Analcime based on alkali grinding activation and its preparation method and application

Abstract

The present invention provides analcime activated by alkali milling, and its preparation method and application. The analcime preparation method comprises the following steps: S1, providing lithium slag; S2, ball-milling a solid material and water to obtain a ball-milled product; the solid material comprises the lithium slag and an alkaline auxiliary material, wherein the alkaline auxiliary material comprises one or more of sodium hydroxide and potassium hydroxide; S3, mixing the ball-milled product with an alkaline solution to obtain a liquid to be treated; hydrothermally treating the liquid to obtain a reaction liquid; and S4, performing solid-liquid separation on the reaction liquid to obtain a solid separated material containing analcime. The present invention can produce analcime with high crystallinity and high yield, providing a new method for the preparation of analcime and a new approach for the resource recovery of lithium slag.

Description

Technical Field

[0001] The present invention relates to the field of preparation of treated analcime, in particular to analcime activated based on alkali grinding, and a preparation method and application thereof. Background Art

[0002] Lithium carbonate production processes include the traditional limestone roasting method and the widely used sulfuric acid, sulfate, and chloride roasting methods. In addition, new technologies such as alkaline dissolution, pressure cooking, and composite salt roasting have been developed. After lithium ore is batched, roasted at high temperature, and leached, lithium is extracted into a solution. However, the lithium leaching residue (hereinafter referred to as lithium slag) is stored in the factory. Lithium slag is an industrial silico-alumina waste residue, and the production of 1 ton of Li2CO3 produces approximately 20-30 tons of lithium slag. Therefore, lithium slag is an inevitable bulk solid waste generated in the lithium extraction process, facing problems such as large stockpiles and difficult resource utilization.

[0003] Analcime, a common feldspar-like mineral belonging to the zeolite family, possesses unique structure and properties. Its ion exchange, catalytic properties, thermal stability, and acid resistance make it widely used in building materials, environmental protection, daily necessities, light industry, and petrochemical industries. However, despite existing research on lithium slag treatment, analcime production has not been obtained.

[0004] Chinese invention patent application CN117643861A (the applicant's prior application) discloses a sulfur-resistant and high-temperature resistant gaseous arsenic adsorbent material, its preparation method, and its application. While the gaseous arsenic adsorbent material is produced by mechanically ball-milling and activating lithium slag, which has application value, it does not produce the more stable analcime material from the lithium slag, nor does it investigate the crystallinity and yield of the analcime.

[0005] In view of this, it is necessary to provide analcime activated by alkali grinding and a preparation method and application thereof, so as to solve or at least alleviate the technical problem of how to prepare analcime from lithium slag. Summary of the Invention

[0006] The main purpose of the present invention is to provide analcime activated by alkali grinding and its preparation method and application, aiming to solve the above-mentioned technical problem of how to prepare analcime from lithium slag.

[0007] To achieve the above object, the present invention provides a method for preparing analcime based on alkali grinding activation, comprising the steps of:

[0008] S1, providing lithium slag; the lithium slag contains Li, Si, Al, Na, K, F, and Ca;

[0009] S2, ball-milling the solid material and water to obtain a ball-milled product;

[0010] The solid material comprises the lithium slag and an alkaline auxiliary material, the mass percentage of the water to the solid material is 10-50%, the mass ratio of the alkaline auxiliary material to the lithium slag is 1:2-10, the alkaline auxiliary material comprises one or more of sodium hydroxide and potassium hydroxide, and the ball milling time is not less than 100 minutes;

[0011] S3, mixing the ball-milled product and an alkaline solution to obtain a liquid to be treated; and subjecting the liquid to be treated to a hydrothermal treatment to obtain a reaction liquid;

[0012] The alkaline solution contains an alkaline substance, and the alkaline substance includes one or more of sodium hydroxide and potassium hydroxide; the temperature of the hydrothermal treatment is 130-210° C., and the duration of the hydrothermal treatment is 40-180 minutes;

[0013] S4, performing solid-liquid separation on the reaction liquid to obtain a solid separation; the solid separation contains analcime.

[0014] Furthermore, the mass proportion of the Li element in the lithium slag is 0.1-2%, the mass proportion of the Si element in the lithium slag is 10-15%, the mass proportion of the Al element in the lithium slag is 5-12%, the mass proportion of the Na element in the lithium slag is 5-10%, the mass proportion of the K element in the lithium slag is 5-10%, the mass proportion of the F element in the lithium slag is 2-8%, and the mass proportion of the Ca element in the lithium slag is 5-10%.

[0015] Furthermore, the lithium slag contains nepheline, muscovite, and orthoclase; and the lithium slag has a framework aluminosilicate structure.

