Cerium peroxide material for removing antimony III, preparation method and application

Abstract

The invention discloses a cerium peroxide material for removing antimony III, and a preparation method and application thereof. The preparation method comprises the following steps: dissolving cerium nitrate into deionized water to obtain a cerium nitrate solution with the concentration of 0.01-0.15 mol / L; adding hydrogen peroxide into the cerium nitrate solution, wherein the mixing molar ratio of the cerium nitrate solution to the hydrogen peroxide is 1: (0.5-1.5); adjusting the pH value of the obtained solution to 7.0 by using a 5-15% NH3 solution to respectively obtain suspension liquids; and washing the suspension liquid for multiple times, performing freeze drying, grinding, and sieving with a 100-300-mesh sieve to obtain the cerium peroxide material P-CeOx. According to the scheme, a microsphere structure does not need to be additionally prepared, and the cerium peroxide material is directly synthesized, so that the preparation process of the antimony-removing III material is simplified; on the other hand, the antimony III removal rate of the cerium peroxide material is as high as 97.6%, and the problem that the high efficiency and the preparation convenience of the existing antimony III removal material cannot be simultaneously realized is solved.

Description

Technical Field

[0001] The invention relates to the field of pollution adsorption materials, and in particular to a cerium peroxide material for removing antimony III, a preparation method and application thereof. Background Art

[0002] Antimony (Sb) is an emerging toxic heavy metal pollutant. Antimony pollution in soil, sediment, water and biological systems poses potential health risks to humans and animals, which has attracted great attention. The U.S. 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 for antimony in drinking water is 20ug / L. The antimony concentration limit in China's "GB3838-2002 Surface Water Environmental Quality Standard" is 0.005mg / L. Sb in the environment 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 crops for antimony (III) is higher than that of antimony (V), and the toxicity of antimony (III) is higher than that of antimony (V). Antimony (III) pollution poses a serious threat to environmental safety, and economical and effective treatment technology is urgently needed. Existing materials for efficient oxidation removal of antimony (III) generally prepare a microsphere structure, adsorb antimony (III) through the microsphere structure, and then add antimony removal active ingredients to the microsphere structure; in this way, antimony removal requires both the preparation of the microsphere structure and the loading of the antimony removal active ingredients, resulting in a complex preparation method for antimony removal, high cost, and unstable antimony removal efficiency. Summary of the invention

[0003] The object of the present invention is to provide a method for preparing a cerium peroxide material for removing antimony III, which has both high antimony III removal efficiency and simple preparation.

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

[0005] A method for preparing a cerium peroxide material for removing antimony III comprises the following steps:

[0006] (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;

[0007] (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;

[0008] (3) Use 5-15% NH 3 The solution obtained in step (2) was adjusted to pH = 7.0, stirred, and suspensions were obtained respectively;

[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 is a kinetic curve diagram of the oxidation effect of cerium oxide and cerium peroxide prepared with different molar ratios of Ce to hydrogen peroxide on antimony (III) in Example 3;

[0022] Figure 5 is CeO in Example 4 2 The electron spin spectrum of a small amount of hydroxyl radicals produced during the reaction with antimony (III);

[0023] Figure 6 is CeO in Example 4 2 The electron spin spectrum of a small amount of superoxide radicals produced during the reaction with antimony (III);

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

[0025] Figure 8 The cerium oxide material (P-CeO x -1:1) isothermal adsorption curve of antimony (III). DETAILED DESCRIPTION

[0026] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0027] For ease of understanding of the present invention, the present invention is described more fully 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 of the present invention more thorough and comprehensive. If no specific technology or conditions are indicated in the embodiments, the technology or conditions described in the documents in this area or the product instructions are carried out. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products that can be obtained by commercial purchase.

[0028] A method for preparing a cerium peroxide material for removing antimony (III), comprising the following steps:

[0029] (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;

[0030] (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;

[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] Cerium oxide (CeO 2 ) and peroxide cerium materials (P-CeO x -1:1.0) was placed under an electron microscope to observe the surface structure and the SEM images of the two were compared. 2 ) The corresponding SEM images are shown in Figure 2 , cerium oxide material (P-CeO x -1:1.0) corresponding to the SEM picture Figure 1 .

[0052] illustrate:

[0053] Depend on Figure 1 and Figure 2 By comparison, compared with cerium oxide, cerium peroxide material has a rich pore structure, with small nanoparticles evenly distributed on the stacked layers of thin sheets. It has a large specific surface area and is structurally conducive to the removal of pollutants.

