Preparation method and application of copper chloride modified vinegar residue biochar

Abstract

A method for preparing and applying copper chloride-modified vinegar residue biochar, belonging to the field of wastewater treatment technology, is disclosed. The method involves: weighing 1.0000 g ± 0.0005 g of vinegar residue powder and adding it to 40 mL of ultrapure water, dispersing it thoroughly under magnetic stirring; then adding 0.5000 g of CuCl₂·2H₂O, mixing, and continuously stirring magnetically at room temperature for 24 h to allow the CuCl₂ to form a biochar. 2+ The mixture is thoroughly impregnated with vinegar residue to form a mixture. The mixture is then dried in an oven and transferred to a tube furnace. Inside the tube furnace, under a N₂ atmosphere, the temperature is increased to 600°C at 8°C / min and pyrolyzed for 120 min. After cooling, the product is removed, ground, and then copper chloride-modified vinegar residue biochar is obtained. This invention features a simple process flow, controllable operating conditions, low equipment requirements, good repeatability, and suitability for large-scale preparation. The obtained copper chloride-modified vinegar residue biochar exhibits excellent adsorption and degradation performance of organic pollutants, particularly efficient degradation and removal of quinolone antibiotics such as ciprofloxacin and norfloxacin.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, and specifically relates to a method for preparing and applying copper chloride-modified vinegar residue biochar (BC-NCu). The copper chloride-modified vinegar residue biochar prepared by this invention can degrade organic pollutants, and is particularly efficient in degrading and removing quinolone antibiotics, such as ciprofloxacin (CIP) and norfloxacin (NOR). Background Technology

[0002] Wastewater treatment plants are the main sites for wastewater treatment. In order to meet the requirements of indicators such as COD, BOD, and ammonia nitrogen, most wastewater treatment plants adopt the activated sludge process. However, because antibiotics have a sterilizing effect, conventional water treatment methods are not very effective in removing antibiotics, and there is an urgent need to develop new treatment technologies.

[0003] Quinolone antibiotics are widely used in medicine and aquaculture. Their residues in water bodies can lead to the emergence of drug-resistant bacteria and the spread of drug resistance, posing a serious threat to ecosystems and human health.

[0004] In recent years, with the promotion of the concept of green circular economy, vinegar residue, as the main solid waste generated in the vinegar brewing process, has gradually received attention for resource utilization and high-value utilization. According to statistics, my country produces about 3 million tons of vinegar residue every year, but the traditional treatment methods are mainly composting, landfilling or incineration, and the comprehensive utilization rate is less than 50%. Vinegar residue is rich in organic carbon, cellulose and a variety of minerals, and has excellent modification potential, making it an ideal raw material for the preparation of biochar. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing copper chloride-modified vinegar residue biochar and its application. The copper chloride-modified vinegar residue biochar prepared by this method can efficiently degrade and remove quinolone antibiotics, such as ciprofloxacin (CIP) and norfloxacin (NOR).

[0006] A method for preparing copper chloride-modified vinegar residue biochar includes the following steps: 1) Weigh 1.0000g ± 0.0005g of vinegar residue powder and add it to 40mL of ultrapure water. Disperse the powder thoroughly under magnetic stirring. Then add 0.5000g of CuCl2·2H2O, mix, and continue magnetic stirring at room temperature for 24h to allow the Cu... 2+ Fully soaked in vinegar residue to form a mixture; 2) The mixture was dried in an oven and then transferred to a tube furnace. In the tube furnace, the temperature was increased to 600℃ at 8℃ / min under N2 atmosphere and pyrolyzed for 120min. After cooling, the product was taken out and ground to obtain copper chloride modified vinegar residue biochar.

[0007] The copper chloride-modified vinegar residue biochar prepared by this method can be used to degrade and remove quinolone antibiotics, such as ciprofloxacin (CIP) and norfloxacin (NOR).

[0008] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Using vinegar residue as a biochar precursor, taking advantage of its high carbon content and stable source, the resource utilization of industrial by-products is realized. The preparation cost is low, which is in line with the technical route of green and sustainable development.

[0009] 2. By impregnating the vinegar residue powder with CuCl2·2H2O before pyrolysis, copper elements can be evenly distributed inside and on the surface of the biomass of the vinegar residue, and can be loaded in situ into the biochar structure of the vinegar residue during the subsequent high-temperature pyrolysis process, thus avoiding the agglomeration and loss of metal active components during the preparation process.

