Volcanic stone graphene adsorption material, preparation method and application thereof

Abstract

This invention relates to the field of wastewater treatment, and discloses a volcanic rock graphene adsorbent material, its preparation method, and its application. The volcanic rock graphene adsorbent material comprises a volcanic rock matrix and carbon, with some carbon existing in the form of graphene. Based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.12-0.5% by weight, and the volcanic rock matrix content is 99.5-99.88% by weight. The volcanic rock graphene adsorbent material provided by this invention has high adsorption efficiency, can be regenerated and reused multiple times, and its performance remains stable after multiple uses, greatly improving the service life of the adsorbent material.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment, specifically to a volcanic rock graphene adsorbent material, its preparation method, and its application. Background Technology

[0002] With rapid social and economic development, marine oil spills and oily wastewater discharges have caused enormous damage to the economy and environment, and water pollution caused by oil spills and industrial oil pollution is becoming increasingly serious. Among the methods for dealing with these problems, adsorption is an effective and simple way to solve marine oil spills because it can adsorb floating oil into solid or semi-solid materials, thereby removing the floating oil. Adsorption is considered one of the most economical, efficient, and environmentally friendly methods. Therefore, synthesizing new adsorbent materials with high adsorption performance is of great practical significance for treating oil pollution problems. Generally speaking, excellent adsorbent materials should have high adsorption capacity, hydrophobicity and oleophilicity, and reusability. To avoid secondary pollution from adsorbent materials, new adsorbent materials should have a certain degree of biodegradability to avoid secondary pollution to the environment. However, traditional adsorbent materials have shortcomings in terms of high adsorption capacity, hydrophobicity and oleophilicity, and reusability.

[0003] Adsorption separation technology is commonly used for wastewater treatment due to its simplicity and low cost, leading to its widespread application in industry. The adsorbent material is the core and key component of adsorption separation technology. Traditional adsorbents possess characteristics such as high porosity, high surface hydrophobicity, and oleophilicity, resulting in excellent oil absorption performance. Currently, commonly used adsorbent materials include activated carbon and other materials with high porosity and high specific surface area. However, while activated carbon offers good adsorption performance, its inability to be reused leads to high adsorption separation costs. Furthermore, the adsorption efficiency, unit adsorption capacity, and continuous service life of existing adsorbent materials still require further improvement. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this invention provides a volcanic rock graphene adsorbent material, its preparation method, and its application. This adsorbent material has advantages such as high adsorption efficiency, regeneration and reuse, long continuous service life, and low cost.

[0005] To achieve the above objectives, the present invention provides a volcanic rock graphene adsorbent material, wherein the volcanic rock graphene adsorbent material comprises a volcanic rock matrix and graphene, and some carbon exists in the form of graphene.

[0006] Based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.12-0.5% by weight, and the volcanic rock matrix content is 99.5-99.88% by weight.

[0007] The average pore size of the volcanic rock graphene adsorbent material is 0.3-1.7 mm.

[0008] A second aspect of this invention provides a method for preparing a volcanic rock graphene adsorbent material, comprising the following steps:

[0009] (1) Glucose and / or its derivatives, allyl alcohol, organic acids and solvents are mixed to obtain a mixture;

[0010] (2) The volcanic rock matrix is ​​impregnated in the mixture, and then the resulting solid material is dried and calcined in an oxygen-free environment.

[0011] The third aspect of this invention provides a volcanic rock graphene adsorbent material prepared by the method described in the second aspect.

[0012] The fourth aspect of this invention provides an application of the volcanic rock graphene adsorbent material described in the first or third aspect in the treatment of oily wastewater.

[0013] The beneficial effects of this invention include:

[0014] (1) The volcanic rock graphene adsorbent material provided by the present invention has high adsorption efficiency, can be regenerated and reused multiple times, and its performance remains stable after multiple uses, which greatly improves the service life of the adsorbent material.

[0015] (2) This invention uses waste volcanic rock as a matrix to prepare volcanic rock graphene electrodes, realizing the rational and efficient recycling of waste volcanic rock, with a wider range of applications, environmental friendliness, and higher economic benefits.

