A cerium peroxide material for removing antimony(III), preparation method and use

Abstract

A cerium peroxide material for removing antimony III, a preparation method and use thereof; the preparation method comprises the following steps: dissolving cerium nitrate in deionized water to obtain a cerium nitrate solution with a concentration of 0.01 to 0.15 mol / L; adding hydrogen peroxide to the cerium nitrate solution, with the mixing molar ratio of the two being 1:(0.5 to 1.5); adjusting the pH value of the obtained solution to 7.0 with a 5 to 15% NH3 solution to obtain a suspension; washing the suspension several times, freeze-drying it, grinding it, and passing it through a 100 to 300 mesh sieve to obtain a cerium peroxide material P‑CeO x This solution does not require additional preparation of microsphere structure, but directly synthesizes cerium peroxide material, which simplifies the preparation process of antimony III removal material; on the other hand, the removal rate of antimony III by cerium peroxide material is as high as 97.6%, which solves the problem that the existing antimony III removal material cannot have both high efficiency and ease of preparation.

Description

Technical Field

[0001] The present invention relates to the field of pollution adsorption materials, and particularly to a cerium peroxide material for removing antimony(III), a preparation method and uses thereof. Background Art

[0002] Antimony (Sb) is an emerging toxic heavy metal pollutant. In soil, sediment, water and biological systems, the problem of antimony pollution poses potential health-related risks to humans and animals, which has attracted great attention. The US Environmental Protection Agency and many countries including the European Union and China have listed Sb as a priority pollutant. The World Health Organization stipulates that the sanitary standard of antimony in drinking water is 20 μg / L. While the concentration limit of antimony in the "GB3838-2002 Surface Water Environmental Quality Standard" in China is 0.005 mg / L. In the environment, Sb mainly exists in two inorganic oxidation states: antimony(III) and antimony(V). Under anaerobic conditions, Sb mainly exists in the form of antimony(III). The absorption rate of antimony(III) by crops is higher than that of antimony(V), and the toxicity of antimony(III) is higher than that of antimony(V). The pollution of antimony(III) poses a serious threat to environmental safety, and there is an urgent need for an economical and effective treatment technology. Existing materials for highly efficient oxidation and removal of antimony(III) generally prepare a microsphere structure, adsorb antimony(III) through the microsphere structure, and then add an antimony-removing active ingredient to the microsphere structure. In this way, the preparation of antimony removal requires both the preparation of the microsphere structure and the loading of the antimony-removing active ingredient, resulting in a complex preparation method for antimony removal, high cost, and unstable antimony removal efficiency. Summary of the Invention

[0003] The purpose of the present invention is to propose a preparation method of a cerium peroxide material for removing antimony(III), which has both high efficiency in removing antimony(III) and simplicity in preparation.

[0004] To achieve this purpose, the present invention adopts the following technical solutions:

[0005] A preparation method of a cerium peroxide material for removing antimony(III) includes the following steps:

[0006] (1) Take cerium nitrate and dissolve it in deionized water. After uniform dissolution, a cerium nitrate solution with a concentration of 0.01 - 0.15 mol / L is obtained;

[0007] (2) Add the cerium nitrate solution in step (1) to 20 - 40% hydrogen peroxide, and the mixed molar ratio of the two is 1:(0.5 - 1.5), and stir;

[0008] (3) Use 5 - 15% NH 3 solution to adjust the pH of the solution obtained in step (2) to 7.0, stir, and respectively obtain a suspension;

[0009] (4) Rinse the suspension with deionized water several times, freeze-dry and grind, and pass through a 100-300 mesh sieve to obtain the cerium peroxide material P-CeO x .

[0010] Preferably, in step (2), the molar ratio of the cerium nitrate solution to hydrogen peroxide is 1:1;

[0011] In the step (4), the cerium oxide material P-CeO x -1:1.0.

[0012] Preferably, in step (2), the concentration of the cerium nitrate solution is 0.080 mol / L.