[0054] Embodiment 2:

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

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

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

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

[0059] (S2): Accurately weigh 2.409 g of antimony trioxide, dissolve it in concentrated hydrochloric acid, and then add deionized water to make up to 1000 mL to obtain a 1000 mg / L antimony (III) stock solution. Dilute it to obtain a 10 mg / L -1 Antimony (III) solution;

[0060] (S3): Accurately weigh several portions of 0.0050 g of cerium oxide and peroxide material (P-CeO x -1:1.0), cerium peroxide comparison 1 (P-CeO x -1:0.5) or cerium peroxide comparison 2 (P-CeO x -1:1.5) were placed in 50 ml centrifuge tubes, and 25 ml of 10 mg·L -1 The antimony (III) solution was mixed thoroughly and then placed on a 30±1°C water bath oscillator for shaking. When the shaking time was 1min, 5min, 10min, 20min, 40min, 60min and 80min, the solution was filtered through a 0.45μm filter membrane and the Sb concentration in the solution was determined by inductively coupled plasma atomic emission spectroscopy (ICP). The test results are as follows: Figure 3 shown.

[0061] illustrate:

[0062] Can Figure 3 It can be seen that for the cerium peroxide comparison material 1 (P-CeO x -1:0.5) or cerium peroxide comparison 2 (P-CeO x -1:1.5) has a better removal effect on antimony (III) than CeO 2 Good, cerium peroxide comparison 1 is better than P-CeO x -1:1.0 Add 2 ml less 30% hydrogen peroxide, cerium peroxide comparison 2 than P-CeO x -1:1.0Add 2 ml of 30% hydrogen peroxide, but the cerium peroxide material (P-CeO x -1:1.0) had the best removal effect on antimony (III), and the adsorption equilibrium could be reached within 80 min, with an equilibrium adsorption capacity of 48.8 mg·g -1 The removal rate is as high as 97.6%. x -1:1.0) In the preparation, the cerium peroxide material is prepared by mixing cerium nitrate solution and hydrogen peroxide in a mixing molar ratio of 1:1, which has the most efficient antimony (III) removal effect.

[0063] Embodiment 3:

[0064] In order to explore the oxidation effect of cerium peroxide prepared with different molar ratios of Ce to hydrogen peroxide on antimony (III), cerium peroxide with different molar ratios of Ce to hydrogen peroxide was prepared, and antimony (III) solution was used as simulated wastewater for testing.

[0065] (S1) Cerium Oxide (CeO 2 ) and peroxide cerium materials (P-CeO x-1:1.0) as in Case 1; cerium oxide (CeO 2 ) and cerium peroxide (P-CeO x -1:1.0) was prepared as in Example 1; the cerium peroxide comparison 1 (P-CeO x -1:0.5) and cerium peroxide comparison 2 (P-CeO x The basic steps of the cerium peroxide of Example 1 are basically the same, except that:

[0066] For cerium peroxide comparative substance 1, 2 ml of 30% hydrogen peroxide was added to cerium peroxide comparative substance 1 in step (3);

[0067] For cerium peroxide comparative substance 2, 6 ml of 30% hydrogen peroxide was added to cerium peroxide comparative substance 1 in step (3);

[0068] (S2) Accurately weigh 2.409 g of antimony trioxide, dissolve it in concentrated hydrochloric acid, and then add deionized water to make up to 1000 mL to obtain a 1000 mg / L antimony (III) stock solution. Dilute it to obtain a 10 mg / L -1 Antimony (III) solution;

[0069] (S3) Accurately weigh multiple portions of 0.0050 g of cerium oxide and cerium peroxide material (P-CeO x -1:1.0), cerium peroxide comparison 1 (P-CeO x -1:0.5) or cerium peroxide comparison 2 (P-CeO x -1:1.5) were placed in 50 ml centrifuge tubes, and 25 ml of 10 mg·L -1 The antimony (III) solution was fully mixed and then placed on a 30±1°C water bath oscillator for shaking. When the shaking time was 12min, 24min, 36min, 60min, 72min and 84min, 1mL of the reaction suspension was removed and 4mL of 6mol / L hydrochloric acid solution was added to dissolve it. The concentrations of antimony (III) and total antimony in the dissolved solution were tested by atomic fluorescence spectrophotometer, and the oxidation rate of antimony (III) was calculated. The results are as follows: Figure 4 shown.