[0016] (3) The preparation process of the volcanic rock graphene adsorbent material provided by the present invention is simple. The volcanic rock graphene adsorbent material obtained by impregnating volcanic rock with glucose and / or its derivatives, polyols and organic acids and then calcining it in an anaerobic environment has a more uniform graphene dispersion, a lower preparation cost and a wider range of applications compared with the direct combination of volcanic rock and graphene finished product. Attached Figure Description

[0017] Figure 1 This is the Raman spectrum of the adsorbent material A1 prepared in Example 1;

[0018] Figure 2 This is a graph showing the change in oil content in the system when the adsorbent materials A1-A5 prepared in Examples 1-5 are applied to a simulated oily wastewater treatment experiment;

[0019] Figure 3 This is a graph showing the change in oil content in the system when the adsorbent materials D1-D4 prepared in Comparative Examples 1-4 and volcanic rock were applied to simulated oily wastewater treatment experiments.

[0020] Figure 4The graph shows the data results of 10 consecutive treatments of simulated oily wastewater using adsorbent material A1 prepared in Example 1. Detailed Implementation

[0021] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0022] The present invention provides a volcanic rock graphene adsorbent material, wherein the volcanic rock graphene adsorbent material comprises a volcanic rock matrix and carbon, and some of the carbon exists in the form of graphene.

[0023] Based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.12-0.5% by weight, and the volcanic rock matrix content is 99.5-99.88% by weight.

[0024] The average pore size of the volcanic rock graphene adsorbent material is 0.3-1.7 mm.

[0025] According to the present invention, preferably, the carbon content is 0.15-0.5% by weight and the volcanic rock matrix content is 99.5-99.85% by weight, based on the total weight of the volcanic rock graphene adsorbent material.

[0026] According to the present invention, the content of volcanic rock matrix and carbon in volcanic rock graphene adsorbent material is determined by weighing and calculating the weight difference before and after calcination.

[0027] According to the present invention, preferably, the average pore size of the volcanic rock graphene adsorbent material is 0.3-1.5 mm.

[0028] According to the present invention, preferably, the specific surface area of ​​the volcanic rock graphene adsorbent material is 0.5-5 cm². 2 / g, preferably 2-5m 2 / g.

[0029] According to the present invention, preferably, the porosity of the volcanic rock graphene adsorbent material is 30-70%, more preferably 30-60%.

[0030] The average pore size, specific surface area, and porosity of the volcanic rock graphene adsorbent material described in this invention were determined using a nitrogen adsorption-desorption method.

[0031] A second aspect of this invention provides a method for preparing a volcanic rock graphene adsorbent material, comprising the following steps:

[0032] (1) Glucose and / or its derivatives, polyols, organic acids and solvents are mixed to obtain a mixture;

[0033] (2) The volcanic rock matrix is ​​impregnated in the mixture, and then the resulting solid material is dried and calcined in an oxygen-free environment.

[0034] According to the present invention, preferably, the weight ratio of glucose and / or its derivatives, polyol, organic acid, and solvent is 2-10:2-10:1-10:100, more preferably 3-5:3-5:5-8:100. Using this preferred embodiment, the adsorption effect of the adsorbent material is optimal.

[0035] According to the present invention, preferably, the concentration of glucose and / or its derivatives is 2-10 wt%, more preferably 3-5 wt%.

[0036] According to the present invention, preferably, the concentration of the polyol is 2-10 wt%, more preferably 3-5 wt%.

[0037] According to the present invention, preferably, the concentration of the organic acid is 1-10 wt%, more preferably 5-8 wt%. Using this preferred embodiment, the adsorption effect of the adsorbent material is optimal.

[0038] The present invention allows for a wide range of selection of the glucose derivatives. Preferably, the glucose derivative is sodium gluconate and / or potassium gluconate, and more preferably sodium gluconate. This preferred embodiment requires a small dosage, achieves good loading effect, and is inexpensive and readily available.

