Manganese oxide loaded ion type rare earth tailing adsorbent, preparation method thereof and application of adsorbing ammonia nitrogen

Abstract

The application provides a manganese oxide loaded ion type rare earth tailing adsorbent, a preparation method thereof and application of the adsorbent in ammonia nitrogen adsorption, and the manganese oxide loaded ion type rare earth tailing adsorbent comprises: an ion type rare earth tailing component with a particle size of less than 200 mesh as a carrier, and the carrier is loaded with manganese oxide; and the manganese oxide loaded ion type rare earth tailing adsorbent is applied to removal of ammonia nitrogen in wastewater. The adsorbent provided by the application utilizes solid waste of the rare earth tailing, utilizes the adsorption capacity of the manganese oxide loading on the ammonia nitrogen cation, improves the dispersity of the manganese oxide, improves the adsorption performance of the adsorbent, and is environment-friendly and convenient for desorption regeneration.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, and relates to an adsorbent, particularly to a manganese oxide-supported ion-type rare earth tailings adsorbent, its preparation method, and its application in adsorbing ammonia nitrogen. Background Technology

[0002] Rare earth elements are an important class of non-ferrous metal mineral resources. The mining of ion-adsorption rare earth deposits has employed three generations of different technologies: pond leaching, heap leaching, and in-situ leaching. Because ion-adsorption rare earth mines have long used ammonium sulfate in-situ leaching followed by ammonium carbonate precipitation for impurity removal, residual ammonium sulfate in the ore deposit undergoes seepage and migration after in-situ leaching, resulting in ammonia nitrogen entering the water bodies. Studies have found that even after dilution by groundwater and surface water, the concentration of leaching agent retained in the ore body still reaches 110 mg / L in spring and 90-160 mg / L in winter, far exceeding wastewater discharge standards. Therefore, there is an urgent need to develop effective methods for the deep treatment of ion-adsorption rare earth wastewater, specifically for the enrichment and recovery of ammonia nitrogen.

[0003] Traditional methods for treating rare earth mine wastewater mainly include chemical precipitation, solvent extraction, ion exchange, membrane separation, and adsorption. These methods play an important role in rare earth wastewater treatment. Among them, adsorption has a significant removal effect on pollutants that are difficult to degrade, and has many advantages such as strong selectivity, good adsorption effect, low energy consumption, simple operation, and cheap and readily available raw materials.

[0004] Rare earth tailings contain various clay minerals, including kaolinite, mica, montmorillonite, and illite, which possess certain adsorption properties. For example, CN110142021A discloses an ammonia nitrogen adsorbent based on a metakaolin-based polymer, its preparation method, and its application. This adsorbent is prepared by calcining a mixture of metakaolin, sodium hydroxide, and water glass. CN115608319A discloses a modified vermiculite adsorbent for removing ammonia nitrogen from water, along with its preparation and regeneration methods. This adsorbent is obtained by modifying the surface and pore structure of natural vermiculite with sodium chloride solution. These adsorbents modify clay minerals to achieve ammonia nitrogen adsorption, demonstrating the significant potential of clay minerals in ammonia nitrogen adsorption.

[0005] Manganese oxide possesses a large specific surface area, high redox potential, and negative surface charge, resulting in a high electrostatic adsorption capacity for cationic pollutants. Furthermore, manganese oxide is low in cost and environmentally friendly, making it a promising candidate for adsorption applications. However, the high surface energy of manganese oxide facilitates the formation of aggregates, which significantly reduces its specific surface area, electronegativity, and redox potential, thus limiting its adsorption performance.

[0006] Therefore, there is a need to provide a manganese oxide-loaded ionic rare earth tailings adsorbent to improve manganese oxide dispersion and loading, enhance ammonia nitrogen adsorption performance, and realize the solid waste utilization of ionic rare earth tailings. Summary of the Invention

[0007] The purpose of this invention is to provide a manganese oxide-supported ionic rare earth tailings adsorbent, its preparation method, and its application in adsorbing ammonia nitrogen, thereby utilizing ionic rare earth tailings as solid waste and improving the adsorption performance of ammonia nitrogen.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a manganese oxide-supported ionic rare earth tailings adsorbent, the manganese oxide-supported ionic rare earth tailings adsorbent comprising: using ionic rare earth tailings components with a particle size of less than 200 mesh as a carrier, and loading manganese oxide.