[0013] A cerium peroxide material for removing antimony III is prepared by the above-mentioned method for preparing a cerium peroxide material for removing antimony III, and has a pore structure distributed on the surface.

[0014] A use of a cerium peroxide material in preparing an antimony III removal material, wherein the cerium peroxide material is the above-mentioned cerium peroxide material for removing antimony III.

[0015] A cerium peroxide material is used in oxidation to remove antimony III. The cerium peroxide material is the above-mentioned cerium peroxide material for removing antimony III.

[0016] Compared with the prior art, one of the above technical solutions has the following beneficial effects:

[0017] According to the above-mentioned preparation method, this scheme can prepare a cerium peroxide material with a rich porous structure on the surface. On the one hand, the preparation method is simple and does not require additional preparation into a microsphere structure, but the cerium peroxide material can be directly synthesized, which simplifies the preparation process of the antimony (III) removal material; on the other hand, the cerium peroxide material has a removal rate of antimony (III) as high as 97.6%, which solves the problem that the existing antimony (III) removal materials cannot have both high efficiency and ease of preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The cerium peroxide (P-CeO x -1:1.0) SEM image;

[0019] Figure 2 The cerium oxide (CeO 2 )

[0020] Figure 3 is a graph showing the adsorption kinetics of antimony (III) by cerium oxide and cerium peroxide prepared at different molar ratios of Ce to hydrogen peroxide in Example 2;

[0021] Figure 4 It is the kinetic curve diagram of the oxidation effect of cerium peroxide prepared from cerium oxide and different molar ratios of Ce to hydrogen peroxide on antimony(III) in Example 3;

[0022] Figure 5 It is in Example 4 that a small amount of hydroxyl radicals are generated during the reaction of CeO 2 with antimony(III), and it is the electron spin spectrum diagram;

[0023] Figure 6 It is in Example 4 that a small amount of superoxide radicals are generated during the reaction of CeO 2 with antimony(III), and it is the electron spin spectrum diagram;

[0024] Figure 7 It is the isothermal adsorption curve diagram of cerium oxide on antimony(III) in Example 5.

[0025] Figure 8 It is the isothermal adsorption curve diagram of cerium peroxide material (P-CeO x -1:1) on antimony(III) in Example 5. Detailed implementation manners

[0026] The embodiments of the present invention are described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described by referring to the drawings below are exemplary and are only used to explain the present invention and cannot be understood as a limitation to the present invention.

[0027] To facilitate the understanding of the present invention, the present invention is described more comprehensively below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure content of the present invention more thorough and comprehensive. For those not specified in the embodiments regarding specific technologies or conditions, they are carried out according to the technologies or conditions described in the literature in this field or according to the product specifications. For the reagents or instruments not specified for the manufacturers, they are all conventional products that can be obtained through commercial purchase.

[0028] A preparation method of a cerium peroxide material for removing antimony(III) includes the following steps:

[0029] (1) Take cerium nitrate and dissolve it in deionized water. After uniform dissolution, a cerium nitrate solution with a concentration of 0.01 - 0.15 mol / L is obtained;

[0030] (2) Add the cerium nitrate solution in step (1) to 20 - 40% hydrogen peroxide, and the mixed molar ratio of the two is 1:(0.5 - 1.5), and stir;

[0031] (3) Use 5-15% NH 3 The solution obtained in step (2) was adjusted to pH = 7.0, stirred, and suspensions were obtained respectively;

[0032] Cerium nitrate is added to hydrogen peroxide to obtain cerium peroxide, and then after the pH is adjusted to 7, cerium peroxide can be precipitated to obtain a suspension of cerium peroxide material; this scheme uses NH 3 The solution mainly needs the pH to change slowly so that cerium oxide can precipitate at the most stable rate, ensuring that the formed material structure is more uniform and stable.

[0033] (4) Rinse the suspension with deionized water several times, freeze-dry and grind, and pass through a 100-300 mesh sieve to obtain the cerium peroxide material P-CeO x .