[0016] Furthermore, the alkaline auxiliary material is sodium hydroxide.

[0017] Furthermore, the rotation speed of the ball mill is 300-800 r / min, the duration of the ball milling is 120-175 min, and the ball-to-material mass ratio used in the ball milling is 4-12:1.

[0018] Furthermore, the concentration of the alkaline substance in the alkaline solution is 0.5-4 mol / L; and the mass volume ratio of the ball-milled product to the alkaline solution is 1-10 g:40-50 mL.

[0019] Furthermore, the hydrothermal treatment is carried out by microwave hydrothermal treatment, and the microwave hydrothermal treatment is carried out in a microwave hydrothermal reactor.

[0020] The present invention also provides analcime, comprising: preparing the analcime by any of the above-mentioned analcime preparation methods.

[0021] The present invention also provides a use of any of the above-mentioned analcime in arsenic removal or sulfur-resistant arsenic removal.

[0022] Furthermore, the application includes: using the analcime to adsorb arsenic in arsenic-containing flue gas; the arsenic-containing flue gas contains As2O3, or the arsenic-containing flue gas contains As2O3 and SO2;

[0023] The adsorption is carried out at a temperature of 400-900° C. and the adsorption time is 20-90 min;

[0024] When the arsenic-containing flue gas contains As2O3, the concentration of As2O3 in the arsenic-containing flue gas is not higher than 1 mg / L;

[0025] When the arsenic-containing flue gas contains As2O3 and SO2, the concentration of As2O3 in the arsenic-containing flue gas is not higher than 1 mg / L, and the volume proportion of SO2 in the arsenic-containing flue gas is not higher than 15%.

[0026] Compared with the prior art, the present invention has at least the following advantages:

[0027] The present invention can prepare analcime from lithium slag. By ball-milling lithium slag, an alkaline auxiliary material, and water, the present invention utilizes OH- in the alkaline auxiliary material to attack the aluminosilicate framework during ball milling, thereby promoting the release of silicon and aluminum elements and increasing the reactivity of the lithium slag. After ball-milling the lithium slag with a specific alkaline auxiliary material in a humid environment, the milled product is hydrothermally synthesized in a specific alkaline solution to obtain analcime with higher crystallinity and yield. Therefore, the present invention provides a new method for preparing analcime and a new approach for the resource recovery of lithium slag. The analcime in the present invention not only has high sulfur resistance and arsenic removal performance, but more importantly, it also has a higher temperature tolerance and exhibits a higher arsenic adsorption capacity at around 800°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0029] Figure 1 The XRD pattern of the lithium slag in Analysis Example 1 of the present invention is shown below:

[0030] Figure 2 Graph showing the activity index of lithium slag after ball milling at different ball milling speeds in Example 1 of the present invention;

[0031] Figure 3 Graph showing the activity index of lithium slag after ball milling at different ball milling times in Example 2 of the present invention;

[0032] Figure 4 Graph showing the activity index of lithium slag after ball milling at different ball-to-material ratios in Example 3 of the present invention;

[0033] Figure 5 Graph showing the activity index of lithium slag after ball milling at different auxiliary material ratios (different proportions) in Example 4 of the present invention;

[0034] Figure 6 Graph showing the activity index of lithium slag after ball milling at different moisture contents (different mass fractions) in Example 5 of the present invention;

[0035] Figure 7 1 is an XRD pattern of the lithium slag and the prepared product in Example 6 of the present invention; in the figure, the original slag is lithium slag, and the product is the prepared product in Example 6;

[0036] Figure 8 This is a SEM image of the product (analcime) prepared in Example 6 of the present invention;

[0037] Figure 9 This is a diagram showing the effect of the adsorbent adsorbing gaseous arsenic at different adsorption temperatures in Example 7 of the present invention;

[0038] Figure 10 This is a diagram showing the effect of the adsorbent on adsorbing gaseous arsenic at different sulfur dioxide concentrations in Example 8 of the present invention;

[0039] Figure 11 is the XRD pattern of the product prepared in Example 9 of the present invention;

[0040] Figure 12 This is the XRD pattern of the product prepared in Comparative Example 1 of the present invention;

[0041] Figure 13 This is the XRD pattern of the product prepared in Comparative Example 2 of the present invention;

[0042] Figure 14 This is the XRD pattern of the product prepared in Comparative Example 3 of the present invention;

[0043] Figure 15 This is the XRD pattern of the product prepared in Comparative Example 4 of the present invention.