[0010] The adsorbent provided by this invention uses ionic rare earth tailings as a carrier, and utilizes its certain adsorption properties to reuse the rare earth tailings after leaching as solid waste, thereby removing manganese oxides (MnO4). x Loaded on a carrier, manganese oxide has a large surface area, high redox potential, and negative surface charge, giving it a high electrostatic adsorption capacity for cationic pollutants. The large surface area of ​​the carrier disperses manganese oxide particles and provides reaction space, preventing particle aggregation and enhancing its adsorption performance. Furthermore, it is stable, environmentally friendly, and can be desorbed and regenerated.

[0011] Preferably, the manganese oxide loading in the manganese oxide-supported ionic rare earth tailings adsorbent is 15-22%, for example, it can be 15%, 16%, 17%, 18%, 19%, 20%, 21% or 22%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0012] Preferably, the composition of the ion-adsorption rare earth tailings with a particle size of less than 200 mesh includes: 70-80 wt% kaolin and 20-30 wt% quartz and potassium feldspar.

[0013] Preferably, the composition of the ion-adsorption rare earth tailings includes: 30-40 wt% kaolinite and 60-70 wt% quartz and potassium feldspar.

[0014] Preferably, the ionic rare earth tailings include tailings after leaching with sodium salts and / or magnesium salts.

[0015] Secondly, the present invention provides a method for preparing the manganese oxide-supported ion-type rare earth tailings adsorbent described in the first aspect, the preparation method comprising the following steps:

[0016] The components with a particle size of less than 200 mesh in the ion-adsorption rare earth tailings were selected as mineral samples. The mineral samples were mixed with potassium permanganate solution and hydrogen peroxide solution, aged and separated to obtain the adsorbent.

[0017] Preferably, the concentration of the potassium permanganate solution is 0.3-0.5 mol / L, for example, it can be 0.3 mol / L, 0.35 mol / L, 0.4 mol / L, 0.45 mol / L or 0.5 mol / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0018] Preferably, the solid-liquid ratio of the mineral sample to the potassium permanganate solution is 1:(8-16)g / mL, for example, it can be 1:8g / mL, 1:10g / mL, 1:12g / mL, 1:14g / mL or 1:16g / mL, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0019] Preferably, the solid-liquid ratio of the mineral sample to the hydrogen peroxide solution is 1:(3-6)g / mL, for example, it can be 1:3g / mL, 1:4g / mL, 1:5g / mL or 1:6g / mL, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0020] Preferably, the mixing time is 20-60 minutes, for example, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes, but not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0021] Preferably, the aging time is 1-4 hours, for example, it can be 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0022] Preferably, the aging temperature is 20-30℃, for example, it can be 20℃, 22℃, 24℃, 25℃, 26℃, 28℃ or 30℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0023] Thirdly, the present invention provides an application of the manganese oxide-supported ion-type rare earth tailings adsorbent as described in the first aspect for adsorbing ammonia nitrogen, wherein the method of application includes: mixing and stirring the manganese oxide-supported ion-type rare earth tailings adsorbent with wastewater for adsorption.

[0024] Preferably, the solid-liquid ratio of the manganese oxide-supported ion-type rare earth tailings adsorbent to the wastewater is 2-12 g / L, for example, it can be 2 g / L, 4 g / L, 5 g / L, 6 g / L, 8 g / L, 10 g / L or 12 g / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0025] Preferably, the stirring method includes magnetic stirring and / or oscillating stirring.

[0026] Preferably, the stirring speed is 150-300 r / min, for example, it can be 150 r / min, 180 r / min, 200 r / min, 220 r / min, 250 r / min, 280 r / min or 300 r / min, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0027] Preferably, the adsorption time is 1.5-3.5h, for example, it can be 1.5h, 2h, 2.5h, 3h or 3.5h, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0028] Preferably, the adsorption temperature is 25-35℃, for example, it can be 25℃, 26℃, 28℃, 30℃, 32℃, 34℃ or 35℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0029] Preferably, the ammonia nitrogen concentration of the wastewater is 10-160 mg / L, for example, it can be 10 mg / L, 20 mg / L, 40 mg / L, 50 mg / L, 60 mg / L, 80 mg / L, 100 mg / L, 120 mg / L, 140 mg / L, 150 mg / L or 160 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0030] Preferably, the pH of the wastewater is 3-10, for example, it can be 3, 4, 5, 6, 7, 8, 9 or 10, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0031] Preferably, the desorption method of the manganese oxide-supported ion-type rare earth tailings adsorbent is as follows: the manganese oxide-supported ion-type rare earth tailings adsorbent is desorbed using an acidic solution.

