CN113003579B - Green method for comprehensive utilization of coal gangue - Google Patents
Green method for comprehensive utilization of coal gangue Download PDFInfo
- Publication number
- CN113003579B CN113003579B CN202110306087.5A CN202110306087A CN113003579B CN 113003579 B CN113003579 B CN 113003579B CN 202110306087 A CN202110306087 A CN 202110306087A CN 113003579 B CN113003579 B CN 113003579B
- Authority
- CN
- China
- Prior art keywords
- coal gangue
- silicon
- waste liquid
- green method
- acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/30—Active carbon
- C01B32/312—Preparation
- C01B32/318—Preparation characterised by the starting materials
- C01B32/324—Preparation characterised by the starting materials from waste materials, e.g. tyres or spent sulfite pulp liquor
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/30—Active carbon
- C01B32/312—Preparation
- C01B32/342—Preparation characterised by non-gaseous activating agents
- C01B32/348—Metallic compounds
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/483—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides for non-aqueous cells
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/30—Particle morphology extending in three dimensions
- C01P2004/32—Spheres
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/14—Pore volume
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/16—Pore diameter
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/40—Electric properties
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/027—Negative electrodes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention discloses a green method for comprehensively utilizing coal gangue, belonging to the technical field of coal gangue development and utilization; the method of the invention comprises C/SiO x The preparation process of the composite lithium battery negative electrode material comprises a preparation process of silicon dioxide microspheres, a process of gradually adding an alkali solution into acid liquor after soaking coal gangue to separate metal hydroxide precipitate, and a preparation process of a nitrogen-phosphorus-potassium compound fertilizer; a set of complete, zero-emission and zero-pollution green method for comprehensively utilizing the coal gangue is formed by mutual coupling of various processes.
Description
Technical Field
The invention relates to a green method for comprehensively utilizing coal gangue, belonging to the technical field of coal gangue development and utilization.
Background
Coal gangue is a solid waste produced during coal mining and washing processes, and the yield of the coal gangue accounts for about 18% of the annual coal yield. China is a big coal producing country, the coal yield is increased year by year, and the annual discharge amount of coal gangue is increased continuously. In 2005, the production of domestic coal gangue was 3.47 million tons; in 2010, the production amount of domestic coal gangue is 5.94 hundred million tons; by 2015, the domestic coal gangue yield reaches 7.76 hundred million tons. In addition, in 2010, the comprehensive utilization rate of coal gangue in China is about 61.4%, and the annual utilization rate of coal gangue is nearly 3.65 hundred million tons. At present, the main utilization modes of the coal gangue are as follows: the method comprises the following steps of coal gangue power generation, building material product production, foundation building and paving, land reclamation, subsidence area treatment, underground filling and coal changing and the like. The coal gangue underground filling and coal replacement technology realizes no well lifting and no land occupation of the coal gangue. However, it is subject to transportation, market environment and hairThe limit of the installed electric capacity and other factors influence the comprehensive utilization rate of coal gangue in some areas, and a large amount of coal gangue is stacked in the open air. According to statistics of relevant departments, 45 hundred million tons of coal gangue are accumulated in China, and the occupied land is about 1.5 hectare. The coal gangue mainly comprises C (28.92%), H, O, N, S and other elements and inorganic minerals, and the inorganic component is mainly Al 2 O 3 (22.76%) and SiO 2 （34.16%）。
Disclosure of Invention
The invention aims to provide a brand-new green method for comprehensively utilizing coal gangue, and solve the problem of recycling the coal gangue.
The technical scheme adopted by the invention is as follows: a green method for comprehensive utilization of coal gangue includes C/SiO x The preparation process of the negative electrode material of the composite lithium battery comprises the following operation steps:
step 2, soaking the coal gangue prepared in the step 1 in hot alkali solution to remove part of silicon dioxide in the coal gangue, and then filtering to obtain silicon-removed coal gangue;
step 3, drying the silicon-removed coal gangue prepared in the step 2, activating the dried silicon-removed coal gangue under the condition of taking nitrogen as protective gas, washing the dried silicon-removed coal gangue with distilled water and phosphoric acid, and removing the activating agent to obtain C/SiO x Disclosed is a composite lithium battery negative electrode material.
The more specific operation method of the steps is as follows:
in the step 1, coal gangue is crushed and sieved by a 60-100 mesh sieve; the acid solution is 2-5mol/L nitric acid solution, and the dosage is 1-4 (g: mL) of solid-liquid; the soaking time is 12-24 h, and then the coal gangue and the acid liquor are filtered and separated; washing the acid-leached coal gangue to neutrality by using distilled water to obtain pure coal gangue with metal impurities removed and acid-containing washing waste liquid;
in the step 2, the adopted hot alkali solution is 3-5mol/L KOH solution, the using amount is 1 to 10 (g: mL) of the solid-to-liquid ratio, the solution is soaked for 2 to 10 hours at the temperature of 20 to 60 ℃, and then the solution is filtered and separated to obtain silicon-containing extracting solution and silicon-removed coal gangue;
in step 3, the temperature is 600-1000 DEG CActivating for 2-6h under the condition; then washing with distilled water and 2-5mol/L phosphoric acid to remove the activator to obtain C/SiO x The composite lithium battery cathode material and the washing waste liquid.