[0039] The polyol used in this invention can further improve the carbon loading capacity. Preferably, the polyol is a C2-C5 alcohol, and more preferably selected from at least one of allyl alcohol, ethylene glycol, glycerol, and isopropanol.

[0040] The organic acid used in this invention not only facilitates a stronger bond between the mixture and the volcanic rock matrix, but also results in a more uniform dispersion of the mixture on the volcanic rock matrix. Preferably, the organic acid is tartaric acid and / or malic acid, with tartaric acid being more preferred.

[0041] According to the present invention, preferably, the solvent is water and / or an organic solvent. To improve the impregnation effect of the volcanic rock, the solvent is preferably water.

[0042] In a preferred embodiment, the glucose and / or its derivatives, polyols, and organic acids used in this invention have a purity of 99% or higher, preferably 99.5% or higher.

[0043] This invention does not impose any particular limitation on the mixing method of the glucose and / or its derivatives, polyols, organic acids, and solvents; they can be added together or separately, as long as thorough mixing is achieved. For example, glucose and / or its derivatives, polyols, and organic acids can be added together to the solvent.

[0044] The present invention does not have any particular limitation on the mixing in step (1), and can be carried out with reference to conventional technical means in the field.

[0045] Preferably, the mixing in step (1) is carried out under stirring conditions. The present invention does not impose any particular limitation on the stirring speed and time, which can be appropriately selected according to specific circumstances, as long as the mixture is homogeneous.

[0046] This invention does not have any particular limitation on the source of volcanic rock; it can be volcanic rock obtained by various existing methods.

[0047] According to the present invention, preferably, the amount of the mixture and the volcanic rock matrix is ​​such that, based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.12-0.5% by weight and the volcanic rock matrix content is 99.5-99.88% by weight.

[0048] According to the present invention, preferably, the amounts of the mixture and the volcanic rock matrix are such that, based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.15-0.5% by weight and the volcanic rock matrix content is 99.5-99.85% by weight.

[0049] According to the present invention, preferably, the conditions for impregnation in step (2) include: a temperature of 20-40°C and a time of 2-10 hours.

[0050] According to the present invention, preferably, the impregnation method is equal volume impregnation or excessive impregnation, more preferably equal volume impregnation.

[0051] The present invention does not particularly limit the method of obtaining the solid material, and it can be obtained using techniques commonly used in the art. Preferably, the solid material is obtained by suspension; once the liquid stops dripping (the crystals are completely adhered to the material), the next step can be performed.

[0052] According to the present invention, preferably, the drying conditions in step (2) include: a temperature of 80-120°C and a time of 12-24h.

[0053] According to the present invention, preferably, the conditions for the oxygen-free calcination in step (2) include: a calcination temperature of 800-1200℃ and a calcination time of 2-6 hours. This preferred embodiment is beneficial for the formation of graphene.

[0054] According to the present invention, preferably, the heating rate of the anaerobic calcination is 5-20℃ / min, more preferably 5-10℃ / min. This preferred embodiment effectively avoids both the loss of the desired product and the formation of stable intermediate products.

[0055] According to one specific embodiment of the present invention, the oxygen-free calcination is carried out under vacuum conditions.

[0056] The third aspect of this invention provides a volcanic rock graphene adsorbent material prepared by the method described in the second aspect.

[0057] The fourth aspect of this invention provides an application of the volcanic rock graphene adsorbent material described in the first or third aspect in the treatment of oily wastewater.

[0058] Preferably, the volcanic rock graphene adsorbent material is used to treat oily wastewater with an oil concentration of 130-160 mg / L.

[0059] The volcanic rock graphene adsorbent material provided by this invention can be regenerated and reused multiple times, and its adsorption effect is stable. Here, "regeneration" refers to drying the adsorbent material, preferably at 80-120℃ for 8-24 hours.

[0060] The present invention will be described in detail below through embodiments.

[0061] In the following embodiments, the Raman spectra of the adsorbent material were measured using a Raman spectrometer. Specific test conditions were: wavelength 532 nm; objective lens magnification 50x, numerical aperture 0.35, focal length 3.6 mm; spectrometer grating 1800 mm. -1 The incident slit is 10μm, and the CCD is 1024×256.

