Citric acid modified activated carbon material as well as preparation method and application thereof

Abstract

The invention discloses a citric acid modified activated carbon material as well as a preparation method and application thereof. Activated carbon is washed and dried to obtain pretreated activated carbon; mixing the pretreated activated carbon with a citric acid solution, and placing the mixture in an oscillation bed at room temperature for oscillation modification; filtering to remove the solution, washing to remove impurities on the surface of the activated carbon, and drying to obtain a citric acid modified activated carbon material; through citric acid modification, the number of acidic groups in the activated carbon is increased, and the adsorption performance and the adsorption capacity of main components of peculiar smell of pets are improved; the pet peculiar smell component comprises one or more of ammonia gas, trimethylamine, hydrogen sulfide and methyl mercaptan; and the adsorption capacity at normal pressure and room temperature (10-30 DEG C) reaches 450-550mg / g.

Description

Technical Field

[0001] The invention belongs to the technical field of composite materials, and specifically relates to a modified activated carbon material and a preparation method and application thereof. Background Art

[0002] As people's quality of life improves, more and more families begin to keep pets, mostly dogs, cats and other animal pets. While pets bring fun to people, they also cause some troubles, especially the odors produced during the breeding process, such as the fishy smell of oil secreted by sweat glands and the odor of excrement, which not only emit odors but also contain a variety of harmful substances. The odorous gases produced by pets mainly include nitrides (ammonia, trimethylamine), sulfides (hydrogen sulfide, methyl mercaptan), and aliphatic compounds (indole, acrolein, skatole, methane, etc.), among which ammonia content is the largest. Therefore, as high-quality pet raising becomes a trend, pet cleaning and care products, especially pet odor deodorizing products, will also become a necessity for pet owners.

[0003] The most common pet odor deodorizing products on the market include chemical, biological enzyme and plant extract deodorants. Biological enzyme deodorants are active enzymes extracted from the fermentation broth of specific microorganisms, which can degrade odor factors such as volatile fatty acids and hydrogen sulfide, but they take a long time to decompose, and the deodorizing effect will be affected by the activity of biological enzymes; chemical and plant extract deodorant materials mainly deodorize quickly and effectively through decomposition, but the cost is relatively high.

[0004] Activated carbon is an environmentally friendly adsorption material with strong adsorption capacity. It has a well-developed internal pore structure and a large specific surface area. The adsorption performance of activated carbon depends not only on physical properties such as specific surface area and porous structure, but also on surface functional groups. Activated carbon adsorption materials are inexpensive, easy to obtain, and have a large specific surface area. They can adsorb odor substances through van der Waals forces between molecules. However, the adsorption capacity of activated carbon adsorption materials for the main components of pet odors needs to be improved, and it is necessary to further enhance its adsorption performance for pet odors through modification. At present, there is almost no market product in China for modified activated carbon materials for pet odor deodorization and adsorption treatment. Therefore, the development of new high-quality modified activated carbon pet odor deodorization products has good economic and social benefits. Summary of the invention

[0005] The purpose of the present invention is to provide a citric acid modified activated carbon material for pet odor adsorption and a preparation method thereof, by citric acid modification, the number of acidic groups in the activated carbon is increased, and the adsorption performance and adsorption capacity of the main components of pet odor are improved.

[0006] In order to achieve the above purpose, the technical solutions adopted are as follows:

[0007] A citric acid modified activated carbon material is prepared by the following method:

[0008] (1) washing and drying the activated carbon to obtain pretreated activated carbon;

[0009] (2) mixing the pretreated activated carbon with a citric acid solution and placing the mixture in a shaking bed at room temperature for shaking modification;

[0010] (3) filtering to remove the solution, washing with water to remove impurities on the surface of the activated carbon, and drying to obtain a citric acid-modified activated carbon material.

[0011] Preferably, the activated carbon in step (1) is coal-based columnar activated carbon, which has a diameter of 1 to 1.6 mm, a length of 2 to 8 mm, and a BET specific surface area of ​​1000 to 1300 m 2 / g.

[0012] Preferably, the water washing method in step (1) is shaking water washing, the shaking speed is 150-250 rpm, the temperature is 20-30° C., and the time is 1-3 h.

[0013] Preferably, in step (1), the drying temperature is 100-120° C. and the drying time is 6-12 hours.

