A kind of spherical activated carbon with wrinkled surface and its preparation method and application

Abstract

The invention discloses a spherical activated carbon with a wrinkled surface and a preparation method and application thereof, which belongs to the field of formaldehyde removal, and the method comprises the following steps: washing and drying pomegranate peel, grinding the pomegranate peel, crushing and screening through an 80-mesh screen; adding water to the pomegranate peel powder, and then heating it at 40°C; then adding 10mL of calcium chloride solution and stirring, washing and drying; taking the dried powder and dispersing it in 50mL of ethanol, ultrasonically dispersing it uniformly, adding it to a reactor and putting it in an oven for heating; cooling the reactor to room temperature, washing the powder and drying it; taking the powder and adding it to a K2CO3 solution, stirring at room temperature, and drying it; subjecting the dried solid to a two-stage heat treatment to obtain a spherical activated carbon with wrinkled surface. The spherical activated carbon with wrinkled surface described in the present invention is a spherical material, has a large specific surface area, and can improve adsorption performance; at the same time, a wrinkled structure is formed on the surface of the spherical activated carbon, which increases adsorption sites and can effectively remove formaldehyde.

Description

Technical Field

[0001] The invention belongs to the field of formaldehyde removal and relates to spherical activated carbon with wrinkled surface and a preparation method and application thereof. Background Art

[0002] Formaldehyde is a common and serious indoor pollutant, which mainly comes from decoration materials, furniture and certain daily necessities.

[0003] The adsorption method can quickly reduce the formaldehyde concentration through physical or chemical adsorption. The nature of the adsorbent determines the adsorption effect, and increasing the specific surface area of ​​the adsorbent helps to improve the adsorption performance. As a common adsorbent, activated carbon has the advantages of being cheap and stable, and is therefore widely used in the field of pollution control. However, the adsorption effect of activated carbon is limited by its morphology and structure, and its adsorption performance is average. Therefore, improving the microscopic results of activated carbon and obtaining materials with better adsorption effects will have a wider range of applications. Summary of the invention

[0004] In order to overcome the defects of the above-mentioned prior art, the present invention selects pomegranate peel as the material for preparing activated carbon, adds calcium chloride, and chelates with polyphenols such as tannins in pomegranate peel powder, and then adds K2CO3 to form calcium carbonate in situ. After high-temperature calcination, a wrinkled structure is formed. The advantages of the present invention are: (1) the spherical material has a large specific surface area and can significantly improve the adsorption performance; (2) the wrinkled structure is formed on the surface of the spherical activated carbon, which increases the adsorption sites.

[0005] The present invention provides a spherical activated carbon with a wrinkled surface. The spherical activated carbon with a wrinkled surface is a spherical structure with a large number of layered wrinkles distributed on the surface. The wrinkles on the surface increase the specific surface area, which is conducive to the contact and adsorption of the activated carbon with gas molecules.

[0006] The present invention also provides a method for preparing spherical activated carbon with wrinkled surface, the method comprising the following steps:

[0007] (1) Wash and dry the pomegranate peel, grind it into powder, and sieve it through an 80-mesh sieve.

[0008] (2) Adding water to the pomegranate peel powder screened in step (1), and then heating at 40° C.

[0009] (3) Then add 10 mL of calcium chloride solution and stir, wash and dry.

[0010] (4) Disperse the dried powder in 50 mL of ethanol, disperse it evenly by ultrasonication, add it into a reactor and heat it in an oven.

[0011] (5) Cool the reactor to room temperature, wash the powder and dry it.

[0012] (6) Take the powder dried in step (5) and add K 2 CO 3 The solution was stirred at room temperature and dried.

[0013] (7) The solid dried in step (6) is subjected to a two-stage heat treatment to obtain spherical activated carbon with a wrinkled surface.

[0014] In step (2), the ratio of the mass g of the pomegranate peel powder to the volume mL of water is 1:20-1:50.

[0015] In step (2), the heating time is 6-12 hours.

[0016] In step (3), the mass ratio of calcium chloride to pomegranate peel powder is 1:1.