[0070] illustrate:

[0071] Depend on Figure 4 It can be seen that CeO 2 It can oxidize 52% of antimony (III) in 84 min; the cerium peroxide material (P-CeO x -1:1.0), cerium peroxide comparison 1 (P-CeO x -1:0.5) and cerium peroxide comparison 2 (P-CeOx -1:1.5) The oxidation rates of the three are higher than CeO 2 high; while after 84min, the cerium oxide material (P-CeO x -1:1.0) and cerium peroxide comparison 2 (P-CeO x -1:1.5) had a good oxidation rate for antimony (III), both of which were 85%, indicating that the oxidation process of antimony (III) was helpful for the removal of antimony.

[0072] Embodiment 4:

[0073] In order to explore the mechanism of antimony (III) oxidation by cerium oxide and cerium peroxide, antimony (III) solution was used as simulated wastewater to test the free radicals generated by the reaction system.

[0074] The test includes: accurately weighing multiple portions of 0.0050g cerium oxide (CeO 2 ) or cerium oxide material (P-CeO x -1:1) were placed in 50 ml centrifuge tubes, and 25 ml of 10 mg·L -1 Antimony (III) solution, so as to construct the following experimental system:

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

[0076] ②CeO 2 +1mMH 2 O 2 +10mg·L -1 Antimony (III) solution;

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

[0078] After fully mixing and reacting for 10 minutes, electron paramagnetic resonance spectroscopy analysis was performed to test the free radicals generated by the system. The results were as follows: Figure 5 and Figure 6 As shown, Figure 5 To replace the electron spin spectrum of hydroxyl radicals, Figure 6 The electron spin spectrum of superoxide radicals.

[0079] illustrate:

[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, so that part of antimony (III) is oxidized to antimony (V). 2 Add 1mM H2O to the reaction system with antimony (III) 2 O 2 , more hydroxyl radicals and superoxide radicals will be generated. x The hydroxyl radicals and superoxide radicals produced in the reaction of cerium peroxide with antimony (III) are the largest, which is the main reason why cerium peroxide can oxidize most of antimony (III). It also shows that the peroxide in cerium peroxide plays an important role in the oxidation reaction of antimony (III).

[0081] Embodiment 5:

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

[0083] The test includes: accurately weighing multiple portions of 0.0050g of cerium oxide or peroxide cerium material (P-CeO x -1:1) were placed in 50ml centrifuge tubes, and 25mL of 20mgL -1 , 30mgL -1 , 40mgL -1 , 50mgL -1 , 60mgL -1 and 70mgL -1 The antimony (III) solution was fully mixed and then placed on a water bath oscillator at 20±1℃ (293K), 30±1℃ (303K) and 40±1℃ (313K) for oscillation. When the oscillation time was 80min, the solution was filtered through a 0.45μm filter membrane and the Sb concentration in the solution was determined by inductively coupled plasma atomic emission spectroscopy (ICP). The test results are as follows: Figure 7 and Figure 8 shown.

[0084] Figure 7 is an isothermal adsorption curve of antimony (III) by the cerium oxide; Figure 8 The cerium oxide material (P-CeO x -1:1) isothermal adsorption curve of antimony (III). Figure 7 and Figure 8 It can be seen that at 30±1℃(303K), cerium oxide (CeO 2) and peroxide cerium materials (P-CeO x -1:1) for antimony (III) are 102.2 and 235.2 mg·g -1 , which illustrates the cerium oxide material (P-CeO x -1:1) has high adsorption capacity for antimony (III). 2 ) and peroxide cerium materials (P-CeO x -1:1) increases with the reaction temperature, indicating that the reaction is an endothermic process.

[0085] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing a cerium peroxide material for removing antimony III, characterized in that: The following steps are involved: (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 suspensions; (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 .

2. The method for preparing a cerium peroxide material for removing 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 method for preparing a cerium peroxide material for removing 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. A cerium peroxide material for removing antimony III, characterized in that: The cerium peroxide material is prepared by the preparation method for removing antimony III as described in any one of claims 1 to 3, and has a porous structure distributed on the surface.

5. Use of a cerium peroxide material in the preparation of an antimony III removal material, characterized in that: The cerium peroxide material is the cerium peroxide material for removing antimony III as described in claim 4.

6. Application of a cerium peroxide material in oxidation and removal of antimony III, characterized in that: The cerium peroxide material is the cerium peroxide material for removing antimony III as described in claim 4.

Images