Beneficiation purification method of high-purity graphite

Abstract

This invention belongs to the field of graphite beneficiation and purification technology, specifically relating to a method for beneficiating and purifying high-purity graphite. The method provided by this invention includes the following steps: crushing and screening raw graphite ore, preparing the slurry, and roughing the slurry. During the roughing process, diesel oil, modified terpene resin, sodium dodecylbenzenesulfonate, and 2-octanol are added to obtain a rough concentrate and tailings. The rough concentrate is regrinded and subjected to a first cleaning process to obtain a first-cleaned concentrate. The first-cleaned concentrate is regrinded and subjected to a second cleaning process, during which diesel oil, modified terpene resin, sodium dodecylbenzenesulfonate, and 2-octanol are added to obtain a second-cleaned concentrate. The second-cleaned concentrate is regrinded and subjected to a third cleaning process, during which diesel oil, modified terpene resin, sodium dodecylbenzenesulfonate, and 2-octanol are added to obtain a graphite concentrate. This invention can improve the grade of graphite concentrate while increasing its recovery rate.

Description

Technical Field

[0001] This invention belongs to the field of graphite beneficiation and purification technology, specifically relating to a method for beneficiating and purifying high-purity graphite. Background Technology

[0002] Graphite, as a non-metallic mineral resource, is a fundamental raw material for many industries. It possesses excellent thermal conductivity, radiation resistance, lubrication, and electrical conductivity, and is widely used in automobiles, energy storage, national defense, and electronic information fields. Natural graphite is generally classified into three categories: dense crystalline graphite, cryptocrystalline graphite, and flake graphite. High-grade graphite concentrate can be obtained through processes such as grinding and flotation. Among these, flake graphite is mostly natural phanerocrystalline graphite, exhibiting a flake-like structure resembling fish scales, and its value increases with size. Therefore, the beneficiation and purification of flake graphite is of great significance.

[0003] Current methods for purifying graphite ore generally employ flotation, a process typically including rough grinding, roughing, and cleaning. However, to obtain high-grade graphite concentrate, it is often necessary to increase the number of cleaning stages, which in turn leads to a decrease in recovery rate. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the shortcomings of existing graphite beneficiation and purification methods that cannot simultaneously achieve high concentrate grade and recovery rate, thereby providing a beneficiation and purification method for high-purity graphite.

[0005] To solve the above problems, the present invention provides the following solution:

[0006] A method for beneficiating and purifying high-purity graphite includes the following steps:

[0007] 1) The graphite ore is crushed and screened, and the screened material is slurryed and roughed. During the roughing process, diesel oil, modified terpene resin, sodium dodecylbenzene sulfonate and 2-octanol are added to obtain rough concentrate and tailings.

[0008] 2) The rough concentrate is regrinded, and the regrinded slurry is subjected to the first cleaning process to obtain the first cleaned concentrate;

[0009] 3) The first-selected concentrate is regrinded, and the regrinded slurry is then subjected to a second-selection process. During the second-selection process, diesel oil, modified terpene resin, sodium dodecylbenzene sulfonate, and 2-octanol are added to obtain the second-selected concentrate.

[0010] 4) The second-selected concentrate is regrinded, and the regrinded slurry is then subjected to a third-selection process. During the third-selection process, diesel oil, modified terpene resin, sodium dodecylbenzene sulfonate, and 2-octanol are added to obtain graphite concentrate.

[0011] Preferably, the preparation method of the modified terpene resin includes the following steps:

[0012] α-pinene, catalyst, and solvent are mixed and reacted. Then, vinyltrimethoxysilane and ethyl acrylate are added to the reaction solution, and the reaction continues. After the reaction is complete, hot water is added to the reaction solution, stirred, and allowed to stand to separate the layers. The organic phase is then separated to obtain the modified terpene resin.

[0013] The α-pinene described in this invention can be made from high-purity α-pinene raw materials or from production waste containing α-pinene, as long as it contains a high content of α-pinene.

[0014] Preferably, in the preparation method of the modified terpene resin, the mass ratio of α-pinene, catalyst and solvent is 10:(1-5):(100-200).

[0015] Preferably, in the preparation method of the modified terpene resin, the reaction temperature is -10℃ to 0℃, the reaction time is 0.5 to 1h, and the reaction continues at -10℃ to 0℃ for 1 to 3h.

[0016] Preferably, in the preparation method of the modified terpene resin, the mass ratio of α-pinene, vinyltrimethoxysilane and ethyl acrylate is 10:(3-5):(3-5).

