CN-121972226-A - Functional material based on graphite carbon nitride loaded Bi-MOF, preparation method and application

Abstract

The invention discloses a graphite carbon nitride loaded Bi-MOF-based functional material, a preparation method and application thereof, wherein the graphite carbon nitride loaded Bi-MOF-based functional material is a bismuth-based metal organic framework material composite graphite carbon nitride-based composite material, and is used for treating Cr (VI) in water environment. The Bi-MOF/g-C 3 N 4 composite material is prepared by an in-situ compounding method, has high-efficiency photocatalytic reduction capability on Cr (VI) in water, and can reduce more than 99% of Cr (VI) within 3 hours. The composite material and the treatment process thereof developed by the invention have certain application value in the field of high-valence heavy metal treatment, and provide a feasible scheme for treating heavy metal pollutants in environment with green low carbon.

Inventors

• SUN JIMEI
• ZHANG WEN
• ZHOU HONGBI
• LI WENFENG
• LI KANGJIAN
• WANG FANG
• Hui Xiaojuan
• Lv Chongliang
• MA GUOLIANG

Assignees

• 中国化学工程第十一建设有限公司
• 河南康泰科技有限公司
• 河南省安全生产和职业健康协会

Dates

Publication Date

20260505

Application Date

20260127

Claims (10)

1. 1. The functional material based on the graphite carbon nitride loaded Bi-MOF is characterized in that the functional material is in a powder shape, and the Bi-MOF with a hexagonal prism structure is loaded on the graphite carbon nitride.
2. 2. The functional material based on the graphite carbon nitride supported Bi-MOF of claim 1, wherein the Bi-MOF grows on the graphite carbon nitride in situ, and a heterojunction structure is formed at the interface of the Bi-MOF and the graphite carbon nitride, so that the photocatalytic performance of the material is improved.
3. 3. The method for preparing a functional material based on graphite carbon nitride supported Bi-MOF according to claim 1 or 2, comprising the steps of: (1) The preparation of the protonated g-C 3 N 4 comprises the steps of weighing massive graphite carbon nitride, adding concentrated nitric acid, stirring and dispersing uniformly, adding distilled water, stirring at room temperature, transferring into a reaction kettle for reaction, cooling to room temperature, centrifugally washing and separating, and drying and grinding to obtain sample powder, namely the protonated g-C 3 N 4 ; (2) The preparation of Bi-MOF/g-C 3 N 4 comprises dispersing protonated g-C 3 N 4 in N, N-dimethylformamide solution containing Bi (NO 3 ) 3 ·5H 2 O and benzene-1, 3, 5-tri (m-benzoic acid), performing ultrasonic treatment, placing into a reaction kettle for reaction after uniform dispersion, centrifuging after reaction, separating to obtain a product, washing with methanol, and drying to obtain the functional material Bi-MOF/g-C 3 N 4 loaded with Bi-MOF by graphite carbon nitride.
4. 4. The method for preparing a functional material based on a Bi-MOF supported on graphite-carbon nitride according to claim 3, wherein the reaction temperature in the step (1) is 140-160 ℃, the reaction time is 1-3 hours, and the dosage ratio of graphite-carbon nitride, concentrated nitric acid and distilled water is (0.5-1.0) g (20-30) mL (75-150) mL.
5. 5. The method for preparing a functional material based on Bi-MOF supported on graphite carbon nitride according to claim 3, wherein in the step (2), the molar ratio of Bi (NO 3 ) 3 ·5H 2 O to benzene-1, 3, 5-tris (m-benzoic acid) is 1:10-1:13, and the amount of protonated g-C 3 N 4 added is 0.75-1.5 times the sum of Bi (NO 3 ) 3 ·5H 2 O and benzene-1, 3, 5-tris (m-benzoic acid) mass.
6. 6. The method for preparing a functional material based on Bi-MOF supported on graphite carbon nitride according to claim 3, wherein in the step (2), the reaction temperature is 120-180 ℃ and the reaction time is 10-14 h.
7. 7. Use of the graphite carbon nitride supported Bi-MOF based functional material according to claim 1 or 2 in photocatalytic reduction of heavy metal chromium contaminants.
8. 8. The method according to claim 7, wherein the protonated g-C 3 N 4 loaded Bi-MOF functional material Bi-MOF/g-C 3 N 4 , potassium dichromate and formic acid are added into a photochemical reaction bottle, distilled water is used for constant volume, the photochemical reaction bottle is placed in a multi-channel photocatalytic reaction system, when the solution reaches adsorption-desorption equilibrium, the photocatalytic reduction experiment is carried out under illumination, 5 mL solutions are sucked from the reaction system every 30min, centrifugation is carried out, the supernatant is taken, and the absorbance value of the solution is measured.
9. 9. The use according to claim 8, wherein the protonated g-C 3 N 4 -loaded Bi-MOF is used in an amount of 4 mg, the potassium dichromate is used in an amount of 0.01 mmol, the formic acid is used in an amount of 0.7 mL, distilled water is used to reach a volume of 10mL, the concentration of the hexavalent chromium solution obtained is 2 mM, the catalytic reduction experimental temperature is 60 ℃, the catalytic process is tested in a multifunctional photochemical reactor, and the light source used in the whole process of photocatalytic reduction of the hexavalent chromium solution is 5W LED.
10. 10. The method according to claim 9, wherein the protonated g-C 3 N 4 -loaded Bi-MOF functional material has a reduction efficiency of more than 99% on hexavalent chromium ions within 3 hours.

