COMPOSITE WITH SYNERGISTIC EFFECT OF ADSORPTION AND VISIBLE LIGHT CATALYTIC DEGRADATION AND PREPARATION METHOD AND APPLICATION THEREOF

Abstract

The invention discloses a composite with an adsorption-visible light catalytic degradation synergistic effect and a preparation method and application thereof. The preparation method includes the specific steps that firstly, a bismuth oxyiodide/bismuth oxychloride composite nano-particle loaded activated carbon fiber composite ACF@BiOI.sub.xCl.sub.1-x is synthesized; then, the fiber surface is grafted with polyethyleneimine, and the end composite PEI-g-ACF@BiOI.sub.xCl.sub.1-x is obtained. The composite can rapidly adsorb pollutants in water, and meanwhile the pollutants are efficiently degraded with a photocatalyst loaded on the surface of the composite; besides, the purpose of recycling and reusing the photocatalyst is achieved, the comprehensive treatment capability of the composite is improved, the service life of the composite is prolonged, and the use cost is lowered.

Claims

1. A preparation method of a composite with synergistic effect of adsorption and visible light catalytic degradation, which comprises the steps as below: 1) preparation of activated carbon fibers with bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized on: dissolving bismuth nitrate pentahydrate and activated carbon fiber in solvent to obtain solution A; dissolving potassium iodide and potassium chloride in solvent to obtain solution B; adding solution B to solution A under stirring, mixing evenly, then moving the reaction mixture to a hydrothermal reactor and reacting for 10 to 16 hours at 120 to 180° C., after the completion of the reaction, the reaction vessel is taken out, cooled and opened, and the fibrous product is collected by filtration, washed and dried to obtain bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite; wherein, the molar ratio of bismuth nitrate pentahydrate, potassium iodide and potassium chloride is 1:x:(1−x), and 0<x<1; the ratio of bismuth nitrate pentahydrate and activated carbon fiber is 1 mol: 25˜50 g; 2) the graft of polyethyleneimine: dispersing the bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite obtained in step 1) in solvent, adding silane coupling agent, reacting for 4 to 8 hours at 60 to 80° C. while stirring, then adding polyethyleneimine solution, continue stirring to react for 4 to 6 hours, after the reaction, the mixture is cooled and filtered to collect the fibrous product, washed and dried to obtain a composite material with synergistic effect of adsorption and visible light catalytic degradation; wherein, the ratio of said bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite, silane coupling agent and polyethyleneimine solution is 50 mg:50 μL:1˜10 g.

2. The preparation method according to claim 1, wherein: in step 1), said solvent is either of water, ethyl alcohol, ethylene glycol, glycerol or any mixture thereof.

3. The preparation method according to claim 1, wherein: in step 2), said solvent is either of acetonitrile, N,N-Dimethylformamide, N,N-Dimethylethanolamine or any mixture thereof.

4. The preparation method according to claim 1, wherein: in step 2), said silane coupling agent is (3-bromopropyl) trimethoxysilane or (3-chloropropyl) trimethoxysilane.

5. The preparation method according to claim 1, wherein: in step 2), the mass concentration of said polyethyleneimine solution is 10%, wherein the M.sub.w of polyethyleneimine is 600˜10000.

6. A composite with synergistic effect of adsorption and visible light catalytic degradation, which is obtained according to the preparation method according to claim 1.

7. An application of the composite with synergistic effect of adsorption and visible light catalytic degradation according to claim 6 for removing organic contaminant with negative charge in water.

8. The application according to claim 7, wherein: said organic contaminant with negative charge is anionic dye.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG. 1. SEM images of bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite (ACF@BiOI.sub.xCl.sub.1-x), and the SEM images of ACF without nanoparticles on the top left corner.

[0029] FIG. 2. Photocatalytic degradation patterns of 50 mg/l AR 1 over PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 under 300 W Xenon lamp.

[0030] FIG. 3. Recycle of the PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 for AR 1 removal from water.

DETAILED DESCRIPTIONS

[0031] The invention will be made a further explanation according to the figures and the specific implementations. The chemicals, materials and instruments used in the following implementations can be obtained commercially.

[0032] Implementation 1: Preparation of bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite (ACF@BiOI.sub.0.5Cl.sub.0.5).