One preferred scheme is as follows:
in the step 1, 3mol/L nitric acid solution is adopted as the acid solution, and the dosage is 1;
in the step 2, a hot alkali solution is 3mol/L KOH solution, the using amount is 1 (g: mL) of the solid-to-liquid ratio, the mixture is soaked for 4 to 8 hours at the temperature of 40 ℃, and then is filtered and separated to obtain a silicon-containing extracting solution and silicon-removed coal gangue;
in step 3, activation is carried out for 3 hours at a temperature of 700 ℃.
Further, the method also comprises a preparation process of the silicon dioxide microspheres, and the following step 4:
mixing the silicon-containing extracting solution prepared in the step 2 with distilled water and ethanol to prepare a silicon-containing diluent, wherein the volume ratio of the silicon-containing diluent to the distilled water to the ethanol is 1:0.1-2:0.1 to 2; dropwise adding 2-5mol/L nitric acid solution into the silicon-containing diluent at a dropwise adding rate of 1-5mL/min, enabling the pH value of the silicon-containing diluent to reach 2-9 under the condition that the magnetic stirring speed is 100-500rpm, and continuously stirring and precipitating for 3-6h; then, centrifugally separating to obtain a silicon dioxide precursor and alcohol-containing waste liquid; drying the silicon dioxide precursor in vacuum at the temperature of 50-100 ℃; then, calcining for 3-6h at the temperature of 500-700 ℃ to obtain the low-surface-area silicon dioxide microspheres.
One preferred scheme is as follows: in the step 4, the volume ratio of the silicon-containing extracting solution to the distilled water to the ethanol is 1:1.5:0.5; then, dropwise adding 3mol/L nitric acid solution into the silicon-containing diluent at the dropwise adding rate of 3mL/min, enabling the pH value of the silicon-containing diluent to reach 8 under the condition that the magnetic stirring speed is 100rpm, and continuously stirring and precipitating for 4 hours; then, centrifugally separating to obtain a silicon dioxide precursor and alcohol-containing waste liquid; drying the silicon dioxide precursor in vacuum at the temperature of 90 ℃; and then, calcining for 4 hours at the temperature of 550 ℃ to obtain the low-surface-area silica microspheres.
Furthermore, the method also comprises a process step 5 of adding an alkali solution to the acid liquor obtained after soaking the coal gangue step by step to separate the metal hydroxide precipitate in the step 1.
One preferred scheme is as follows: the operation method of the step 5 comprises the following steps: adjusting the pH value of the acid liquor obtained by filtering and separating the coal gangue soaked in the step 1 to 3.7 by using 3-5mol/L KOH solution to obtain ferric hydroxide precipitate, and filtering and separating; then continuously adjusting to 4.7 to obtain aluminum hydroxide precipitate, and filtering and separating; and continuously adjusting the pH value to 12 until no precipitate is generated, and separating the metal hydroxide precipitate and the alkaline waste liquid.
Further, the method also comprises a process for recycling the ethanol, and comprises the following step 6: and (4) distilling the alcohol-containing waste liquid obtained in the step (4) to obtain alcohol-free waste liquid and ethanol, and recovering the ethanol obtained by distillation for use in the step (4).
Further, the method also comprises a preparation process of the nitrogen-phosphorus-potassium compound fertilizer, and the following step 7 is to uniformly mix the alcohol-free waste liquid obtained in the step 6, the acid-containing washing waste liquid obtained in the step 1, the alkaline waste liquid obtained in the step 5 and the washing waste liquid obtained in the step 3 to be neutral to obtain the liquid compound fertilizer; and distilling to obtain the nitrogen-phosphorus-potassium compound fertilizer.
The invention has the beneficial effects that: the process features of the invention are summarized as follows:
firstly, in the invention, the coal gangue is treated by acid soaking to remove metal oxides, and the obtained solid residue mainly contains amorphous carbon and silicon dioxide. Wherein, the three elements of C, si and O are uniformly distributed without a complex carbon coating process. The invention utilizes the inherent characteristics of acid treatment coal gangue to prepare porous C/SiO in situ x Composite material, porous C/SiO obtained x The composite material is used as a negative electrode of a lithium ion battery.
In addition, each component in the coal gangue and each chemical reagent added are fully utilized in the process, zero emission and zero pollution are achieved, and contribution is made to high-valued comprehensive utilization of the coal gangue; the method comprises the following specific steps:
firstly, the acid soaking solution contains metal ions such as Al, fe and the like, the acid soaking solution is neutralized and precipitated by alkaline solution and is adjusted to be alkaline to obtain Al (OH) 3 、Fe(OH) 3 And waiting for the metal hydroxide to recycle the metal elements in the coal gangue.And secondly, soaking the acid-treated coal gangue with alkali, removing part of silicon dioxide in the acid-soaked coal gangue, and controlling the content of the silicon dioxide to obtain the silicon-removed coal gangue with controllable silicon dioxide content. The silicon-removed coal gangue is carbonized, activated and remolded in the pore canal of the silicon-removed coal gangue by taking residual alkali liquor as an activating agent to prepare the graded porous C/SiO x A negative electrode material for lithium batteries. The C/SiO can be effectively controlled by alkali heat soaking x Silicon content, siO, in lithium battery negative electrode materials x The content is a determining factor of the electrochemical performance of the electrode material, so that the alkaline hot soaking is one of the key technologies of the patent.
