Application of basic aluminum acetate in water treatment defluorination

Abstract

The application discloses application of basic aluminum acetate in fluorine removal in water treatment and relates to a new use of the basic aluminum acetate, which is used for fluorine removal in water and wastewater treatment and has a good removal effect. The application solves the shortcomings of other adsorbents, such as complex preparation process, low adsorption capacity, involvement of organic aluminum and high-molecular template reagent, high cost, potential toxicity, slow initial adsorption speed and the like, thereby saving a large amount of time and energy consumption, not being affected by the existing product characteristics and achieving unexpected technical effects. In addition, the current widely used defluorination adsorbent active alumina has the problems of small specific surface area, low adsorption capacity, a theoretical maximum adsorption capacity usually lower than 10 mg / g, narrow application range, poor recyclability, high treatment cost and the like. The basic aluminum acetate has the advantages of small dosage, high fluorine removal rate, wide applicable pH range, large maximum adsorption capacity and a high theoretical value of 27.7 mg / g, and has significant technical progress.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of environmental protection water treatment, and particularly relates to application of basic aluminum acetate in water treatment defluorination. BACKGROUND

[0002] Fluorine is one of the trace elements necessary for human body, and is closely related to human life activities. At a lower concentration, fluoride is beneficial to tooth development and treatment of osteoporosis, but long-term use can cause fluoride poisoning, kidney damage, and even cancer. Fluoride affecting human health mainly comes from drinking water and food in nature. The fluoride content in drinking water is mainly determined by the fluorine contained in the earth's crust, and is also affected by industrial wastewater discharge. Fluoride existing in drinking water is more likely to cause serious harm to humans than fluoride exposed alone. Therefore, defluorination of drinking water is the only feasible method to solve the problem of excessive fluoride in drinking water. At present, the defluorination methods of water body mainly include adsorption method, chemical precipitation method, ion exchange method, electric coagulation method, electrodialysis method, reverse osmosis method and membrane separation method, etc. Although these methods show good defluorination effect, they have problems such as high requirement for instruments, high detection cost, and limited scope of application in actual operation. Among various defluorination methods, the adsorption method is a more ideal and promising method than other technologies due to 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 current maturely applied defluorination adsorbent is mainly active alumina, but this product has problems such as small specific surface area, low adsorption capacity (the theoretical maximum adsorption capacity is usually less than 10mg / g), only suitable for acidic range, poor recyclability, and high treatment cost. SUMMARY

[0004] Technical problems solved:

[0005] The technical problems solved by the present application can be divided into two aspects: 1) the deficiencies of traditional active alumina defluorination materials, such as low adsorption capacity and slow initial adsorption speed; and 2) overcoming the problems of new defluorination materials such as complex preparation process, high cost, potential toxic risk, and involving organic aluminum and high molecular template reagents. In view of the above technical problems, the application provides application of basic aluminum acetate in water treatment defluorination.

[0006] Technical scheme:

[0007] To achieve the above purpose, the technical scheme is as follows:

[0008] The application of basic aluminum acetate in water treatment defluorination specifically comprises the following steps:

[0009] First step: take 0.04g commercial basic aluminum acetate sample and place in a 50ml EP tube;

[0010] Second step: add 40ml, 10mg / L NaF solution to the above EP tube, mix well to prepare sample solution;

[0011] Third step: adjust the pH of the above sample solution to 3-6;

[0012] Fourth step: place the EP tube in a constant temperature shaking box and shake at room temperature for 20-24h.

[0013] Further, the preparation method of the 10mg / L NaF solution in the second step is to dissolve 2.21g NaF in 1000ml deionized water to prepare a 1g / L fluoride stock solution. The stock solution can be diluted to prepare a 10mg / L fluoride standard solution.

[0014] Further, the reagent for adjusting pH in the third step is 0.1mol / L NaOH and 0.1mol / L HNO3.

[0015] Further, the NaF is analytical grade.

[0016] Further, the concentration of fluoride ions measured after shaking for 20-24h is lower than 1.0mg / L.

