Device and method for photoacoustic synergistic degradation of perfluorooctane sulfonate

Abstract

The invention discloses an optoacoustic synergic perfluorooctane sulfonate (PFOS) degradation device and method. The device comprises an ultrasonic generator and a water tank which is arranged on the ultrasonic generator and used for keeping reaction temperature, wherein a reactor for containing wastewater containing potassium perfluorooctane sulfonate is arranged in the water tank; an ultraviolet lamp is arranged above the reactor; and the reactor is made from an inert material. The method comprises the following steps: a) adding the wastewater containing PFOS to be treated into the reactor, adding heteropoly acid as a catalyst, and adding H2O2 to control the pH value at 2-4; and b) turning on the ultraviolet lamp and ultrasonic generator, reacting under the ultrasonic power of 100W for 3-5 hours, and discharging. The device is simple in structure; and the UV-US / H3PW12O40 optoacoustic synergic catalytic oxidation system fully displays the strong decomposition effect of the 358 kHz ultrasonic and the photocatalysis action of the heteropoly acid under the 254nm ultraviolet irradiation, thereby implementing effective degradation and defluorination of the PFOS.

Description

technical field [0001] The invention belongs to the technical field of environmental engineering water treatment, and relates to a treatment device and method for perfluorinated compounds such as persistent organic pollutants perfluorooctane sulfonate (PFOS) in water bodies, specifically a UV-US / H 3 PW 12 o 40 A device and method for synergistic catalytic oxidation degradation of perfluorooctane sulfonate (PFOS) in water by a system. Background technique [0002] Perfluorinated compounds (PFCs) are widely used in industrial and civil fields such as textiles, papermaking, packaging, pesticides, carpets, leather, polished floors, shampoos and fire-fighting foams. The PFCs that exist in the environment mainly include perfluorocarboxylic acids, perfluorosulfonic acids, perfluoroamides and perfluorotelomer alcohols, etc., and perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are currently used The most widely used perfluorinated organic substances, PFOS is mor...

AI Technical Summary

Problems solved by technology

[0003] The C-F bond of PFOS leads to its very stable chemical properties. So far, no evidence and related reports of their degradation in vivo have been found, nor have any studies on their natural degradation been found.

Conventional advanced oxidation techniques (such as O 3 , O 3 / UV,O 3 / H 2 o 2 and H 2 o 2 / Fe 2+ ) cannot effectively degrade the

At present, although many researchers have carried out research on the removal and recovery of different perfluorinated compounds by means of biodegradation, redox, high-temperature incineration, etc., they all have low degradation efficiency, slow rate, and high energy consumption to varying degrees. , complex operation, low recovery rate, secondary pollution and other disadvantages

Therefore, the current research on the degradation and restoration of PFCs is still in its infancy, and only a few studies are in progress, such as subcritical systems and photocatalytic systems, which have better degradation effects, but require high conditions and consume a lot of energy; The conditions are relatively mild, but the defluorination process is slow and the efficiency is not high; the photooxidation system is difficult to use in the actual wastewater treatment due to the use of a large amount of oxidant, which will cause secondary pollution and high costs.

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