[0014] Preferably, the concentration of the citric acid solution in step (2) is 0.1-0.5 mol / L, and the volume ratio of the mass of activated carbon to the citric acid solution is 0.2-0.3 g / mL.

[0015] Preferably, the shaking speed of the shaking modification in step (2) is 150-250 rpm, the temperature is 20-30° C., and the time is 18-24 h.

[0016] Preferably, the water washing process in step (3) comprises washing the citric acid-modified activated carbon with distilled water for 1 to 3 times.

[0017] Preferably, in step (3), the drying temperature is 100-110° C. and the drying time is 10-24 h.

[0018] The present invention also provides a method for preparing a citric acid modified activated carbon material, comprising the following steps:

[0019] (1) washing and drying the activated carbon to obtain pretreated activated carbon;

[0020] (2) mixing the pretreated activated carbon with a citric acid solution and placing the mixture in a shaking bed at room temperature for shaking modification;

[0021] (3) filtering to remove the solution, washing with water to remove impurities on the surface of the activated carbon, and drying to obtain a citric acid-modified activated carbon material; the specific process parameters of each step refer to the above scheme.

[0022] The present invention provides a method for removing pet odor, comprising the following steps:

[0023] The above-mentioned citric acid-modified activated carbon material is directly placed in the living space of pets to purify the pet odor; or the above-mentioned citric acid-modified activated carbon material is applied to the purification filter element or filter screen of the air purifier and the purification fresh air fan to purify the pet odor.

[0024] Activated carbon is selected as the adsorption material, and the citric acid solution modification method is adopted to adjust the type and quantity of activated carbon groups, enhance the interaction between activated carbon and the main components of pet odor, and achieve the purpose of efficiently removing the main components of pet odor. The pet odor components targeted include one or more of ammonia, trimethylamine, hydrogen sulfide and methyl mercaptan; it can be adsorbed at normal pressure and room temperature (10-30°C), and the adsorption capacity reaches 450-550mg / g.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The present invention utilizes the modification of citric acid to change the type and quantity of activated carbon groups, thereby improving the adsorption performance and adsorption capacity of the main components of pet odor. Citric acid is an organic weak acid, green and harmless, and will not destroy the porous structure of activated carbon and affect its adsorption performance.

[0027] (2) The present invention has the advantages of simple preparation method, convenient operation, simple instruments and equipment, mild preparation conditions, easy control, easy implementation, short production cycle, simple post-processing, good repeatability, green and environmental protection, and low cost.

[0028] (3) Activated carbon is an environmentally friendly adsorption material with strong adsorption capacity, large specific surface area, well-developed internal micropores, good adsorption performance and large adsorption capacity. The present invention uses citric acid to modify the activated carbon for the main components of pet odor to be adsorbed, adjusts the type and number of activated carbon groups, and enhances the interaction with the main components of pet odor, thereby achieving the effect of adsorption performance and efficient removal of the main components of pet odor.

[0029] (4) The present invention has good adsorption performance for the main components of pet odor at room temperature and pressure, and is a pet odor adsorption material that can be commercialized. It has new product development value for pet odor deodorization and has good economic benefits, social benefits and environmental protection value.

[0030] (5) The present invention is suitable for the efficient removal of pet odors; the material can be directly placed in the space where pets live, and can effectively solve the problem of pet odor pollution in the air; the material can also be used in the purification filter element (filter screen) of air purifiers and purification fresh air fans to purify pet odors. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 : Preparation flow chart of citric acid modified activated carbon of the present invention.

[0032] Figure 2 : Actual picture of citric acid modified activated carbon prepared in Example 1.

[0033] Figure 3 : Comparison of the saturated adsorption capacity of ammonia, the main component of pet odor, by the citric acid-modified activated carbon prepared in Example 1 and the original activated carbon. DETAILED DESCRIPTION

[0034] The following examples further illustrate the technical solution of the present invention, but are not intended to limit the scope of protection of the present invention.

[0035] The specific embodiment provides a method for preparing a citric acid modified activated carbon material. Figure 1 As shown:

[0036] (1) washing and drying the activated carbon to obtain pretreated activated carbon; and preparing a citric acid solution;

[0037] (2) mixing the pretreated activated carbon with a citric acid solution and placing the mixture in a shaking bed at room temperature for shaking modification;

[0038] (3) filtering to remove the solution, washing with water to remove impurities on the surface of the activated carbon, and drying to obtain a citric acid-modified activated carbon material.