[0017] In step (3), the stirring time is 10 minutes.

[0018] In step (3), the washing is performed by rinsing with distilled water three times.

[0019] In step (3), the drying temperature is 373 K.

[0020] In step (4), the mass of the powder is 1-5 g.

[0021] In step (4), the reactor is a reactor lined with Teflon.

[0022] In step (4), the heating temperature is 190°C.

[0023] In step (4), the heating time is 5-10 hours.

[0024] In step (5), the powder is washed with distilled water and acetone.

[0025] In step (5), the drying temperature is 60°C.

[0026] In step (6), the K 2 CO 3 The concentration is 200-500mg / mL.

[0027] In step (6), the mass g of the powder is related to K 2 CO 3 The volume mL ratio of the solution is 1:20.

[0028] In step (6), the stirring time is 2 hours.

[0029] In step (6), the drying temperature is 100°C.

[0030] In step (7), the two-stage heat treatment steps are: 600°C (heating rate 10°C / min) for 3 hours, and then 800°C (heating rate 5°C / min) for 2 hours.

[0031] Step (7) is preferably carried out in nitrogen.

[0032] In one embodiment, the method of the present invention comprises the following steps:

[0033] (1) Wash and dry the pomegranate peel, grind it into powder, and sieve it through an 80-mesh sieve.

[0034] (2) Take pomegranate peel powder, add appropriate amount of water, and heat at 40℃ for a certain period of time.

[0035] (3) Quickly add 10 mL of calcium chloride solution, stir for 10 min, rinse with distilled water three times, and dry at 373 K.

[0036] (4) Disperse the dried powder in 50 mL of ethanol and disperse it evenly by ultrasonication. Add the powder to a reactor lined with Teflon and place it in an oven at 190 °C for 5-10 h.

[0037] (5) The autoclave was cooled to room temperature, and the powder was washed with distilled water and acetone and dried at 60°C.

[0038] (6) Take 1g of powder and add 20mL of K 2 CO 3 The solution was stirred at room temperature for 2 h and dried at 100 °C.

[0039] (7) The collected solid was subjected to a two-stage heat treatment in nitrogen, i.e., 600°C (heating rate 10°C / min) for 3 h and then 800°C (heating rate 5°C / min) for 2 h. It was then cooled naturally to room temperature.

[0040] The present invention also provides spherical activated carbon with wrinkled surface prepared by the method.

[0041] The invention also provides application of the spherical activated carbon with wrinkled surface in removing formaldehyde.

[0042] The beneficial effects of the present invention are as follows: the spherical activated carbon with wrinkled surface described in the present invention is a spherical material, has a large specific surface area, and improves the adsorption performance; a wrinkled structure is formed on the surface of the spherical activated carbon, which increases the adsorption sites. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is the SEM image of the spherical activated carbon prepared in Examples 1-3 of the present invention.

[0044] Figure 2The activated carbon N prepared in Example 1-2 of the present invention 2 Adsorption and desorption diagram.

[0045] Figure 3 The activated carbon prepared in Examples 1-4 of the present invention and the commercial activated carbon for formaldehyde removal. DETAILED DESCRIPTION

[0046] The present invention is further described in detail with reference to the following specific examples and drawings. The process, conditions, experimental methods, etc. for implementing the present invention, except for the contents specifically mentioned below, are all common knowledge and common common sense in the art and are not particularly limited by the present invention.

[0047] The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0049] Embodiment 1:

[0050] (1) Wash and dry the pomegranate peel, grind it into powder, and sieve it through an 80-mesh sieve.

[0051] (2) Take 1g of pomegranate peel powder, add 20mL of water, and heat at 40℃ for a certain period of time.

[0052] (3) Quickly add 10 mL of 0.1 g / mL calcium chloride solution, stir for 10 min, rinse with distilled water three times, and dry at 373 K.

[0053] (4) Take 1 g of the dried powder and disperse it in 50 mL of ethanol. Ultrasonic dispersion is performed evenly. The powder is added to a reactor lined with Teflon and placed in an oven at 190 °C for 5 h.