[0032] Preferably, the acidic solution includes any one or a combination of at least two of hydrochloric acid solution, sulfuric acid solution, or nitric acid solution. Typical but non-limiting combinations include a combination of hydrochloric acid solution and sulfuric acid solution, a combination of sulfuric acid solution and nitric acid solution, a combination of hydrochloric acid solution and nitric acid solution, or a combination of hydrochloric acid solution, sulfuric acid solution, and nitric acid solution.

[0033] Preferably, the concentration of the acid solution is 0.05-0.15 mol / L, for example, it can be 0.05 mol / L, 0.08 mol / L, 0.10 mol / L, 0.12 mol / L or 0.15 mol / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] The adsorbent provided by this invention utilizes ionic rare earth tailings for solid waste treatment. It leverages the adsorption capacity of manganese oxide for ammonia nitrogen cations, improves the dispersibility of manganese oxide, enhances the adsorption performance of the adsorbent, and is environmentally friendly and easy to desorb and regenerate. Attached Figure Description

[0036] Figure 1 This is the XRD pattern of ion-type rare earth tailings used in the example.

[0037] Figure 2 This is an SEM image of the mineral sample provided in Example 1.

[0038] Figure 3 This is a SEM image of the manganese oxide-supported ion-type rare earth tailings adsorbent provided in Example 1.

[0039] Figure 4 This is the EDS image of the mineral sample provided in Example 1.

[0040] Figure 5 This is the EDS diagram of the manganese oxide-supported ion-type rare earth tailings adsorbent provided in Example 1. Detailed Implementation

[0041] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0042] To clearly illustrate the technical solution of this invention, in a specific embodiment, the ion-type rare earth tailings used include the following components: kaolin, quartz, and potassium feldspar, and their XRD patterns are shown below. Figure 1 As shown.

[0043] Example 1

[0044] This embodiment provides a manganese oxide-supported ion-type rare earth tailings adsorbent, the preparation method of which includes the following steps:

[0045] (1) The particle size of the components with a particle size of less than 200 mesh was selected from the ion-adsorption rare earth tailings by screening method as mineral samples;

[0046] (2) Select 5g of mineral sample and add it to deionized water and stir. Then add 70mL of potassium permanganate solution with a concentration of 0.4mol / L, and add 30mL of 30% hydrogen peroxide solution while stirring. Stir for 40min, and after aging for 1.5h, manganese oxide loaded ion type rare earth tailings adsorbent is obtained.

[0047] In this embodiment, the manganese oxide loading in the manganese oxide-supported ion-type rare earth tailings adsorbent is 21%. In this embodiment, the SEM and EDS images of the ore sample after screening in step (1) are shown below. Figure 2 and Figure 4 As shown, before loading, the kaolin inside has a smooth surface and a distinct layered structure; the SEM and EDS images of the obtained manganese oxide-supported ion-type rare earth tailings adsorbent are shown below. Figure 3 and Figure 5 As shown, after manganese oxide loading, needle-like and fine needle-like fragments appear on the surface, which may be due to the formation of manganese oxide. At the same time, the surface roughness changes significantly, and significantly smaller pores and grooves are observed on the entire surface. It can be seen that the manganese oxide loading is successful and changes the surface properties, thereby improving its electronegativity and redox ability, and thus achieving the purpose of improving adsorption capacity.

[0048] Example 2

[0049] This embodiment provides a manganese oxide-supported ion-type rare earth tailings adsorbent, the preparation method of which includes the following steps:

[0050] (1) The particle size of the components with a particle size of less than 200 mesh was selected from the ion-adsorption rare earth tailings by screening method as mineral samples;

[0051] (2) 10g of mineral sample was added to deionized water and stirred. Then, 80mL of potassium permanganate solution with a concentration of 0.4mol / L was added. 30mL of 30% hydrogen peroxide solution was added while stirring. After stirring for 60min and aging for 2h, manganese oxide-loaded ion-type rare earth tailings adsorbent was obtained.

[0052] In this embodiment, the loading of manganese oxide in the manganese oxide-supported ionic rare earth tailings adsorbent is 22%.