[0044] The realization of the objectives, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0045] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. The embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0046] Moreover, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0047] When numerical ranges are given in the examples, it should be understood that unless otherwise specified herein, both endpoints of each numerical range and any value between the two endpoints may be used. Unless otherwise defined, all technical and scientific terms used herein are consistent with the prior art as understood by those skilled in the art and the description of the present invention. Any prior art methods, devices, and materials similar or equivalent to those described in the examples of the present invention may also be used to implement the present invention.

[0048] In the present invention, when calculating the ball-to-material ratio, lithium slag, alkaline auxiliary material, and water are all counted as materials for ball milling. In the examples and comparative examples of the present invention, alumina grinding balls are used for ball milling, and the ratio of the alumina grinding balls is large balls (15 mm diameter): medium balls (10 mm diameter): small balls (5 mm diameter) = 15:9:6. Furthermore, in the present invention, the ratio of the grinding balls can be large balls (14-16 mm diameter): medium balls (9-11 mm diameter): small balls (4-6 mm diameter) = 14-16:8-10:5-7. The microwave hydrothermal reactor used in the examples and comparative examples of the present invention is a multifunctional microwave hydrothermal parallel synthesizer, model XH-800SP, from Beijing Xianghu Technology Development Co., Ltd., with a microwave frequency of 2450 MHz.

[0049] In the present invention, the calculation formula of the activity index of lithium slag after ball milling is: Among them, α represents the activity index of lithium slag after ball milling, m1 represents the active aluminum content in lithium slag after ball milling, and m0 represents the active aluminum content in lithium slag before ball milling.

[0050] In the present invention, the aluminum that can be dissolved after alkali leaching is defined as active aluminum; wherein, the alkali leaching steps are as follows:

[0051] Prepare 100mL of 1mol / L sodium hydroxide solution and pour the solution into a 250mL beaker; place the beaker on a digital constant temperature magnetic stirrer and heat it to 60°C; add 3g of the test object (lithium slag after ball milling or lithium slag before ball milling) into the beaker and conduct an alkaline leaching experiment with a leaching time of 30min and a stirring speed of 300r / min; after the leaching is completed, filter while hot, acidify the filtrate with concentrated HNO3 to pH <2, and refrigerate for testing, and then analyze the aluminum concentration using ICP-OES; the higher the active aluminum content, the greater the activity of the lithium slag.

[0052] The present invention provides a method for preparing analcime based on alkali grinding activation, comprising the steps of:

[0053] S1, provides lithium slag.

[0054] In the present invention, the lithium slag contains Li, Si, Al, Na, K, F and Ca elements; the mass proportion of the Li element in the lithium slag is 0.1-2%, the mass proportion of the Si element in the lithium slag is 10-15%, the mass proportion of the Al element in the lithium slag is 5-12%, the mass proportion of the Na element in the lithium slag is 5-10%, the mass proportion of the K element in the lithium slag is 5-10%, the mass proportion of the F element in the lithium slag is 2-8%, and the mass proportion of the Ca element in the lithium slag is 5-10%.

[0055] In the present invention, the lithium slag contains nepheline, muscovite and orthoclase; the lithium slag has aluminosilicate, especially a framework aluminosilicate structure.

[0056] S2, ball-milling the solid material and water to obtain a ball-milled product.

[0057] In the present invention, the solid material includes the lithium slag and an alkaline auxiliary material, and the alkaline auxiliary material includes one or more of sodium hydroxide and potassium hydroxide. In order to further improve the crystallinity and yield of analcime, the alkaline auxiliary material is preferably sodium hydroxide.

[0058] In the present invention, the mass percentage of the water and the solid material is 10-50%, preferably 25-35%; the mass ratio of the alkaline auxiliary material to the lithium slag is 1:2-10, preferably 1:4-6 or 1:5; the ball milling time is not less than 100 min, preferably not less than 120 min or 120-175 min, and further can be 120-130 min; the ball milling speed is 300-800 r / min, preferably 500-580 r / min or 500-560 r / min; the ball-to-material mass ratio used in the ball milling is 4-12:1, preferably 7-8:1 or 8:1.

[0059] When the ball milling is carried out, the present invention performs forward rotation and reverse rotation in sequence, and there is an interval between forward rotation and reverse rotation, and between reverse rotation and forward rotation; wherein, the set time of each forward rotation is 5-15 minutes (specifically 10 minutes), the set time of each reverse rotation is 5-15 minutes (specifically 10 minutes), and the interval time is set to 3-7 minutes (specifically 5 minutes); when the ball milling time reaches the set time, the ball milling is stopped, and the interval time is counted into the ball milling time.

[0060] S3, mixing the ball-milled product and an alkaline solution to obtain a liquid to be treated; and subjecting the liquid to be treated to a hydrothermal treatment (hydrothermal reaction) to obtain a reaction liquid.