Description

Functional material based on graphite carbon nitride loaded Bi-MOF, preparation method and application Technical Field The invention relates to the technical development field of green low-carbon treatment of heavy metal pollutants, in particular to a Bi-MOF functional material, a preparation method and application. Background Chromium (Cr) is one of the important industrial materials and has applications in tanning, electroplating, metal finishing, magnetic tape, pigments, electrical or electronic equipment, catalysis, etc. It enters the environmental system (air, water, soil, etc.) mainly through human activities such as extraction and exploitation of ores, pesticide spraying, paper industry, leather manufacture, application of chemical fertilizers, and solid waste treatment including sewage sludge and automobile exhaust. Chromium removal is of increasing concern due to its environmental hazards and accumulation in the food chain. Chromium (Cr) exists in many valence states (from-2 to +6) in nature, mainly in the steady state of trivalent chromium (Cr (III)) and hexavalent chromium (Cr (VI)). They exhibit distinct chemical properties and affect organisms in different ways. Cr (VI) has higher toxicity and flowability than Cr (III). Chromium (VI) has been listed as a high priority hazardous contaminant due to its carcinogenic, mutagenic and teratogenic effects on organisms. Therefore, it is important to develop a cost effective and reliable technique to remove Cr (VI) before the industrial wastewater is discharged to the aquatic system. At present, the treatment modes for chromium pollution can be classified into two types, namely, directly absorbing chromium in wastewater and soil and reducing Cr (VI) with relatively high toxicity into Cr (III) with relatively low toxicity. The specific solving means mainly comprise adsorption method, membrane filtration method, electrochemical method, physicochemical method, biological removal method and the like. Among them, photocatalysis has been a technology for recent decades, which has great potential in treating environmental pollution and solving energy crisis, and attracts the eyes of many scientific researchers. After the photocatalyst is excited by light, electrons and holes are generated in a conduction band and a valence band respectively, the electrons are equivalent to a reducing agent, the holes are equivalent to an oxidizing agent, and the electrons react with different substances on the surface of the catalyst in the photocatalytic process, so that the efficient and green photocatalytic application process is realized. For example, AHMED SHAWKY adopts a solution method to prepare a Bi 2S3 sensitized TiO 2 nano structure for high-efficiency photo-reduction of hexavalent chromium ions in visible light sewage. The Metal-organic framework material (Metal-Organic Frameworks, MOFs) is focused by people by virtue of the advantages of large specific surface area, ordered and adjustable gaps, multiple functions, mild synthesis conditions and the like, and is widely applied to various aspects such as photocatalytic degradation of dyes, hydrogen production, CO 2 reduction, degradation of heavy Metal ions and the like. Among them, bismuth-based MOFs have the advantages of various structures, high stability, simple preparation and the like, and are widely studied. For example, ye et al synthesized a novel Bi-MOF complex using hydrothermal method and utilized it to photo-catalytically degrade methyl orange. CN 116673070A discloses a preparation method and application of a novel compound semiconductor photocatalyst, and the prepared novel compound semiconductor photocatalyst g-C 3N4/Bi-MOF synthesizes monomethyl fumarate under the light induction. Disclosure of Invention In order to realize effective degradation of Cr (VI) in the environment and reduce the harm to the environment, the invention provides a functional material based on protonated graphite carbon nitride g-C 3N4 loaded with Bi-MOF, a preparation method and a photocatalysis treatment process of heavy metal chromium in water environment. The invention loads bismuth-based metal organic framework materials with protonated graphite carbon nitride, and develops a photocatalysis treatment process for hexavalent chromium-containing sewage. The composite material and the treatment process thereof have wide application value in the field of chromium-containing sewage. In order to solve the technical problems, the invention adopts the following technical scheme: Bi (NO 3)3·5H2 O is used as a metal source, benzene-1, 3, 5-tri (m-benzoic acid) is used as an organic ligand, the Bi-MOF/g-C 3N4 is obtained by compounding the Bi (NO 3)3·5H2 O) with protonated graphite carbon nitride, and the Bi-MOF/g-C 3N4 is used as a photocatalyst for treating heavy metal chromium ions in sewage so as to achieve the aim of reducing environmental pollution. The invention also provides a composite material based on protonated graphite car