Preparation method of Cu-Co bimetallic semi-crystalline material and application of Cu-Co bimetallic semi-crystalline material to adsorption of dye

Abstract

The invention relates to a preparation method of a Cu-Co bimetallic semi-crystalline material and application of the Cu-Co bimetallic semi-crystalline material to adsorption of dye, and belongs to the field of preparation of nano materials and environmental materials, the Cu salt and the Co salt of the same type are weighed, the mass ratio is 1: 3-3: 1, the Cu salt and the Co salt are mixed in an ethanol solution, and the Cu salt and the Co salt are promoted to be dissolved and fully mixed through ultrasonic waves to be named as a solution A; adding an organic ligand into deionized water, and enabling the concentration of the organic ligand to be 0.2 mol / L by utilizing an auxiliary reagent under an ultrasonic condition, so as to obtain a solution B; mixing the solution A and the solution B according to the volume ratio of 1: 2, and stirring to a flowable liquid state under the condition of constant-speed stirring, so as to obtain a substance C; centrifugally collecting and drying the C substance to obtain a dried Cu-Co bimetallic semi-crystalline material; the preparation method of the Cu-Co bimetallic semi-crystalline material is simple, convenient, rapid and low in energy consumption, and the synthesized Cu-Co bimetallic semi-crystalline material has a multi-element pore structure, a large specific surface area and multi-element active sites and is high in adsorption capacity.

Description

Technical Field

[0001] The invention belongs to the field of nano material and environmental material preparation, and particularly relates to a preparation method of a Cu-Co bimetallic semi-crystalline material and its application in dye adsorption. Background Art

[0002] With the rapid development of industry, textile, papermaking, clothing, and cosmetics, organic dyes including Congo red, methyl blue, methyl orange, and rhodamine B are widely used. The use of these substances will produce highly polluting dye wastewater. Dye wastewater has poor biodegradability, high chromaticity, and large changes in water quality and quantity, and is difficult to be effectively treated by conventional water treatment technology. When wastewater carrying dyes enters natural water bodies, it will damage the ecosystem and threaten the growth of plants and animals. Therefore, there is an urgent need for an effective treatment method for removing dyes from water bodies.

[0003] Semi-crystalline materials are a special type of material between metal-organic framework materials and metal-organic gel materials. They have a rich pore structure, multiple active sites and a large specific surface area, which can promote the mass transfer process of pollutants in the water body within the material and help them to be quickly adsorbed and removed in the water body. In particular, due to the different binding abilities of different metal ions with organic ligands during the preparation process, the pore structure of bimetallic semi-crystalline materials will be more complete, which can improve the capture and removal of pollutants in the water body. However, most of the preparation processes of semi-crystalline materials require a lot of energy and chemicals, and the preparation time is long, which is not conducive to energy conservation and environmental protection and practical application. Therefore, the simple method of preparing bimetallic semi-crystalline materials still faces challenges. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the above-mentioned background technology, and to provide a preparation method of Cu-Co bimetallic semi-crystalline material and its application in dye adsorption. The method is simple to operate, has high material yield, low energy consumption, and short preparation time. The prepared bimetallic semi-crystalline material has a rich pore structure, multiple active sites and a large specific surface area, and realizes the rapid adsorption and removal of high-concentration dyes in water.

[0005] A method for preparing a Cu-Co bimetallic semi-crystalline material comprises the following steps: Step 1: Weigh the same type of Cu salt and Co salt, where the salt type can be nitrate, sulfate or chloride, and the mass ratio of Cu salt to Co salt is 1:3 to 3:1, mix them in an ethanol solution, and use ultrasound to promote the dissolution and thorough mixing of the two. The concentration of the mixed solution is 0.25 mol / L, and it is named solution A; Step 2: Weigh a certain amount of organic ligand, add it to deionized water, and use auxiliary reagents to promote its dissolution in water under ultrasonic conditions, so that the concentration of the organic ligand is 0.2 mol / L, named B solution, and the volume ratio of B solution to auxiliary reagent is 10:1 to 40:1; Step 3: Mix solutions A and B in a volume ratio of 1:2, and stir at a constant speed until they become a flowable liquid, which is named substance C; Step 4: Collect the C substance obtained in step 3 by centrifugation, wash it with ethanol several times to remove excess ion solution and organic ligands, and dry it in an oven at 45 degrees to obtain a dry Cu-Co bimetallic semi-crystalline material.