[0039] Specifically, the activated carbon in step (1) is a coal-based columnar activated carbon having a diameter of 1 to 1.6 mm, a length of 2 to 8 mm, and a BET specific surface area of ​​1000 to 1300 m 2 / g. The washing method is shaking washing, the shaking speed is 150-250rpm, the temperature is 20-30℃, and the time is 1-3h. The drying temperature is 100-120℃, and the drying time is 6-12h.

[0040] Specifically, the concentration of the citric acid solution in step (2) is 0.1-0.5 mol / L, and the volume ratio of the activated carbon mass to the citric acid solution is 0.2-0.3 g / mL. The shaking speed of the shaking modification is 150-250 rpm, the temperature is 20-30° C., and the time is 18-24 h.

[0041] Specifically, the water washing process in step (3) includes washing the citric acid modified activated carbon with distilled water for 1 to 3 times. The drying temperature is 100 to 110° C. and the drying time is 10 to 24 hours.

[0042] Example 1

[0043] Weigh 30g of activated carbon and place it in water, wash it with water at 150rpm at 25℃ for 1h, and then dry it in a drying oven at 120℃ for 6h to obtain pretreated activated carbon; weigh 10.507g of citric acid to prepare 100mL of 0.5mol / L citric acid solution; mix the activated carbon mass and the citric acid solution volume at a concentration of 0.3g / mL; place the mixed solution in a shaking bed and oscillate at room temperature for modification, with an oscillation speed of 150rpm and a temperature of 25℃ for 24h; filter the solution after oscillation for 24h; rinse the filtered citric acid modified activated carbon with water twice, and then dry it in a drying oven at 110℃ for 24h to obtain citric acid modified activated carbon material.

[0044] Figure 2 This is a physical picture of the citric acid-modified activated carbon material for pet odor prepared in Example 1. It can be seen from the figure that the activated carbon is black columnar, has a complete structure and no impurities on the surface, and the modification process does not damage the overall structure of the activated carbon.

[0045] Figure 3 This is a comparison chart of the saturated adsorption capacity of ammonia, the main component of pet odor, by the citric acid-modified activated carbon prepared in Example 1 and the original activated carbon. It can be seen from the figure that the adsorption capacity of ammonia by the citric acid-modified activated carbon is significantly improved, from 318 mg / g of the original activated carbon to 460 mg / g, so the activated carbon modified by citric acid has increased the adsorption performance of ammonia, the main component of pet odor.

[0046] Example 2

[0047] Weigh 6g of activated carbon and place it in water, wash it with water at 200rpm at 30℃ for 1h, and then put it into a drying oven at 100℃ for 6h to obtain pretreated activated carbon; weigh 2.101g of citric acid to prepare 20mL of 0.5mol / L citric acid solution; mix the activated carbon mass and the citric acid solution volume at a concentration of 0.3g / mL; put the mixed solution into a shaking bed for room temperature shaking modification, the shaking speed is 250rpm, the temperature is 30℃, and the shaking is performed for 18h; filter the solution after shaking for 18h; rinse the filtered citric acid modified activated carbon with water once, and then put it into a drying oven at 100℃ for 10h to obtain citric acid modified activated carbon material.

[0048] The citric acid modified activated carbon material for pet odor prepared in this embodiment is black columnar, with a complete structure and no impurities on the surface, and the modification process does not damage the overall structure of the activated carbon. The activated carbon modified with citric acid has a significantly improved adsorption capacity for ammonia, from 318 mg / g of the original activated carbon to 433 mg / g, so the activated carbon modified with citric acid has increased the adsorption performance of ammonia, the main component of pet odor.

[0049] Example 3

[0050] Weigh 20g of activated carbon and place it in water, wash it with water at 250rpm at 20℃ for 3h, and then put it into a drying oven at 120℃ for 12h to obtain pretreated activated carbon; weigh 2.101g of citric acid to prepare 100mL of 0.1mol / L citric acid solution; mix the activated carbon mass and the citric acid solution volume at a concentration of 0.2g / mL; put the mixed solution into a shaking bed for room temperature shaking modification, the shaking speed is 200rpm, the temperature is 20℃, and the shaking is performed for 20h; filter the solution after shaking for 20h; rinse the filtered citric acid modified activated carbon with water 3 times, and then put it into a drying oven at 110℃ for 24h to obtain citric acid modified activated carbon material.

