An oil-water separation modified filter material and its preparation method

Abstract

This invention discloses an oil-water separation modified filter media and its preparation method. The invention utilizes polyvinyl alcohol, agarose powder, polyethylene glycol, and tannic acid to prepare a modification solution, which is then used to soak and modify the filter media, thereby obtaining an oil-water separation modified filter media. The modified filter media of this invention possesses superhydrophilic-superoleophobic properties in water, thus exhibiting excellent self-cleaning performance against oil adhesion, while the treated wastewater meets discharge standards.

Description

Technical Field

[0001] This invention specifically relates to an oil-water separation modified filter material and its preparation method. Background Technology

[0002] Treating oily wastewater is quite challenging, and the commonly used treatment methods include the following:

[0003] Gravity methods, such as air flotation equipment and oil skimmers, have the disadvantage of not being able to completely remove oil slicks. Oil droplets and oil spores on the water surface, especially water-soluble oil, cannot be removed and can only be pretreated.

[0004] Filtration methods, such as membrane separation, have the disadvantage of large equipment investment, especially the high requirements for organic matter pretreatment, otherwise the membrane will be damaged, affecting its efficiency and significantly increasing the cost of use;

[0005] Adsorption methods, such as activated carbon, have the drawback of low oil absorption capacity; generally, one ton of activated carbon can only absorb less than 20 kilograms of oil.

[0006] Biological-mechanical separation method: The disadvantage is that culturing microorganisms is relatively troublesome, the survival environment of microorganisms is demanding, and it is difficult to find ideal organisms;

[0007] Heating and steam separation methods: The drawback is high operating costs.

[0008] Other technologies, such as using fiber ball filter media, quartz sand filter media, coconut shell filter media, etc., are used for filtration, but these filter media products for treating oily wastewater have low oil absorption capacity and are difficult to make the treated wastewater meet the discharge standards. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides an oil-water separation modified filter media and its preparation method. The oil-water separation modified filter media prepared by this invention possesses superhydrophilic-superoleophobic properties in water, thereby exhibiting excellent self-cleaning performance against oil adhesion, while the treated wastewater meets discharge standards.

[0010] This invention is achieved using the following technical solution:

[0011] A method for preparing an oil-water separation modified filter media includes the following steps:

[0012] S1. Preparation of modified solution

[0013] Polyvinyl alcohol powder was placed in water and heated until dissolved to obtain a polyvinyl alcohol solution with a mass concentration of 5 g / L to 10 g / L; agarose powder was placed in water and heated until dissolved to obtain an agarose solution with a mass concentration of 1 g / L.

[0014] After cooling, the polyvinyl alcohol solution and the agarose solution are mixed and stirred evenly at a volume ratio of 1:1 to obtain a mixed solution;

[0015] Then, tannic acid and polyethylene glycol powder are added sequentially to the mixed solution and stirred evenly to obtain a modified solution; the concentration of tannic acid in the modified solution is 2 g / L, and the concentration of polyethylene glycol in the modified solution is 2 g / L.

[0016] S2, Filter media impregnation modification

[0017] First, the modified solution is diluted 2 to 3 times, and then the filter material is immersed in the diluted modified solution for 1 to 3 hours. The mass ratio of the modified solution to the filter material is 1:2. After immersion, the filter material is filtered and dried to obtain the modified filter material.

[0018] Preferably, the polyvinyl alcohol has a degree of polymerization of 2600 and a degree of alcoholysis of 99%.

[0019] Preferably, the gelation temperature of the agarose is 36°C.

[0020] Preferably, the polyethylene glycol has a molecular weight of 4000.

[0021] Preferably, the filter media is at least one of quartz sand, ceramsite, and zeolite.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] This invention utilizes a modified solution prepared from polyvinyl alcohol, agarose powder, polyethylene glycol, and tannic acid to immerse and modify filter media, thereby obtaining an oil-water separation modified filter media. The modified filter media of this invention possesses superhydrophilic-superoleophobic properties in water, thus exhibiting excellent self-cleaning performance against oil adhesion, while the treated wastewater meets discharge standards. Attached Figure Description

[0024] Figure 1 SEM image of the oil-water separation modified filter media prepared in Example 1;

[0025] Figure 2 The contact angle of crude oil on the surface of the oil-water separation modified filter media prepared in Example 1;

[0026] Figure 3 The sliding angle of hexadecane on the surface of the oil-water separation modified filter media prepared in Example 1. Detailed Implementation

[0027] The present invention will be further described below with reference to specific embodiments.

[0028] Example 1

[0029] A method for preparing an oil-water separation modified filter media is as follows:

[0030] S1. Preparation of modified solution

[0031] Polyvinyl alcohol powder was placed in water and heated until dissolved to obtain a polyvinyl alcohol solution with a mass concentration of 10 g / L; agarose powder was placed in water and heated until dissolved to obtain an agarose solution with a mass concentration of 1 g / L.

