CN106186277A - A kind of method utilizing potassium hydrogen persulfate to remove sulfamethoxazole and application thereof - Google Patents

Abstract

The invention discloses a method for removing sulfamethoxazole (SMX) by using potassium hydrogen persulfate (Oxone) and an application thereof. The method comprises: under certain experimental conditions, adding Oxone into the SMX solution and stirring at room temperature. The present invention finds for the first time that Oxone can quickly and efficiently remove SMX under the condition of large changes in experimental conditions. The technical process of the invention is easy to operate, does not require high equipment, Oxone is easy to obtain, and is convenient for transportation and storage, and has broad market application prospects in the aspect of removing antibiotics in water environment.

Description

A kind of method utilizing potassium hydrogen persulfate to remove sulfamethoxazole and its application

technical field

The invention belongs to the fields of water pollution control technology and advanced oxidation technology, and relates to a method for removing sulfamethoxazole by using potassium hydrogen persulfate.

Background technique

Antibiotic pollution in the environment has been a topic of common concern to domestic and foreign researchers in recent years. Sulfamethoxazole (SMX) is one of the refractory antibiotics. Under the long-term action of low-concentration SMX, microorganisms in water will develop drug resistance, and then domesticate "super bacteria", which will endanger the health of humans and ecosystems; traditional The water treatment process cannot completely remove SMX, so it is necessary to develop a treatment technology for rapid and efficient degradation of SMX.

Adsorption and microbial degradation are currently reported technologies for treating SMX in water environment. For example, the patent No. CN201310492851.8, CN201410472549.0 and CN201510874630.6 respectively reported the method of using straw charcoal, modified bamboo charcoal and porous molecular sieve filter media to adsorb and retain SMX in water, while the patent No. CN201210337053.3 used biological flocculant treatment SMX. Adsorption and microbial degradation are limited in the actual treatment of SMX in the water environment due to the failure to remove SMX and the long treatment period. Advanced oxidation technology is a new type of technology that can rapidly oxidize and degrade SMX. Its action process is to remove organic pollution through the strong oxidizing active substances (such as ^• OH and SO ₄ ^•− ) produced during the reaction process or the strong oxidizing properties of the agent itself. effectively mineralizes and removes substances.

Compared with O ₃ , H ₂ O ₂ , chlorine and TiO ₂ -based oxidation technologies, persulfate oxidation technology is a new type of advanced oxidation technology developed in recent years. At present, this technology mainly uses persulfate and S ₂ O ₈ ^2- base salt decomposes to produce strong oxidative SO ₄ ^•− free radicals to degrade organic pollutants in water. Cai Meifang et al. used Co ²⁺ loaded reagents to activate potassium hydrogen persulfate to generate active SO ₄ ^•− to degrade SMX, and 0.1 mM SMX was completely degraded and removed within 12 minutes (Cai Meifang, heterogeneously catalyzed degradation of typical antibiotics by hydrogen persulfate[ D], Dalian University of Technology, 2012); In addition, Wang's research group reported for the first time the process of oxidative degradation of organic pollutants based on nano-carbon activation of potassium hydrogen persulfate (Chem. Commun., 2013, 49: 9914).

Oxone is a granular white powder with good fluidity. It is a unique triple salt composed of potassium monoperoxyhydrogensulfate (KHSO ₅ ), potassium hydrogensulfate (KHSO ₄ ) and potassium sulfate (K ₂ SO ₄ ). The active ingredient is KHSO ₅ . Oxone is widely used as an oxidant for environmental remediation due to its stable properties, easy transportation and storage, and low cost. The results of literature search showed that the method of directly applying Oxone to remove SMX has not been reported yet. The present invention finds for the first time that Oxone can efficiently remove SMX in water.

Contents of the invention

The main purpose of the invention is to overcome the deficiencies in the prior art and provide a method for utilizing potassium persulfate to remove sulfamethoxazole.

The object of the present invention is achieved through the following technical routes: a method utilizing potassium hydrogen persulfate to remove sulfamethoxazole, characterized in that: under certain experimental conditions, Oxone is added to the SMX solution and stirred at room temperature.