[0054] (5) The autoclave was cooled to room temperature, and the powder was washed with distilled water and acetone and dried at 60°C.

[0055] (6) Take 1g of powder and add 20mL of 200mg / mL K 2 CO 3 The solution was stirred at room temperature for 2 h and dried at 100 °C.

[0056] (7) The collected solid was subjected to a two-stage heat treatment in nitrogen, i.e., 600°C (heating rate 10°C / min) for 3 h and then 800°C (heating rate 5°C / min) for 2 h. It was naturally cooled to room temperature to obtain spherical activated carbon with wrinkled surface.

[0057] Embodiment 2:

[0058] (1) Wash and dry the pomegranate peel, grind it into powder, and sieve it through an 80-mesh sieve.

[0059] (2) Take 1g of pomegranate peel powder, add 30mL of water, and heat at 40℃ for a certain period of time.

[0060] (3) Quickly add 10 mL of 0.1 g / mL calcium chloride solution, stir for 10 min, rinse with distilled water three times, and dry at 373 K.

[0061] (4) Take 2 g of the dried powder and disperse it in 50 mL of ethanol. Ultrasonic dispersion is performed evenly. The powder is added to a reactor lined with Teflon and placed in an oven at 190 °C for 6 h.

[0062] (5) The autoclave was cooled to room temperature, and the powder was washed with distilled water and acetone and dried at 60°C.

[0063] (6) Take 1g of powder and add 20mL of 300mg / mL K 2 CO 3 The solution was stirred at room temperature for 2 h and dried at 100 °C.

[0064] (7) The collected solid was subjected to a two-stage heat treatment in nitrogen, i.e., 600°C (heating rate 10°C / min) for 3 h and then 800°C (heating rate 5°C / min) for 2 h. It was naturally cooled to room temperature to obtain spherical activated carbon with wrinkled surface.

[0065] Embodiment 3:

[0066] (1) Wash and dry the pomegranate peel, grind it into powder, and sieve it through an 80-mesh sieve.

[0067] (2) Take 1g of pomegranate peel powder, add 50mL of water, and heat at 40℃ for a certain period of time.

[0068] (3) Quickly add 10 mL of 0.1 g / mL calcium chloride solution, stir for 10 min, rinse with distilled water three times, and dry at 373 K.

[0069] (4) Take 5 g of the dried powder and disperse it in 50 mL of ethanol. Ultrasonic dispersion is performed evenly. The powder is added to a reactor lined with Teflon and placed in an oven at 190 °C for 10 h.

[0070] (5) The autoclave was cooled to room temperature, and the powder was washed with distilled water and acetone and dried at 60°C.

[0071] (6) Take 1g of powder and add 20mL of 400mg / mL K 2 CO 3 The solution was stirred at room temperature for 2 h and dried at 100 °C.

[0072] (7) The collected solid was subjected to a two-stage heat treatment in nitrogen, i.e., 600°C (heating rate 10°C / min) for 3 h and then 800°C (heating rate 5°C / min) for 2 h. It was naturally cooled to room temperature to obtain spherical activated carbon with wrinkled surface.

[0073] Embodiment 4:

[0074] (1) Wash and dry the pomegranate peel, grind it into powder, and sieve it through an 80-mesh sieve.

[0075] (2) Take 1g of pomegranate peel powder, add 50mL of water, and heat at 40℃ for a certain period of time.

[0076] (3) Quickly add 10 mL of 0.1 g / mL calcium chloride solution, stir for 10 min, rinse with distilled water three times, and dry at 373 K.

[0077] (4) Take 5 g of the dried powder and disperse it in 50 mL of ethanol. Ultrasonic dispersion is performed evenly. The powder is added to a reactor lined with Teflon and placed in an oven at 190 °C for 10 h.

[0078] (5) The autoclave was cooled to room temperature, and the powder was washed with distilled water and acetone and dried at 60°C.

[0079] (6) Take 1g of powder and add 20mL of 500mg / mL K 2 CO 3 The solution was stirred at room temperature for 2 h and dried at 100 °C.