Secondly, the pore canals of the silicon-removed coal gangue are carbonized, activated and remolded by using residual alkali to obtain graded porous C/SiO x The difficulty of the method is that the activation time, the activation temperature and the residual alkali content determine C/SiO x Pore structure, each component content and Si/O of the lithium battery cathode material. Wherein, the pore channel structure, the content of each component and Si/O to C/SiO of the material x The specific capacity, the cycling stability, the rate capability, the conductivity and the first coulombic efficiency of the lithium battery cathode material are decisive, so that the unique carbonization and activation process condition is one of the key technologies of the patent.
Thirdly, if the waste liquid after the alkali-heat soaking treatment contains soluble silicate, if the soluble silicate is discharged to the nature, redundant residual alkali pollutes the environment and wastes resources, but in the invention, the low-specific-surface-area silicon dioxide is prepared by a chemical titration method, wherein the low-specific-surface-area silicon dioxide can be used as hydrophobic materials such as tooth materials, ceramic materials and the like and has high utilization value; when the low-specific-surface-area silicon dioxide is prepared, the volume ratio of distilled water, ethanol and alkali hot soaking waste liquid, the acid liquid concentration, the titration rate, the magnetic stirring rate and the pH value of a titration end point are very important to the shape, the particle size distribution and the particle size of the low-specific-surface-area silicon dioxide, and particularly, the magnetic stirring rate has a decisive effect on the particle size distribution and the particle size of the silicon dioxide and needs to be strictly controlled.
Fourthly, ethanol, nitric acid, phosphoric acid and potassium hydroxide are used in the whole production process, the substances are finally remained in washing wastewater and titration wastewater in various forms, if the substances are not recycled, the substances are directly discharged, the environment is polluted, resources are wasted, in the invention, waste liquid is collected to prepare the nitrogen-phosphorus-potassium compound fertilizer, and ethanol and distilled water are recycled, so that zero emission and zero pollution are finally realized. The prepared nitrogen-phosphorus-potassium compound fertilizer contains partial trace metal or non-metal elements in the coal gangue, is favorable for supplementing the requirement of plant growth on the trace elements, and partial acid-soluble organic components in the coal gangue can be dissolved out during acid soaking treatment and finally enter the nitrogen-phosphorus-potassium compound fertilizer, so that the nitrogen-phosphorus-potassium compound fertilizer prepared by the method is more favorable for the growth and development of plants than the commercial compound fertilizer.
Drawings
FIG. 1 is a block diagram of the process flow of the present invention.
FIG. 2 shows C/SiO solid films prepared in examples 1, 3 and 5 x And (3) nitrogen adsorption/desorption curve of the negative electrode material of the composite lithium battery.
FIG. 3 is a C/SiO solid prepared in examples 1, 3 and 5 x The pore diameter distribution curve diagram of the composite lithium battery negative electrode material.
FIGS. 4-7 are C/SiO solid films prepared in examples 1, 3, and 5 x The cycle performance, the coulombic efficiency of the first four turns, the multiplying power performance and the alternating current impedance diagram of the composite lithium battery negative electrode material.
FIG. 8 shows the C/SiO solid prepared in example 3 (soaking for 6 h) x -6 microscopic topography of the composite lithium battery negative electrode material.
FIG. 9 is a graph showing the particle size distribution of the low specific surface area silica microspheres prepared in examples 3, 6, 7 and 8.
FIG. 10 is a morphology of low specific surface area silica microspheres prepared in example 3.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not used as limitations of the present invention.
The test methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.
FIG. 1 is a block diagram of the process flow of the present invention, and the detailed operation of various embodiments of the present invention will be described in detail below in conjunction with the figure.
Example 1
Crushing coal gangue, and screening the crushed coal gangue through a 80-mesh screen; adding 3mol/L nitric acid solution according to the ratio of solid to liquid 1 (g: mL) to soak and remove metal impurities, filtering and separating coal gangue and acid liquor, washing the acid-leached coal gangue to be neutral by using distilled water, and obtaining pure coal gangue from which the metal impurities are removed and acid-containing washing waste liquor;
step two, adjusting the pH value of the acid liquor obtained by filtering and separating the coal gangue soaked in the step one to 3.7 by using 3mol/L KOH solution to obtain ferric hydroxide precipitate, and filtering and separating; then continuously adjusting to 4.7 to obtain aluminum hydroxide precipitate, and filtering and separating; continuously adjusting the pH value to 12 until no precipitate is generated, and separating the metal hydroxide precipitate and the alkaline waste liquid;
step three, uniformly mixing the pure coal gangue without metal impurities prepared in the step one with 3mol/L of KOH solution according to the solid-to-liquid ratio of 1 (g: mL), soaking for 4 hours at the temperature of 40 ℃, and filtering and separating to obtain a silicon-containing extracting solution and silicon-removed coal gangue;
and step four, directly drying the silicon-removed coal gangue obtained in the step three by using residual KOH as an activating agent, then putting the dried silicon-removed coal gangue into a tubular furnace using nitrogen as protective gas, and activating for 3 hours at the temperature of 700 ℃. Then, washing with distilled water and phosphoric acid to remove the activator to obtain C/SiO x Compounding a lithium battery negative electrode material and washing waste liquid;
step five, mixing the silicon-containing extracting solution prepared in the step three with distilled water and ethanol to prepare a silicon-containing diluent, wherein the volume ratio of the silicon-containing extracting solution to the distilled water to the ethanol is 1:1.5:0.5; then, dropwise adding 3mol/L nitric acid solution into the silicon-containing diluent at a dropwise adding rate of 3mL/min, enabling the pH value of the silicon-containing diluent to reach 8 under the condition that the magnetic stirring speed is 100rpm, and continuously stirring and precipitating for 4 hours; then, centrifugally separating to obtain a silicon dioxide precursor and alcohol-containing waste liquid; drying the silicon dioxide precursor in vacuum at the temperature of 90 ℃; then, calcining for 4 hours at the temperature of 550 ℃ to obtain the low-surface-area silicon dioxide microspheres;
step six, distilling the alcohol-containing waste liquid obtained in the step five to obtain alcohol-free waste liquid and ethanol; uniformly mixing the alcohol-free waste liquid, the acid-containing washing waste liquid obtained in the step one, the alkaline waste liquid obtained in the step two and the washing waste liquid obtained in the step four to be neutral to obtain a liquid compound fertilizer; then distilling to obtain a nitrogen-phosphorus-potassium compound fertilizer; and recovering the ethanol obtained by distillation for the fifth step, and recycling the distilled water for the fifth step.