[0053] Example 3

[0054] This embodiment provides a manganese oxide-supported ion-type rare earth tailings adsorbent, the preparation method of which includes the following steps:

[0055] (1) The particle size of the components with a particle size of less than 200 mesh was selected from the ion-adsorption rare earth tailings by screening method as mineral samples;

[0056] (2) 8g of mineral sample was added to deionized water and stirred. Then, 65mL of potassium permanganate solution with a concentration of 0.4mol / L was added. 30mL of 30% hydrogen peroxide solution was added while stirring. After stirring for 40min and aging for 2.5h, manganese oxide-loaded ion-type rare earth tailings adsorbent was obtained.

[0057] In this embodiment, the loading of manganese oxide in the manganese oxide-supported ionic rare earth tailings adsorbent is 21%.

[0058] Example 4

[0059] This embodiment provides a manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with Example 1, the stirring time in step (2) is controlled to be 60 min, and the rest is the same as in Example 1.

[0060] Comparative Example 1

[0061] This comparative example provides an ionic rare earth tailings adsorbent, wherein the ionic rare earth tailings adsorbent is untreated ionic rare earth tailings.

[0062] Comparative Example 2

[0063] This comparative example provides a manganese oxide-loaded ion-type rare earth tailings adsorbent. Compared with Example 1, step (1) screening is not performed, and the rest is the same as Example 1.

[0064] Application Example 1

[0065] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. The method employs the manganese oxide-supported ion-type rare earth tailings adsorbent provided in Example 1, and includes the following steps:

[0066] 0.2 g of manganese oxide-supported ion-type rare earth tailings adsorbent was mixed with 100 mL of ammonia nitrogen wastewater, wherein the ammonia nitrogen concentration in the wastewater was 20 ppm and the pH was 6. The adsorption was then carried out at 25 °C and stirred at 200 r / min for 2 h. After solid-liquid separation, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent was obtained.

[0067] In this application example, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent is desorbed using 0.1 mol / L hydrochloric acid, and the desorbed manganese oxide-supported ion-type rare earth tailings adsorbent is used to remove ammonia nitrogen from wastewater using the above method.

[0068] The ammonia nitrogen adsorption capacity of the manganese oxide-supported ionic rare earth tailings adsorbent in this application example and the ammonia nitrogen adsorption capacity of the desorbed manganese oxide-supported ionic rare earth tailings adsorbent are listed in Table 1.

[0069] Application Example 2

[0070] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. The method employs the manganese oxide-supported ion-type rare earth tailings adsorbent provided in Example 2, and includes:

[0071] 0.2g of manganese oxide-supported ion-type rare earth tailings adsorbent was mixed with 100mL of ammonia nitrogen wastewater, wherein the ammonia nitrogen concentration in the wastewater was 40ppm and the pH was 5. The adsorption was then carried out at 25℃ and 200r / min for 2h with stirring. After solid-liquid separation, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent was obtained.

[0072] In this application example, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent is desorbed using 0.09 mol / L hydrochloric acid, and the desorbed manganese oxide-supported ion-type rare earth tailings adsorbent is used to remove ammonia nitrogen from wastewater using the above method.

[0073] The ammonia nitrogen adsorption capacity of the manganese oxide-supported ionic rare earth tailings adsorbent in this application example and the ammonia nitrogen adsorption capacity of the desorbed manganese oxide-supported ionic rare earth tailings adsorbent are listed in Table 1.

[0074] Application Example 3

[0075] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. The method employs the manganese oxide-supported ion-type rare earth tailings adsorbent provided in Example 3, and includes:

[0076] 0.4 g of manganese oxide-supported ion-type rare earth tailings adsorbent was mixed with 100 mL of ammonia nitrogen wastewater, wherein the ammonia nitrogen concentration in the wastewater was 110 ppm and the pH was 7. The adsorption was then carried out at 25℃ and stirred at 250 r / min for 2 h. After solid-liquid separation, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent was obtained.

[0077] In this application example, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent is desorbed using 0.15 mol / L hydrochloric acid, and the desorbed manganese oxide-supported ion-type rare earth tailings adsorbent is used to remove ammonia nitrogen from wastewater using the above method.

[0078] The ammonia nitrogen adsorption capacity of the manganese oxide-supported ionic rare earth tailings adsorbent in this application example and the ammonia nitrogen adsorption capacity of the desorbed manganese oxide-supported ionic rare earth tailings adsorbent are listed in Table 1.