[0017] The technical principle of the present application is that basic aluminum acetate is a white amorphous powder. It gradually loses the acetic acid smell and becomes alkaline when left for a long time or boiled in water. It is slightly soluble in alkali, difficult to dissolve in acid, insoluble in water, non-toxic, and prepared by the reaction of aluminum hydroxide and acetic acid. It is used as a mordant, printing agent and pharmaceutical industry, and there is no report of its use as a defluorination agent for water treatment. The principle of the above-mentioned basic aluminum acetate in the application of defluorination in water treatment is that in addition to the combination of aluminum in the reagent with fluorine, the carbonyl group of the acetic acid group can ion exchange with fluoride ions and produce C-F combination. When it is used for the removal of fluorine in water and wastewater, it has good effect, and the maximum adsorption capacity is as high as 27.7mg / g, which is significantly better than the traditional active alumina defluorination effect.

[0018] Beneficial effects:

[0019] The present application provides the application of basic aluminum acetate in defluorination in water treatment. Compared with the prior art, it has the following beneficial effects:

[0020] 1. The application relates to a new use of an existing product, basic aluminum acetate, which is used for the removal of fluorine in water and wastewater treatment, has a good removal effect, solves the problems of a complex preparation process, low adsorption capacity, the involvement of organic aluminum and high-molecular-template reagents, high cost, potential toxicity and slow initial adsorption speed of other adsorbents, thereby saving a large amount of time and energy consumption, and achieving unexpected technical effects without the enlightenment of the characteristics of the existing product.

[0021] 2. Compared with traditional aluminum oxide, the dosage is smaller, and the dosage of active aluminum oxide is 3-17 times more than that.

[0022] 3. The defluorination rate of the defluorination agent is more than 87% under the adsorption conditions of an initial fluorine ion concentration of 10 mg / L, an adsorbent dosage of 1 g / L and a pH of 5.

[0023] 4. The pH application range is wide, and the defluorination effect is significantly better than that of traditional active aluminum oxide.

[0024] 5. Under the adsorption conditions of an initial fluorine ion concentration of 10 mg / L, an adsorbent dosage of 1 g / L and a pH of 5, the defluorination rate of the defluorination agent can reach 92.11%, and the maximum adsorption capacity is as high as 27.7 mg / g, which is significantly higher than the adsorption capacity of 7 mg / g of traditional active aluminum oxide defluorination agent. DETAILED DESCRIPTION

[0025] In order to further illustrate the application, the application is further described in detail in combination with examples.

[0026] The basic aluminum acetate is purchased from a Nantong University instrument purchasing platform, the supplier is Nantong Qixiang Biotechnology Co., Ltd., the brand name is Macklin, and the specification is 100 g. The original analytical reagent is used without further purification.

[0027] Example 1

[0028] The application of a kind of basic aluminum acetate in water treatment defluorination specifically includes the following steps:

[0029] Step 1: 0.04 g of a commercial basic aluminum acetate sample is weighed and placed in a 50 ml EP tube;

[0030] Step 2: 40 mL of a 10 mg / L NaF solution is added to the EP tube, and the sample solution is prepared by mixing;

[0031] Step 3: The pH of the sample solution is adjusted to 3;

[0032] Step 4: The EP tube is placed in a constant-temperature shaking box and shaken at room temperature for 20-24 hours. Under the adsorption conditions of an initial fluorine ion concentration of 10 mg / L, an adsorbent dosage of 1 g / L and a pH of 3, the defluorination rate of the defluorination agent can reach 81.70%, and the experimental adsorption capacity is 8.69 mg / g.

[0033] Example 2

[0034] The application of basic aluminum acetate in water treatment for removing fluorine includes the following steps:

[0035] Step 1: weigh 0.04 g of commercial basic aluminum acetate sample into a 50 ml EP tube;

[0036] Step 2: add 40 mL of 10 mg / L NaF solution into the EP tube, mix well to prepare a sample solution;

[0037] Step 3: adjust the pH of the sample solution to 4;

[0038] Step 4: place the EP tube in a constant temperature shaking box and shake at room temperature for 20-24 h; under the adsorption conditions of initial fluorine ion concentration of 10 mg / L, 1 g / L adsorbent dosage, and pH of 4, the fluorine removal rate of the fluorine removal agent can reach 81.77%, and the experimental adsorption capacity is 8.70 mg / g.

[0039] Example 3

[0040] The application of basic aluminum acetate in water treatment for removing fluorine includes the following steps:

[0041] Step 1: weigh 0.04 g of commercial basic aluminum acetate sample into a 50 ml EP tube;

[0042] Step 2: add 40 mL of 10 mg / L NaF solution into the EP tube, mix well to prepare a sample solution;

[0043] Step 3: adjust the pH of the sample solution to 5;

[0044] Step 4: place the EP tube in a constant temperature shaking box and shake at room temperature for 20-24 h; under the adsorption conditions of initial fluorine ion concentration of 10 mg / L, 1 g / L adsorbent dosage, and pH of 5, the fluorine removal rate of the fluorine removal agent can reach 92.11%, and the experimental adsorption capacity is 9.80 mg / g.

