Copper slag derived ferrotitanium piezoelectric material and application thereof

Abstract

The invention discloses a copper slag-derived ferrotitanium piezoelectric material which is prepared by the following steps: calcining copper slag at 500-700 DEG C, crushing and sieving the calcined product, mixing with titanium dioxide and starch, performing dry grinding on the mixture for 1-3 hours, and calcining at 500-700 DEG C in an inert atmosphere, thereby obtaining the copper slag-derived ferrotitanium piezoelectric material, the ferrotitanium piezoelectric material prepared by the method has the advantages of high specific surface area, multiple reaction active sites, good catalytic performance, stable structure and the like, can be used for activating persulfate to degrade tetracycline hydrochloride, is remarkable in catalyst removal effect, and has good application value and application prospect.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solid waste secondary utilization, and particularly relates to a preparation method of a copper slag derived iron-titanium piezoelectric material and application of the copper slag derived iron-titanium piezoelectric material in removal of tetracycline hydrochloride. BACKGROUND

[0002] Emerging Pollutants (EPs) have posed a serious threat to water ecosystems and human health due to their poor biodegradability, wide environmental distribution, and high biological toxicity. Tetracycline hydrochloride (TC) is a typical EP, and its persistent residues and ecological toxicity in the water environment make it a key target for pollution control. Studies have shown that about 80% of antibiotics are excreted into the sewage system, and the removal efficiency of traditional sewage treatment processes is limited, leading to the increasingly serious accumulation of antibiotics in surface water and groundwater. In recent years, Sulfate Radical-based Advanced Oxidation Processes (SR-AOPs) based on the activation of persulfate (PMS) have attracted much attention in the field of organic wastewater treatment due to their strong oxidizing ability, wide pH adaptability, and long half-life of active free radicals. However, traditional heat / electrically driven PMS activation has the problem of slow kinetics, leading to an increase in chemical reagent dosage and operating costs.

[0003] Piezoelectric Catalysis (PC) is a technology that utilizes the piezoelectric polarization of materials under mechanical external force to release polarization charges to drive chemical reactions. In the process of advanced oxidation based on persulfate (PMS), these polarization charges can participate in the breaking of the O-O bond in the PMS molecule, thereby significantly increasing the yield of active oxygen species (ROS) such as sulfate radicals (SO4· - ), hydroxyl radicals (·OH), and singlet oxygen ( 1 O2). Compared with traditional PMS activation processes that rely on electrical or thermal energy, PC-PMS technology has the advantages of low equipment dependence and the ability to directly utilize environmental mechanical energy (such as water flow, ultrasound, vibration). Ferroelectric materials can respond to external fields (such as mechanical stress) in real time due to their spontaneous polarization characteristics, making them attractive in the field of advanced catalysis. Among them, iron titanate (FeTiO3) is a typical semiconductor material that has excellent chemical stability and potential piezoelectric catalytic activity. However, FeTiO3 still faces two major challenges in practical applications: (1) low carrier (electron / hole) transport efficiency, which limits the effective separation and utilization of charges; (2) insufficient stability in complex reaction environments, especially the problem of iron element leaching. SUMMARY

[0004] This invention provides a copper slag-derived iron-titanium piezoelectric material with high specific surface area, multiple reactive sites, good catalytic performance, and stable structure, which can efficiently activate persulfate. It also provides a simple process, abundant raw material reserves, low cost and easy availability, and environmentally friendly preparation method for the copper slag-derived iron-titanium piezoelectric material. Furthermore, it provides the application of the copper slag-derived iron-titanium piezoelectric material in the treatment of tetracycline hydrochloride wastewater.

[0005] The objective of this invention is achieved through the following technical solution: 1. Weigh the copper slag and place it in a crucible. Calcinate it in a muffle furnace at 500-700℃ for 1-3 hours. Then, pulverize it through a 200-mesh sieve. Mix the calcined product, titanium dioxide, and starch in a stainless steel spherical ink jar and dry grind it in a planetary ball mill at 100-200 rpm for 1-3 hours to obtain the FeTiO3 / C precursor. The mass ratio of calcined product to titanium dioxide is 1:0.1-0.5, and the mass ratio of starch to calcined product is 1:5-30. 2. Place the FeTiO3 / C precursor in an alumina square crucible and calcine it at 500-700℃ for 1-3 hours under an inert atmosphere. After cooling to room temperature, grind it to obtain the copper slag-derived iron-titanium piezoelectric material.