The molecular formula of the Oxone is KHSO ₅ •0.5KHSO ₄ •0.5K ₂ SO ₄ , the molecular weight is 307.38, and the KHSO ₅ content is ≥47%.

The experimental conditions are adjusted by changing the dosage of Oxone, the concentration of SMX solution, the initial pH of SMX solution, and the concentration of anion or quencher in the reaction solution.

The dosage of Oxone is preferably 3.0-6.0 mM.

The concentration of the SMX solution is preferably 2.5-12.5 mg/L.

The initial pH of the SMX solution is preferably 2.50-10.50.

The anions include NO ₃ ⁻ , Cl ⁻ , SO ₄ ²⁻ and HCO ₃ ⁻ , the concentrations of which are preferably 0-10 mM, 0-10 mM, 0-10 mM and 0-8 mM respectively.

The quenching agent includes methanol and tert-butanol, and the concentration thereof is preferably 0-0.5 M.

The stirring parameter is preferably 300 rpm for 5-80 min.

The present invention has the following advantages and effects.

(1) The present invention found for the first time that Oxone can efficiently remove SMX, and can maintain a high removal rate (both greater than 93%) under the condition of large changes in solution parameters.

(2) The present invention has strong operability, and the reaction can be carried out at normal temperature and pressure, and the requirements for equipment are not high.

(3) The Oxone used in the present invention is cheap and easy to obtain, and is easy to store and transport, and can be widely used in the treatment of water pollution environment, and has great application prospects.

Description of drawings

Figure 1 is a schematic diagram of Oxone removal of SMX curves in water under different experimental conditions.

Figure 2 is a trend diagram of the influence of SMX concentration on the removal of SMX from water by Oxone.

Figure 3 is a trend diagram of the effect of Oxone dosage on SMX removal from water by Oxone.

Figure 4 is a trend diagram of the influence of the initial pH value of the solution on the removal of SMX from water by Oxone.

Figure 5 is a trend diagram of the influence of different anions on the removal of SMX from water by Oxone.

Figure 6 is a trend diagram of the influence of different quenchers on the removal of SMX from water by Oxone.

detailed description

The present invention will be further described in detail below through the examples and accompanying drawings (the protection scope of the present invention is not limited to the content described).

Example 1:

(1) SMX removal efficiency of Oxone in water under different operating conditions: SMX aqueous solutions with concentrations of 2.5, 5 and 12.5 mg/L were prepared, and their pH was adjusted to 2.50, 6.40 and 10.50, respectively. Measure 80 mL of SMX aqueous solution into 6 clean reaction bottles and number them, then add 3, 5 and 6 mM Oxone (Oxone is provided by Aladdin) to No. 1, 2 and 3 reaction bottles respectively, and No. No material (control sample) was added to the bottle, placed at room temperature (25 ± 2°C) and stirred (300 rpm) for 80 min, and 2 mL water samples were taken at regular intervals for analysis.

(2) Draw the obtained data into a graph as shown in Figure 1: Under different experimental conditions, Oxone can quickly and efficiently degrade and remove more than 93% of SMX in water, and the SMX self-volatility rate in the entire reaction cycle is ˂5 %. This example shows that Oxone has the ability to efficiently degrade and remove SMX in water under different experimental operating conditions, and also shows that the removal of SMX in water is mainly realized by the oxidation process of Oxone.

Example 2:

(1) To investigate the influence of SMX concentration on Oxone’s removal of SMX from water: prepare SMX aqueous solutions with a pH of 6.40 and a concentration of 2.5, 5, and 12.5 mg/L, and measure 80 mL of SMX target solution in 3 clean reaction bottles, respectively. Add 5.5 mMOxone, place it at room temperature (25 ± 2°C) and stir (300 rpm) for 80 min, and take 2 mL of water samples at regular intervals for analysis.

(2) As shown in Figure 2: when the concentration of SMX is 2.5-12.5 g/L and the concentration of Oxone is 5.5 mM, Oxone can remove more than 97% of SMX in water within 5 minutes; It was detected, indicating that Oxone can degrade and remove SMX efficiently and rapidly in the case of large changes in SMX concentration.

