Preparation and application of vanadium efficient adsorption-reduction material prepared by flash joule heating with red mud and pyrite as raw materials
The metallic vanadium adsorbent material prepared by flash evaporation and Joule heating solves the problems of high cost and oxidation of zero-valent iron, achieving efficient vanadium pollution removal and is suitable for waste treatment in vanadium application fields.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINESE RES ACAD OF ENVIRONMENTAL SCI
- Filing Date
- 2025-12-22
- Publication Date
- 2026-06-12
Smart Images
Figure CN121588765B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of adsorption materials, and relates to the preparation and application of a highly efficient adsorption-reduction material for metallic vanadium prepared by flash evaporation and Joule heating using red mud and pyrite as raw materials. Background Technology
[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.
[0003] Vanadium (symbol V) is a silvery-white, bright metal with a hard texture. Its compounds are widely used in industrial production. For example, as a "performance multiplier" in the steel industry, the addition of trace amounts of vanadium can increase the strength of steel by more than 40% while maintaining good toughness, enabling the development of structural materials for extreme environments such as high-speed rail tracks and deep-sea drilling platforms. In the wave of the energy revolution, vanadium redox flow batteries, with their ultra-long cycle life of over 20 years and inherent safety, are becoming the preferred solution for grid-scale energy storage. More notably, titanium-vanadium alloys have made groundbreaking applications in the aerospace field—15% of the titanium alloy components in the Boeing 787 fuselage structure incorporate vanadium, allowing it to withstand extreme temperature differences from -55°C to 300°C while reducing weight by 30%. This cross-industry value of this "industrial vitamin" is driving the global vanadium market to expand at an average annual rate of 8.2%.
[0004] However, the problem of vanadium pollution has increasingly attracted people's attention. For example, vanadium pentoxide (V2O5) is a highly toxic substance. After entering the environment through atmospheric deposition or water discharge, it can lead to soil acidification, water eutrophication, and accumulation along the food chain, causing lasting damage to the ecosystem.
[0005] Therefore, some studies have used sulfide amorphous zero-valent iron (mZVI) to prepare uniformly distributed FeS. x While vanadium can be removed using a shell-like adsorbent, the high cost of commercially available zero-valent iron limits its application. Therefore, there is an urgent need to develop lower-cost, solid waste-based vanadium adsorbents to achieve resource utilization of solid waste and reduce production costs. Summary of the Invention
[0006] To address the aforementioned problems, this invention provides a method for preparing and applying a highly efficient vanadium adsorption-reduction material using red mud and pyrite as raw materials via flash evaporation and Joule heating. The raw material prepared by this invention via flash evaporation and Joule heating exhibits a higher specific surface area and a significantly increased number of pentavalent vanadium reduction adsorption sites, effectively improving the adsorption efficiency for vanadium.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] The first aspect of this invention provides a method for preparing a highly efficient adsorption-reduction material of metallic vanadium using red mud and pyrite as raw materials by flash evaporation and Joule heating, comprising:
[0009] The red mud was washed with water until the pH value of the washing solution stabilized at a slightly alkaline level. The mixture was then dehydrated and dried to obtain dealkalized red mud.
[0010] The dealkali-treated red mud and pyrite powder were mixed evenly in water at a preset temperature. The mixture was then dehydrated and dried to obtain a red mud-pyrite mixed sample.
[0011] The red mud and pyrite mixture sample was mixed evenly with carbon black to obtain a mixture;
[0012] The mixture was subjected to flash Joule heating to obtain a high-efficiency adsorption-reduction raw material for metallic vanadium.
[0013] In a second aspect, the present invention provides the method described above for preparing highly efficient adsorption-reduction raw materials for metallic vanadium.
[0014] A third aspect of the present invention provides the application of the above-mentioned high-efficiency adsorption-reduction material of vanadium metal in the adsorption of heavy metals, wherein the heavy metals include vanadium.
[0015] Beneficial effects of the present invention
[0016] (1) This invention provides a method for preparing and applying a highly efficient adsorption-reduction material for metallic vanadium prepared from red mud and pyrite using flash Joule heating. Flash Joule heating of the raw materials results in high efficiency in reducing zero-valent iron, and the zero-valent iron is not easily oxidized again during this process. This leads to a high content of zero-valent iron in the material, resulting in a large number of reduction adsorption sites and a significantly better initial vanadium adsorption capacity than other materials. This material can be applied to scenarios such as the harmless disposal of waste or emergency treatment of vanadium pollution in the vanadium application field, and has good practical application prospects.
[0017] (2) Compared with zero-valent iron materials, the introduction of ferrous sulfide enables the material to maintain its reduction and adsorption capacity in weakly acidic and neutral environments.
