A kind of photocatalyst of nitrogen-modified perovskite composite molecular sieve and its preparation method and application method

Abstract

The invention discloses a photocatalyst of a nitrogen-modified perovskite composite molecular sieve, a preparation method and an application method thereof, wherein the photocatalyst is N-LaFeO 3 @MCM‑41, the preparation method of the photocatalyst is to weigh lanthanum nitrate, ferric nitrate, urea, MCM‑41 in a molar ratio of 1:1:1‑3:3‑7, add water to dissolve, stir to form A liquid; The mixture is dissolved in water and stirred to form liquid B, wherein the molar ratio of the complexing agent to lanthanum nitrate is 1-4:1; the liquid B is slowly added to liquid A to polymerize into a sol, dried and calcined to obtain a photocatalyst , and provide an application method of the photocatalyst for treating aromatic compound organic wastewater. The photocatalyst of the invention can efficiently degrade aromatic compound organic waste water, and the preparation method is convenient to operate and low in cost. It is applied to the aromatic compound organic waste water without secondary pollution, and is energy-saving and environment-friendly.

Description

technical field [0001] The invention relates to a photocatalyst, a preparation method and an application method thereof, in particular to a photocatalyst of a nitrogen-modified perovskite composite molecular sieve, a preparation method and an application method thereof. Background technique [0002] Aromatic compounds are a class of compounds with a benzene ring structure. They are stable in structure, difficult to decompose, and highly toxic. Aromatic compounds come from lignin and secondary metabolic processes of higher plants on the one hand, and various chemical products synthesized in industry on the other hand, such as pesticides, herbicides, dyes, explosives, etc. Aromatic compounds such as benzene, benzonitriles and phenols are being manufactured in millions of tons per year. These compounds are widely used in fuels and industrial solvents, and they are used in the production of pharmaceuticals together with polycyclic aromatic compounds and chlorinated biphenyls. ,...

AI Technical Summary

Problems solved by technology

Although the biodegradation method has a mature treatment process and low cost, it is only suitable for the treatment of low-concentration aromatic compounds; chemical oxidation and advanced oxidation technology methods refer to adding a certain amount of oxidants (oxygen, hydrogen peroxide, Ozone, etc.), under certain conditions, a strong oxidizing agent is produced, so that the aromatic compound is oxidized and degraded, and finally completely mineralized into carbon dioxide and water

Although this method has a good treatment effect, it is difficult to recover the oxidant and the operation cost is expensive, which affects its use; the adsorption method is a more effective method for the treatment of aromatic compounds, mainly using porous materials to adsorb pollutants in wastewater, wastewater The pollutants in the adsorbent will enter the interior of the adsorbent through the pore structure of the adsorbent, and then the adsorbent can be treated to a certain extent, so that the adsorbent can be recycled

However, the equipment investment is large, the reusability of the adsorbent is low and the regeneration problem needs to be solved; the cold plasma treatment wastewater technology is a new wastewater treatment technology that combines high-energy electron radiation, ozone oxidation and ultraviolet photolysis. , but this method consumes a lot of energy; nano photocatalysis technology has mild reaction conditions, can use ultraviolet light and sunlight and other conditions, directly and indirectly convert pollutants into CO2, water and other harmless substances, consumes little energy and does not produce Secondary pollution

Commonly used photocatalysts such as TiO2 have disadvantages such as wide band gap, inability to make full use of visible light, and low quantum efficiency, while perovskite catalysts have narrow band gap and small band gap, which is a good photocatalyst, but calcium Titanium has the problem of high electron-hole recombination rate, and it does not respond well to a wide range of visible light.

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