Example 2
The difference between the embodiment and the embodiment 1 is that in the third step, the silicon-containing extract and the silicon-removed coal gangue are obtained by filtration and separation after soaking for 5 hours at the temperature of 40 ℃.
Example 3
The difference between the embodiment and the embodiment 1 is that in the third step, the silicon-containing extract and the silicon-removed coal gangue are obtained by filtering and separating after soaking for 6 hours at the temperature of 40 ℃.
Example 4
The difference between the embodiment and the embodiment 1 is that in the third step, the silicon-containing extract and the silicon-removed coal gangue are obtained by filtration and separation after soaking for 7 hours at the temperature of 40 ℃.
Example 5
The difference from the embodiment 1 is that in the third step, the silicon-containing extract and the silicon-removed coal gangue are obtained by filtration and separation after soaking for 8 hours at the temperature of 40 ℃.
Examples 1 to 5 comparative description
Table 1 below shows the C/SiO mixtures prepared in examples 1 to 5 x The content of each component of the composite lithium battery cathode material and O/Si, wherein C/SiO x -4，C/SiO x -5，C/SiO x -6，C/SiO x -7，C/SiO x And 8, the C/SiOx composite lithium battery negative electrode material is prepared by alkaline soaking for 4h, 5h, 6h, 7h and 8 h.
TABLE 1
As can be seen from table 1, the content of silica in the coal gangue is controlled by the duration of alkaline soaking in step three in the process of the present invention, the longer the soaking time is, the higher the relative carbon content in the coal gangue is, and the stronger the reducing power to silica is during subsequent carbonization and activation; the longer the soaking time, the smaller the O/Si, the greater the specific capacity of the material and the stronger the conductivity. However, the silicon content in the material is also a main factor for determining the electrochemical performance of the material, and the low silicon content affects the electrochemical performance of the material; therefore, under the condition of other conditions being unchanged, the C/SiO can be changed by changing the alkali soaking time x The content of each component and O/Si of the composite lithium battery negative electrode material finally changes the corresponding lithium storage capacity and electronic conductivity.
FIG. 2 shows C/SiO solid phases prepared in examples 1, 3 and 5 x The nitrogen adsorption/desorption curves of the negative electrode material of the composite lithium battery are not shown in the figures of examples 2 and 4, and the adsorption/desorption curves of the two examples are positioned in C/SiO x -6 and C/SiO x -8 or more; FIG. 3 is a C/SiO solid prepared in examples 1, 3 and 5 x The pore diameter distribution curve of the composite lithium battery negative electrode material. The following Table 2 shows examples 1-5 porous C/SiO x Pore structure parameters of the sample.
TABLE 2
Referring to FIGS. 2, 3 and Table 2, it can be seen that except for sample C/SiO x -4, N of other samples 2 The adsorption/desorption isotherm shows a point of inflection B (near point 0) in the low relative pressure (P/P0) region, which is the first steep part of the isotherm and represents the saturated adsorption capacity of the monolayer, corresponding to the completion of monolayer adsorption. As the relative pressure increases, multi-layer adsorption begins to form. In the higher P/P0 region, N 2 Capillary condensation occurs and the isotherm rises rapidly. When all the pores are agglomerated, adsorption occurs only on the outer surface much smaller than the inner surface area, and the curve is flat. When P/P0When the concentration approaches 1, the solution is adsorbed on the macropore, and the curve rises. Therefore, their isothermic curves belong to the type IV curve. When P/P0=0.4 to 0.9, an H4 hysteresis loop appears on the isothermal curve of the sample due to the occurrence of capillary coagulation, and the isothermal curve obtained at the time of desorption does not coincide with the isothermal curve obtained at the time of adsorption. This indicates that the obtained sample has a large number of large micropores or small mesopores under the activation of the residual alkali. Sample C/SiO x The isotherm of-4 is almost horizontal, which indicates that C/SiO x -4 is a less porous material.
In the alkaline soaking process, the silicon dioxide is leached from the coal gangue, a plurality of capillary pores are left on the coal gangue, the longer the soaking time is, the higher the porosity is, the more the alkali is remained, the better the activation effect on the material during carbonization and activation is, but the longer the time is, the larger the pores can cause the pore channel structure collapse of the material, therefore, the C/SiO x The specific surface area of the composite negative electrode material of the lithium battery is increased and then reduced along with the increase of the soaking time, and the pore volume is increased and then reduced along with the increase of the soaking time.