[0018] (3) Zero-valent iron is the main source of the reducing power of materials. In traditional furnaces, the efficiency of heat treatment is primarily limited by the physical bottleneck of heat conduction. This deficiency leads to the generation of zero-valent iron (Fe2O3) through the reduction of Fe2O3. 0 Rapid re-oxidation occurs within minutes, forming a dense iron oxide film on the particle surface. The presence of this passivation layer severely hinders the diffusion and migration of reactants into the interior and the transfer of electrons to the outside, ultimately significantly weakening the Fe... 0The chemical reactivity of flash Joule heating, through the dual effects of its extreme high-temperature transient electric pulse, can effectively break the chemical bonds of iron-containing precursors in red mud, converting them into Fe. 0 and Fe² + It incorporates iron species with reducing activity and constructs a synergistic heterojunction interface structure. Furthermore, the ultra-rapid heating-cooling cycle unique to flash Joule heating not only effectively inhibits the secondary oxidation of zero-valent iron but also significantly suppresses the aggregation of iron components, thereby forming highly dispersed and uniformly distributed metal active centers in the material, thus effectively improving the material's adsorption performance.
[0019] (4) The preparation method of the present invention is simple, practical and easy to promote. Attached Figure Description
[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. Exemplary embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.
[0021] Figure 1 This is a photograph of the adsorbent material prepared in Example 2 of the present invention;
[0022] Figure 2 This is a diagram of the flash joule heating device of the present invention. Detailed Implementation
[0023] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of skill in the art. The reagents and raw materials used in this invention are readily available through conventional means, and unless otherwise specified, they are used in accordance with conventional methods in the art or product instructions. Similarly, unless otherwise specified, the test methods of this invention are performed in accordance with conventional methods in the art or industry-standard methods or practices. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to the methods of this invention. The preferred embodiments and materials described herein are for illustrative purposes only.
[0025] This invention provides a method for preparing a highly efficient adsorption-reduction material of metallic vanadium using red mud and pyrite as raw materials via flash evaporation and Joule heating, comprising:
[0026] The red mud was washed with water until the pH value of the washing solution stabilized at a slightly alkaline level. The mixture was then dehydrated and dried to obtain dealkalized red mud.
[0027] The dealkali-treated red mud and pyrite powder were mixed evenly in water at a preset temperature. The mixture was then dehydrated and dried to obtain a red mud-pyrite mixed sample.
[0028] The red mud and pyrite mixture sample was mixed evenly with carbon black to obtain a mixture;
[0029] The mixture was subjected to flash Joule heating to obtain a high-efficiency adsorption-reduction raw material for metallic vanadium.
[0030] This invention involves washing and dealkalizing red mud to remove soluble alkali, avoiding the formation of melts during heating that could cover active sites. Preferably, the method for preparing dealkalized red mud includes: mixing red mud with water and stirring at 50℃-60℃ for 1-2 hours, dehydrating, collecting the solid product and washing liquid separately, and repeating the washing and dehydration process on the solid product until the pH of the washing liquid stabilizes within the range of 9-10 to achieve a better dealkalization effect.
[0031] It should be noted that when the pH of the red mud washing solution is 9-10, it proves that most of the soluble alkali in the material has been removed. Avoid generating melts during heating, as these can cover the active sites of the material and affect its performance.
[0032] In some embodiments, the mass ratio of the dealkalized red mud to pyrite is 2:3-4. This invention mixes the dealkalized red mud and pyrite in water to ensure uniform mixing of the raw materials, avoid localized overheating during heating, and guarantee that the reduction and sulfidation reactions in the FJH process occur simultaneously. This results in an increased and more uniform distribution of zero-valent iron in the material, and effective sulfidation.
[0033] In some embodiments, the preset temperature is 50°C-60°C;
[0034] In some embodiments, the weakly alkaline pH range is 9-10.
[0035] In some embodiments, the mass ratio of the red mud-pyrite mixture sample to carbon black is 9:1-1.5.
[0036] It should be noted that the mixture needs to be dehydrated and dried before flash joule heating to ensure the effectiveness of flash joule heating.
[0037] In some embodiments, the flash Joule heating is carried out under an inert atmosphere, which is argon.
[0038] In some embodiments, the voltage of the flash Joule heating is 60V-80V. When the material temperature reaches 1300℃-1400℃, the heating is stopped, the temperature is maintained for 5-10 minutes, and then cooled to room temperature.
[0039] In some embodiments, the particle size of the dealkalized red mud is 80-100 micrometers.
[0040] The present invention will be further described in detail below with reference to specific embodiments. It should be noted that the specific embodiments are explanations of the present invention and not limitations thereof.