[0006] The organic ligand used in the step 2 is terephthalic acid, trimesic acid, nitrobenzoic acid or aminobenzoic acid.

[0007] The auxiliary reagent used in step 2 is either trimethylamine or triethylamine.

[0008] The Cu-Co bimetallic semi-crystalline material prepared according to the above method is used for adsorption of dyes in water, and the dosage of the Cu-Co bimetallic semi-crystalline material is 0.5 g / L.

[0009] Beneficial effects of the present invention: The method for preparing the Cu-Co bimetallic semi-crystalline material provided by the present invention is a simple, fast and low-energy method. The prepared Cu-Co bimetallic semi-crystalline material can be used as an adsorbent for dyes in water to achieve the purpose of rapid adsorption and removal of dyes.

[0010] The preparation method of the Cu-Co bimetallic semi-crystalline material of the present invention is simple, fast and has low energy consumption. The synthesized Cu-Co bimetallic semi-crystalline material has a multi-element pore structure, a large specific surface area and multi-element active sites, and the adsorption amount of dyes in water can reach 3980.11 mg / g. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a BET diagram of the Cu-Co bimetallic semi-crystalline material prepared by the present invention; Figure 2 is a pore size distribution diagram of the Cu-Co bimetallic semi-crystalline material prepared by the present invention; Figure 3 This is an infrared spectrum of the Cu-Co bimetallic semi-crystalline material prepared by the present invention; Figure 4 This is a diagram showing the adsorption effect of the Cu-Co bimetallic semi-crystalline material prepared by the present invention on dyes in water. DETAILED DESCRIPTION Example 1

[0012] A method for preparing a Cu-Co bimetallic semi-crystalline material comprises the following steps: Step 1: Weigh Cu(NO3)2 and Co(NO3)2 in a mass ratio of 1:3, mix them in an appropriate amount of ethanol solution, and use ultrasound to promote the dissolution and thorough mixing of the two. The concentration of the mixed solution is 0.25 mol / L, named solution A; Step 2: Weigh a certain amount of nitrobenzoic acid, add it to deionized water, and use trimethylamine as an auxiliary reagent to promote its dissolution in water under ultrasonic conditions, so that the concentration of nitrobenzoic acid is 0.2 mol / L, named solution B, and the volume ratio of solution B to trimethylamine is 10:1; Step 3: Mix solutions A and B in a volume ratio of 1:2, and stir at a constant speed until they become a flowable liquid, which is named substance C; Step 4: Collect the C substance obtained in step 3 by centrifugation, wash it with ethanol three times to remove excess ion solution and nitrobenzoic acid, and dry it in an oven at 45 degrees to obtain a dry Cu-Co bimetallic semi-crystalline material. Example 2

[0013] A method for preparing a Cu-Co bimetallic semi-crystalline material comprises the following steps: Step 1: Weigh CuSO4 and CoSO4 in a mass ratio of 1:1, mix them in an appropriate amount of ethanol solution, and use ultrasound to promote the dissolution and thorough mixing of the two. The concentration of the mixed solution is 0.25 mol / L, named solution A; Step 2: Weigh a certain amount of terephthalic acid, add it to deionized water, and use triethylamine as an auxiliary reagent to promote its dissolution in water under ultrasonic conditions, so that the concentration of terephthalic acid is 0.2 mol / L, named B solution, and the volume ratio of B solution to triethylamine is 20:1; Step 3: Mix solutions A and B in a volume ratio of 1:2, and stir at a constant speed until they become a flowable liquid, which is named substance C; Step 4: Collect the C substance obtained in step 3 by centrifugation, wash it with ethanol 4 times to remove excess ion solution and terephthalic acid, and dry it in an oven at 45 degrees to obtain a dry Cu-Co bimetallic semi-crystalline material. Example 3