[0010] 3. High-temperature pyrolysis under a nitrogen protective atmosphere effectively prevents the oxidation and burn-off of carbon materials, ensuring the integrity of the biochar skeleton structure and giving the resulting modified biochar a stable structure and good porosity.

[0011] 4. By introducing the transition metal copper, the number of active sites on the surface of copper chloride-modified vinegar residue biochar is significantly increased without destroying the porous structure of the vinegar residue biochar, thereby improving the activation ability of copper chloride-modified vinegar residue biochar for persulfate and enhancing its catalytic degradation performance for organic pollutants. The copper chloride-modified vinegar residue biochar prepared by this invention is particularly capable of efficiently degrading and removing quinolone antibiotics, such as ciprofloxacin (CIP) and norfloxacin (NOR).

[0012] 5. Copper chloride-modified vinegar residue biochar has a specific surface area of ​​350-500 m². 2 It has a capacity of / g, and its adsorption efficiency is improved by 20%-30% in adsorbing heavy metals and organic pollutants, demonstrating excellent adsorption performance.

[0013] 6. The process of this invention is simple, the operating conditions are controllable, the equipment requirements are low, the repeatability is good, and it is suitable for large-scale preparation. The resulting copper chloride modified vinegar residue biochar has good application prospects in the field of water pollution control. Detailed Implementation

[0014] A method for preparing copper chloride-modified vinegar residue biochar includes the following steps: 3) Weigh 1.0000g ± 0.0005g of vinegar residue powder and add it to 40mL of ultrapure water. Disperse the powder thoroughly under magnetic stirring. Then add 0.5000g of CuCl2·2H2O, mix, and continue magnetic stirring at room temperature for 24h to allow the Cu... 2+ Fully soaked in vinegar residue to form a mixture; 4) The mixture was dried in an oven and then transferred to a tube furnace. In the tube furnace, the temperature was increased to 600℃ at 8℃ / min under N2 atmosphere and pyrolyzed for 120min. After cooling, the product was taken out and ground to obtain copper chloride modified vinegar residue biochar.

[0015] The copper chloride-modified vinegar residue biochar prepared by this method can be used to degrade and remove quinolone antibiotics, such as ciprofloxacin (CIP) and norfloxacin (NOR).

[0016] The degradation mechanism of copper chloride-modified vinegar residue biochar is as follows: In the degradation system of copper chloride-modified vinegar residue biochar, Cu 0 Provide electrons to HSO5 - Converted to SO4• - Cu + With HSO5 - The reaction produces SO4• - and Cu 2+ Cu 2+ With HSO5 - The reaction produces O2• - and Cu + Cu 0 The valence state changes of Cu⁺ and Cu²⁺ enable continuous activation of PMS, generating free radicals such as SO₄•⁻ and O₂•⁻. Simultaneously, O₂•⁻ conversion, PMS self-decomposition, and direct activation of persulfate (PMS) by C=O functional groups on the biochar surface jointly generate ¹O₂, forming a synergistic oxidation mechanism of free radicals and non-free radicals, thereby achieving efficient degradation of CIP and NOR.

[0017] Degradation effect of copper chloride-modified vinegar residue biochar: The degradation efficiency of ciprofloxacin solution with a concentration of 20 mg / L was 97.66% when the persulfate (PMS) concentration was 0.5 mM, the catalyst dosage was 0.3 g / L, and the pH was 3. The degradation efficiency of norfloxacin solution with a concentration of 20 mg / L was 94.19%.

Claims

1. A method for preparing copper chloride-modified vinegar residue biochar, characterized in that: Includes the following steps: 1) Weigh 1.0000g ± 0.0005g of vinegar residue powder and add it to 40mL of ultrapure water. Disperse the powder thoroughly under magnetic stirring. Then add 0.5000g of CuCl2·2H2O, mix, and continue magnetic stirring at room temperature for 24h to allow the Cu... 2+ Fully soaked in vinegar residue to form a mixture; 2) The mixture was dried in an oven and then transferred to a tube furnace. In the tube furnace, the temperature was increased to 600℃ at 8℃ / min under N2 atmosphere and pyrolyzed for 120min. After cooling, the product was taken out and ground to obtain copper chloride modified vinegar residue biochar.

2. The copper chloride-modified vinegar residue biochar according to claim 1 is used to degrade and remove quinolone antibiotics.