As shown in FIGS. 4 to 7, the C/SiO films prepared in examples 1, 3 and 5 were used x The cycle performance, the coulombic efficiency of the first four turns, the multiplying power performance and the alternating current impedance diagram of the composite lithium battery negative electrode material. The larger specific surface area and pore volume increase the storage capacity of lithium ions, and thus, C/SiO x The specific capacity of the lithium battery composite negative electrode material increases and then decreases with the increase of the soaking time (shown in fig. 4). C/SiO x The average pore diameter of the composite negative electrode material of the lithium battery is increased along with the increase of the soaking time, and the larger average pore diameter is beneficial to the transmission rate of lithium ions and electrons, thereby improving the C/SiO x The conductivity of the lithium battery composite negative electrode material, and therefore, the ac impedance of the material decreases with increasing soaking time (shown in fig. 7).
C/SiO x The contents of all components of the composite lithium battery cathode material, O/Si and the pore structure of the material are mutually cooperated to jointly determine C/SiO x The composite lithium battery negative electrode material has specific capacity, cycle performance, coulombic efficiency, rate capability and alternating current impedance. As previously mentioned, C/SiO x Specific capacity and cyclicity of lithium battery composite negative electrode materialEnergy, first coulombic efficiency and rate capability increase and then decrease with the increase of soaking time. Therefore, the alkaline soaking time is a main determining factor of the electrochemical performance of the C/SiOx lithium battery composite negative electrode material.
FIG. 8 shows the C/SiO solid prepared in example 3 (soaking for 6 h) x -6 micro-topography of the negative electrode material of the composite lithium battery. Porous C/SiO x 6 samples had a broad particle size distribution and many pores on the surface, which was in good agreement with the BET test results. As can be seen from the energy spectrum surface scanning picture, the three elements of C, O and Si are uniformly distributed, and the SiO is proved x The contact between the particles and the carbon skeleton is good, which not only improves the SiO x The conductivity of the particles is effectively relieved x The volume expansion and agglomeration of the particles in the charging and discharging process greatly improve the electrochemical performance of the particles. In order to observe the internal structure of a sample in detail, the invention uses a transmission scanning electron microscope to detect the sample. The results show that the nano SiO of dark color x The particles were uniformly distributed in the carbon skeleton, and SiO was not observed x The agglomeration phenomenon of the nano particles proves the analysis result of the energy spectrum surface scanning again. Selected area electron diffraction patterns of the samples, illustrating porous C/SiO x And has an amorphous structure. The amorphous carbon skeleton is uniformly wrapped with SiO x Nanoparticles, effectively improving the porosity of C/SiO x Conductivity of the sample.
Example 6
The process conditions were changed based on example 3, and the difference between this example and example 3 is that, in step five, the silicon-containing extract solution obtained in step three was mixed with distilled water and ethanol to prepare a silicon-containing diluent, specifically, the volume ratio of the silicon-containing extract solution to the distilled water to the ethanol was 1:1.5:0.5; then, dropwise adding 3mol/L nitric acid solution into the silicon-containing diluent at a dropwise adding rate of 3mL/min, enabling the pH value of the silicon-containing diluent to reach 8 under the condition that the magnetic stirring speed is 200rpm, and continuously stirring and precipitating for 4 hours; then, centrifugally separating to obtain a silicon dioxide precursor and alcohol-containing waste liquid; drying the silicon dioxide precursor in vacuum at the temperature of 90 ℃; and then, calcining for 4 hours at the temperature of 550 ℃ to obtain the low-surface-area silica microspheres. I.e. the magnetic stirring rate was changed to 200rpm.
Example 7
The process conditions were changed on the basis of example 3, which is different from example 3 in that the magnetic stirring rate was changed to 300rpm in step five.
Example 8
The process conditions were changed on the basis of example 3, which is different from example 3 in that the magnetic stirring rate was changed to 400rpm in step five.
Examples 3, 6, 7, 8 are illustrated by comparison.
FIG. 9 is a graph showing the particle size distribution of the low specific surface area silica microspheres prepared in examples 3, 6, 7 and 8. The magnetic stirring speed is a main factor for determining the particle size and the particle size distribution of the silica microspheres with a low specific surface area, and the larger the stirring speed is, the larger the particle size is, because the stirring speed is increased, the collision between the silica particles is accelerated to promote the particle size to be increased, and when the stirring speed is about 400rmin -1 The particles are broken up, and the particle size distribution is broad because the particle fraction is reduced.
FIG. 10 is a morphology of low specific surface area silica microspheres prepared in example 3. As can be seen from the SEM image and the TEM image of FIG. 10, the silica microspheres prepared by the invention are regular solid spheres, have no pore structure, have strong hydrophobicity and can be used as an additive of a hydrophobic material.
The process features of the present invention are summarized below.
Firstly, in the invention, the coal gangue is treated by acid soaking to remove metal oxides, and the obtained solid residue mainly contains amorphous carbon and silicon dioxide. Wherein, the three elements of C, si and O are uniformly distributed without a complex carbon coating process. The invention utilizes the inherent characteristics of acid treatment of the coal gangue to prepare the porous C/SiO in situ x Composite material, porous C/SiO obtained x The composite material is used as a negative electrode of a lithium ion battery.