[0045] Example 4

[0046] The application of basic aluminum acetate in water treatment for removing fluorine includes the following steps:

[0047] Step 1: weigh 0.04 g of commercial basic aluminum acetate sample into a 50 ml EP tube;

[0048] Step 2: add 40 mL of 10 mg / L NaF solution into the EP tube, mix well to prepare a sample solution;

[0049] Step 3: adjust the pH of the sample solution to 6;

[0050] The fourth step: placing the EP tube in a constant temperature shaking box and shaking at room temperature for 20-24 hours, the initial concentration of fluoride ions is 10 mg / L, the dosage of the adsorbent is 1 g / L, and the adsorption condition is that the pH is 6, and the fluorine removal rate of the fluorine removal agent can reach 87.73%, and the experimental adsorption capacity is 9.33 mg / g.

[0051] Comparative Example 1:

[0052] The application of active aluminum oxide in water treatment for removing fluorine, the initial concentration of fluoride ions is 5 mg / L, the dosage of the active aluminum oxide adsorbent is 3 g / L, and the adsorption condition is that the pH is 5 (the optimal pH condition), and the fluorine removal rate of the active aluminum oxide reaches 55%. The adsorption capacity is only 0.75 mg / g.

[0053] Comparative Example 2:

[0054] The application of active aluminum oxide in water treatment for removing fluorine, the initial concentration of fluoride ions is 5 mg / L, the dosage of the active aluminum oxide adsorbent is 5 g / L, and the adsorption condition is that the pH is 5 (the optimal pH condition), and the fluorine removal rate of the active aluminum oxide reaches 61%. The adsorption capacity is only 0.39 mg / g.

[0055] Comparative Example 3:

[0056] The application of active aluminum oxide in water treatment for removing fluorine, the initial concentration of fluoride ions is 5 mg / L, the dosage of the active aluminum oxide adsorbent is 7 g / L, and the adsorption condition is that the pH is 5 (the optimal pH condition), and the fluorine removal rate of the active aluminum oxide reaches 73%. The adsorption capacity is only 0.19 mg / g.

[0057] Comparative Example 4:

[0058] The application of active aluminum oxide in water treatment for removing fluorine, the initial concentration of fluoride ions is 5 mg / L, the dosage of the active aluminum oxide adsorbent is 17 g / L, and the adsorption condition is that the pH is 5 (the optimal pH condition), and the fluorine removal rate of the active aluminum oxide reaches 83%. The adsorption capacity is only 0.05 mg / g.

[0059] In summary, when the dosage of the basic aluminum acetate is 1 g / L, the fluorine removal rate is maintained above 87% under the condition that the pH is 3-6, the experimental adsorption capacity is 5.26-9.80 mg / g, which is much higher than the experimental adsorption capacity of the active aluminum oxide, which is 0.05-0.75 mg / g. The technical features of low dosage, high fluorine removal rate, wide applicable pH range, large adsorption capacity (the theoretical value is as high as 27.7 mg / g), etc. are achieved, and significant technical progress is achieved.

[0060] The above describes the application by way of example, and it should be noted that any simple modification, change or equivalent replacement that does not deviate from the core of the application and can be easily replaced by those skilled in the art without creative labor falls within the protection scope of the application.

Claims

1. Use of basic aluminum acetate in defluoridation in water treatment, characterized in that, Specifically comprising the following steps: Step 1: weigh 0.04g of commercial basic aluminum acetate sample into a 50ml EP tube; Step 2: add 40mL of 10mg / L NaF solution into the EP tube, mix well to prepare a sample solution; Step 3: adjust the pH of the sample solution to 3-6; Step 4: place the EP tube in a constant temperature shaking box and shake at room temperature for 20-24h; The preparation method of the 10mg / L NaF solution in the second step is to dissolve 2.21g of NaF in 1000mL of deionized water to prepare a 1g / L fluoride stock solution; the stock solution can be diluted to prepare a 10mg / L fluoride standard solution; The reagent for adjusting the pH in the third step is 0.1mol / L NaOH and 0.1mol / L HNO3; The NaF is analytical grade; The fluoride ion concentration is less than 1.0mg / L after shaking for 20-24h.