Method for producing hydroxyl radicals and removing organic pollutants in water by using organic membrane

Abstract

The invention provides a method for using an organic film to generate hydroxyl radicals and remove organic pollutants in water. The method of the present invention adopts nitrocellulose membrane as the photocatalytic material, puts the nitrocellulose membrane in water, and uses the sun or a solar lamp with a wavelength greater than 280nm as the light source to illuminate the nitrocellulose membrane, so that the surface of the nitrocellulose membrane undergoes a photochemical reaction to generate free hydroxyl groups. The generation rate of hydroxyl radicals can be adjusted by adjusting the membrane surface area and light intensity. The produced hydroxyl radicals can well remove typical organic pollutants such as phenol, bisphenol A and thiamphenicol in water. This method of generating hydroxyl radicals is simple, economical, and efficient, and does not require any precursors of hydroxyl radicals to be introduced into the aqueous solution. Hydroxyl radicals are generated on the surface of the solid-phase membrane without secondary pollution, and can be applied to wastewater processing and other fields.

Description

technical field [0001] The invention belongs to the field of photochemical technology and sewage treatment, and in particular relates to a method for using an organic film to generate hydroxyl radicals and remove organic pollutants in water. Background technique [0002] Hydroxyl radical (·OH) is a kind of active oxygen radical, which has strong oxidizing property, and its oxidation-reduction potential is 2.80V, second only to fluorine atom, and can interact with most inorganic or organic substances at a diffusion-controlled rate For the reaction, the reaction rate constant is generally greater than 10 8 mol L -1 the s -1 . In the field of environmental science, hydroxyl radicals are used for the degradation of organic pollutants, and are the most important active intermediates in the advanced oxidation process wastewater treatment process. [0003] There are many ways to generate hydroxyl radicals, which can be roughly divided into chemical catalysis, ozone / hydrogen per...

AI Technical Summary

Problems solved by technology

The chemical catalytic method generally adopts the Fenton reaction, and uses iron ions to catalyze the decomposition of hydrogen peroxide to generate hydroxyl radicals. This method is simple, easy and relatively cheap, but it will produce a large amount of iron-containing sludge when it is applied on a large scale, which will bring about no change to the subsequent treatment; Ozone and hydrogen peroxide undergo photolysis under the action of ultraviolet light to produce hydroxyl radicals, but the precursors of hydroxyl radicals, ozone and hydrogen peroxide, need to be added, and there are many side reactions; semiconductor titanium dioxide particles are used as catalysts to photocatalyze hydroxyl radicals. It is necessary to ensure that the catalyst is in a suspended state, and photocatalysis also needs to separate the photocatalyst, which has poor continuous operability, and dissolved oxygen has a great influence on the generation of hydroxyl radicals by photocatalysis of titanium dioxide; And its catalytic components have high requirements, and the current efficiency is low; the ray method has the problems of high cost and great harm to human body

[0004] Therefore, several methods for producing hydroxyl radicals that are commonly used at present either have more side reactions, or have poor operability and low efficiency, or have greater harm to the environment or the human body. Therefore, the existing methods for producing hydroxyl radicals are all There are their own problems, it is difficult to popularize and apply

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