CN-117504941-B - With bimetallic UiO-66-NH2MOF photocatalyst for supporting Pt

Abstract

The invention discloses a MOF photocatalyst taking bimetallic UiO-66-NH 2 as a carrier to load Pt, which is prepared by modifying the carrier by a solvothermal method and then loading Pt by a sodium borohydride reduction method. The Pt@UiO-66-NH 2 (Zr: ce=2:1) photocatalyst obtained by the method has high degradation rate, high mineralization rate and high stability in the process of degrading toluene by photocatalysis, and the preparation method is simple and easy to implement, and has good application prospect in the terminal treatment process of oxidative degradation of photocatalytic VOCs.

Inventors

• DAI WENXIN
• Luo Songyu
• FU XIANZHI
• CHEN XUN
• ZHANG ZIZHONG

Assignees

• 福州大学
• 清源创新实验室

Dates

Publication Date

20260508

Application Date

20231116

Claims (1)

1. 1. The application of the MOF photocatalyst taking bimetal UiO-66-NH 2 as a carrier to Pt in VOCs degradation is characterized in that the MOF photocatalyst taking bimetal UiO-66-NH 2 as the carrier to Pt is applied to a terminal treatment system for photocatalytic or ultraviolet photocatalytic oxidative degradation of VOCs under ultraviolet visible light, the degradation temperature is 170 ℃, the photocatalyst is a high-dispersion catalyst taking bimetal MOF material UiO-66-NH 2 as a carrier and Pt as a cocatalyst for modification, the content of Pt in the photocatalyst accounts for 1.0 wt percent of the total catalyst, and the molar ratio Zr of metal centers in the UiO-66-NH 2 carrier is Ce=2:1; The preparation method of the MOF photocatalyst taking the bimetal UiO-66-NH 2 as the carrier to load Pt specifically comprises the following steps: (1) The UiO-66-NH 2 sample is synthesized by a solvothermal method, namely zirconium chloride, cerium chloride and 2-amino terephthalic acid are firstly added into DMF under intense magnetic stirring, glacial acetic acid is continuously added dropwise, wherein the volume ratio of the DMF to the glacial acetic acid is 10:1, then the mixture is subjected to ultrasonic treatment for 30min until a clear solution is obtained, the clear solution is transferred into a Teflon lining, the reaction is carried out for 24h at a temperature of 120 ℃, the reaction is carried out by a baking oven, the reaction is carried out after cooling, centrifugal filtration is carried out, and the obtained yellow solid is dried in vacuum for 12h, thus obtaining a UiO-66-NH 2 carrier; (2) Activating the UiO-66-NH 2 carrier obtained in the step (1) for 3 hours at 150 ℃, cooling, adding anhydrous n-hexane, carrying out ultrasonic treatment for 1 hour to form a uniform suspension, dropwise adding a sodium chloroplatinate solution, continuously stirring for 3h, adding ethanol for cleaning, centrifuging, vacuum drying the obtained solid at 60 ℃ for 12 hours, then adding a NaBH 4 solution, continuously stirring for 15 min, centrifuging, washing with deionized water to obtain a precipitate, and vacuum drying at 80 ℃ to obtain the MOF photocatalyst with the bimetallic UiO-66-NH 2 as a carrier for loading Pt; The DMF consumption in the step (1) is 60 mL, the glacial acetic acid consumption is 6mL, and the zirconium chloride and cerium chloride consumption are respectively 0.18g and 0.12g; The concentration of the sodium chloroplatinate solution in the step (2) was 4.2 mg.mL -1 , and the addition amount thereof was 0.48 mL per 200mg of UiO-66-NH 2 carrier.