[0061] In the present invention, the alkaline solution contains an alkaline substance, and the concentration of the alkaline substance in the alkaline solution is 0.5-4 mol / L, preferably 0.8-1.2 mol / L; the alkaline substance includes one or more of sodium hydroxide and potassium hydroxide.

[0062] In the present invention, the temperature of the hydrothermal treatment is 130-210°C, preferably 140-160°C; the duration of the hydrothermal treatment is 40-180 min, preferably 110-130 min; the mass volume ratio of the ball-milled product to the alkaline solution is 1-10 g:40-50 mL, preferably 3 g:40-50 mL.

[0063] The hydrothermal treatment may be microwave hydrothermal treatment, which is performed in a microwave hydrothermal reactor. By employing this microwave hydrothermal treatment, the materials in the reactor can be treated with microwaves during the synthesis phase, accelerating the formation of crystal nuclei during the reaction process, resulting in a smaller analcime particle size and a more uniform particle size distribution.

[0064] S4, performing solid-liquid separation on the reaction liquid to obtain a solid separation (separation residue), wherein the solid separation contains analcime.

[0065] The technical principles of the present invention mainly include:

[0066] First, mechanical ball milling activates and enhances the activity of lithium slag. Mechanical ball milling utilizes rotating drums to cause continuous collision, shearing, and friction between the grinding balls and the material within the mill, crushing and mixing the material and enhancing its surface activity. This results in micronization and redispersion of the material surface, accelerating chemical reactions.

[0067] Secondly, during the ball milling process, the OH in the alkaline auxiliary material is used to -During ball milling, the alkaline auxiliary material attacks the aluminosilicate skeleton, promotes the release of silicon and aluminum elements, and enhances the reaction activity of lithium slag for subsequent microwave hydrothermal synthesis; at the same time, during the ball milling process, the alkaline auxiliary material can also serve as a grinding aid.

[0068] Third, the present invention has specific requirements for the type of alkaline auxiliary materials, mainly because Na + , K + It can be used as an inorganic template during hydrothermal treatment; however, the introduction of Ca 2+ Mg 2+ It will promote volcanic ash reaction and thus inhibit the formation of analcime.

[0069] Fourthly, the present invention has specific requirements for the humidity during the ball milling process, mainly because appropriate moisture can better react with OH - Synergistically destroy the lithium slag structure, thereby promoting the release of Si and Al elements.

[0070] Fifth, the lithium slag activated by ball milling with alkali is subjected to hydrothermal synthesis. The lithium slag activated by ball milling is dissolved, diffused, monomer reconstructed, and condensed in a hydrothermal environment, so that the lithium slag hydrothermal crystallizes to form analcime.

[0071] Sixth, the present invention has specific requirements for the alkaline solution used in hydrothermal treatment, mainly due to the fact that OH - The concentration will affect the crystallization rate of zeolite, so it is necessary to use an appropriate concentration; and if other alkaline solutions are introduced into the Ca 2+ Mg 2+ , which will promote volcanic ash reaction and thus inhibit the formation of analcime.

[0072] Seventh, the present invention can utilize the F element in lithium slag in situ to play the role of inorganic template during hydrothermal treatment and simultaneously react with Ca 2+ Combined with the formation of CaF2 precipitation, it inhibits the volcanic ash reaction and promotes the formation of analcime.

[0073] The present invention subjects lithium slag to mechanical ball milling activation and hydrothermal synthesis in a specific manner to obtain analcime; analcime is used as an adsorbent to adsorb gaseous arsenic, which can effectively control the emission of gaseous arsenic in non-ferrous smelting enterprises and provide a new resource utilization approach for the disposal of lithium slag in the lithium carbonate industry.

[0074] To this end, the present invention further provides analcime, comprising: preparing the analcime using any of the above-mentioned analcime preparation methods.

[0075] The present invention also provides the use of any of the aforementioned analcime for arsenic removal or sulfur-resistant arsenic removal. Specifically, the analcime, obtained by mechanically ball-milling and hydrothermally synthesizing lithium slag, can be used to adsorb gaseous arsenic. Its structure is more stable and its adsorption capacity is large, thus reducing gaseous arsenic emissions from nonferrous metallurgical enterprises.

[0076] As an illustration of the use of analcime in arsenic removal, the application includes: using the analcime to adsorb arsenic in arsenic-containing flue gas; the arsenic-containing flue gas contains As2O3, and other components in the arsenic-containing flue gas may include or be oxygen, argon, and carbon dioxide; the adsorption is carried out at a temperature of 400-900°C (preferably 750-850°C or 750-800°C), and the adsorption time is 20-90min or 30-90min (preferably 25-35min); when the arsenic-containing flue gas contains As2O3, the concentration of As2O3 in the arsenic-containing flue gas is not higher than 1mg / L (preferably 0.5-0.8mg / L).