[0017] Preferably, in the preparation method of the modified terpene resin, the mass ratio of the solvent to hot water is 1:(1-3), and the hot water is hot water at 50-70℃;

[0018] The stirring time is 0.5-2 hours;

[0019] The catalyst is aluminum trichloride, and the solvent is toluene.

[0020] Preferred,

[0021] In step 1), the fineness of the material after screening is -0.082mm, the content is 50-55%, the slurry concentration is 15-20%, and the coarse selection concentration is 7-10%.

[0022] In step 1), the amount of diesel fuel used is 300-400 g / t, the amount of modified terpene resin used is 20-40 g / t, the amount of sodium dodecylbenzenesulfonate used is 40-60 g / t, and the amount of 2-octanol used is 300-350 g / t.

[0023] Preferred,

[0024] In step 2), the regrinding concentration is 35-40%, the grinding fineness is -0.082mm and the content is 70-75%, and the flotation concentration in the first cleaning is 7-7.5%.

[0025] In step 2), the first selection process does not include diesel fuel, modified terpene resin, sodium dodecylbenzene sulfonate, and 2-octanol.

[0026] Preferred,

[0027] In step 3), the regrinding concentration is 30-35%, the grinding fineness is -0.082mm and the content is 83-87%, and the flotation concentration in the second cleaning is 6-6.5%.

[0028] In step 3), the amount of diesel fuel used is 300-400 g / t, the amount of modified terpene resin used is 20-40 g / t, the amount of sodium dodecylbenzenesulfonate used is 40-60 g / t, and the amount of 2-octanol used is 300-350 g / t.

[0029] Preferred,

[0030] In step 4), the regrinding concentration is 25-30%, the grinding fineness is -0.082mm and the content is 85-90%, and the flotation concentration in the third cleaning is 4-5.5%.

[0031] In step 4), the amount of diesel fuel used is 300-400 g / t, the amount of modified terpene resin used is 20-40 g / t, the amount of sodium dodecylbenzenesulfonate used is 40-60 g / t, and the amount of 2-octanol used is 300-350 g / t.

[0032] The technical solution of this invention has the following advantages:

[0033] The present invention provides a method for beneficiating and purifying high-purity graphite. This method involves adding diesel oil, modified terpene resin, sodium dodecylbenzenesulfonate, and 2-octanol during the roughing, second cleaning, and third cleaning processes. The addition of the modified terpene resin, a collector aid, is particularly important. Terpene resin has a certain degree of viscosity, which is unfavorable for dispersion. The present invention first prepolymerizes α-pinene, then adds vinyltrimethoxysilane and ethyl acrylate to form a block polymer. The addition of the trimethoxysilane block reduces the viscosity of the terpene resin and improves the wettability of the graphite ore. By adding the modified terpene resin organic phase solution, the present invention enhances the adhesion of diesel oil to the graphite ore surface. Simultaneously, the combination of sodium dodecylbenzenesulfonate and 2-octanol improves the hydrophobicity and wettability of the graphite ore surface, thereby increasing the grade and recovery rate of the graphite concentrate and significantly improving economic benefits. Detailed Implementation

[0034] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0035] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0036] Example 1

[0037] This embodiment provides a method for beneficiation and purification of high-purity graphite, including the following steps:

[0038] 1) The fine flake graphite ore (grade 6%) is crushed and screened. The undersize material (-0.082mm content 51.3%) is slurryed (concentration 20%). The slurry is roughed to a concentration of 8.14%. During the roughing process, diesel oil (350g / t), modified terpene resin (30g / t), sodium dodecylbenzene sulfonate (50g / t), and 2-octanol (300g / t) are added to obtain rough concentrate and tailings.

[0039] 2) The rough concentrate is regrinded to a concentration of 36.5% and a grinding fineness of -0.082mm with a content of 74.3%; the regrinded slurry is then subjected to a first cleaning process with a flotation concentration of 7.25%. No diesel oil, modified terpene resin, sodium dodecylbenzene sulfonate, or 2-octanol are added during the first cleaning process to obtain the first-cleaned concentrate and middlings.

[0040] 3) The first-stage concentrate is regrinded to a concentration of 31.6% and a fineness of -0.082mm with a content of 86.1%. The regrinded slurry is then subjected to a second-stage cleaning process with a flotation concentration of 6.15%. During the second-stage cleaning process, diesel oil (350g / t), modified terpene resin (30g / t), sodium dodecylbenzene sulfonate (50g / t), and 2-octanol (300g / t) are added to obtain the second-stage concentrate and middlings.

