A kind of carbon-doped aluminum-based adsorbent and preparation method thereof

Abstract

The present application discloses a carbon-doped aluminum-based adsorbent and a preparation method thereof. 0.8 g of aluminum salt and 40-300 mL of a carbon source are fully stirred with a magnetic stirrer to obtain a pretreatment solution; the pretreatment solution is placed in a high-pressure reactor, and a hydrothermal method is used to react for 1-4 hours at 90-120 degrees Celsius to obtain an aluminum-based defluorinating agent; the aluminum-based defluorinating agent is washed and dried to obtain the carbon-doped aluminum-based adsorbent; the aluminum-based defluorinating agent of the present invention has the characteristics of high adsorption capacity, high selectivity, high acid and alkali applicability, reusability, good resistance to anion interference, low cost, etc.; it can quickly and efficiently remove fluoride ions in water, and is suitable for having a high adsorption capacity for fluorine between pH 3 and 12; the preparation method is simple, green, low-cost and environmentally friendly; the adsorption capacity of the aluminum-based defluorinating agent is greater than 600 mg / g, and can be used for removing fluoride ions from different types of water samples such as groundwater, tap water, and industrial wastewater.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment, and in particular relates to a carbon-doped aluminum-based adsorbent and a preparation method thereof. Background Art

[0002] At present, the commonly used defluorination methods in the field of water treatment include adsorption, chemical precipitation, ion exchange, electrocoagulation, electrodialysis, reverse osmosis and membrane separation. Most of these methods have the problems of high cost, complex process and difficult operation, which limit their application. Among various defluorination methods, adsorption is a more ideal and promising method than other technologies because of its convenient operation, low cost and relative environmental friendliness. Therefore, it is of great significance to invent a new, simple and efficient defluorination adsorbent.

[0003] The main defluorination adsorbent currently used is activated alumina, but this product has problems such as small specific surface area, low adsorption capacity (its adsorption capacity is generally in the range of 5-30 mg / g), only applicable to acidic range, and high cost. At present, a mesoporous alumina has emerged for defluorination. Due to its large specific surface area, the adsorption and defluorination capacity of mesoporous alumina is significantly improved, generally greater than 100 mg / g. However, its preparation process is complicated and usually requires the use of organic reagents, such as organic solvents, surfactants, organic aluminum raw materials, etc., and it still has limitations such as being environmentally unfriendly and high cost. Summary of the invention

[0004] Technical issues solved:

[0005] The present application aims at the deficiencies of the prior art and solves the technical problems that the current aluminum-based adsorbent has a small specific surface area, low adsorption capacity (its adsorption capacity is generally in the range of 5-30 mg / g), is only applicable to the acidic range, and has a high cost. A carbon-doped aluminum-based adsorbent and a preparation method thereof are provided. The defluorination agent adopts a carbon doping process, uses acetic acid as a carbon source, and is simply prepared by a hydrothermal method at 90-120 degrees Celsius. The preparation process is simple, green and environmentally friendly, and low in cost.

[0006] Technical solution:

[0007] To achieve the above objectives, this application is implemented through the following technical solutions:

[0008] A carbon-doped aluminum-based adsorbent, the chemical formula of the carbon-doped aluminum-based adsorbent is: AlO X C y H Z ·2H2O, where x is 3-5, y is 3.3-5, and z is 5-7.

[0009] The present application also discloses a method for preparing a carbon-doped aluminum-based adsorbent, which specifically comprises the following steps:

[0010] Step 1: 0.8 g of aluminum salt and 40-300 mL of carbon source are stirred evenly with a magnetic stirrer to prepare a pretreatment solution;

[0011] Step 2: The pre-treated solution is placed in a high-pressure reactor and reacted by a hydrothermal method at 90-120 degrees Celsius for 1-4 hours to obtain an aluminum-based defluorinating agent;

[0012] Step 3: Wash and dry the aluminum-based defluorinating agent to obtain a carbon-doped aluminum-based adsorbent.

[0013] Furthermore, in the first step, the aluminum salt is aluminum chloride or sodium aluminate.

[0014] Furthermore, in the first step, the carbon source is acetic acid.

[0015] Furthermore, in the third step, washing is performed with deionized water.

[0016] Furthermore, in the third step, drying is performed at 60 degrees Celsius.

[0017] Furthermore, the drying time in the third step is 6 hours.

[0018] Beneficial effects:

[0019] The present application provides a carbon-doped aluminum-based adsorbent and a preparation method thereof, which has the following beneficial effects compared with the prior art:

[0020] 1. The aluminum-based defluorinating agent of the present invention has the characteristics of high adsorption capacity, high selectivity, high acid and alkali applicability, reusability, good resistance to anion interference, and low cost.