[0062] The reagents used in the following examples are commercially available and of analytical grade.

[0063] Example 1

[0064] (1) Weigh allyl alcohol, sodium gluconate, tartaric acid and water in a mass ratio of 3:3:5:100, then dissolve allyl alcohol, sodium gluconate and tartaric acid in water and stir until homogeneous to obtain a mixture.

[0065] (2) The volcanic rock matrix was immersed in the mixed solution at an equal volume for 2 hours at a temperature of 25°C. After immersion, the volcanic rock matrix was removed, hung to dry to remove excess solution, and then placed in an oven to dry at 90°C for 24 hours. The dried volcanic rock matrix was then placed in a muffle furnace for oxygen-free calcination under vacuum conditions, with the temperature increased to 1000°C at a rate of 10°C / min and maintained for 4 hours to obtain volcanic rock graphene adsorbent material A1. The specific parameters are shown in Table 1.

[0066] The Raman spectrum of volcanic rock graphene adsorbent material A1 is given as an example, such as Figure 1 As shown, graphene materials with different numbers of layers can be observed and compared.

[0067] Example 2

[0068] (1) Weigh allyl alcohol, sodium gluconate, malic acid and water in a mass ratio of 5:5:5:100, then dissolve allyl alcohol, sodium gluconate and malic acid in water and stir until uniform to obtain a mixture.

[0069] (2) The volcanic rock matrix was immersed in the mixed solution at an equal volume for 2 hours at a temperature of 25°C. After immersion, the volcanic rock matrix was removed, hung to dry to remove excess solution, and then placed in an oven to dry at 90°C for 24 hours. The dried volcanic rock matrix was then placed in a muffle furnace for oxygen-free calcination under vacuum conditions, with the temperature increased to 1000°C at a rate of 10°C / min and maintained for 4 hours to obtain volcanic rock graphene adsorbent material A2. The specific parameters are shown in Table 1.

[0070] Example 3

[0071] (1) Weigh out glycerol, sodium gluconate, tartaric acid and water in a mass ratio of 5:3:8:100, then dissolve glycerol, sodium gluconate and tartaric acid in water and stir until homogeneous to obtain a mixture.

[0072] (2) The volcanic rock matrix was immersed in the mixed solution at an equal volume for 2 hours at a temperature of 25°C. After immersion, the volcanic rock matrix was removed, hung to dry to remove excess solution, and then placed in an oven to dry at 90°C for 24 hours. The dried volcanic rock matrix was then placed in a muffle furnace for oxygen-free calcination under vacuum conditions, with the temperature increased to 1000°C at a rate of 8°C / min and maintained for 4 hours to obtain volcanic rock graphene adsorbent material A3. The specific parameters are shown in Table 1.

[0073] Example 4

[0074] (1) Weigh allyl alcohol, sodium gluconate, tartaric acid and water in a mass ratio of 3:5:8:100, then dissolve allyl alcohol, sodium gluconate and tartaric acid in water and stir until uniform to obtain a mixture.

[0075] (2) The volcanic rock matrix was immersed in the mixed solution at an equal volume for 2 hours at a temperature of 25°C. After immersion, the volcanic rock matrix was removed, hung to dry to remove excess solution, and then placed in an oven to dry at 90°C for 24 hours. The dried volcanic rock matrix was then placed in a muffle furnace for oxygen-free calcination under vacuum conditions, with the temperature increased to 900°C at a rate of 10°C / min and maintained for 4 hours to obtain volcanic rock graphene adsorbent material A4. The specific parameters are shown in Table 1.

[0076] Example 5

[0077] (1) Weigh allyl alcohol, potassium gluconate, tartaric acid and water in a mass ratio of 3:5:7:100, then dissolve allyl alcohol, potassium gluconate and tartaric acid in water and stir evenly to obtain the first mixture.