[0079] Application Example 4

[0080] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. The method employs the manganese oxide-supported ion-type rare earth tailings adsorbent provided in Example 2, and includes:

[0081] 0.8 g of manganese oxide-supported ion-type rare earth tailings adsorbent was mixed with 100 mL of ammonia nitrogen wastewater, wherein the ammonia nitrogen concentration in the wastewater was 40 ppm and the pH was 6. The adsorption was then carried out at 25 °C and stirred at 200 r / min for 2.5 h. After solid-liquid separation, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent was obtained.

[0082] In this application example, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent is desorbed using 0.09 mol / L hydrochloric acid, and the desorbed manganese oxide-supported ion-type rare earth tailings adsorbent is used to remove ammonia nitrogen from wastewater using the above method.

[0083] The ammonia nitrogen adsorption capacity of the manganese oxide-supported ionic rare earth tailings adsorbent in this application example and the ammonia nitrogen adsorption capacity of the desorbed manganese oxide-supported ionic rare earth tailings adsorbent are listed in Table 1.

[0084] Application Example 5

[0085] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. The method employs the manganese oxide-supported ion-type rare earth tailings adsorbent provided in Example 3, and includes:

[0086] 1g of manganese oxide-supported ion-type rare earth tailings adsorbent was mixed with 100mL of ammonia nitrogen wastewater, wherein the ammonia nitrogen concentration in the wastewater was 160ppm and the pH was 7. The adsorption was then carried out at 25℃ and stirred at 250r / min for 2h. After solid-liquid separation, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent was obtained.

[0087] In this application example, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent is desorbed using 0.15 mol / L hydrochloric acid, and the desorbed manganese oxide-supported ion-type rare earth tailings adsorbent is used to remove ammonia nitrogen from wastewater using the above method.

[0088] The ammonia nitrogen adsorption capacity of the manganese oxide-supported ionic rare earth tailings adsorbent in this application example and the ammonia nitrogen adsorption capacity of the desorbed manganese oxide-supported ionic rare earth tailings adsorbent are listed in Table 1.

[0089] Application Example 6

[0090] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with Application Example 1, the amount of manganese oxide-supported ion-type rare earth tailings adsorbent used is 0.4g, while the rest are the same as in Application Example 1.

[0091] Application Example 7

[0092] This application example provides a method for removing ammonia nitrogen from manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with application example 1, the adsorbed manganese oxide-supported ion-type rare earth tailings adsorbent is desorbed using 0.11 mol / L hydrochloric acid, while the rest is the same as application example 1.

[0093] Application Example 8

[0094] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with Application Example 1, the ammonia nitrogen concentration in the ammonia nitrogen wastewater is 160 ppm, while the rest are the same as in Application Example 1.

[0095] Application Example 9

[0096] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with application example 1, the manganese oxide-supported ion-type rare earth tailings adsorbent is replaced in equal amounts with the manganese oxide-supported ion-type rare earth tailings adsorbent provided in example 4, while the rest is the same as application example 1.

[0097] Application Example 10

[0098] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with Application Example 1, the pH of the ammonia nitrogen wastewater is 3, while the rest are the same as in Application Example 1.

[0099] Application Example 11

[0100] This application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with Application Example 1, the pH of the ammonia nitrogen wastewater is 10, while the rest are the same as in Application Example 1.

[0101] Comparative Application Example 1

[0102] This comparative application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with Application Example 1, the manganese oxide-supported ion-type rare earth tailings adsorbent is replaced in equal amounts with the manganese oxide-supported ion-type rare earth tailings adsorbent provided in Comparative Example 1, while all other aspects are the same as in Application Example 1.

[0103] Comparative Application Example 2

[0104] This comparative application example provides a method for removing ammonia nitrogen using a manganese oxide-supported ion-type rare earth tailings adsorbent. Compared with application example 1, the manganese oxide-supported ion-type rare earth tailings adsorbent is replaced in equal amounts with the manganese oxide-supported ion-type rare earth tailings adsorbent provided in comparative example 2, while all other aspects are the same as in application example 1.

[0105] In the application examples and comparative application examples, the ammonia nitrogen content in the wastewater before and after adsorption was determined by ultraviolet spectrophotometry, and the adsorption capacity (q, mg / g) and adsorption rate (η, %) of ammonia nitrogen were calculated. The results are listed below.