[0014] A method for preparing a Cu-Co bimetallic semi-crystalline material comprises the following steps: Step 1: Weigh CuCl2 and CoCl in a mass ratio of 3:1 2， Mix them in an appropriate amount of ethanol solution, and use ultrasound to promote their dissolution and thorough mixing. The concentration of the mixed solution is 0.25 mol / L, and is named solution A. Step 2: Weigh a certain amount of aminobenzoic acid, add it to deionized water, and use trimethylamine as an auxiliary reagent to promote its dissolution in water under ultrasonic conditions, so that the concentration of aminobenzoic acid is 0.2 mol / L, named B solution, and the volume ratio of B solution to trimethylamine is 40:1; Step 3: Mix solutions A and B in a volume ratio of 1:2, and stir at a constant speed until they become a flowable liquid, which is named substance C; Step 4: Collect the C substance obtained in step 3 by centrifugation, wash it with ethanol 5 times to remove excess ion solution and aminobenzoic acid, and dry it in an oven at 45 degrees to obtain a dry Cu-Co bimetallic semi-crystalline material. Example 4

[0015] The Cu-Co bimetallic semi-crystalline material prepared in Example 1 is used as an adsorbent to adsorb and remove Congo red dye in water.

[0016] In practical applications, the adsorbent provided in this embodiment can be used to remove Congo red dye from water by the following scheme: 100 mg / L, 500 mg / L, 1000 mg / L, 1500 mg / L, 2000 mg / L, 3000 mg / L and 4000 mg / L Congo red solution is prepared, 0.5 g / L of Cu / Co bimetallic semi-crystalline material is added, and samples are taken regularly at a temperature of 25 degrees, and filtered using a 0.22 μm membrane filter. The concentration of the remaining Congo red in the water is measured at a wavelength of 497 nm, and the adsorption amount of Congo red by the material is calculated. According to the isotherm model fitting results, the Cu-Co bimetallic semi-crystalline material involved in Example 1 can adsorb 3980.11 mg / g of dye in water.

Claims

1. A method for preparing a Cu-Co bimetallic semi-crystalline material, characterized in that: The steps include: Step 1: Weigh the same type of Cu salt and Co salt, where the salt type can be nitrate, sulfate or chloride, and the mass ratio of Cu salt to Co salt is 1:3 to 3:1, mix them in an ethanol solution, and use ultrasound to promote the dissolution and thorough mixing of the two. The concentration of the mixed solution is 0.25 mol / L, and it is named solution A; Step 2: Weigh a certain amount of organic ligand, add it to deionized water, and use auxiliary reagents to promote its dissolution in water under ultrasonic conditions, so that the concentration of the organic ligand is 0.2 mol / L, named B solution, and the volume ratio of B solution to auxiliary reagent is 10:1 to 40:1; Step 3: Mix solutions A and B in a volume ratio of 1:2, and stir at a constant speed until they become a flowable liquid, which is named substance C; Step 4: Collect the C substance obtained in step 3 by centrifugation, wash it with ethanol several times to remove excess ion solution and organic ligands, and dry it in an oven at 45 degrees to obtain a dry Cu-Co bimetallic semi-crystalline material.

2. The method for preparing a Cu-Co bimetallic semi-crystalline material according to claim 1, characterized in that: The organic ligand used in the step 2 is terephthalic acid, trimesic acid, nitrobenzoic acid or aminobenzoic acid.

3. The method for preparing a Cu-Co bimetallic semi-crystalline material according to claim 1, characterized in that: The auxiliary reagent used in step 2 is either trimethylamine or triethylamine.

4. The application of the Cu-Co bimetallic semi-crystalline material prepared by the method according to claim 1 to adsorb dyes in water is characterized by: The dosage of the Cu-Co bimetallic semi-crystalline material is 0.5 g / L.

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