[0078] (2) The volcanic rock matrix was immersed in the mixed solution at an equal volume for 2 hours at a temperature of 25°C. After immersion, the volcanic rock matrix was removed, hung to dry to remove excess solution, and then placed in an oven to dry at 90°C for 24 hours. The dried volcanic rock matrix was then placed in a muffle furnace for oxygen-free calcination under vacuum conditions, with the temperature increased to 1000°C at a rate of 10°C / min and maintained for 4 hours to obtain volcanic rock graphene adsorbent material A5. The specific parameters are shown in Table 1.

[0079] Comparative Example 1

[0080] The method described in Example 1 was followed, except that allyl alcohol was not added to the mixture to obtain adsorbent material D1, the specific parameters of which are shown in Table 1.

[0081] Comparative Example 2

[0082] The method described in Example 1 was followed, except that sodium gluconate was not added to the mixture to obtain adsorbent material D2, and the specific parameters are shown in Table 1.

[0083] Comparative Example 3

[0084] The method described in Example 1 was followed, except that tartaric acid was not added to the mixture to obtain adsorbent material D3, and the specific parameters are shown in Table 1.

[0085] Comparative Example 4

[0086] The method described in Example 1 was followed, except that the volcanic rock was replaced with porous ceramic to obtain electrode D4, the specific parameters of which are shown in Table 1.

[0087] Table 1

[0088]

[0089] Test Example 1

[0090] An aqueous solution of Luhua edible oil with an oil content of approximately 150 mg / L was used as simulated oily wastewater. An adsorption device was used to treat the simulated wastewater. The reaction tank of the adsorption device contained adsorbent material. In a simulated treatment system with a tank temperature of 25℃, a stirring speed of 500 rpm, an initial influent pH of 12±0.5, and a total reaction time of 150 min, adsorption experiments were conducted on the simulated wastewater using the aforementioned adsorbent materials A1-A5 and D1-D4. Ordinary volcanic rock was used as a control group. The adsorption performance of the adsorbent material provided by this invention is illustrated. The volume of simulated wastewater in the simulated treatment system was 3 L. Samples were taken every 30 min to determine the oil content in the system (by gravimetric method). The oil content in the simulated wastewater after 150 min of adsorption is shown in Table 2 below. Figure 2-3 The graph shows the change in oil content over time in the adsorption system, where... Figure 2 The adsorbent materials used are A1-A5. Figure 3 The adsorbents used were D1-D4 and volcanic rock.

[0091] The gravimetric method is implemented as follows: Aluminum sulfate, a coagulant, is added to the water sample, causing the oil particles dispersed in the water to agglomerate with the initially formed aluminum hydroxide. As the aluminum hydroxide precipitates, trace amounts of oil in the water are collected in the precipitate. Acidification dissolves the precipitate, and extraction with an organic solvent transfers the separated oil into the solvent. The organic solvent is then evaporated to dryness, leaving the oil in the water. The oil content in the water can then be determined by weighing.

[0092] Table 2

[0093]

[0094] As can be seen from the results in Table 2, the volcanic rock graphene adsorbent material of the present invention has a better wastewater treatment effect when treating oily wastewater.

[0095] Test Example 2

[0096] Following the method described in Test Example 1, adsorbent material A1 underwent 10 consecutive simulated wastewater treatment experiments. The simulated wastewater contained 158 mg / L of oil, and each treatment lasted 150 minutes. After each treatment, adsorbent material A1 was dried (120℃, 48 h) before the next experiment. Samples were taken every 30 minutes to measure the oil content, and the total oil removal rate for each experiment was calculated. The results are detailed in [link to test example]. Figure 4 .

[0097] pass Figure 4 It can be seen that the total oil removal rate varied little in the 10 tests, which indicates that the adsorption material provided by the present invention has high stability, can be regenerated and reused multiple times, and greatly improves the service life of the adsorption material.