[0106] The calculation formulas in Table 1 are as follows:

[0107]

[0108]

[0109] Among them, C0 and C t The initial concentration of ammonia nitrogen and the concentration of ammonia nitrogen after a certain adsorption time are respectively represented; V is the volume of ammonia nitrogen wastewater; and m is the mass of the adsorbent.

[0110] Table 1

[0111]

[0112]

[0113] As shown in Table 1, the adsorbent provided by this invention can effectively adsorb ammonia nitrogen in wastewater, with an adsorption capacity of up to 10.25 mg / g. Furthermore, the adsorbent can be regenerated using hydrochloric acid, and its adsorption capacity can still reach 9.33 mg / g after regeneration. It exhibits good adsorption performance, facilitates the regeneration and utilization of the adsorbent, and realizes the utilization of rare earth tailings as solid waste. It is environmentally friendly and has high economic value.

[0114] In summary, the adsorbent provided by this invention utilizes rare earth tailings as solid waste, leverages the adsorption capacity of manganese oxide for ammonia nitrogen cations, improves the dispersibility of manganese oxide, enhances the adsorption performance of the adsorbent, and is environmentally friendly and easy to desorb and regenerate.

[0115] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. An application of a manganese oxide-supported ion-type rare earth tailings adsorbent for adsorbing ammonia nitrogen, characterized in that, The method of application includes: mixing and stirring manganese oxide-supported ionic rare earth tailings adsorbent with wastewater for adsorption; the manganese oxide-supported ionic rare earth tailings adsorbent includes: using ionic rare earth tailings components with a particle size of less than 200 mesh as a carrier, and loading manganese oxide; the composition of the ionic rare earth tailings with a particle size of less than 200 mesh includes: 70-80 wt% kaolinite, and 20-30 wt% quartz and potassium feldspar.

2. Use according to claim 1, characterized in that, The manganese oxide loading in the manganese oxide-supported ion-type rare earth tailings adsorbent is 15-22%.

3. Use according to claim 1, characterized in that, The ionic rare earth tailings include tailings after leaching with sodium salts and / or magnesium salts.

4. Use according to claim 1, characterized in that, The preparation method of the manganese oxide-supported ion-type rare earth tailings adsorbent includes the following steps: The components with a particle size of less than 200 mesh in the ion-adsorption rare earth tailings were selected as mineral samples. The mineral samples were mixed with potassium permanganate solution and hydrogen peroxide solution, aged and separated to obtain the adsorbent.

5. Use according to claim 4, characterized in that, The concentration of the potassium permanganate solution is 0.3-0.5 mol / L.

6. Use according to claim 4, characterized in that, The solid-liquid ratio of the mineral sample to the potassium permanganate solution was 1:(8-16)g / mL.

7. Use according to claim 4, characterized in that, The solid-liquid ratio of the mineral sample to the hydrogen peroxide solution was 1:(3-6)g / mL.

8. Use according to claim 4, characterized in that, The mixing time is 20-60 minutes.

9. Use according to claim 4, characterized in that, The aging time is 1-4 hours.

10. The use according to claim 1, characterized in that, The solid-liquid ratio of the manganese oxide-supported ion-type rare earth tailings adsorbent to the wastewater is 2-12 g / L.

11. Use according to claim 1, characterized in that, The stirring methods include magnetic stirring and / or oscillating stirring.

12. The use according to claim 1, characterized in that, The stirring speed is 150-300 r / min.

13. The use according to claim 1, characterized in that, The adsorption time is 1.5-3.5 hours.

14. The use according to claim 1, characterized in that, The adsorption temperature is 25-35℃.

15. The use according to claim 1, characterized in that, The ammonia nitrogen concentration in the wastewater is 10-160 mg / L.

16. The use according to claim 1, characterized in that, The pH of the wastewater is 3-10.

17. The application according to claim 1, characterized in that, The desorption method for the manganese oxide-supported ion-type rare earth tailings adsorbent is as follows: the manganese oxide-supported ion-type rare earth tailings adsorbent is desorbed using an acidic solution.

18. The use according to claim 17, characterized in that, The acidic solution includes any one or a combination of at least two of hydrochloric acid solution, sulfuric acid solution, or nitric acid solution.

19. The application according to claim 17, characterized in that, The concentration of the acidic solution is 0.05-0.15 mol / L.

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