[0032] After cooling, the polyvinyl alcohol solution and the agarose solution are mixed and stirred evenly at a volume ratio of 1:1 to obtain a mixed solution;

[0033] Then, tannic acid and polyethylene glycol powder are added sequentially to the mixed solution and stirred evenly to obtain a modified solution; the concentration of tannic acid in the modified solution is 2 g / L, and the concentration of polyethylene glycol in the modified solution is 2 g / L.

[0034] S2, Filter media impregnation modification

[0035] First, the modified solution is diluted by 2 times, and then the quartz sand (average particle size of 0.8 mm) is soaked in the diluted modified solution for 2 hours. The mass ratio of the modified solution to the filter material is 1:2. After soaking, the filter is filtered and dried to obtain the modified filter material.

[0036] Example 2

[0037] A method for preparing an oil-water separation modified filter media is as follows:

[0038] S1. Preparation of modified solution

[0039] Polyvinyl alcohol powder was placed in water and heated until dissolved to obtain a polyvinyl alcohol solution with a mass concentration of 5 g / L; agarose powder was placed in water and heated until dissolved to obtain an agarose solution with a mass concentration of 1 g / L.

[0040] After cooling, the polyvinyl alcohol solution and the agarose solution are mixed and stirred evenly at a volume ratio of 1:1 to obtain a mixed solution;

[0041] Then, tannic acid and polyethylene glycol powder are added sequentially to the mixed solution and stirred evenly to obtain a modified solution; the concentration of tannic acid in the modified solution is 2 g / L, and the concentration of polyethylene glycol in the modified solution is 2 g / L.

[0042] S2, Filter media impregnation modification

[0043] First, the modified solution is diluted 3 times, and then the quartz sand (average particle size of 1.5 mm) is soaked in the diluted modified solution for 3 hours. The mass ratio of the modified solution to the filter material is 1:2. After soaking, the filter is filtered and dried to obtain the modified filter material.

[0044] Example 3

[0045] A method for preparing an oil-water separation modified filter media is as follows:

[0046] S1. Preparation of modified solution

[0047] Polyvinyl alcohol powder was placed in water and heated until dissolved to obtain a polyvinyl alcohol solution with a mass concentration of 8 g / L; agarose powder was placed in water and heated until dissolved to obtain an agarose solution with a mass concentration of 1 g / L.

[0048] After cooling, the polyvinyl alcohol solution and the agarose solution are mixed and stirred evenly at a volume ratio of 1:1 to obtain a mixed solution;

[0049] Then, tannic acid and polyethylene glycol powder are added sequentially to the mixed solution and stirred evenly to obtain a modified solution; the concentration of tannic acid in the modified solution is 2 g / L, and the concentration of polyethylene glycol in the modified solution is 2 g / L.

[0050] S2, Filter media impregnation modification

[0051] First, the modified solution is diluted 3 times, and then the quartz sand (average particle size of 3.5 mm) is soaked in the diluted modified solution for 1 hour. The mass ratio of the modified solution to the filter material is 1:2. After soaking, the filter is filtered and dried to obtain the modified filter material.

[0052] The modified filter media prepared in Example 1 was tested in water containing crude oil. Figure 2 As shown, the contact angle of crude oil on the modified filter media is 160°.

[0053] The modified filter media prepared in Example 1 was tested in water containing hexadecane. Figure 3 As shown, the sliding angle of hexadecane oil on its surface is 3°.

[0054] It should be noted that the above examples are merely some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments and other modifications are possible. All modifications directly or indirectly derived by those skilled in the art from the disclosure of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A method for preparing an oil-water separation modified filter material, characterized in that, Includes the following steps: S1. Preparation of modified solution Polyvinyl alcohol powder is placed in water and heated until dissolved to obtain a polyvinyl alcohol solution with a mass concentration of 5 g / L to 10 g / L. Agarose powder was placed in water and heated until dissolved to obtain an agarose solution with a mass concentration of 1 g / L. After cooling, the polyvinyl alcohol solution and the agarose solution are mixed and stirred evenly at a volume ratio of 1:1 to obtain a mixed solution; Then, tannic acid and polyethylene glycol powder are added sequentially to the mixed solution and stirred until homogeneous to obtain a modified solution; The concentration of tannic acid in the modified solution is 2 g / L, and the concentration of polyethylene glycol in the modified solution is 2 g / L. S2, Filter media impregnation modification First, the modified solution is diluted 2 to 3 times, and then the filter material is immersed in the diluted modified solution for 1 to 3 hours. The mass ratio of the modified solution to the filter material is 1:

2. After immersion, the filter material is filtered and dried to obtain the modified filter material.

2. The preparation method according to claim 1, characterized in that, The polyvinyl alcohol has a degree of polymerization of 2600 and a degree of alcoholysis of 99%.

3. The preparation method according to claim 1, characterized in that, The gelation temperature of the agarose is 36°C.

4. The preparation method according to claim 1, characterized in that, The molecular weight of the polyethylene glycol is 4000.

5. The preparation method according to claim 1, characterized in that, The filter media is at least one of quartz sand, ceramsite, and zeolite.

6. An oil-water separation modified filter media, characterized in that, It is prepared using any one of the methods described in claims 1 to 5.

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