[0033] At room temperature, dissolving Bi(NO.sub.3).sub.3.5H.sub.2O (2 mmol) and ACF (50 mg) in ethylene glycol (20 mL), to get solution A.sub.1. Dissolving KI (1 mmol) and KCl (1 mmol) in ethylene glycol (20 mL), to get solution B.sub.1. Adding solution B.sub.1 dropwise to solution A.sub.1, stirring for 2 h, transferring to a hydrothermal reactor and reacting for 12 h at 160° C. After reaction, taking out the reaction kettle, cooling and opening to collect the fibrous product by filtration, washing separately with deionized water and 95% ethanol twice, placing in a vacuum oven to dry at 60° C. for 12 h, to obtain the product ACF@BiOI.sub.0.5Cl.sub.0.5, the SEM image is shown in FIG. 1.

[0034] As shown in FIG. 1, in the composite material ACF@BiOI.sub.0.5Cl.sub.0.5, the composite nanoparticles BiOI.sub.0.5Cl.sub.0.5 were spherical and evenly distributed on the ACF surface.

[0035] Implementation 2: Preparation of bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite (ACF@BiOI.sub.0.25Cl.sub.0.75).

[0036] At room temperature, dissolving Bi(NO.sub.3).sub.3.5H.sub.2O (2 mmol) and ACF (50 mg) in ethylene glycol (20 mL), to get solution A.sub.1. Dissolving KI (0.5 mmol) and KCl (1.5 mmol) in ethylene glycol (20 mL), to get solution B.sub.2. Adding solution B.sub.2 dropwise to solution A.sub.1, stirring for 2 h, transferring to a hydrothermal reactor and reacting for 12 h at 160° C. After reaction, taking out the reaction kettle, cooling and opening to collect the fibrous product by filtration, washing separately with deionized water and 95% ethanol twice, placing in a vacuum oven to dry at 60° C. for 12 h, to obtain the product ACF@BiOI.sub.0.25Cl.sub.0.75.

[0037] Implementation 3: Preparation of polyethyleneimine grafted bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite (PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5).

[0038] Taking 50 mg ACF@BiOI.sub.0.5Cl.sub.0.5 obtained in Implementation 1, dissolving in 30 mL N,N-Dimethylformamide (DMF), adding 50 μL (3-bromopropyl) trimethoxysilane, stirring in oil bath at 80° C. for 6 h, then adding 10 g 10% PEI aqueous solution (M.sub.w of polyethyleneimine is 1200), stirring for 6 h. After reaction, cooling and collecting the fibrous product by filtration, washing separately with deionized water and 95% ethanol twice, drying to a constant weight, to obtain PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5.

[0039] From the IR spectrum of the PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5, it can be seen that the absorption peak at 3245 cm.sup.−1 is the stretching vibration band of N—H on PEI. PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 kept sharp peaks on (110) (101) (102) of BiOI.sub.0.5Cl.sub.0.5 in its XRD pattern, which coexisted that of the pure BiOI and BiOCl (indexed by JCPDS Card no. 70-2062 and no. 06-0249, respectively), It also indicates that the BiOI.sub.0.5Cl.sub.0.5 nanoparticles immobilized on the ACF surface and the grafting of PEI tightly remains the original phase structure.

[0040] Implementation 4: Photocatalytic experiment of PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 towards Acid Red 1.

[0041] The 50 mg photocatalytic composites in implementation 3 were added into 50 ml AR 1 aqueous solution (50 mg/L) and stirred for 1.5 h in the illumination condition, the 3 ml suspension was analyzed every 10 min by UV-vis DRS at 530 nm, as shown in FIG. 2.

[0042] As shown in FIG. 2, the adsorption efficiency of PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 to AR 1 was reached at 60% in 10 min. The 50 mL solution containing 50 ppm AR 1 was totally degraded from wastewater after 60 min by 50 mg of PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5. The excellent degradation efficiency of composite to AR 1 is attributed to the big absorption capacity on the synergistic adsorption-degradation process.

[0043] Implementation 5: Recycle experiment of PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 towards Acid Red 1.

[0044] The recycle photocatalyst of PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 was continuously used for five cycles to degrade AR 1 solution under the same conditions. The 50 mg photocatalytic composites in implementation 4 were added into 50 ml AR 1 aqueous solution (50 mg/L) and stirred for 1.5 h in the illumination condition, the 3 ml suspension was analyzed every 10 min by UV-vis DRS at 530 nm, as shown in FIG. 3. After each cycle, PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 was taken from the aqueous solution without centrifugation and then was washed thoroughly for the adsorption-photodegradation of a next batch of fresh AR 1 solution.

[0045] As shown in FIG. 3, the 50 ppm AR 1 in 50 mL aqueous solution could be degraded completely by 50 mg PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 after recycled for five times, which meant the excellent photocatalytic performance of PEI-g-ACF@BiOI.sub.0.5Cl.sub.0.5 sample was still retained after reusing for several times without any regeneration process.