[0034] After the suspension is dried and ground, its surface has a rich porous structure, and small nanoparticles are evenly distributed on the stacked flakes. Its specific surface area is large, which is very suitable for the removal of antimony (III).

[0035] The present invention provides a method for preparing a cerium peroxide material for removing antimony (III), which is based on mixing cerium nitrate and hydrogen peroxide in a molar ratio of 1: (0.5-1.5) to prepare a cerium peroxide material P-CeO x , has the ability to remove antimony (III) through oxidation mechanism, which is better than CeO 2 It has a better antimony (III) removal effect, and solves the problem that the existing antimony (III) removal materials cannot have both high efficiency and ease of preparation.

[0036] Preferably, in step (2), the molar ratio of the cerium nitrate solution to hydrogen peroxide is 1:1;

[0037] In the step (4), the cerium oxide material P-CeO x -1:1.0.

[0038] Cerium Oxide Material P-CeO x -1:1.0 refers to the cerium peroxide material obtained by mixing cerium nitrate solution and hydrogen peroxide at the optimal mixing molar ratio of 1:1.0. "1:1.0" refers to the mixing molar ratio, which is relative to the cerium peroxide material P-CeO x -1:0.5 or cerium oxide material P-CeO x -1:1.5 has the best antimony (III) removal effect, and can achieve an antimony (III) removal rate of up to 97.6% within 80 minutes.

[0039] Preferably, in step (2), the concentration of the cerium nitrate solution is 0.080 mol / L.

[0040] A cerium peroxide material for removing antimony (III) is prepared by a preparation method of a cerium peroxide material for removing antimony (III) according to any of the above embodiments, and has a pore structure distributed on the surface.

[0041] According to the above-mentioned preparation method, this scheme can prepare a cerium peroxide material with a rich porous structure on the surface. On the one hand, the preparation method is simple and does not require additional preparation into a microsphere structure, but the cerium peroxide material can be directly synthesized, which simplifies the preparation process of the antimony (III) removal material; on the other hand, the cerium peroxide material has a removal rate of antimony (III) as high as 97.6%, which solves the problem that the existing antimony (III) removal materials cannot have both high efficiency and ease of preparation.

[0042] A use of a cerium peroxide material in preparing an antimony (III) removal material, wherein the cerium peroxide material is a cerium peroxide material for removing antimony (III) according to any of the above embodiments.

[0043] A cerium peroxide material is used in oxidation to remove antimony (III). The cerium peroxide material is a cerium peroxide material for removing antimony (III) according to any of the above embodiments.

[0044] Embodiment 1:

[0045] A method for preparing a cerium peroxide material for removing antimony (III), comprising the following steps:

[0046] (1) Accurately measure 35.5 mL of concentrated ammonia water and dilute to 100 mL with deionized water to obtain 10% NH 3 Solution;

[0047] (2) accurately weighing 0.080 mol of cerium nitrate and dissolving it in 1000 mL of deionized water to obtain a cerium nitrate solution with a concentration of 0.080 mol / L after the solution is evenly dissolved;

[0048] (3) The cerium nitrate solution was evenly divided into solution A and solution B. Solution A was not treated, and 4 mL of 30% hydrogen peroxide was added to solution B. The two solutions were stirred for 30 min respectively.

[0049] (4) Use 10% NH 3 The solution A and solution B obtained in step (3) were adjusted to pH = 7.0, and stirred for 1 hour to obtain suspensions corresponding to solution A and solution B respectively;

[0050] (5) The suspension was rinsed with deionized water several times, freeze-dried, and ground through a 200-mesh sieve. Solution A corresponded to cerium oxide (CeO 2 ), solution B corresponds to the cerium oxide material (P-CeO x-1:1.0).