[0098] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing a volcanic stone graphene adsorption material, characterized in that, Includes the following steps: (1) Glucose and / or its derivatives, polyols, organic acids and solvents are mixed to obtain a mixture; (2) The volcanic rock matrix is ​​impregnated in the mixture, and then the resulting solid material is dried and calcined in an oxygen-free environment; The weight ratio of glucose and / or its derivatives, polyols, organic acids, and solvents is 2-10:2-10:1-10:100; The amount of the mixture and the volcanic rock matrix used is such that, based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.12-0.5% by weight and the volcanic rock matrix content is 99.5-99.88% by weight.

2. The method according to claim 1, wherein, The weight ratio of glucose and / or its derivatives, polyols, organic acids, and solvents is 3-5:3-5:5-8:100; And / or, the concentration of glucose and / or its derivatives is 2-10 wt%; And / or, the concentration of polyols is 2-10 wt%; And / or, the concentration of organic acids is 1-10 wt%.

3. The method according to claim 2, wherein, The weight ratio of glucose and / or its derivatives, polyols, organic acids, and solvents is 3-5:3-5:5-8:100; And / or, the concentration of glucose and / or its derivatives is 3-5 wt%; And / or, the concentration of polyols is 3-5 wt%; And / or, the concentration of organic acids is 5-8 wt%.

4. The method according to claim 1, wherein, The glucose derivative is sodium gluconate and / or potassium gluconate.

5. The method according to claim 4, wherein, The glucose derivative is sodium gluconate.

6. The method according to claim 1, wherein, The polyol is a C2-C5 alcohol.

7. The method according to claim 6, wherein, The polyol is at least one of propylene alcohol, ethylene glycol, glycerol, and isopropanol.

8. The method according to claim 1, wherein, The organic acid is tartaric acid and / or malic acid.

9. The method according to claim 8, wherein, The organic acid is tartaric acid.

10. The method according to claim 1, wherein, The solvent is water and / or an organic solvent.

11. The method according to claim 10, wherein, The solvent is water.

12. The method according to any one of claims 1-11, wherein, The amount of the mixture and the volcanic rock matrix used is such that, based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.15-0.5% by weight and the volcanic rock matrix content is 99.5-99.85% by weight.

13. The method according to any one of claims 1-11, wherein, The conditions for impregnation in step (2) include: a temperature of 20-40℃ and a time of 2-10h.

14. The method according to any one of claims 1-11, wherein, The impregnation method is either equal-volume impregnation or excessive impregnation.

15. The method according to claim 14, wherein, The impregnation method is equal volume impregnation.

16. The method according to any one of claims 1-11, wherein, The drying conditions in step (2) include a temperature of 80-120℃ and a time of 12-24h.

17. The method according to any one of claims 1-11, wherein, The conditions for anaerobic calcination in step (2) include: calcination temperature of 800-1200℃ and calcination time of 2-6h.

18. The method according to any one of claims 1-11, wherein, The heating rate of the anaerobic roasting is 5-20℃ / min.

19. The method of claim 18, wherein, The heating rate of the anaerobic roasting is 5-10℃ / min.

20. A volcanic rock graphene adsorbent material prepared by the method according to any one of claims 1-19, characterized in that, The volcanic rock graphene adsorbent material comprises a volcanic rock matrix and carbon, with some of the carbon existing in the form of graphene. Based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.12-0.5% by weight, and the volcanic rock matrix content is 99.5-99.88% by weight. The average pore size of the volcanic rock graphene adsorbent material is 0.3-1.7 mm.

21. The adsorbent material according to claim 20, wherein, Based on the total weight of the volcanic rock graphene adsorbent material, the carbon content is 0.15-0.5% by weight, and the volcanic rock matrix content is 99.5-99.85% by weight.

22. The adsorbent material according to claim 20, wherein, The average pore size of the volcanic rock graphene adsorbent material is 0.3-1.5 mm.

23. The adsorbent material according to claim 20, wherein, The porosity of the volcanic rock graphene adsorbent material is 30-70%.

24. The adsorbent material according to claim 23, wherein, The porosity of the volcanic rock graphene adsorbent material is 30-60%.

25. The application of the volcanic rock graphene adsorbent material according to any one of claims 20-24 in the treatment of oily wastewater.

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