[0077] As an illustration of the use of analcime in sulfur resistance and arsenic removal, the application includes: using the analcime to adsorb arsenic in arsenic-containing flue gas; the arsenic-containing flue gas contains As2O3 and SO2, and other components in the arsenic-containing flue gas may include or be oxygen, argon, and carbon dioxide; the adsorption is carried out at a temperature of 400-900°C (preferably 750-850°C or 750-800°C), and the adsorption time is 20-90min or 30-90min (preferably 25-35min); when the arsenic-containing flue gas contains As2O3 and SO2, the concentration of As2O3 in the arsenic-containing flue gas is not higher than 1 mg / L (preferably 0.5-0.8 mg / L), and the volume proportion of SO2 in the arsenic-containing flue gas is not higher than 15% (preferably 4-6% or 5-10%).

[0078] The following are specific examples of the present invention:

[0079] Analysis example 1

[0080] Take the lithium slag stored in a lithium carbonate production company in Jiangxi.

[0081] 1. In this analysis example, the elemental composition of lithium slag is shown in Table 1. In Table 1, Rb* and Cs* are tested by digestion-ICP, and the remaining elements are tested by XRF.

[0082] Table 1 Elemental composition of lithium slag (mass %)

[0083]

[0084] 2. In this analysis, lithium slag contains nepheline, muscovite, and orthoclase. For XRD analysis of lithium slag, see Figure 1 As shown; after analysis, the lithium slag has a framework aluminosilicate structure.

[0085] Example 1

[0086] The lithium slag in Analysis Example 1 was taken and ball milled at ball mill speeds of 300, 350, 400, 450, 500, 550, 600, 650, and 700 r / min, respectively, to obtain ball milling products at different ball milling speeds; the ball-to-material ratio used in the ball milling was 6:1, and the ball milling time was 25 min (the ball mill was set to rotate forward for 10 min, then rotate for 5 min, and then rotate backward for 10 min).

[0087] The activity index of the ball milling products (lithium slag after ball milling) at different ball milling speeds was tested; Figure 2 As shown in the figure, when the ball milling speed is 550r / min, the activity index of the lithium slag after ball milling reaches 9.1.

[0088] Example 2

[0089] The lithium slag in Analysis Example 1 was taken and ball milled under the conditions of ball milling time of 25, 50, 75, 100, 125, 150, 200, and 250 min respectively (the ball mill was set to rotate forward for 10 min, interval of 5 min, reverse for 10 min, interval of 5 min), and ball milling products under different ball milling times were obtained; the ball-to-material ratio used in the ball milling was 6:1, and the ball milling speed was 550 r / min.

[0090] The activity index of the ball milling products (lithium slag after ball milling) at different ball milling times was tested; Figure 3 As shown in the figure, when the ball milling time reaches 125 min, the activity index of lithium slag after ball milling basically no longer increases, and the activity index reaches 15.2 at this time.

[0091] Example 3

[0092] The lithium slag in Analysis Example 1 was taken and ball milled under the conditions of ball-to-material ratios of 4:1, 6:1, 8:1, and 10:1, respectively. The ball milling products under different ball milling ratios were obtained; the ball milling time used was 125 min (the ball mill was set to rotate forward for 10 min, with an interval of 5 min, and reverse for 10 min, with an interval of 5 min), and the ball milling speed was 550 r / min.

[0093] The activity index of the ball milling products (lithium slag after ball milling) under different ball-to-material ratios was tested; Figure 4 As shown in the figure, when the ball-to-material ratio is 8:1, the activity index of the lithium slag after ball milling reaches 20; when the ball-to-material ratio is 10:1, the activity index of the lithium slag after ball milling drops rapidly. It is speculated that there may be too little material, causing part of the lithium slag to adhere to the ball mill jar and grinding balls, resulting in systematic errors and making the measured value smaller.

[0094] Example 4

[0095] Take the lithium slag in Analysis Example 1, and ball-mill NaOH and lithium slag together at a mass ratio of 0, 1:5, 2:5, 3:5, 4:5, and 1:1, respectively, to obtain ball-milled products under different ratios (auxiliary material ratios); the ball-to-material ratio used in ball milling is 8:1, the ball milling time is 125 min (the ball mill is set to rotate forward for 10 min, with an interval of 5 min, and reverse for 10 min, with an interval of 5 min), and the ball milling speed is 550 r / min.

