the reactor is arranged in a water bath constant-temperature magnetic stirrer, and the internal solution is stirred by magnetic force to realize uniform reaction.

S3, placing the mixed liquid in the S1 in a UV device reactor for reaction. Transferring the mixed solution into a reaction container, controlling the reaction temperature to be 20 ℃ by a water bath constant-temperature magnetic stirrer, and starting magnetic stirring to uniformly mix the solution. An ultraviolet lamp (preheated for 15min) is placed in the center of the reactor to start the reaction.

And S4, sampling at certain reaction intervals, and detecting and analyzing. 1mL of sample was taken at 0, 2, 5, 10, 15, 20, 30, 45 and 60min of reaction, respectively, filtered through a 0.45 μm filter and placed in a sample vial to which a sufficient amount (0.1mL) of quencher (methanol) was previously added, and analyzed by liquid chromatography.

S5, and a saccharin detection method. A liquid chromatograph is adopted for sample analysis, an ultraviolet detector is adopted for detection, the wavelength is 218nm, the mobile phase is a mixed solution of ammonium acetate and methanol according to the volume ratio of 85:15, the flow rate is 1.0mL/min, and the sample injection amount is 20 mu L.

The degradation process of saccharin by the UV/PS system follows first order reaction kinetics, and the removal effect of saccharin over time under these conditions is shown in FIG. 3. As can be seen from the figure, the removal rate of saccharin under different pH conditions is over 80 percent.

Example 3 degradation of saccharin by UV/PS systems at various initial saccharin concentrations

The degradation experiment of the UV/PS degradation system on saccharin under the condition of different saccharin initial concentration is carried out under the conditions that the adding amount of sodium persulfate is 1.05mM, the temperature is 20 +/-0.5 ℃, and the pH value is 7.0 +/-0.2.

The method specifically comprises the following steps:

s1, preparing a mixed solution. First, a 1g/L saccharin stock solution and a 125g/L sodium persulfate solution were prepared and the concentrations were calibrated by spectrophotometry. Respectively taking 5-40 mL of saccharin stock solution and 1mL of sodium persulfate solution to prepare mixed solution, adjusting the pH value to 7 by adopting 0.2M of phosphate buffer solution, fixing the volume to 500mL, and uniformly mixing the solution by using a magnetic stirrer. The resulting mixture had an initial concentration of saccharin of 0.055, 0.082, 0.110, 0.164 or 0.220mM and a concentration of sodium persulfate of 1.05 mM.

And S2, constructing a UV device reactor. The saccharin degradation test is carried out in a cylindrical glass reactor with the diameter of 7.5cm and the height of 22cm, an ultraviolet lamp with the wavelength of 254nm and 11w is arranged in the center of the reactor, tinfoil paper is pasted on the outer wall of the reactor to isolate ultraviolet rays, the reactor is arranged in a water bath constant-temperature magnetic stirrer, and the internal solution is stirred by magnetic force to realize uniform reaction.

S3, placing the mixed liquid in the S1 in a UV device reactor for reaction. Transferring the mixed solution into a reaction container, controlling the reaction temperature to be 20 ℃ by a water bath constant-temperature magnetic stirrer, and starting magnetic stirring to uniformly mix the solution. An ultraviolet lamp (preheated for 15min) is placed in the center of the reactor to start the reaction.

And S4, sampling at certain reaction intervals, and detecting and analyzing. 1mL of sample was taken at 0, 2, 5, 10, 15, 20, 30, 45 and 60min of reaction, respectively, filtered through a 0.45 μm filter and placed in a sample vial to which a sufficient amount (0.1mL) of quencher (methanol) was previously added, and analyzed by liquid chromatography.

S5, and a saccharin detection method. A liquid chromatograph is adopted for sample analysis, an ultraviolet detector is adopted for detection, the wavelength is 218nm, the mobile phase is a mixed solution of ammonium acetate and methanol according to the volume ratio of 85:15, the flow rate is 1.0mL/min, and the sample injection amount is 20 mu L.