Example 3:

(1) Investigate the influence trend of Oxone dosage on Oxone removal of SMX in water: prepare SMX aqueous solution with a concentration of 4 mg/L, and adjust its pH to 6.40, take 3 clean reaction bottles and add 80 mL target solution respectively and number them, and then Add 4, 5, and 6 mMOxone respectively, place at room temperature (25 ± 2°C) and stir (300 rpm) to react for 80 min, and take 2 mL water samples at regular intervals for analysis.

(2) The obtained data was plotted into a graph as shown in Figure 3. After 5 minutes of reaction, more than 98.5% of SMX in water were effectively degraded and removed by Oxone, which indicated that Oxone had the potential to efficiently degrade SMX in water.

Example 4:

(1) Investigate the influence trend of the initial pH value of the solution on the removal of SMX from water by Oxone: Prepare a SMX aqueous solution with a concentration of 4.5 mg/L, take 5 clean reaction bottles and add 80 mL of target solution respectively and number them; The pH of the solution was adjusted to 2.50, 4.32, 6.40, 8.44, and 10.50, respectively, and then 4 mM Oxone was added, placed at room temperature (25 ± 2°C) and stirred (300 rpm) to react for 80 min, and 2 mL of water samples were taken at regular intervals for analysis.

(2) The degradation trend is shown in Figure 4. After 80 minutes of reaction, more than 95% of the SMX in the water was effectively degraded and removed by Oxone, indicating that Oxone can efficiently degrade SMX in water when the initial pH value of the solution changes greatly.

Example 5:

(1) To investigate the influence trend of different anions and quenchers on the removal of SMX from water by Oxone: Take 7 clean reaction bottles and add 80 mL of 5 mg/L SMX aqueous solution respectively and number them, and add them to reaction bottles numbered 1-4 10 mM NaNO ₃ , 10 mM Na ₂ SO ₄ , 10 mM NaCl and 8 mM NaHCO ₃ , add 0.5 M methanol and tert-butanol to reaction vials numbered 5 and 6, respectively, and add nothing to reaction vial 7; The pH of the solution was adjusted to 6.40, and then 5 mMOxone was added to the reaction bottle, placed at room temperature (25 ± 2°C) and stirred (300 rpm) to react for 80 min, and 2 mL water samples were taken at regular intervals for analysis.

(2) The obtained data were plotted into the graphs shown in Figures 5 and 6. After 5 minutes of reaction, more than 99% of SMX in the water were effectively removed by Oxone, which indicated that Oxone had high resistance to inorganic anions and quenching of SMX in water. It also shows that the removal of SMX in water by Oxone is a non-free radical-mediated degradation process.

Claims (10)

1. A method for removing sulfamethoxazole (SMX) by potassium persulfate (Oxone), characterized in that: under certain experimental conditions, Oxone is added to the SMX solution and stirred at room temperature. 2. The method for removing SMX by using Oxone according to claim 1, characterized in that: the molecular formula of the Oxone is KHSO ₅ •0.5KHSO ₄ •0.5K ₂ SO ₄ , the molecular weight is 307.38, and the KHSO ₅ content is ≥47%. 3. utilize Oxone to remove the method for SMX according to claim 1, it is characterized in that: described experimental condition is by changing the concentration of anion or quencher in Oxone dosage, SMX solution concentration, SMX solution initial pH, reaction solution adjust. 4. Oxone according to claim 1, 2 or 3, characterized in that: the dosage is 3.0-6.0 mM. 5. according to the described SMX solution of claim 1 or 3, it is characterized in that: concentration is 2.5～12.5 mg/L. 6. The SMX solution according to claim 1 or 3, characterized in that: the initial pH is 2.50-10.50. 7. The anion according to claim 3, characterized in that it includes NO ₃ ⁻ , Cl ⁻ , SO ₄ ²⁻ and HCO ₃ ⁻ , and their concentrations are 0-10 mM, 0-10 mM, 0-10 mM respectively and 0-8 mM. 8. The quencher according to claim 3, characterized in that: methanol and tert-butanol are included, and the concentrations thereof are 0-5M. 9. The method for removing SMX by using Oxone according to claim 1, characterized in that: the parameters of the stirring are 300rmp, 5-80 min. 10. the method utilizing Oxone to remove SMX according to claim 1 is applied to removing SMX in the water environment.