[0006] 3. Utilize copper slag-derived iron-titanium piezoelectric materials to activate persulfate and degrade tetracycline hydrochloride in water. Specifically, mix the copper slag-derived iron-titanium piezoelectric materials with tetracycline hydrochloride wastewater, stir, and add persulfate to carry out a catalytic degradation reaction, thereby completing the degradation of tetracycline hydrochloride in the water.

[0007] The mass-to-volume ratio (mg:mL) of the copper slag-derived iron-titanium piezoelectric material to the tetracycline hydrochloride wastewater is 2-5:5; the concentration of persulfate in the reaction system is 0.5 mmol / L-2.5 mmol / L; the persulfate is potassium peroxymonosulfate; the concentration of tetracycline hydrochloride is 5 mg / L-50 mg / L, and the pH value is 3-11.

[0008] The present invention has the following advantages over the prior art: 1. This invention employs a simple dry grinding method combined with heat treatment to prepare copper slag-derived iron-titanium piezoelectric materials with advantages such as high specific surface area, numerous reactive sites, good piezoelectric properties, high metal atom utilization, and stable structure. This method can significantly improve the specific surface area of ​​the catalyst and enhance its catalytic efficiency. Meanwhile, the preparation method of the present invention is simple in process, convenient in operation, easy to obtain raw materials, low in cost, easy to realize industrial production, and has great application prospects, especially in the field of environmental catalysis. (2) The present invention utilizes copper slag-derived iron-titanium piezoelectric materials to activate persulfate and degrade tetracycline hydrochloride in water. Experimental results show that copper slag-derived iron-titanium piezoelectric materials can achieve efficient degradation of tetracycline hydrochloride by activating persulfate under ultrasonic conditions, and have good development prospects in the field of treating organic pollutants. Attached Figure Description

[0009] Figure 1 The XRD patterns are of the catalysts in Example 1 and Comparative Examples 1-3; Figure 2 SEM image of iron-titanium piezoelectric material derived from copper slag; Figure 3 The time-degradation efficiency graphs for the catalysts of Examples 1 and Comparative Examples 1-3 under ultrasonic conditions are shown. Figure 4 The graph shows the fitting of the degradation rate constants of the catalysts in Example 1 and Comparative Examples 1-3 under ultrasonic conditions for the degradation of tetracycline hydrochloride. Figure 5 The graph shows the cycle number and degradation efficiency of FeTiO3 / C, a copper slag-derived iron-titanium piezoelectric material, in the degradation of tetracycline hydrochloride under ultrasonic conditions. Figure 6 The images show the catalyst adsorption-desorption isotherms and pore size distribution diagrams for Examples 1 and Comparative Examples 1-3. Detailed Implementation

[0010] The following examples further illustrate the content of the present invention, but these examples do not limit the scope of protection of the present invention. Unless otherwise specified, the methods in the examples are conventional methods, and the reagents used are commercially available reagents unless otherwise specified. The main components of the copper slag used in the following examples are Fe2O3 73.79%, SiO2 10.47%, Al2O3 1.32%, CaO 3.02%, and ZnO 3.78%. Example 1: Preparation of iron-titanium piezoelectric materials derived from copper slag 1. Place the copper slag in a crucible and calcine it in a muffle furnace at 550℃ for 2 hours. Crush the calcined product through a 200-mesh sieve to obtain the calcined product (Fe2O3). The XRD pattern of the calcined product is shown below. Figure 1As can be seen from the figure, the sharp characteristic peaks at 2θ = 24.13°, 33.15°, 35.61°, 40.85°, 49.47°, 54.08°, 57.58°, 62.44° and 63.98° correspond to the (012), (104), (110), (113), (024), (116), (018), (214) and (300) crystal planes in the PDF card (PDF#33-0664) of Fe2O3, respectively. This indicates that the copper slag after calcination in the air contains a large amount of Fe2O3, in which the valence state of iron is a state in which divalent iron and trivalent iron coexist. 2. Mix 5g of the calcined product, 0.875g of titanium dioxide, and 0.25g of starch in a stainless steel spherical ink jar, and dry grind at 150 rpm for 2 hours in a planetary ball mill. Then, place the dry-ground material in an alumina square crucible and calcine at 550℃ for 2 hours under an inert atmosphere. After cooling to room temperature and grinding, the copper slag-derived iron-titanium piezoelectric material FeTiO3 / C is obtained. The XRD pattern of this material is shown below. Figure 1 As can be seen from the figure, the sharp characteristic peaks of the sample at 2θ = 29.96°, 35.29°, 36.94°, 42.92°, 53.26°, 56.77° and 62.34° correspond to the (220), (311), (222), (400), (422), (511) and (440) crystal planes in FeTiO3 (PDF#51-1587), respectively; its SEM image is shown in [image missing]. Figure 2 As can be seen from the figure, the material exhibits an irregular, aggregated morphology.