[0096] The activity index of the ball milling product (lithium slag after ball milling) under different ratios (auxiliary material ratio) was tested; Figure 5 As shown in the figure, when the mass ratio of sodium hydroxide to lithium slag is 1:5, the activity index of lithium slag after ball milling reaches 22.4. When the ratio of sodium hydroxide to lithium slag exceeds 1:5, the material becomes compacted and the activity index of lithium slag decreases rapidly.

[0097] Example 5

[0098] Take the lithium slag in Analysis Example 1, use NaOH and lithium slag as solid materials, and ball-mill water and solid material at mass fractions of 0%, 10%, 20%, 30%, 40%, and 50% (mass percentage of water and solid material) to obtain ball-milled products at different mass fractions; the ball-to-material ratio used in ball milling is 8:1, the mass ratio of NaOH and lithium slag is 1:5, the ball milling time is 125 min (the ball mill is set to rotate forward for 10 min, interval 5 min, reverse for 10 min, interval 5 min), and the ball milling speed is 550 r / min.

[0099] The activity index of the ball-milled products (lithium slag after ball-milling) at different mass fractions (different water contents) was tested; Figure 6 As shown in FIG, when the moisture content (mass percentage of water and solid material) is 30%, the lithium slag activity index reaches 27.5.

[0100] Example 6

[0101] Take the lithium slag from Analytical Example 1, use NaOH and the lithium slag as solid materials, and ball-mill the water and solid materials together to obtain a ball-milled product (lithium slag after ball milling). In this embodiment, the mass ratio of NaOH to lithium slag is 1:5, the mass percentage of water to solid materials is 30%; the ball-to-material ratio is 8:1, the ball milling time is 125 minutes (the ball mill is set to rotate forward for 10 minutes, then rest for 5 minutes, then reverse for 10 minutes, then rest for 5 minutes), and the ball milling speed is 550 rpm.

[0102] Weigh 3 g of the ball-milled product into a microwave hydrothermal reactor, add 45 mL of 1 mol / L NaOH solution (alkaline solution), and perform hydrothermal reaction (microwave hydrothermal reaction). The hydrothermal reaction temperature is 150°C, and the hydrothermal reaction time is 120 min. After the hydrothermal reaction is completed, a reaction solution is obtained.

[0103] The reaction solution was centrifuged at 8000 r / min for 10 minutes at room temperature and vacuum filtered to achieve solid-liquid separation, thereby obtaining a separated liquid and a separated residue; the separated residue was dried to obtain the prepared product.

[0104] The prepared product was subjected to XRD measurement to confirm whether it was analcime; the crystallinity of the prepared product was calculated using jade software; the aluminum content in the separation liquid was measured by ICP, and the analcime yield was calculated by the proportion of aluminum consumed in the reaction in the total aluminum (aluminum in the lithium slag), the aluminum in the separation liquid was defined as unconsumed aluminum, and the aluminum entering the separation slag was defined as aluminum consumed in the reaction; the prepared product was subjected to SEM analysis to observe its structure.

[0105] like Figure 7 As shown, the product prepared in this embodiment is analcime; the crystallinity is 49.4%; the analcime yield is 42.8%; see Figure 8 As shown, the analcime of this embodiment has a loose and porous structure.

[0106] Example 7

[0107] 0.1 g of the product prepared in Example 6 (analcime) was taken as an adsorbent, and the adsorbent was placed in a gaseous arsenic adsorption system to conduct an arsenic adsorption experiment with an adsorption time of 30 min.

[0108] In this embodiment, the gaseous arsenic adsorption system consists of an arsine generator, an adsorption reactor, and an exhaust gas treatment system. The generator produces arsine, which enters the adsorption reactor along with the simulated flue gas. The adsorption reactor consists of a two-stage reactor. Arsine enters the first stage, where it is oxidized to arsenic trioxide. The arsenic trioxide then enters the second stage for an adsorption reaction. The exhaust gas is discharged through the exhaust gas treatment system.

[0109] In this embodiment, the atmosphere of the simulated flue gas is O2 5%, Ar 87%, SO2 5%, and CO2 3% by volume, and the flue gas flow rate is 400 mL / min; the concentration of As2O3 in the simulated flue gas is 0.6 mg / L.

[0110] In this embodiment, the above arsenic adsorption experiments were carried out at adsorption temperatures of 400, 500, 600, 700, and 800°C, respectively.

[0111] See also Figure 9As shown, the prepared product (analcime) in Example 6 can adsorb gaseous arsenic (referring to As2O3) in an amount of 22.4 mg / g at an adsorption temperature of 800°C, and has excellent gaseous arsenic adsorption capacity.

[0112] Example 8

[0113] 0.1 g of the product prepared in Example 6 (analcime) was taken as an adsorbent, and the adsorbent was placed in a gaseous arsenic adsorption system to conduct an arsenic adsorption experiment. The adsorption temperature was 400° C. and the adsorption time was 30 min.

