CN-118420079-B - Method for rapidly treating DEP in wastewater

Abstract

The invention provides a method for rapidly treating DEP in polluted water. The method comprises the steps of a, placing a proper amount of Tetrahydrofuran (THF) in a beaker with proper capacity, wherein the volume of the beaker is not easy to exceed three times of that of the tetrahydrofuran, b, adding a proper amount of PVC resin into the beaker according to a proper proportion, c, sealing the obtained homogeneous solution, placing the solution in pure water for ultrasonic treatment for 10-15min, taking out the solution after the solution is clarified, d, adding the obtained high-efficiency removing solution into DEP polluted water, taking out the treated suspended matters, and finishing the water treatment process after the THF volatilizes. Compared with the scheme that organic pollutants such as DEP in water are removed by directly using PVC resin, the method has the advantages that the removal efficiency is greatly increased, the time for pollution treatment is saved, and the treated pollutants are easier to remove.

Inventors

• WU PINGXIAO
• LIU JIEYU
• WU JIAYAN
• Sun Leiye
• LI BO
• HUANG MINYE
• ZHU NENGWU
• DANG ZHI

Assignees

• 华南理工大学

Dates

Publication Date

20260505

Application Date

20240515

Claims (7)

1. 1. A method for rapidly treating DEP in wastewater, comprising the steps of: (1) Preparing PTFR under ultrasonic resonance condition after fusing PVC and THF solution, wherein the PTFR fusion method is to add PVC powder into THF solution stirred at high speed, wherein the concentration of the PVC in the PTFR is 10-120mg/L, the rate of adding PVC into the THF solution in the fusion process is 100-500mg/min, the stirring time is 5-10min, and the ultrasonic resonance time is 5-15min; (2) Adding the PTFR obtained in the step (1) into DEP wastewater, rapidly stirring, and taking out plasticization; (3) And (3) placing the liquid obtained in the step (2) in a fume hood, and finishing the pollution treatment process after the THF solution volatilizes.
2. 2. The method for rapid treatment of DEP in wastewater according to claim 1, wherein in step (1), the PVC is a powdery granular solid having a particle size of 20-80 mesh.
3. 3. The method for rapid treatment of DEP in wastewater according to claim 1, wherein in step (1), the THF is of HPLC grade of 99.9% or more.
4. 4. A method for rapid treatment of DEP in wastewater according to claim 1, wherein in step (2) the volume added to the DEP wastewater is 2-10%.
5. 5. The method for rapidly treating DEP in wastewater according to claim 1, wherein in the step (2), the plasticization is taken out within 1 min.
6. 6. A method for rapid treatment of DEP in wastewater according to claim 1, wherein in step (3) the holding time in the fume hood is 8-48 hours.
7. 7. A PTFR for treating wastewater produced by the method of any one of claims 1-6.

Description

Method for rapidly treating DEP in wastewater Technical Field The invention belongs to the technical field of polluted water treatment, and particularly relates to a method for instantaneously treating DEP in wastewater. Background Plastics are materials formed by chemical synthesis of polymers, and various plastic products derived from the same are increasingly used in human life, and among them, polyvinyl chloride (PVC) plastic products are widely used, such as plastic bottles, billboards, gloves, and the like. Polyvinyl chloride plastics are high polymers synthesized from PVC monomers by industrial processes such as distillation, polymerization, stripping, drying and the like. Because of the high chlorine content of PVC plastics, their recycling of waste materials and additives is challenging. Different performance requirements are applied to plastisol in the production of vinyl floors, carpets, physical examination gloves, stickers, automobiles, packaging and the like. Each component entering the pulp alcohol or organic alcohol may have a direct or indirect effect. Wherein the neutralizing plasticizer is two main components. PVC is a specialty resin that differs not only from other manufacturing processes, but also in the form of use and manufacturing application. Compared with the suspension grade GP, the particle size is larger, and the dispersion is better. Polyvinyl chloride plastics are the third thermoplastic synthetic plastics in world production, and PVC in the environment contains a variety of additive components, and various types of additives are added during production to improve extrusion resistance and extend the service life of the polymer, and these additive monomers are encapsulated between polymer matrices, but are not chemically bound to the polymer, so that the plastics may interact with organic contaminants in the environment under physical action. The research shows that PVC has the second adsorption capacity in common microplastic in four environments and can be used as a carrier of zinc, copper and other heavy metals, so that PVC is indispensable to the research on the adsorption of pollutants in the environment. There are studies on the fact that additives are compounds which have to be added to polymers (synthesis) during the processing of plastic molding, since polymer monomers are more easily combined with additives, the adsorption of additives by plastic polymer monomers and the fixation mechanism of additives during plasticizing are worth intensive studies. In the production and processing of plastic articles, it is often necessary to add certain compounds, collectively referred to as additives, in certain formulation ratios to improve the performance and extend the useful life of the polymer. Flexible polyvinyl chloride products, such as packaging/greenhouse films, toys, medical tubing, wires, cables, and flooring materials, may contain significant amounts of phthalate salts. Phthalate plasticizers are endocrine disruptors that can have adverse developmental and reproductive effects on humans and animals. A large amount of plastic garbage finally enters the ocean environment, and the release of the additive is often accompanied in the natural aging and decomposition process of the plastic garbage. Various compounds currently used as additives for plastics are detected in all large estuaries and sea water worldwide, with the highest detection frequency of diethyl phthalate. Phthalate is the main synthetic component of polyvinyl chloride plastics, and has the main functions of weakening secondary bonds among molecules, increasing the mobility of molecular bonds and the plasticity of the molecules, reducing the crystallinity of the molecules and enabling the plastics to have more flexibility. The existing technology for removing phthalate esters in water mainly comprises adsorption, membrane separation, biodegradation and photocatalysis. The problems of low reaction rate, difficult recovery and treatment of the adsorption material, possible secondary pollution and the like limit the wide application of most technologies. Adsorption technology is the most widely used technology, and sequencing batch adsorption technology is used to efficiently remove pollutants in water during actual sewage treatment. However, most of the adsorption materials used in the adsorption technology consume long time, the manufacturing process is complex, and the research on rapid adsorption to remove phthalate esters in water is very little. DEP is the most representative of phthalates and is present in excess of 60% of polyvinyl chloride plastic additives. The removal of DEP in the environment is critical to the healthy development of humans and organisms. DEP bonds to plastics mainly by weak van der waals forces and hydrogen bonding. Little research has been done on the binding effect and mechanism of plastics on DEP. According to the experiment, DEP in the water body is used as a target pollutant