The degradation process of saccharin by the UV/PS system under the condition of different saccharin initial concentrations accords with first-order reaction kinetics, and the removal effect of saccharin along with time under the condition is shown in figure 4.

Example 4 degradation of saccharin by UV/PS systems at various persulfate dosing levels

The degradation experiment of the saccharin by the UV/PS degradation system under the condition of different persulfate adding amounts is carried out under the conditions that the initial concentration of the saccharin is 0.11mM, the temperature is 20 +/-0.5 ℃, and the pH value is 7.0 +/-0.2.

The method specifically comprises the following steps:

s1, preparing a mixed solution. First, a 1g/L saccharin stock solution and a 125g/L sodium persulfate solution were prepared and the concentrations were calibrated by spectrophotometry. Respectively taking 10mL of saccharin stock solution and 0.2-2.4 mL of sodium persulfate solution to prepare mixed solution, adjusting the pH value to 7 by adopting 0.2M of phosphate buffer solution, fixing the volume to 500mL, and uniformly mixing the solution by using a magnetic stirrer. The resulting mixture had an initial saccharin concentration of 0.11mM and sodium persulfate concentrations of 0.21, 0.42, 1.05, 1.68, and 2.52 mM.

And S2, constructing a UV device reactor. The saccharin degradation test is carried out in a cylindrical glass reactor with the diameter of 7.5cm and the height of 22cm, an ultraviolet lamp with the wavelength of 254nm and 11w is arranged in the center of the reactor, tinfoil paper is pasted on the outer wall of the reactor to isolate ultraviolet rays, the reactor is arranged in a water bath constant-temperature magnetic stirrer, and the internal solution is stirred by magnetic force to realize uniform reaction.

S3, placing the mixed liquid in the S1 in a UV device reactor for reaction. Transferring the mixed solution into a reaction container, controlling the reaction temperature to be 20 ℃ by a water bath constant-temperature magnetic stirrer, and starting magnetic stirring to uniformly mix the solution. An ultraviolet lamp (preheated for 15min) is placed in the center of the reactor to start the reaction.

And S4, sampling at certain reaction intervals, and detecting and analyzing. 1mL of sample was taken at 0, 2, 5, 10, 15, 20, 30, 45 and 60min of reaction, respectively, filtered through a 0.45 μm filter and placed in a sample vial to which a sufficient amount (0.1mL) of quencher (methanol) was previously added, and analyzed by liquid chromatography.

S5, and a saccharin detection method. A liquid chromatograph is adopted for sample analysis, an ultraviolet detector is adopted for detection, the wavelength is 218nm, the mobile phase is a mixed solution of ammonium acetate and methanol according to the volume ratio of 85:15, the flow rate is 1.0mL/min, and the sample injection amount is 20 mu L.

The degradation process of saccharin by the UV/PS system under the condition of different persulfate adding amounts accords with first-order reaction kinetics, and the removal effect of saccharin along with time under the condition is shown in figure 5.

In summary, the present application generates sulfate radicals (SO) by activating persulfate with UV₄ ^-HO.) and hydroxyl radical (HO.) in a UV/PS system, the UV-light activation of PS produces SO₄ ^-(reactions (1-1) to (1-3)), SO₄ ^-Can be converted into HO. (reaction (1-5)), and a series of reactions take place in the UV/PS system (reactions (1-6) to (1-11)).And saccharin is removed through strong oxidizing property of free radicals and synergistic effect of the free radicals and the saccharin.

The invention has the advantages of simple process device, stable and quick reaction, quick reaction at normal temperature and normal pressure, strong operability, no secondary pollution and reduced labor intensity and cost.

The above-described embodiments are merely preferred embodiments of the present invention, which is not intended to be limiting in any way, and other variations and modifications are possible without departing from the scope of the invention as set forth in the appended claims.