[0041] Example 1
[0042] First, crushing and grinding: crush and grind the red mud into powder with a particle size of 80-100 micrometers, and then put it into a drying oven and dry it at 80 degrees Celsius for 12 hours.
[0043] Second, dealkali removal treatment: The ground red mud sample is mixed with pure water at a ratio of 1:10 and placed in a stirrer, heated to 50 degrees Celsius, and stirred continuously for 1-2 hours. Then, most of the liquid in the sample is removed by centrifugation or filtration, and the pH of the removed washing solution is measured. This constitutes one complete water washing dealkali removal process. The sample after removing the washing solution is subjected to the water washing dealkali removal operation repeatedly until the pH of a certain washing solution differs from the previous washing solution by no more than 0.1, and the pH value is within the range of 9-10. The dealkali-removed red mud is then obtained after dehydration and drying.
[0044] Third, wet mixing of materials: Weigh out dealkalized red mud and pyrite powder in a mass ratio of 2:3, add an equal mass of pure water, and heat to 50 degrees Celsius in a stirrer for 6 hours. After stirring, dehydrate and dry the mixture according to the steps in the dealkalization treatment to obtain a mixed sample of red mud and pyrite.
[0045] Fourth, flash Joule heating: Mix the red mud-pyrite mixture sample with carbon black in a 9:1 ratio (total 0.3g, carbon black 0.03g, remainder red mud-pyrite mixture sample) to obtain a mixture, such as... Figure 2 As shown, the mixture was loaded into a rolled-up cylindrical carbon cloth, which was then clamped onto the sintering stage. The instrument was adjusted to an argon atmosphere, a voltage of 60V, and the material temperature was set to 1300℃. Heating was stopped, and the mixture was held at this temperature for 5 minutes. The material was then allowed to cool naturally to room temperature to obtain the adsorbent material. Figure 1 As shown.
[0046] Example 2
[0047] First, crushing and grinding: crush and grind the red mud into powder with a particle size of 80-100 micrometers, and then put it into a drying oven and dry it at 80 degrees Celsius for 12 hours.
[0048] Second, dealkali removal treatment: The ground red mud sample is mixed with pure water at a ratio of 1:10 and placed in a stirrer, heated to 50 degrees Celsius, and stirred continuously for 1-2 hours. Then, most of the liquid in the sample is removed by centrifugation or filtration, and the pH of the removed washing solution is measured. This constitutes one complete water washing dealkali removal process. The sample after removing the washing solution is subjected to the water washing dealkali removal operation repeatedly until the pH of a certain washing solution differs from the previous washing solution by no more than 0.1, and the pH value is within the range of 9-10. The dealkali-removed red mud is then obtained after dehydration and drying.
[0049] Third, wet mixing of materials: Weigh out dealkalized red mud and pyrite powder in a mass ratio of 2:3, add an equal mass of pure water, and heat to 50 degrees Celsius in a stirrer for 6 hours. After stirring, dehydrate and dry the mixture according to the steps in the dealkalization treatment to obtain a mixed sample of red mud and pyrite.
[0050] Fourth, flash Joule heating: Mix the mixed sample with carbon black in a 4:1 ratio (total 0.3g, carbon black 0.06g, the remainder is a mixture of red mud and pyrite) to obtain a mixture. Load the mixture into a rolled-up cylindrical carbon cloth, clamp the carbon cloth on the sintering table, adjust the instrument to argon atmosphere, voltage 60V, and material temperature to 1400℃, then stop heating, hold for 5 minutes, and allow to cool naturally to room temperature.
[0051] Example 3
[0052] First, crushing and grinding: crush and grind the red mud into powder with a particle size of 80-100 micrometers, and then put it into a drying oven and dry it at 80 degrees Celsius for 12 hours.
[0053] Second, dealkali removal treatment: The ground red mud sample is mixed with pure water at a ratio of 1:10 and placed in a stirrer, heated to 50 degrees Celsius, and stirred continuously for 1-2 hours. Then, most of the liquid in the sample is removed by centrifugation or filtration, and the pH of the removed washing solution is measured. This constitutes one complete water washing dealkali removal process. The sample after removing the washing solution is subjected to the water washing dealkali removal operation repeatedly until the pH of a certain washing solution differs from the previous washing solution by no more than 0.1, and the pH value is within the range of 9-10. The dealkali-removed red mud is then obtained after dehydration and drying.
[0054] Third, wet mixing of materials: Weigh out dealkalized red mud and pyrite powder in a mass ratio of 2:3, add an equal mass of pure water, and heat to 50 degrees Celsius in a stirrer for 6 hours. After stirring, dehydrate and dry the mixture according to the steps in the dealkalization treatment to obtain a mixed sample of red mud and pyrite.