[0051] The citric acid modified activated carbon material for pet odor prepared in this embodiment is black columnar, with a complete structure and no impurities on the surface, and the modification process does not damage the overall structure of the activated carbon. The activated carbon modified with citric acid has a significantly improved adsorption capacity for ammonia, from 318 mg / g of the original activated carbon to 396 mg / g, so the activated carbon modified with citric acid has increased the adsorption performance of ammonia, the main component of pet odor.

[0052] Example 4

[0053] Weigh 8g of activated carbon and place it in water, wash it with water at 150rpm at 20℃ for 2h, and then dry it in a drying oven at 110℃ for 6h to obtain pretreated activated carbon; weigh 2.522g of citric acid to prepare 40mL of 0.3mol / L citric acid solution; mix the activated carbon mass and the citric acid solution volume at a concentration of 0.2g / mL; place the mixed solution in a shaking bed and oscillate at room temperature for modification, with an oscillation speed of 250rpm and a temperature of 20℃ for 18h; filter the solution after oscillation for 18h; rinse the filtered citric acid modified activated carbon once with water, and then dry it in a drying oven at 100℃ for 12h to obtain citric acid modified activated carbon material.

[0054] The citric acid modified activated carbon material for pet odor prepared in this embodiment is black columnar, with a complete structure and no impurities on the surface, and the modification process does not damage the overall structure of the activated carbon. The activated carbon modified with citric acid has a significantly improved adsorption capacity for ammonia, from 318 mg / g of the original activated carbon to 427 mg / g, so the activated carbon modified with citric acid has increased the adsorption performance of ammonia, the main component of pet odor.

Claims

1. A citric acid modified activated carbon material, characterized in that Prepared in the following way: (1) washing and drying the activated carbon to obtain pretreated activated carbon; (2) mixing the pretreated activated carbon with a citric acid solution and placing the mixture in a shaking bed at room temperature for shaking modification; (3) filtering to remove the solution, washing with water to remove impurities on the surface of the activated carbon, and drying to obtain a citric acid-modified activated carbon material.

2. The citric acid modified activated carbon material according to claim 1, characterized in that The activated carbon in step (1) is a coal-based columnar activated carbon having a diameter of 1 to 1.6 mm, a length of 2 to 8 mm, and a BET specific surface area of ​​1000 to 1300 m 2 / g.

3. The citric acid modified activated carbon material according to claim 1, characterized in that The washing method in step (1) is shaking washing, the shaking speed is 150-250 rpm, the temperature is 20-30° C., and the time is 1-3 h.

4. The citric acid modified activated carbon material according to claim 1, characterized in that In step (1), the drying temperature is 100-120° C. and the drying time is 6-12 hours.

5. The citric acid modified activated carbon material according to claim 1, characterized in that The concentration of the citric acid solution in step (2) is 0.1-0.5 mol / L, and the volume ratio of the activated carbon mass to the citric acid solution is 0.2-0.3 g / mL.

6. The citric acid modified activated carbon material according to claim 1, characterized in that The shaking speed of the shaking modification in step (2) is 150-250 rpm, the temperature is 20-30° C., and the time is 18-24 h.

7. The citric acid modified activated carbon material according to claim 1, characterized in that The water washing process in step (3) includes washing the citric acid modified activated carbon with distilled water for 1 to 3 times.

8. The citric acid modified activated carbon material according to claim 1, characterized in that In step (3), the drying temperature is 100-110° C. and the drying time is 10-24 hours.

9. The method for preparing the citric acid modified activated carbon material according to claim 1, characterized in that The following steps are involved: (1) washing and drying the activated carbon to obtain pretreated activated carbon; (2) mixing the pretreated activated carbon with a citric acid solution and placing the mixture in a shaking bed at room temperature for shaking modification; (3) filtering to remove the solution, washing with water to remove impurities on the surface of the activated carbon, and drying to obtain a citric acid-modified activated carbon material.

10. A method for removing pet odor, characterized in that The following steps are involved: The citric acid modified activated carbon material described in claim 1 is directly placed in the living space of pets to purify the pet odor; or the citric acid modified activated carbon material described in claim 1 is applied to the purification filter element or filter screen of an air purifier and a purification fresh air fan to purify the pet odor.

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