[0021] 2. It can quickly and efficiently remove fluoride ions in water, and is suitable for pH between 3 and 12 with a high adsorption capacity for fluoride.

[0022] 3. The preparation method described in the present invention is simple, green, low-cost and environmentally friendly.

[0023] 4. The adsorption capacity of the aluminum-based defluorinating agent of the present invention is greater than 600 mg / g.

[0024] 5. The initial adsorption speed is fast, and the fluorine removal rate can reach 97.09% within 10 minutes of the beginning of adsorption.

[0025] 6. Aluminum-based defluoridants have excellent resistance to anion interference and reusability, and can improve the defluoridation effect and reduce waste generation in practical applications.

[0026] 7. The present invention provides a simple, green, low-cost, and excellent aluminum-based defluorination agent and a preparation method thereof, which has practical value and promotion significance.

[0027] 8. The application field of this defluoridator is very wide. It can be used to remove fluoride ions from different types of water samples such as groundwater, tap water, industrial wastewater, etc. DETAILED DESCRIPTION

[0028] In order to further illustrate the present invention, the present invention is further described in detail below in conjunction with embodiments.

[0029] Embodiment 1:

[0030] A method for preparing a carbon-doped aluminum-based adsorbent comprises the following steps:

[0031] Step 1: Mix 0.8 g aluminum chloride or sodium aluminate with 100 mL carbon source acetic acid;

[0032] Step 2: Stir evenly to prepare a pretreatment solution;

[0033] Step 3: The pre-treated solution is placed in a high-pressure reactor and reacted by a hydrothermal method at 110 degrees Celsius for 2 hours to obtain an aluminum-based defluorinating agent;

[0034] Step 4: Wash the aluminum-based defluorinating agent with deionized water and dry it at 60 degrees Celsius for 6 hours to obtain a carbon-doped aluminum-based adsorbent.

[0035] Embodiment 2:

[0036] A method for preparing a carbon-doped aluminum-based adsorbent comprises the following steps:

[0037] Step 1: 0.8 g of aluminum chloride and 40 mL of acetic acid were stirred evenly with a magnetic stirrer to prepare a pretreatment solution;

[0038] Step 2: The pre-treated solution is placed in a high-pressure reactor and reacted by a hydrothermal method at 90 degrees Celsius for 1 hour to obtain an aluminum-based defluorinating agent;

[0039] Step 3: Wash the aluminum-based defluorinating agent with deionized water and dry it at 60 degrees Celsius for 6 hours to obtain a carbon-doped aluminum-based adsorbent.

[0040] Example 3

[0041] A method for preparing a carbon-doped aluminum-based adsorbent comprises the following steps:

[0042] Step 1: 0.8 g of sodium aluminate and 300 mL of acetic acid were fully stirred with a magnetic stirrer to prepare a pretreatment solution;

[0043] Step 2: The pre-treated solution is placed in a high-pressure reactor and reacted by a hydrothermal method at 120 degrees Celsius for 4 hours to obtain an aluminum-based defluorinating agent;

[0044] Step 3: Wash the aluminum-based defluorinating agent with deionized water and dry it at 60 degrees Celsius for 6 hours to obtain a carbon-doped aluminum-based adsorbent.

[0045] The present invention is described above by way of example. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or other equivalent replacement that can be made by those skilled in the art without inventive effort falls within the protection scope of the present invention.

Claims

1. A method for preparing a carbon-doped aluminum-based adsorbent, characterized in that: The chemical formula of the carbon-doped aluminum-based adsorbent is: AlO X C y H Z 2H2O, where x is 3-5, y is 3.3-5, and z is 5-7; The method for preparing the carbon-doped aluminum-based adsorbent specifically comprises the following steps: Step 1: 0.8 g aluminum salt and 40-300 mL carbon source are stirred evenly with a magnetic stirrer to prepare a pretreatment solution; Step 2: The pre-treated solution is placed in a high-pressure reactor and reacted by a hydrothermal method at 90-120 degrees Celsius for 1-4 hours to obtain an aluminum-based defluorinating agent; Step 3: Wash and dry the aluminum-based defluorinating agent to obtain a carbon-doped aluminum-based adsorbent; In the first step, the aluminum salt is aluminum chloride or sodium metaaluminate; In the first step, the carbon source is acetic acid.

2. The method for preparing a carbon-doped aluminum-based adsorbent according to claim 1, characterized in that: In the third step, deionized water is used for washing.

3. The method for preparing a carbon-doped aluminum-based adsorbent according to claim 1, characterized in that: The third step is drying at 60 degrees Celsius.

4. The method for preparing a carbon-doped aluminum-based adsorbent according to claim 1, characterized in that: The drying time in the third step is 6 hours.