[0051] Put cerium oxide (CeO 2 ) and cerium peroxide material (P-CeO x -1:1.0) in an electron microscope to observe the surface structure, and compare the SEM images of the two. The SEM image corresponding to cerium oxide (CeO 2 ) is as shown in Figure 2 , and the SEM image corresponding to cerium peroxide material (P-CeO x -1:1.0) is as shown in Figure 1 .

[0052] Note:

[0053] From the comparison between Figure 1 and Figure 2 , it can be seen that compared with cerium oxide, the cerium peroxide material has a rich pore structure, and nano-small particles are evenly distributed on the stacked thin flakes. Its specific surface area is relatively large, which is beneficial to the removal of pollutants in terms of structure.

[0054] Example 2:

[0055] In order to explore the removal effect of cerium peroxide prepared with different Ce to hydrogen peroxide molar ratios on antimony (III), cerium peroxides with different Ce to hydrogen peroxide molar ratios were prepared, and an antimony (III) solution was used as simulated wastewater for testing.

[0056] (S1): The preparation of cerium oxide (CeO 2 ) and cerium peroxide (P-CeO x -1:1.0) is as in Example 1; The basic steps of cerium peroxide reference 1 (P-CeO x -1:0.5) and cerium peroxide reference 2 (P-CeO x -1:1.5) prepared in Example 2 are basically the same as those of the cerium peroxide in Example 1, except that:

[0057] For cerium peroxide reference 1, 2 ml of 30% hydrogen peroxide was added to cerium peroxide reference 1 in step (3);

[0058] For cerium peroxide reference 2, 6 ml of 30% hydrogen peroxide was added to cerium peroxide reference 1 in step (3);

[0059] (S2): Accurately weigh 2.409 g of antimony trioxide, dissolve it with concentrated hydrochloric acid, and dilute it to 1000 mL with deionized water to obtain a 1000 mg / L antimony (III) stock solution, and dilute it to obtain a 10 mg·L -1 antimony (III) solution;

[0060] (S3): Accurately weigh multiple portions of 0.0050 g of cerium oxide and cerium peroxide materials (P-CeO x -1:1.0), cerium peroxide reference 1 (P-CeO x -1:0.5), or cerium peroxide reference 2 (P-CeO x -1:1.5) and place them in 50 ml centrifuge tubes respectively. Pipette 25 mL of 10 mg·L -1 antimony(III) solution into each centrifuge tube. After mixing well, place them on a water bath shaker at 30 ± 1 °C and shake. At the shaking times of 1 min, 5 min, 10 min, 20 min, 40 min, 60 min, and 80 min, take the solution and filter it through a 0.45 μm filter membrane, and determine the concentration of Sb in the solution by inductively coupled plasma atomic emission spectrometry (ICP). The test results are as Figure 3 shown.

[0061] Note:

[0062] It Figure 3 can x be seen that for cerium peroxide reference 1 (P-CeO x -1:0.5) or cerium peroxide reference 2 (P-CeO 2 -1:1.5), the removal effect on antimony(III) is better than that of CeO x -1:1.0. Cerium peroxide reference 1 adds 2 ml less of 30% hydrogen peroxide than P-CeO x -1:1.0, and cerium peroxide reference 2 adds 2 ml more of 30% hydrogen peroxide than P-CeO x -1:1.0. However, the cerium peroxide material (P-CeO -1 -1:1.0) has the best removal effect on antimony(III), can reach the adsorption equilibrium within 80 min, and the equilibrium adsorption capacity is 48.8 mg·g x , and the removal rate is as high as 97.6%. It shows that the cerium peroxide material (P-CeO

[0063] -1:1.0) prepared by mixing cerium nitrate solution and hydrogen peroxide with a molar ratio of 1:1 has the most efficient removal effect on antimony(III).

