Search

CN-121974473-A - Method for degrading organic pollutants by utilizing pyrite and sodium hypophosphite in cooperation

CN121974473ACN 121974473 ACN121974473 ACN 121974473ACN-121974473-A

Abstract

The invention discloses a method for degrading organic pollutants by utilizing pyrite and sodium hypophosphite, belonging to the technical field of water pollution control and advanced oxidation. The method comprises the steps of ball milling pyrite, sieving, washing and drying to obtain treated pyrite, preserving the treated pyrite under anaerobic conditions, adding the treated pyrite and sodium hypophosphite into a water body containing organic pollutants, and reacting under natural light conditions to degrade the organic pollutants. According to the invention, through the synergistic effect of pyrite and sodium hypophosphite, an exogenous oxidant is not required to be added in a system for degrading organic pollutants, and free radicals can be generated only through internal reaction of the system, so that the system can still keep high degradation activity on the organic pollutants in an anaerobic or anaerobic environment, the dependence of the traditional advanced oxidation technology on dissolved oxygen is broken through, the application potential of the traditional advanced oxidation technology in-situ remediation of anoxic environments such as groundwater, bottom mud and the like is widened, and in addition, the cost is obviously reduced and the risk of secondary pollution is avoided.

Inventors

  • GAO XIAOYA
  • LUO YUE
  • LUO YONGMING
  • Hu Yaoran
  • YIN YUCHENG

Assignees

  • 昆明理工大学

Dates

Publication Date
20260505
Application Date
20260319

Claims (8)

  1. 1. A method for degrading organic pollutants by utilizing pyrite and sodium hypophosphite is characterized by comprising the following steps: (1) Sequentially ball-milling, sieving, washing and drying pyrite to obtain treated pyrite; (2) And (3) under the illumination condition, adding the treated pyrite obtained in the step (1) into the water body containing the organic pollutants to react with sodium hypophosphite, so as to degrade the organic pollutants.
  2. 2. The method for the synergistic degradation of organic pollutants by pyrite and sodium hypophosphite as claimed in claim 1, wherein in the step (1), the treated pyrite is obtained by drying and then calcining at a temperature of 200 ℃ for 2 hours.
  3. 3. The method for synergistically degrading organic pollutants by utilizing pyrite and sodium hypophosphite according to claim 1, wherein in the step (2), the amount of hypophosphorous acid substances and the ratio of the mass of the organic pollutants to the mass of the pyrite are (13-20) mmol (a-10) mg (0.1-0.3) g, and a is more than or equal to 0 and less than or equal to 10.
  4. 4. The method for the synergistic degradation of organic contaminants by pyrite and sodium hypophosphite as claimed in claim 1, wherein the organic contaminant is carbamazepine.
  5. 5. The method for the synergistic degradation of organic contaminants by pyrite and sodium hypophosphite as claimed in claim 1, wherein in said step (2), the pH of the reaction is 3 to 9.
  6. 6. A method for the synergistic degradation of organic contaminants by pyrite and sodium hypophosphite as claimed in claim 3, wherein said reaction is carried out under aerobic, anaerobic or anaerobic conditions.
  7. 7. The method of claim 6, wherein the concentration ratio of sodium hypophosphite to pyrite is (14-20) mM (0.1-0.3) g/L when the reaction is performed under aerobic conditions.
  8. 8. The method according to claim 6, wherein the concentration ratio of sodium hypophosphite to pyrite is (13-20) mM (0.1-0.3) g/L when the reaction is carried out under anaerobic or anaerobic conditions.

Description

Method for degrading organic pollutants by utilizing pyrite and sodium hypophosphite in cooperation Technical Field The invention belongs to the technical field of water pollution control and advanced oxidation, and particularly relates to a method for degrading organic pollutants by utilizing pyrite and sodium hypophosphite in a synergistic way. Background Carbamazepine is a typical drug pollutant widely existing in surface water, underground water and effluent of sewage treatment plants, and has limited removal efficiency by the traditional water treatment process (such as adsorption and biodegradation) due to high chemical stability and difficult biodegradation. Therefore, it is important to develop efficient and economical advanced oxidation techniques. Pyrite (FeS 2) is a natural mineral rich in Fe (II) and S 2-, etc. reducing components, and can produce free radical degradation pollutants by activating oxidants. However, pyrite alone has problems of low activation efficiency, high iron leaching, slow reaction rate, and the like. Sodium hypophosphite (NaH 2PO2) is taken as a mild reducing agent, can promote the conversion of Fe (III) to Fe (II) and maintain the free radical chain reaction, but cannot effectively degrade pollutants when used alone. At present, no related report exists on the combined use of pyrite and sodium hypophosphite for degrading organic pollutants. The existing advanced oxidation technology is mostly dependent on external addition of oxidant (such as persulfate, ozone and the like), which not only increases the treatment cost and the process complexity, but also brings potential secondary pollution risks and process uncertainty due to the introduction of strong-oxidization exogenous substances. In addition, the catalytic efficiency and free radical chain reaction of most advanced oxidation processes are severely limited by the participation of dissolved oxygen, so that the catalyst is difficult to effectively operate in typical anoxic environments such as deep groundwater, polluted substrate sludge and the like. Traditional advanced oxidation techniques based on free radicals (e.g., fenton, persulfate activation) rely heavily on dissolved oxygen molecules to participate in the chain reaction, typically with significantly reduced efficiency at dissolved oxygen concentrations below about 2.0 mg/L, and almost failure in a typical sewage or sediment anaerobic environment below about 0.5 mg/L. The present invention aims to provide a method for degrading organic pollutants with high efficiency in an environment where dissolved oxygen is absent or absent. Therefore, the development of the green degradation method based on natural minerals and cheap chemicals, which does not depend on the addition of exogenous oxidants and is not limited by dissolved oxygen, has important research significance and engineering value for promoting the safe and economic application of advanced oxidation technology in the actual water restoration. Disclosure of Invention In order to solve or partially solve the problems existing in the related art, the invention provides a method for degrading organic pollutants by utilizing pyrite and sodium hypophosphite in a synergistic way. The invention provides a method for degrading organic pollutants by utilizing pyrite and sodium hypophosphite in a synergistic way, which comprises the following steps: (1) Ball milling and sieving pyrite, washing sequentially with ethanol and water, and drying to obtain treated pyrite; (2) And (3) under the illumination condition, adding the treated pyrite obtained in the step (1) into the water body containing the organic pollutants to react with sodium hypophosphite, so as to degrade the organic pollutants. In the step (1), the treated pyrite is preserved under anaerobic conditions. In the step (2), the organic pollutants are degraded by stirring reaction at room temperature under the natural light condition. Preferably, in the step (1), the treated pyrite is obtained by drying and then calcining at a temperature of 200 ℃ for 2 hours. Preferably, in the step (2), the ratio of the mass of the hypophosphorous acid substance to the mass of the organic pollutant to the mass of the pyrite is (13-20) mmol (a-10) mg (0.1-0.3) g, and a is not less than 0 <10. The sodium hypophosphite in the reaction system has the addition concentration of 14-20 mM and pyrite in the reaction system of 0.1-0.3-g/L under the aerobic condition, and the sodium hypophosphite in the reaction system has the addition concentration of 13-20 mM and pyrite in the reaction system of 0.1-0.3-g/L under the anaerobic or anaerobic condition. The present invention has found that the presence of molecular oxygen affects the onset threshold and reaction path of pyrite in synergy with sodium hypophosphite. Under the aerobic condition, the concentration ratio of sodium hypophosphite to pyrite is (14-20) mM (0.1-0.3) g/L, so that the degradation reaction can be effectively star