[0011] Comparative Example 1: The calcination product from step 1 of Example 1 was used as the catalyst for Comparative Example 1. Comparative Example 2: Preparation of the catalyst FeTiO3 Copper slag was weighed and placed in a crucible, then calcined at 550℃ for 2 hours in a muffle furnace. The calcined product was pulverized and passed through a 200-mesh sieve. 5g of the calcined product was mixed with 0.875g of TiO2 in a stainless steel spherical mill and dry-milled at 150rpm for 2 hours in a planetary ball mill. The dry-milled material was then placed in an alumina square crucible and calcined at 550℃ for 2 hours under an inert atmosphere. After cooling to room temperature and grinding, the catalyst FeTiO3 was obtained. Its XRD pattern is shown below. Figure 1 As can be seen from the figure, the sharp characteristic peaks of the sample at 2θ = 29.96°, 35.29°, 36.94°, 42.92°, 53.26°, 56.77° and 62.34° correspond to the (220), (311), (222), (400), (422), (511) and (440) crystal planes in FeTiO3 (PDF#51-1587), respectively.

[0012] Comparative Example 3: Preparation of the catalyst Fe2O3 / C Copper slag was weighed and placed in a crucible, then calcined at 550℃ for 2 hours in a muffle furnace. The calcined product was pulverized and passed through a 200-mesh sieve. 5g of the calcined product was mixed with 0.25g of starch in a stainless steel spherical mill and dry-milled at 150rpm for 2 hours in a planetary ball mill. The dry-milled material was then placed in an alumina square crucible and calcined at 550℃ for 2 hours under an inert atmosphere. After cooling to room temperature and grinding, the catalyst Fe2O3 / C was obtained. Its XRD pattern is shown below. Figure 1 As can be seen from the figure, the sharp characteristic peaks at 2θ = 24.13°, 33.15°, 35.61°, 40.85°, 49.47°, 54.08°, 57.58°, 62.44° and 63.98° correspond to the (012), (104), (110), (113), (024), (116), (018), (214) and (300) crystal planes in the PDF card (PDF#33-0664) of Fe2O3, respectively.

[0013] Example 2: The catalysts in Example 1 and Comparative Examples 1-3 were used to treat tetracycline hydrochloride wastewater under ultrasonic conditions. 1. Weigh 40 mg of each catalyst from Example 1 and Comparative Examples 1-3, and place them in 50 mL of tetracycline hydrochloride solution with a concentration of 20 mg / L (pH=7). After mixing evenly, quickly add 22.5 mg of potassium persulfate and react under ultrasonic conditions (ultrasonic frequency of 30 kHz) in an ultrasonic oscillator at 25 °C. Take 5 mL of the reaction product using a syringe at 2, 5, 10, and 15 min, and separate the solid and liquid through a 0.22 μm filter. Measure the absorbance of the liquid at a wavelength of 357 nm using a UV spectrophotometer and calculate the concentration of the remaining tetracycline hydrochloride in the reaction solution. The degradation efficiency results are shown in the figure. Figure 3 The fitting results for the degradation rate constant are shown in [the table]. Figure 4 In summary, it can be seen that the copper slag-derived iron-titanium piezoelectric material FeTiO3 / C in Example 1 achieved a 100% degradation rate of tetracycline hydrochloride within 15 minutes, demonstrating superior catalytic degradation performance compared to other catalysts. The adsorption-desorption isotherms and pore size distribution diagrams of the catalyst are shown below. Figure 5 As can be seen from the figure, the FeTiO3 / C iron-titanium piezoelectric material derived from copper slag in Example 1, compared with the FeTiO3 catalyst prepared in Comparative Example 2, has a specific surface area and total pore volume of 2.0966 m². 2 ·g -1 and 0.011414 cm 3 ·g -1 The growth was 6.1105 m 2 ·g -1 and 0.027294 cm3 ·g -1 The specific surface area and pore volume of the catalyst are 2.91 and 2.39 times that of FeTiO3 catalyst, respectively. This may be due to the stable carbon film structure formed after the carbon source is calcined, which reduces the interaction force between particles and effectively inhibits the agglomeration of the sample surface, thereby increasing the specific surface area and pore volume of the catalyst.