In addition, each component in the coal gangue and each chemical reagent added are fully utilized in the process, zero emission and zero pollution are achieved, and contribution is made to high-valued comprehensive utilization of the coal gangue; the method comprises the following specific steps:
firstly, the acid soaking solution contains metal ions such as Al, fe and the like, the acid soaking solution is neutralized and precipitated by alkaline solution and is adjusted to be alkaline to obtain Al (OH) 3 、Fe(OH) 3 And waiting for the metal hydroxide to recycle the metal elements in the coal gangue. And secondly, soaking the acid-treated coal gangue with alkali, removing part of silicon dioxide in the acid-soaked coal gangue, and controlling the content of the silicon dioxide to obtain the silicon-removed coal gangue with controllable silicon dioxide content. The silicon-removed coal gangue is carbonized, activated and remolded in the pore canal of the silicon-removed coal gangue by taking residual alkali liquor as an activating agent to prepare the graded porous C/SiO x A negative electrode material for lithium batteries. The C/SiO can be effectively controlled by alkali heat soaking x Silicon content, siO, in lithium battery negative electrode materials x The content is a determining factor of the electrochemical performance of the electrode material, so that the alkaline hot soaking is one of the key technologies of the patent.
Secondly, the pore canals of the silicon-removed coal gangue are carbonized, activated and remolded by using residual alkali to obtain graded porous C/SiO x The difficulty of the method is that the activation time, the activation temperature and the residual alkali content determine C/SiO x Pore structure, each component content and Si/O of the lithium battery cathode material. Wherein, the pore channel structure, the content of each component and Si/O to C/SiO of the material x The specific capacity, the cycling stability, the rate capability, the conductivity and the first coulombic efficiency of the lithium battery cathode material are decisive, so that the unique carbonization and activation process condition is one of the key technologies of the patent.
Thirdly, if the waste liquid after the alkali-heat soaking treatment contains soluble silicate, if the soluble silicate is discharged to the nature, redundant residual alkali pollutes the environment and wastes resources, but in the invention, the low-specific-surface-area silicon dioxide is prepared by a chemical titration method, wherein the low-specific-surface-area silicon dioxide can be used as hydrophobic materials such as tooth materials, ceramic materials and the like and has high utilization value; when the low-specific-surface-area silicon dioxide is prepared, the volume ratio of distilled water, ethanol and alkali hot soaking waste liquid, the acid liquid concentration, the titration rate, the magnetic stirring rate and the pH value of a titration end point are very important to the shape, the particle size distribution and the particle size of the low-specific-surface-area silicon dioxide, and particularly, the magnetic stirring rate has a decisive effect on the particle size distribution and the particle size of the silicon dioxide and needs to be strictly controlled.
Fourthly, ethanol, nitric acid, phosphoric acid and potassium hydroxide are used in the whole production process, the substances are finally remained in washing wastewater and titration wastewater in various forms, if the substances are not recycled, the substances are directly discharged, the environment is polluted, resources are wasted, in the invention, waste liquid is collected to prepare the nitrogen-phosphorus-potassium compound fertilizer, and ethanol and distilled water are recycled, so that zero emission and zero pollution are finally realized. The prepared nitrogen-phosphorus-potassium compound fertilizer contains partial trace metal or non-metal elements in the coal gangue, and is beneficial to supplementing the requirements of plant growth on the trace elements, and partial acid-soluble organic ingredients in the coal gangue can be dissolved out during acid leaching and soaking treatment and finally enter the nitrogen-phosphorus-potassium compound fertilizer, so that the nitrogen-phosphorus-potassium compound fertilizer prepared by the invention is more beneficial to the growth and development of plants than a commercial compound fertilizer.
Although the present invention has been described in detail with reference to the foregoing examples, it will be apparent to one skilled in the art that various changes in the embodiments and/or modifications of the embodiments and/or portions thereof may be made, and all changes, equivalents, and modifications that fall within the spirit and scope of the invention are therefore intended to be embraced by the appended claims.
Claims (9)
1. A green method for comprehensively utilizing coal gangue comprises a preparation process of a C/SiOx composite lithium battery cathode material, and is characterized by comprising the following operation steps:
step 1, crushing coal gangue, soaking in acid liquor, filtering, washing to neutrality and drying;
step 2, soaking the coal gangue prepared in the step 1 in 3-5mol/L KOH solution at the temperature of 20-60 ℃ for 2-10h to remove part of silicon dioxide in the coal gangue, and then filtering and separating to obtain a silicon-containing extracting solution and silicon-removed coal gangue; the dosage is 1;
and 3, carbonizing, activating and remolding the pore channels of the silicon-removed coal gangue by using the residual KOH solution as an activator, specifically, drying the silicon-removed coal gangue prepared in the step 2, activating under the condition of using nitrogen as a protective gas, washing with distilled water and phosphoric acid, and removing the activator to obtain the C/SiOx composite lithium battery negative electrode material.
2. The green method for comprehensively utilizing the coal gangue as claimed in claim 1, wherein the green method comprises the following steps:
in the step 1, the coal gangue is crushed and screened by a screen with 60 to 100 meshes; the acid solution is 2-5mol/L nitric acid solution, and the dosage is 1-4 (g: mL) of solid-liquid; the soaking time is 12-24 h, and then the coal gangue and the acid liquor are filtered and separated; washing the acid-leached coal gangue to neutrality by using distilled water to obtain pure coal gangue with metal impurities removed and acid-containing washing waste liquid;
in the step 3, activation is carried out for 2-6h at the temperature of 600-1000 ℃; then washing with distilled water and 2-5mol/L phosphoric acid to remove the activating agent, and obtaining the C/SiOx composite lithium battery negative electrode material and washing waste liquid.