[0064] Example 3:

[0065] (S1) Cerium oxide (CeO 2 ) and cerium peroxide material (P-CeO x-1:1.0) was prepared as in Case 1; cerium oxide (CeO 2 ), and peroxycerium (P-CeO x -1:1.0) was prepared as in Example 1; the peroxycerium reference 1 (P-CeO x -1:0.5) and peroxycerium reference 2 (P-CeO x -1:1.5) had basically the same basic steps as the peroxycerium in Example 1, with the only difference being that:

[0066] For peroxycerium reference 1, 2 mL of 30% hydrogen peroxide was added to peroxycerium reference 1 in step (3);

[0067] For peroxycerium reference 2, 6 mL of 30% hydrogen peroxide was added to peroxycerium reference 1 in step (3);

[0068] (S2) Accurately weigh 2.409 g of antimony trioxide, dissolve it with concentrated hydrochloric acid, and dilute it to 1000 mL with deionized water to obtain a 1000 mg / L antimony(III) stock solution, and obtain a 10 mg·L -1 antimony(III) solution by dilution;

[0069] (S3) Accurately weigh multiple portions of 0.0050 g of cerium oxide, peroxycerium material (P-CeO x -1:1.0), peroxycerium reference 1 (P-CeO x -1:0.5) or peroxycerium reference 2 (P-CeO x -1:1.5) and place them in 50 mL centrifuge tubes respectively. Pipette 25 mL of the 10 mg·L -1 antimony(III) solution into each centrifuge tube. After mixing well, place them on a water bath shaker at 30 ± 1 °C and shake. At 12 min, 24 min, 36 min, 60 min, 72 min, and 84 min of the shaking time, take 1 mL of the reaction suspension, add 4 mL of 6 mol / L hydrochloric acid solution to dissolve it, and test the concentrations of antimony(III) and total antimony in the dissolved solution by an atomic fluorescence spectrometer, and then calculate the oxidation rate of antimony(III). The results are as Figure 4 shown.

[0070] Note:

[0071] As Figure 4 can be seen, CeO 2 can oxidize 52% of antimony(III) in 84 min; the peroxycerium material (P-CeO x -1:1.0), peroxycerium reference 1 (P-CeO x -1:0.5) and peroxycerium reference 2 (P-CeOx -1:1.5), the oxidation rates of all three are higher than that of CeO 2 ; and after 84 min, the oxidation rates of cerium peroxide material (P-CeO x -1:1.0) and cerium peroxide contrast 2 (P-CeO x -1:1.5) for antimony(III) are better, both being 85%. It shows that the oxidation process of antimony(III) contributes to the removal of antimony.

[0072] Example 4:

[0073] In order to explore the mechanism of cerium oxide and cerium peroxide in oxidizing antimony(III), the following uses antimony(III) solution as simulated wastewater for testing to measure the free radicals generated in the reaction system.

[0074] The tests include: accurately weighing multiple portions of 0.0050 g of cerium oxide (CeO 2 ) or cerium peroxide material (P-CeO x -1:1) and placing them in 50 ml centrifuge tubes respectively. Then, transfer 25 mL of antimony(III) solution with a concentration of 10 mg·L -1 into each centrifuge tube to construct the following experimental systems:

[0075] ① CeO 2 + 10 mg·L -1 antimony(III) solution;

[0076] ② CeO 2 + 1 mM H 2 O 2 + 10 mg·L -1 antimony(III) solution;

[0077] ③ P-CeO x -1:1 + 10 mg·L -1 antimony(III) solution;

[0078] After fully mixing and reacting for 10 min, electron paramagnetic resonance spectroscopy analysis is carried out to measure the free radicals generated in the system. The results are as shown in Figure 5 and Figure 6 , where Figure 5 is the electron spin spectrum diagram substituting for hydroxyl free radicals, and Figure 6 is the electron spin spectrum diagram substituting for superoxide free radicals.