[0041] 4) The second-stage concentrate was regrinded to a concentration of 28.4% and a fineness of -0.082 mm with a content of 87.8%. The regrinded slurry was then subjected to a third-stage cleaning process with a flotation concentration of 4.24%. During the third-stage cleaning process, diesel oil (350 g / t), modified terpene resin (30 g / t), sodium dodecylbenzene sulfonate (50 g / t), and 2-octanol (300 g / t) were added to obtain graphite concentrate. The grade of the graphite concentrate product was 93%, and the recovery rate was 84%.

[0042] The preparation method of the modified terpene resin includes the following steps:

[0043] 10g of α-pinene, 3g of aluminum trichloride and 150g of toluene were mixed and reacted at 0℃ for 1h. Then, 5g of vinyltrimethoxysilane and 5g of ethyl acrylate were added dropwise to the reaction solution, and the reaction was continued at 0℃ for 2h. After the reaction was completed, 200g of 50℃ hot water was added to the reaction solution, stirred for 0.5h, allowed to stand and separate into layers, and the organic phase was separated to obtain the modified terpene resin.

[0044] Example 2

[0045] This embodiment provides a method for beneficiation and purification of high-purity graphite, including the following steps:

[0046] 1) The fine flake graphite ore (grade 6%) is crushed and screened. The undersize material (-0.082mm content 51.3%) is slurryed (concentration 20%). The slurry is roughed to a concentration of 8.14%. During the roughing process, diesel oil (400g / t), modified terpene resin (40g / t), sodium dodecylbenzene sulfonate (50g / t), and 2-octanol (350g / t) are added to obtain rough concentrate and tailings.

[0047] 2) The rough concentrate is regrinded to a concentration of 36.5% and a grinding fineness of -0.082mm with a content of 74.3%; the regrinded slurry is then subjected to a first cleaning process with a flotation concentration of 7.12%. No diesel oil, modified terpene resin, sodium dodecylbenzene sulfonate, or 2-octanol are added during the first cleaning process to obtain the first-cleaned concentrate and middlings.

[0048] 3) The first-stage concentrate is regrinded to a concentration of 32.3% and a fineness of -0.082mm with a content of 87.3%. The regrinded slurry is then subjected to a second-stage cleaning process with a flotation concentration of 6.41%. During the second-stage cleaning process, diesel oil (400g / t), modified terpene resin (40g / t), sodium dodecylbenzene sulfonate (50g / t), and 2-octanol (350g / t) are added to obtain the second-stage concentrate and middlings.

[0049] 4) The second-stage concentrate was regrinded to a concentration of 29.1% and a fineness of -0.082 mm with a content of 88.2%. The regrinded slurry was then subjected to a third-stage cleaning process with a flotation concentration of 4.01%. During the third-stage cleaning process, diesel oil (400 g / t), modified terpene resin (40 g / t), sodium dodecylbenzene sulfonate (50 g / t), and 2-octanol (350 g / t) were added to obtain graphite concentrate. The grade of the graphite concentrate product was 95%, and the recovery rate was 86%.

[0050] The preparation method of the modified terpene resin includes the following steps:

[0051] 10g of α-pinene, 3g of aluminum trichloride and 150g of toluene were mixed and reacted at 0℃ for 1h. Then, 6g of vinyltrimethoxysilane and 4g of ethyl acrylate were added dropwise to the reaction solution, and the reaction was continued at 0℃ for 2h. After the reaction was completed, 200g of 50℃ hot water was added to the reaction solution, stirred for 0.5h, allowed to stand and separate into layers, and the organic phase was separated to obtain the modified terpene resin.

[0052] Comparative Example 1

[0053] This comparative example provides a method for beneficiation and purification of high-purity graphite, which differs from Example 1 in that the preparation method of the modified terpene resin includes the following steps:

[0054] 10g of α-pinene, 3g of aluminum trichloride, and 150g of toluene were mixed and reacted at 0℃ for 1h. Then, 5g of ethyl acrylate was added dropwise to the reaction solution, and the reaction was continued at 0℃ for 2h. After the reaction was completed, 200g of hot water at 50℃ was added to the reaction solution, and the mixture was stirred for 0.5h. After standing and separating the layers, the organic phase was separated to obtain the modified terpene resin. The grade of the prepared graphite concentrate product was 86%, and the recovery rate was 81%.