3. The green method for comprehensively utilizing the coal gangue as claimed in claim 2, wherein the green method comprises the following steps:
in the step 1, 3mol/L nitric acid solution is adopted as the acid solution, and the dosage is 1;
in the step 2, a hot alkali solution is 3mol/L KOH solution, the using amount is 1 (g: mL) of the solid-to-liquid ratio, the mixture is soaked for 4 to 8 hours at the temperature of 40 ℃, and then is filtered and separated to obtain a silicon-containing extracting solution and silicon-removed coal gangue;
in step 3, activation is carried out for 3 hours at a temperature of 700 ℃.
4. The green method for the comprehensive utilization of coal gangue as set forth in claim 2 or 3, characterized in that: the preparation process of the silicon dioxide microspheres comprises the following steps of 4:
mixing the silicon-containing extracting solution prepared in the step 2 with distilled water and ethanol to prepare a silicon-containing diluent, wherein the volume ratio of the silicon-containing diluent to the distilled water to the ethanol is 1:0.1-2:0.1 to 2; dropwise adding 2-5mol/L nitric acid solution into the silicon-containing diluent at a dropwise adding rate of 1-5mL/min, enabling the pH value of the silicon-containing diluent to reach 2-9 under the condition that the magnetic stirring speed is 100-500rpm, and continuously stirring and precipitating for 3-6h; then, centrifugally separating to obtain a silicon dioxide precursor and alcohol-containing waste liquid; drying the silicon dioxide precursor in vacuum at the temperature of 50-100 ℃; then, calcining for 3-6h at the temperature of 500-700 ℃ to obtain the low-surface-area silicon dioxide microspheres.
5. The green method for comprehensively utilizing the coal gangue as claimed in claim 4, wherein the green method comprises the following steps: in the step 4, the volume ratio of the silicon-containing extracting solution to the distilled water to the ethanol is 1:1.5:0.5; then, dropwise adding 3mol/L nitric acid solution into the silicon-containing diluent at a dropwise adding rate of 3mL/min, enabling the pH value of the silicon-containing diluent to reach 8 under the condition that the magnetic stirring speed is 100rpm, and continuously stirring and precipitating for 4 hours; then, centrifugally separating to obtain a silicon dioxide precursor and alcohol-containing waste liquid; drying the silicon dioxide precursor in vacuum at the temperature of 90 ℃; and then, calcining for 4 hours at the temperature of 550 ℃ to obtain the low-surface-area silica microspheres.
6. The green method for comprehensively utilizing the coal gangue as claimed in claim 4, wherein the green method comprises the following steps: and the method also comprises a process step 5 of gradually adding an alkali solution into the acid liquor after the coal gangue is soaked in the step 1 to separate the metal hydroxide precipitate.
7. The green method for comprehensively utilizing the coal gangue as claimed in claim 6, wherein the green method comprises the following steps: the operation method of the step 5 comprises the following steps: adjusting the pH value of the acid liquor obtained by filtering and separating the soaked coal gangue in the step 1 to 3.7 by using a KOH solution with the concentration of 3-5mol/L to obtain ferric hydroxide precipitate, and filtering and separating; then continuously adjusting to 4.7 to obtain aluminum hydroxide precipitate, and filtering and separating; and continuously adjusting the pH value to 12 until no precipitate is generated, and separating the metal hydroxide precipitate and the alkaline waste liquid.
8. The green method for comprehensively utilizing the coal gangue as claimed in claim 7, further comprising a process for recycling ethanol, and is characterized in that the following step 6 is carried out: and (4) distilling the alcohol-containing waste liquid obtained in the step (4) to obtain alcohol-free waste liquid and ethanol, and recovering the ethanol obtained by distillation for use in the step (4).