[0080] (7) The collected solid was subjected to a two-stage heat treatment in nitrogen, i.e., 600°C (heating rate 10°C / min) for 3 h and then 800°C (heating rate 5°C / min) for 2 h. It was naturally cooled to room temperature to obtain spherical activated carbon with wrinkled surface.

[0081] SEM Characterization:

[0082] The activated carbon materials prepared in Examples 1-3 of the present invention are all spherical activated carbons with wrinkled surfaces.

[0083] Nitrogen adsorption and desorption testing

[0084] The adsorption of N at 298 K was measured by ASAP 2460. 2 The adsorption-desorption isotherm of Figure 2 The persimmon fiber aerogels prepared in Examples 1-2 of the present invention all have a mesoporous structure, and the adsorption capacity reaches 91 mmol / g.

[0085] Formaldehyde removal experiment

[0086] The temperature and humidity in the 200L sealed cabin were controlled at 27℃ and 50%. The heating table was preheated to 80℃ in the cabin. 150ul of formaldehyde solution was dropped into a glass culture dish and placed on the heating table for 30 minutes to completely volatilize the formaldehyde. Then 10g of activated carbon sample was added. The atmospheric sampler was used to sample at different time points and the values ​​were recorded. Figure 3 As shown, compared with the commercial activated carbon sample (i.e., Desheng coconut shell activated carbon, produced by Liyang Desheng Activated Carbon Factory), the activated carbon prepared in Examples 1-4 of the present invention is more efficient in removing formaldehyde, removing 99% of formaldehyde within 24 hours.

[0087] Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0088] As used in the present invention, the term "comprising" is an open expression, that is, including the contents specified in the present invention but not excluding other contents.

[0089] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0090] Although the embodiments of the present description have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present description, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing spherical activated carbon with wrinkled surface, characterized in that: The method comprises the following steps: (1) Wash and dry the pomegranate peel, grind it into powder, and sieve it through an 80-mesh sieve; (2) adding water to the pomegranate peel powder screened in step (1), and then heating at 40° C.; (3) Then add 10 mL of calcium chloride solution and stir, wash and dry; (4) Disperse the dried powder in 50 mL of ethanol, disperse it evenly by ultrasonication, add it into a reactor and heat it in an oven; (5) Cooling the reactor to room temperature, washing the powder and drying it; (6) Add the powder dried in step (5) into a K2CO3 solution, stir at room temperature, and dry; the concentration of K2CO3 is 200-500 mg / mL; the ratio of the mass g of the powder to the volume mL of the K2CO3 solution is 1:20; (7) The solid dried in step (6) is subjected to a two-stage heat treatment to obtain spherical activated carbon with a wrinkled surface; the two-stage heat treatment comprises the following steps: heating at 600°C for 3 hours at a heating rate of 10°C / min, and then heating at 800°C for 2 hours at a heating rate of 5°C / min.

2. The preparation method according to claim 1, characterized in that In step (2), the ratio of the mass g of the pomegranate peel powder to the volume mL of water is 1:20-1:50; and / or the heating time is 6-12 hours.

3. The preparation method according to claim 1, characterized in that: In step (3), the mass ratio of calcium chloride to pomegranate peel powder is 1:1; and / or the stirring time is 10 min; and / or the washing is performed by rinsing with distilled water for 3 times; and / or the drying temperature is 373 K.

4. The preparation method according to claim 1, characterized in that: In step (4), the mass of the powder is 1-5 g; and / or the heating temperature is 190° C.; and / or the heating time is 5-10 h.

5. The preparation method according to claim 1, characterized in that: In step (5), the washing is performed using distilled water and acetone to wash the powder; and / or the drying temperature is 60°C.

6. The preparation method according to claim 1, characterized in that: In step (6), the stirring time is 2 hours; and / or the drying temperature is 100°C.

7. Spherical activated carbon with wrinkled surface prepared by the preparation method according to any one of claims 1 to 6.

8. Use of the spherical activated carbon with wrinkled surface as claimed in claim 7 in removing formaldehyde.

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