[0014] 2. Weigh 40 mg of each catalyst from Example 1 and Comparative Examples 1-3, and place them in 50 mL of tetracycline hydrochloride solution with a concentration of 20 mg / L (pH=7). After mixing evenly, quickly add 22.5 mg of potassium persulfate and react under ultrasonic conditions (ultrasonic frequency of 30 kHz) in an ultrasonic oscillator at 25 °C to complete one cycle. The FeTiO3 / C iron-titanium piezoelectric material derived from copper slag in Example 1 was collected by magnetic separation. After being washed three times with deionized water and anhydrous ethanol, it was dried in a 60°C forced-air drying oven. After the sample was dried, the next cycle was carried out. The experimental conditions of each cycle were kept consistent, and the cycle was repeated five times. The degradation results of tetracycline hydrochloride solution by the catalyst at different cycle numbers are shown in the figure. Figure 6 As can be seen from the figure, the copper slag-derived iron-titanium piezoelectric material FeTiO3 / C can still degrade 93.1% of tetracycline hydrochloride after 5 cycles of use. This indicates that the copper slag-derived iron-titanium piezoelectric material FeTiO3 / C has high stability and strong activation performance.

[0015] Example 3: Preparation and application of iron-titanium piezoelectric materials derived from copper slag 1. Place the copper slag in a crucible and calcine it in a muffle furnace at 700℃ for 1 hour. Crush the calcined product through a 200-mesh sieve to obtain the calcined product. 2. Mix 5g of calcined product, 1.5g of titanium dioxide and 0.5g of starch in a stainless steel ball mill, place it in a planetary ball mill and dry grind at 150rpm for 2h. Then place the dry-ground material in an alumina square crucible and calcine at 700℃ for 1h in an inert atmosphere. After cooling to room temperature and grinding, the copper slag-derived iron-titanium piezoelectric material FeTiO3 / C is obtained. 3. 40 mg of catalyst FeTiO3 / C was placed in 50 mL of tetracycline hydrochloride solution with a concentration of 20 mg / L (pH=7). After mixing evenly, 22.5 mg of potassium persulfate was quickly added. The reaction was carried out under ultrasonic conditions (ultrasonic frequency of 30 kHz) in an ultrasonic oscillator at 25 °C. The degradation rate of tetracycline hydrochloride was 94.6% after 15 min.

Claims

1. A copper slag-derived iron-titanium piezoelectric material, characterized in that: Copper slag is calcined at 500-700℃. The calcined product is crushed and sieved, then mixed with titanium dioxide and starch. The mixture is dry-ground for 1-3 hours and then calcined at 500-700℃ in an inert atmosphere to obtain copper slag-derived iron-titanium piezoelectric materials.

2. The copper slag-derived iron-titanium piezoelectric material according to claim 1, characterized in that: The mass ratio of calcined product to titanium dioxide is 1:0.1-0.5, and the mass ratio of starch to calcined product is 1:5-30.

3. The copper slag-derived iron-titanium piezoelectric material according to claim 1, characterized in that: Dry grinding is carried out in a planetary ball mill with a rotation speed of 100-200 rpm.

4. The application of the copper slag-derived iron-titanium piezoelectric material according to any one of claims 1-3 in the catalytic degradation of tetracycline hydrochloride.

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