[0114] In this embodiment, the gaseous arsenic adsorption system consists of an arsine generator, an adsorption reactor, and an exhaust gas treatment system. The generator produces arsine, which enters the adsorption reactor along with the simulated flue gas. The adsorption reactor consists of a two-stage reactor. Arsine enters the first stage, where it is oxidized to arsenic trioxide. The arsenic trioxide then enters the second stage for an adsorption reaction. The exhaust gas is discharged through the exhaust gas treatment system.

[0115] In this example, the above arsenic adsorption experiment was carried out on different simulated flue gases; the compositions of the simulated flue gases were:

[0116] By volume percentage, the atmosphere used in the simulated flue gas (corresponding to 0%) is O2 5%, Ar 92%, SO20%, and CO23%, and the flue gas flow rate is 400 mL / min; the concentration of As2O3 in the simulated flue gas is 0.6 mg / L.

[0117] By volume, the atmosphere used in the simulated flue gas (corresponding to 5%) is O2 5%, Ar 87%, SO2 5%, and CO2 3%, and the flue gas flow rate is 400 mL / min; the concentration of As2O3 in the simulated flue gas is 0.6 mg / L.

[0118] By volume, the atmosphere used for the simulated flue gas (corresponding to 10%) is O2 5%, Ar 82%, SO2 10%, and CO2 3%, and the flue gas flow rate is 400 mL / min; the concentration of As2O3 in the simulated flue gas is 0.6 mg / L.

[0119] See also Figure 10 As shown, when the SO2 concentration is 5%, the gaseous arsenic (referring to As2O3) adsorption capacity of the product (analcime) prepared in Example 6 can reach 16.78 mg / g, which has excellent gaseous arsenic adsorption capacity.

[0120] Example 9

[0121] 1. Obtaining the prepared product:

[0122] When obtaining the prepared product, compared with Example 6, the NaOH in the solid material in this example was adjusted to KOH, and other conditions remained unchanged.

[0123] In this embodiment, see Figure 11 As shown, the prepared product is analcime with a crystallinity of 43.2% and analcime yield of 38.7%.

[0124] 2. Arsenic adsorption experiment:

[0125] When conducting the arsenic adsorption experiment, compared with Example 7, the adsorbent in this example was adjusted to the prepared product in this example, and the adsorption temperature was limited to 800° C., while other conditions remained unchanged.

[0126] In this embodiment, the adsorption capacity of gaseous arsenic (representing As 2 O 3 ) by the adsorbent is 21.8 mg / g.

[0127] Comparative Example 1

[0128] 1. Obtaining the prepared product:

[0129] When obtaining the prepared product, this comparative example is compared with Example 6, in which the alkaline solution used in the hydrothermal process is adjusted to a hydrochloric acid solution, and other conditions remain unchanged.

[0130] In this comparative example, see Figure 12 As shown, no analcime was generated in the product.

[0131] 2. Arsenic adsorption experiment:

[0132] When conducting the arsenic adsorption experiment, compared with Example 7, the adsorbent in this comparative example was adjusted to the prepared product in this comparative example, and the adsorption temperature was limited to 800° C., while other conditions remained unchanged.

[0133] In this comparative example, the adsorption capacity of gaseous arsenic (referred to as As2O3) by the adsorbent is 1.72 mg / g.

[0134] Comparative Example 2

[0135] 1. Obtaining the prepared product:

[0136] When obtaining the prepared product, compared with Example 6, this comparative example directly ball-milled NaOH and lithium slag as solid materials (without adding water), and other conditions remained unchanged.

[0137] In this comparative example, see Figure 13 As shown, the prepared product is analcime with a crystallinity of 35.3% and analcime yield of 32.0%.

[0138] 2. Arsenic adsorption experiment:

[0139] When conducting the arsenic adsorption experiment, compared with Example 7, the adsorbent in this comparative example was adjusted to the prepared product in this comparative example, and the adsorption temperature was limited to 800° C., while other conditions remained unchanged.

[0140] In this comparative example, the adsorption capacity of gaseous arsenic (referred to as As2O3) by the adsorbent is 20.85 mg / g.

[0141] Comparative Example 3

[0142] 1. Obtaining the prepared product:

[0143] When obtaining the prepared product, compared with Example 6, the lithium slag was directly ball-milled in this comparative example (without adding NaOH and water), and other conditions remained unchanged.

[0144] In this comparative example, see Figure 14 As shown, analcime was generated in the prepared product, but the crystallinity was only 13.1% and the yield was 8.1%.