Description

MOF photocatalyst with bimetallic UiO-66-NH 2 as carrier for loading Pt Technical Field The invention belongs to the field of atmosphere treatment, the field of organic emission of VOCs waste gas treatment and the field of non-organic emission of VOCs waste gas treatment, and particularly relates to a MOF photocatalyst taking bimetal UiO-66-NH 2 as a carrier to load Pt, a preparation method and application thereof. Background In recent years, the rapid growth of the global population and the rapid development of industry have led to energy crisis and environmental pollution, severely affecting human health and sustainable development of the environment. Environmental protection and contaminant degradation techniques are therefore the most important topics. Among them, volatile Organic Compounds (VOCs) have been the focus of attention of researchers at home and abroad as important precursors for secondary pollutants such as photochemical smog, fine particulate matter (PM 2.5) and ozone (O 3). Wherein part of VOCs are ozone precursor substances, can enhance greenhouse effect, has irritation and toxicity to human body, can irritate eyes and respiratory tract, damage central nerve, damage liver, kidney, brain and nervous system, and further has carcinogenicity, teratogenic effect and reproductive system toxicity. Besides the original treatment of VOCs, the tail gas treatment technology is also enhanced, and common tail gas treatment technologies comprise adsorption technology, combustion technology, photocatalysis technology and biocatalysis technology. The adsorbent in the adsorption technology needs to be replaced and regenerated regularly and VOCs cannot be decomposed thoroughly, the combustion technology needs to consume a large amount of fuel, the risk of secondary pollution exists, the requirements of the biocatalysis technology on environmental conditions such as temperature, humidity and the like are high, the operation is complex, and the treatment effect is influenced by the activity of microorganisms. Obvious advantages of the photocatalytic technology include efficient degradation of VOCs, no secondary pollution, simple operation, compact equipment, no need for additional energy consumption, and broad spectrum. These advantages make the photocatalytic technology one of the technologies of great interest and application in the field of VOCs abatement treatment. Metal-organic frameworks (Metal-Organic Frameworks, MOFs) as a novel class of porous materials with high specific surface area, adjustable pore size and chemical composition, and abundant functional modification sites have been widely studied and applied to adsorption and catalytic degradation of VOCs. Currently, MOFs have been studied mainly for degradation of VOCs in several ways: MOFs have high specific surface area and adjustable pore diameter, and the adsorption performance can be optimized by adjusting the structure and the composition of the MOFs, so that the adsorption capacity and the selectivity of the MOFs on VOCs are improved. For example, the affinity and adsorption capacity of MOFs for specific VOCs can be enhanced by introducing different functional groups or metal ions. Several studies have reported the adsorption properties of various VOCs by different MOFs. For example, MOFs such as UiO-66 and MIL-101 have good adsorption capacity for VOCs such as benzene, toluene and xylene. MOFs can be used as a catalyst carrier to load active components on pore channels or surfaces of the MOFs, so that the catalytic degradation of VOCs is realized. The activity and stability of the catalyst can be regulated and controlled by regulating the structure and composition of MOFs, and the catalytic degradation efficiency is improved. For example, the introduction of metal ions or functional groups can enhance the catalytic activity and selectivity of MOFs. Disclosure of Invention Aiming at the problems of low degradation rate, low mineralization rate and low stability in the existing photocatalytic oxidative degradation application of VOCs, the invention provides a preparation method and application of the MOF photocatalyst taking bimetallic UiO-66-NH 2 as a carrier to load Pt. In order to achieve the above purpose, the invention adopts the following technical scheme: And a certain amount of Ce is introduced into a basic carrier UiO-66-NH 2 (Zr) to generate UiO-66-NH 2 (Zr: ce=2:1, molar ratio), and the Ce is introduced into a metal oxygen cluster to improve the visible light absorption and the photoresponse of the catalyst, reduce the impedance and promote the carrier separation, so that the activity is improved, and the catalytic degradation efficiency is improved. Pt is used as a catalyst promoter to be compounded with a carrier, so that the visible light absorption and the light response of the catalyst can be further improved, the impedance is reduced, and the carrier separation is promoted. As described above, the photocatalyst uses a 300W