[0055] Comparative Example 2

[0056] This comparative example provides a method for beneficiation and purification of high-purity graphite, which differs from Example 1 in that the preparation method of the modified terpene resin includes the following steps:

[0057] 10g of α-pinene, 3g of aluminum trichloride, and 150g of toluene were mixed and reacted at 0℃ for 1h. Then, 5g of vinylcyclohexane and 5g of ethyl acrylate were added dropwise to the reaction solution, and the reaction was continued at 0℃ for 2h. After the reaction was completed, 200g of hot water at 50℃ was added to the reaction solution, and the mixture was stirred for 0.5h. After standing and separating the layers, the organic phase was separated to obtain the modified terpene resin. The grade of the prepared graphite concentrate product was 90%, and the recovery rate was 79%.

[0058] Comparative Example 3

[0059] This comparative example provides a method for beneficiation and purification of high-purity graphite, comprising the following steps:

[0060] 1) The fine flake graphite ore (grade 6%) is crushed and screened. The undersize material (-0.082mm content 51.3%) is slurryed (concentration 20%). The slurry is roughed to a concentration of 8.14%. During the roughing process, diesel oil (350g / t), sodium dodecylbenzenesulfonate (50g / t) and 2-octanol (300g / t) are added to obtain rough concentrate and tailings.

[0061] 2) The rough concentrate is regrinded to a concentration of 36.5% and a grinding fineness of -0.082mm with a content of 74.3%; the regrinded slurry is then subjected to a first cleaning process with a flotation concentration of 7.25%. No diesel oil, sodium dodecylbenzenesulfonate, or 2-octanol are added during the first cleaning process to obtain the first-cleaned concentrate and middlings.

[0062] 3) The first-stage concentrate is regrinded to a concentration of 31.6% and a fineness of -0.082mm with a content of 86.1%. The regrinded slurry is then subjected to a second-stage cleaning process with a flotation concentration of 6.15%. During the second-stage cleaning process, diesel oil (350g / t), sodium dodecylbenzenesulfonate (50g / t), and 2-octanol (300g / t) are added to obtain the second-stage concentrate and middlings.

[0063] 4) The second-stage concentrate is regrinded to a concentration of 28.4% and a fineness of -0.082 mm with a content of 87.8%. The regrinded slurry is then subjected to a third-stage cleaning process with a flotation concentration of 4.24%. During the third-stage cleaning process, diesel oil (350 g / t), sodium dodecylbenzenesulfonate (50 g / t), and 2-octanol (300 g / t) are added to obtain graphite concentrate. The grade of the graphite concentrate product is 80%, and the recovery rate is 75%.

[0064] Comparative Example 4

[0065] This comparative example provides a method for beneficiation and purification of high-purity graphite, comprising the following steps:

[0066] 1) The fine flake graphite ore (grade 6%) is crushed and screened. The undersize material (-0.082mm content 51.3%) is slurryed (concentration 20%). The slurry is roughed to a concentration of 8.14%. During the roughing process, diesel oil (350g / t), turpentine oil (30g / t), sodium dodecylbenzenesulfonate (50g / t) and 2-octanol (300g / t) are added to obtain rough concentrate and tailings.

[0067] 2) The rough concentrate is regrinded to a concentration of 36.5% and a grinding fineness of -0.082mm with a content of 74.3%; the regrinded slurry is then subjected to a first cleaning process with a flotation concentration of 7.25%. No diesel oil, turpentine, sodium dodecylbenzene sulfonate, or 2-octanol are added during the first cleaning process to obtain the first-cleaned concentrate and middlings.

[0068] 3) The first-stage concentrate is regrinded to a concentration of 31.6% and a fineness of -0.082mm with a content of 86.1%. The regrinded slurry is then subjected to a second-stage cleaning process with a flotation concentration of 6.15%. During the second-stage cleaning process, diesel oil (350g / t), turpentine (30g / t), sodium dodecylbenzenesulfonate (50g / t), and 2-octanol (300g / t) are added to obtain the second-stage concentrate and middlings.

[0069] 4) The second-stage concentrate was regrinded to a concentration of 28.4% and a fineness of -0.082 mm with a content of 87.8%. The regrinded slurry was then subjected to a third-stage cleaning process with a flotation concentration of 4.24%. During the third-stage cleaning process, diesel oil (350 g / t), turpentine (30 g / t), sodium dodecylbenzenesulfonate (50 g / t), and 2-octanol (300 g / t) were added to obtain graphite concentrate. The grade of the graphite concentrate product was 83%, and the recovery rate was 77%.