[0055] Fourth, flash Joule heating: Mix the mixed sample with carbon black in a 4:1 ratio (total 0.3g, carbon black 0.06g, the remainder is a mixture of red mud and pyrite) to obtain a mixture. Load the mixture into a rolled-up cylindrical carbon cloth, clamp the carbon cloth on the sintering table, adjust the instrument to argon atmosphere, voltage 60V, and material temperature to 1300℃, then stop heating, hold for 10 minutes, and allow to cool naturally to room temperature.
[0056] Comparative Example 1
[0057] The difference from Example 2 is that a high-temperature calcination method is used instead of flash Joule heating; heating is stopped when the temperature reaches 1350°C, the temperature is held for 30 minutes, and then the temperature is allowed to cool naturally to room temperature.
[0058] Comparative Example 2
[0059] The difference from Example 2 is that iron tailings are used instead of red mud.
[0060] Comparative Example 3
[0061] The difference from Example 2 is that blast furnace slag is used instead of red mud.
[0062] Experimental Example
[0063] The adsorbent materials prepared in Examples 1-3 and Comparative Examples 1-3 were used to adsorb vanadium heavy metal in water. 50 mg of the adsorbent material was added to 25 mL of vanadium-containing water (vanadium concentration of 10 mg / L), and stirred for 12 h. The vanadium content in the treated water was detected by ICP determination, and the vanadium removal rate was calculated.
[0064] The test results are as follows:
[0065] Table 1. Vanadium removal rate of adsorbent materials prepared in different embodiments
[0066]
[0067] As can be seen from the comparison of Examples 1-3, the adsorbent material prepared by flash evaporation and Joule heating using red mud and pyrite as raw materials has a high removal efficiency for vanadium.
[0068] As can be seen from the comparison between Example 2 and Comparative Example 1, compared with the high-temperature roasting method, the use of steam joule heating significantly improves the adsorption activity of the adsorbent material and significantly improves the vanadium removal efficiency.
[0069] As can be seen from the comparison of Example 2 and Comparative Examples 2 and 3, compared with iron tailings and blast furnace slag, the adsorbent material prepared by using red mud as the iron source has better adsorption activity and significantly improves the vanadium removal efficiency.
[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for preparing a high-efficiency adsorption-reduction material of metal vanadium using flash Joule heating with red mud and pyrite as raw materials, characterized in that, include: The red mud was washed with water until the pH value of the washing solution stabilized at a slightly alkaline level. The mixture was then dehydrated and dried to obtain dealkalized red mud. The dealkali-treated red mud and pyrite powder were mixed evenly in water at a preset temperature. The mixture was then dehydrated and dried to obtain a red mud-pyrite mixed sample. The red mud and pyrite mixture sample was mixed evenly with carbon black to obtain a mixture; The mixture was subjected to flash Joule heating to obtain a highly efficient adsorption-reduction raw material for metallic vanadium. The mass ratio of the dealkalized red mud to pyrite is 2:(3-4). The preset temperature is 50℃-60℃; the weakly alkaline pH value range is 9-10; The mass ratio of the red mud-pyrite mixture sample to carbon black was 9:1-1.5; The voltage for flash Joule heating is 60V-80V. When the material temperature reaches 1300℃-1400℃, heating is stopped, the temperature is maintained for 5-10 minutes, and then cooled to room temperature.
2. The preparation method of the highly efficient adsorption-reduction material of metallic vanadium prepared by flash evaporation and Joule heating using red mud and pyrite as raw materials as described in claim 1, characterized in that, The preparation method of dealkalized red mud includes: mixing red mud with water and stirring at 50℃-60℃ for 1-2 hours for washing and dehydration, collecting the solid product and the washing liquid separately, and repeating the above washing and dehydration operation on the solid product until the pH value of the washing liquid is stable in the range of 9-10.
3. The preparation method of the highly efficient adsorption-reduction material of metallic vanadium prepared by flash evaporation and Joule heating using red mud and pyrite as raw materials as described in claim 1, characterized in that, The flash Joule heating is carried out under an inert atmosphere, which is argon.
4. The preparation method of the highly efficient adsorption-reduction material of metallic vanadium prepared by flash evaporation and Joule heating using red mud and pyrite as raw materials as described in claim 1, characterized in that, The particle size of the dealkalized red mud is 80-100 micrometers.
5. The method according to any one of claims 1-4 for preparing highly efficient adsorption-reduction raw materials for metallic vanadium.
6. The application of the high-efficiency vanadium adsorption-reduction material according to claim 5 in heavy metal adsorption, characterized in that, The heavy metals include vanadium.