Preparation method and application method of Ag/AgBr-diatomite composite photocatalyst

Abstract

The invention discloses a preparation method and an application method of an Ag / AgBr-diatomite composite photocatalyst. The preparation method comprises the following steps: (1), performing mixed acidpickling by using hydrochloric acid with the concentration of 20% and diatomite, washing with distilled water, drying in a drying oven, and calcining in a muffle furnace; (2), dissolving the diatomite pretreated in the step (1) in the distilled water, stirring, adding AgNO3, stirring, dropwise adding a KI solution into a mixed solution, stirring for 4 hours in the dark after addition, washing, and drying to obtain an AgBr-diatomite composite photocatalyst; (3), flatly spreading the AgBr-diatomite composite photocatalyst treated in the step (2) on watch glass, and irradiating for 1 hour. A loaded photocatalyst is used for degrading organic contaminants in a water body, and the application method comprises the following specific steps: (1), placing the loaded photocatalyst into the organiccontaminant containing water body; (2), uniformly mixing the organic contaminant containing water body and the composite catalyst for 30 minutes in a photocatalytic reactor.

Description

technical field [0001] The invention relates to a preparation method and an application method of an Ag / AgBr-diatomite composite photocatalyst, belonging to the technical field of environmental protection. Background technique [0002] With the expansion of the scope of human production activities, more and more serious environmental pollution problems have emerged, especially the pollution of organic matter to the water environment is very serious, which has attracted more and more people's attention in recent years. Most of these water organic substances are poisonous to the human body, and some of them can induce various serious diseases, have carcinogenic or teratogenic effects, and can also photochemically react with nitrogen oxides in the atmosphere to destroy the atmospheric ozone layer. Therefore, the control of water organic pollution has become the research focus of scientists in the future. [0003] In recent years, photocatalytic oxidation technology has attract...

AI Technical Summary

Problems solved by technology

However, there are still some problems in practical application of this technology to be further solved.

First of all, the light source utilization rate is low and photocatalyst recovery is difficult. Most of the photocatalysts used in the treatment of organic pollutants in photocatalytic oxidation technology are powders, which may cause waste of catalysts in the process of atmospheric treatment, and in the reaction process , only a small amount of photocatalyst on the surface absorbs ultraviolet light and acts as a photocatalyst, resulting in low photon quantum efficiency. At the same time, the powder photocatalyst is easily lost during the reaction process, which is not conducive to the reuse of photocatalyst.

Secondly, the efficiency of gas-solid phase photocatalysis is easily affected by the actual atmospheric environmental factors.

Photocatalytic technology is greatly affected by the concentration level of pollutants, relative humidity, and oxygen concentration. Especially in industrial applications, the environmental application conditions are more complex, which often leads to low photocatalytic efficiency.

Finally, the long-term activity stability of the photocatalyst is poor, and the surface of the photocatalyst is prone to deposit difficult-to-degrade intermediates during the process of photocatalytic degradation of organic matter, thereby blocking the contact between the catalyst and ultraviolet light, resulting in a decrease in the catalytic activity of the photocatalyst and in-situ regeneration. , which greatly affects the industrial application of photocatalytic oxidation technology