[0070] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for beneficiating and purifying high-purity graphite, characterized in that, Includes the following steps: 1) The graphite ore is crushed and screened, and the screened material is slurryed and roughed. During the roughing process, diesel oil, modified terpene resin, sodium dodecylbenzene sulfonate and 2-octanol are added to obtain rough concentrate and tailings. 2) The rough concentrate is regrinded, and the regrinded slurry is subjected to the first cleaning process to obtain the first cleaned concentrate; 3) The first-selected concentrate is regrinded, and the regrinded slurry is then subjected to a second-selection process. During the second-selection process, diesel oil, modified terpene resin, sodium dodecylbenzene sulfonate, and 2-octanol are added to obtain the second-selected concentrate. 4) The second-selected concentrate is regrinded, and the regrinded slurry is then subjected to a third-selection process. During the third-selection process, diesel oil, modified terpene resin, sodium dodecylbenzene sulfonate, and 2-octanol are added to obtain graphite concentrate. The preparation method of the modified terpene resin includes the following steps: α-pinene, catalyst, and solvent are mixed and reacted. Then, vinyltrimethoxysilane and ethyl acrylate are added to the reaction solution, and the reaction continues. After the reaction is complete, hot water is added to the reaction solution, stirred, and allowed to stand to separate the layers. The organic phase is then separated to obtain the modified terpene resin.

2. The method for beneficiation and purification of high-purity graphite according to claim 1, characterized in that, In the preparation method of the modified terpene resin, the mass ratio of α-pinene, catalyst and solvent is 10:1-5:100-200.

3. The method for beneficiation and purification of high-purity graphite according to claim 1, characterized in that, In the preparation method of the modified terpene resin, the reaction temperature after mixing is -10℃ to 0℃, and the reaction time is 0.5 to 1h; the reaction temperature continues to be -10℃ to 0℃, and the reaction time continues to be 1 to 3h.

4. The method for beneficiation and purification of high-purity graphite according to claim 1, characterized in that, In the preparation method of the modified terpene resin, the mass ratio of α-pinene, vinyltrimethoxysilane and ethyl acrylate is 10:3-5:3-5.

5. The method for beneficiation and purification of high-purity graphite according to claim 1, characterized in that, In the preparation method of the modified terpene resin, the mass ratio of solvent to hot water is 1:1-3, and the hot water is hot water at 50-70℃. The stirring time is 0.5-2 hours; The catalyst is aluminum trichloride, and the solvent is toluene.

6. The method for beneficiation and purification of high-purity graphite according to claim 1, characterized in that, In step 1), the fineness of the material after screening is -0.082mm, the content is 50-55%, the slurry concentration is 15-20%, and the coarse selection concentration is 7-10%. In step 1), the amount of diesel fuel used is 300-400 g / t, the amount of modified terpene resin used is 20-40 g / t, the amount of sodium dodecylbenzenesulfonate used is 40-60 g / t, and the amount of 2-octanol used is 300-350 g / t.

7. The method for beneficiation and purification of high-purity graphite according to claim 1, characterized in that, In step 2), the regrinding concentration is 35-40%, the grinding fineness is -0.082mm and the content is 70-75%, and the flotation concentration in the first cleaning is 7-7.5%. In step 2), the first selection process does not include diesel fuel, modified terpene resin, sodium dodecylbenzene sulfonate, and 2-octanol.

8. The method for beneficiation and purification of high-purity graphite according to claim 1, characterized in that, In step 3), the regrinding concentration is 30-35%, the grinding fineness is -0.082mm and the content is 83-87%, and the flotation concentration in the second cleaning is 6-6.5%. In step 3), the amount of diesel fuel used is 300-400 g / t, the amount of modified terpene resin used is 20-40 g / t, the amount of sodium dodecylbenzenesulfonate used is 40-60 g / t, and the amount of 2-octanol used is 300-350 g / t.

9. The method for beneficiation and purification of high-purity graphite according to claim 1, characterized in that, In step 4), the regrinding concentration is 25-30%, the grinding fineness is -0.082mm and the content is 85-90%, and the flotation concentration in the third cleaning is 4-5.5%. In step 4), the amount of diesel fuel used is 300-400 g / t, the amount of modified terpene resin used is 20-40 g / t, the amount of sodium dodecylbenzenesulfonate used is 40-60 g / t, and the amount of 2-octanol used is 300-350 g / t.