[0145] 2. Arsenic adsorption experiment:

[0146] When conducting the arsenic adsorption experiment, compared with Example 7, the adsorbent in this comparative example was adjusted to the prepared product in this comparative example, and the adsorption temperature was limited to 800° C., while other conditions remained unchanged.

[0147] In this comparative example, the adsorption capacity of gaseous arsenic (referred to as As2O3) by the adsorbent is 13.69 mg / g.

[0148] Comparative Example 4

[0149] 1. Obtaining the prepared product:

[0150] When obtaining the prepared product, compared with Example 6, this comparative example used the ball-milled product directly as the prepared product (without performing the hydrothermal process), and other conditions remained unchanged.

[0151] In this comparative example, see Figure 15 As shown, the ball milling product is amorphous aluminosilicate.

[0152] 2. Arsenic adsorption experiment:

[0153] When conducting the arsenic adsorption experiment, compared with Example 7, the adsorbent in this comparative example was adjusted to the prepared product in this comparative example, and the adsorption temperature was limited to 800° C., while other conditions remained unchanged.

[0154] In this comparative example, the adsorption capacity of gaseous arsenic (referred to as As2O3) by the adsorbent is 10.13 mg / g.

[0155] The above technical solutions of the present invention are only preferred embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made by using the contents of the present invention's description and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for preparing analcime based on alkali grinding activation, characterized in that: Including steps: S1, providing lithium slag; the lithium slag contains Li, Si, Al, Na, K, F, and Ca; S2, ball-milling the solid material and water to obtain a ball-milled product; The solid material comprises the lithium slag and an alkaline auxiliary material, the mass percentage of the water to the solid material is 10-50%, the mass ratio of the alkaline auxiliary material to the lithium slag is 1:2-10, the alkaline auxiliary material comprises one or more of sodium hydroxide and potassium hydroxide, and the ball milling time is not less than 100 minutes; S3, mixing the ball-milled product and an alkaline solution to obtain a liquid to be treated; and subjecting the liquid to be treated to a hydrothermal treatment to obtain a reaction liquid; The alkaline solution contains an alkaline substance, and the alkaline substance includes one or more of sodium hydroxide and potassium hydroxide; the temperature of the hydrothermal treatment is 130-210° C., and the duration of the hydrothermal treatment is 40-180 minutes; S4, performing solid-liquid separation on the reaction liquid to obtain a solid separation; the solid separation contains analcime.

2. The method for preparing analcime according to claim 1, wherein The mass proportion of the Li element in the lithium slag is 0.1-2%, the mass proportion of the Si element in the lithium slag is 10-15%, the mass proportion of the Al element in the lithium slag is 5-12%, the mass proportion of the Na element in the lithium slag is 5-10%, the mass proportion of the K element in the lithium slag is 5-10%, the mass proportion of the F element in the lithium slag is 2-8%, and the mass proportion of the Ca element in the lithium slag is 5-10%.

3. The method for preparing analcime according to claim 1, wherein The lithium slag contains nepheline, muscovite and orthoclase; and the lithium slag has a framework-like aluminosilicate structure.

4. The method for preparing analcime according to claim 1, wherein The alkaline auxiliary material is sodium hydroxide.

5. The method for preparing analcime according to claim 1, wherein: The rotation speed of the ball mill is 300-800 r / min, the duration of the ball milling is 120-175 min, and the ball-to-material mass ratio used in the ball milling is 4-12:

1.

6. The method for preparing analcime according to claim 1, wherein: The concentration of the alkaline substance in the alkaline solution is 0.5-4 mol / L; the mass volume ratio of the ball-milled product to the alkaline solution is 1-10 g:40-50 mL.

7. The method for preparing analcime according to claim 1, wherein: The hydrothermal treatment is carried out in a microwave hydrothermal reactor.

8. Analcime, characterized in that: include: The analcime is prepared by the analcime preparation method according to any one of claims 1 to 7.

9. Use of the analcime according to claim 8 in arsenic removal or sulfur-resistant arsenic removal.

10. The use according to claim 9, characterized in that The application includes: using the analcime to adsorb arsenic in arsenic-containing flue gas; the arsenic-containing flue gas contains As2O3, or the arsenic-containing flue gas contains As2O3 and SO2; The adsorption is carried out at a temperature of 400-900° C. and the adsorption time is 20-90 minutes; When the arsenic-containing flue gas contains As2O3, the concentration of As2O3 in the arsenic-containing flue gas is not higher than 1 mg / L; When the arsenic-containing flue gas contains As2O3 and SO2, the concentration of As2O3 in the arsenic-containing flue gas is not higher than 1 mg / L, and the volume proportion of SO2 in the arsenic-containing flue gas is not higher than 15%.

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