[0079] Note:

[0080] From Figure 5 and Figure 6 , it can be seen that CeO 2During the reaction with antimony(III), a small amount of hydroxyl radicals and superoxide radicals are generated, causing part of the antimony(III) to be oxidized to antimony(V). When 1 mM H 2 is added to the reaction system of antimony(III), 2 more hydroxyl radicals and superoxide radicals will be produced. Among the reactions of cerium peroxide materials (P-CeO 2 -1:1) with antimony(III), the most hydroxyl radicals and superoxide radicals are generated. This is also the main reason why cerium peroxide can oxidize most of the antimony(III), indicating that the peroxide group in cerium peroxide plays an important role in the oxidation reaction of antimony(III). x

[0081] Example 5:

[0082] To explore and compare the relationship between cerium oxide and cerium peroxide materials (P-CeO x -1:1) in treating wastewater contaminated with heavy metal antimony and the concentration of antimony in the wastewater. The following uses antimony(III) solution as simulated wastewater for testing.

[0083] The tests include: accurately weighing multiple portions of 0.0050 g of cerium oxide or cerium peroxide materials (P-CeO x -1:1) prepared in Example 1 and placing them in 50 ml centrifuge tubes respectively. Then, transfer 25 mL of antimony(III) solutions with concentrations of 20 mgL -1 , 30 mgL -1 , 40 mgL -1 , 50 mgL -1 , 60 mgL -1 and 70 mgL -1 into the centrifuge tubes respectively. After mixing well, place them on a water bath oscillator at 20 ± 1 °C (293 K), 30 ± 1 °C (303 K) and 40 ± 1 °C (313 K) respectively and shake. When the shaking time is 80 min, filter the solution through a 0.45 μm filter membrane, and determine the concentration of Sb in the solution by inductively coupled plasma atomic emission spectrometry (ICP). The test results are as shown in Figure 7 and Figure 8 .

[0084] Figure 7 is the isothermal adsorption curve of cerium oxide for antimony(III); Figure 8 is the isothermal adsorption curve of the cerium peroxide material (P-CeO x -1:1) for efficient oxidation and removal of antimony pollution for antimony(III). It can be seen from Figure 7 and Figure 8 that at 30 ± 1 °C (303 K), cerium oxide (CeO 2 ​) and cerium peroxide material (P-CeO x -1:1) The maximum adsorption capacities for antimony(III) are 102.2 and 235.2 mg·g -1 , indicating the high adsorption efficiency of this cerium peroxide material (P-CeO x -1:1) for antimony(III). Cerium oxide (CeO 2 ) and cerium peroxide material (P-CeO x -1:1) The adsorption capacity for antimony(III) increases with the increase of reaction temperature, indicating that the reaction process is an endothermic process.

[0085] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent shall be subject to the appended claims.

Claims

1. An application of cerium peroxide material in oxidation and removal of antimony III, characterized in that: The preparation method of the cerium peroxide material comprises the following steps: (1) dissolving cerium nitrate in deionized water to obtain a cerium nitrate solution with a concentration of 0.01 to 0.15 mol / L after the solution is evenly dissolved; (2) adding 20-40% hydrogen peroxide to the cerium nitrate solution of step (1) in a molar ratio of 1:(0.5-1.5), and stirring; (3) adjusting the pH of the solution obtained in step (2) to 7.0 with 5-15% NH3 solution, stirring, and obtaining a suspension; (4) Rinse the suspension with deionized water several times, freeze-dry and grind, and pass through a 100-300 mesh sieve to obtain cerium peroxide material P-CeO x .

2. The use of a cerium peroxide material in oxidation and removal of antimony III according to claim 1, characterized in that: In the step (2), the mixing molar ratio of the cerium nitrate solution and hydrogen peroxide is 1:1; In the step (4), the cerium oxide material P-CeO x -1:1.

0.

3. The use of a cerium peroxide material in oxidation and removal of antimony III according to claim 2, characterized in that: In the step (2), the concentration of the cerium nitrate solution is 0.080 mol / L.

4. Application of a cerium peroxide material according to any one of claims 1 to 3 in oxidation and removal of antimony III, characterized in that: The surface of the cerium peroxide material is distributed with pore structures.

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