9. The green method for comprehensively utilizing the coal gangue as claimed in claim 8, further comprising a preparation process of a nitrogen-phosphorus-potassium compound fertilizer, and is characterized in that in step 7, the alcohol-free waste liquid obtained in step 6, the acid-containing washing waste liquid obtained in step 1, the alkaline waste liquid obtained in step 5, and the washing waste liquid obtained in step 3 are uniformly mixed to be neutral to obtain a liquid compound fertilizer; and distilling to obtain the nitrogen-phosphorus-potassium compound fertilizer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110306087.5A CN113003579B (en) | 2021-03-23 | 2021-03-23 | Green method for comprehensive utilization of coal gangue |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110306087.5A CN113003579B (en) | 2021-03-23 | 2021-03-23 | Green method for comprehensive utilization of coal gangue |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113003579A CN113003579A (en) | 2021-06-22 |
| CN113003579B true CN113003579B (en) | 2023-03-24 |
Family
ID=76404998
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110306087.5A Active CN113003579B (en) | 2021-03-23 | 2021-03-23 | Green method for comprehensive utilization of coal gangue |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113003579B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115196640B (en) * | 2022-07-08 | 2023-05-12 | 太原理工大学 | Gangue-based mesoporous silica material and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1334240A (en) * | 2000-07-14 | 2002-02-06 | 任忠胜 | Process for preparing super-purity alumina from gaolinite (gaolin) |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102701220A (en) * | 2012-05-22 | 2012-10-03 | 韩钊武 | Method for preparing white carbon black by oxygen-free high-temperature calcination and thermal activation of coal gangue |
| WO2015166621A1 (en) * | 2014-05-02 | 2015-11-05 | ソニー株式会社 | Battery, battery pack, electronic device, electric vehicle, electricity storage device and electric power system |
| CN105016346B (en) * | 2015-07-09 | 2017-03-08 | 大连海事大学 | A kind of green method of biomass ash comprehensive utilization |
| CN105197937A (en) * | 2015-08-17 | 2015-12-30 | 浙江大学 | Method for preparing nano white carbon black through residues generated after aluminum oxide acid leaching extraction of coal ash and slag |
| KR20170104035A (en) * | 2016-03-03 | 2017-09-14 | 동국대학교 산학협력단 | Negative electrode active material for lithium ion battery using composite of silicon comprising coal tar pitch and carbon nanofiber, and preparing method thereof |
| CN107855104B (en) * | 2017-03-16 | 2020-04-07 | 吉林大学 | Method for preparing composite mesoporous material from coal gasification coarse slag and prepared mesoporous material |
| CN108199030B (en) * | 2018-01-11 | 2020-11-03 | 南开大学 | Preparation method of porous silicon/graphite/carbon composite negative electrode material of lithium ion secondary battery |
| CN109713294B (en) * | 2018-12-12 | 2021-01-22 | 郑州中科新兴产业技术研究院 | Preparation method of silica-based negative electrode material of lithium ion battery |
| CN109841814A (en) * | 2019-02-19 | 2019-06-04 | 深圳市斯诺实业发展有限公司 | A kind of preparation method of silicon-carbon cathode material |
| CN110562952B (en) * | 2019-10-08 | 2021-02-02 | 中国矿业大学 | Process for preparing lithium secondary battery material by using coal gangue as raw material |
| CN110690439B (en) * | 2019-10-25 | 2021-11-26 | 河南大森林生物科技有限公司 | P, N co-doped C/SiO prepared from silicon-containing biomassxGreen method for composite negative electrode material of lithium ion battery |
| CN112028065B (en) * | 2020-08-25 | 2022-02-22 | 湖南宸宇富基新能源科技有限公司 | SiOx-SiC-C/G silicon-carbon composite material and preparation and application thereof |
-
2021
- 2021-03-23 CN CN202110306087.5A patent/CN113003579B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1334240A (en) * | 2000-07-14 | 2002-02-06 | 任忠胜 | Process for preparing super-purity alumina from gaolinite (gaolin) |
Non-Patent Citations (1)
| Title |
|---|
| 煤矸石制备铝系化工产品技术研究;范跃强;《煤》(第11期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113003579A (en) | 2021-06-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Cheng et al. | Separation, purification, regeneration and utilization of graphite recovered from spent lithium-ion batteries-A review | |
| CN104841365B (en) | A kind of compound defluorinating agent and preparation method | |
| CN106587046B (en) | A kind of method of purification of diamond | |
| CN113772650B (en) | Preparation method and application of lithium iron phosphate | |
| CN103030128A (en) | Industrial production method for preparing nanometer lithium iron phosphate by adopting solvent thermal method | |
| Assefi et al. | Recycling of Ni-Cd batteries by selective isolation and hydrothermal synthesis of porous NiO nanocuboid | |
| CN110980677B (en) | Method for preparing lithium iron phosphate precursor by using defective ferric phosphate | |
| CN114225938A (en) | Magnetic nano Fe3O4@ mushroom residue biochar Fenton catalyst and preparation method thereof | |
| CN111547697A (en) | Method for repairing waste lithium iron phosphate material | |
| WO2023024593A1 (en) | Method for recovering mixed waste of lithium nickel cobalt manganate and lithium iron phosphate | |
| CN113003579B (en) | Green method for comprehensive utilization of coal gangue | |
| CN109411843A (en) | A kind of regeneration method of waste and old lithium ion battery graphite electrode | |
| CN106169567B (en) | A kind of carbon-coated lithium iron phosphate positive material and preparation method thereof | |
| Zhang et al. | Green preparation of hierarchical porous C/SiOx composites from coal gangue as anodes for Li-ion batteries | |
| CN115231570B (en) | Adsorbent activated carbon particles and preparation method thereof | |
| GB2622157A (en) | Wastewater adsorbent, and preparation method therefor and use thereof | |
| CN109231215A (en) | A method of porous silicon is prepared with silicon wafer cut by diamond wire waste silicon powder | |
| CN102259872B (en) | Method for preparing white carbon black by utilizing vanadium ore waste residue | |
| CN108579670A (en) | A method of utilizing clay dephosphorization | |
| CN114146684A (en) | Modified red mud biochar material and preparation and application methods thereof | |
| CN110257851B (en) | Special electrolytic manganese dioxide for lithium manganate battery and preparation method thereof | |
| Patnaik et al. | Synthesis and characterization of fibrous nickel hydroxide obtained from spent nickel catalyst | |
| Zeng et al. | Activated carbon from Camellia oleifera shells for adsorption of Y (iii): experimental and DFT studies | |
| CN114700038B (en) | Environment functional material and preparation method and application thereof | |
| CN115463646B (en) | Salt lake brine lithium extraction adsorption material and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |