Preparation method of cyclobalanopsis glauca branch and leaf adsorbent for removing PM2.5

Abstract

The invention discloses a preparation method of a cyclobalanopsis glauca branch and leaf adsorbent for removing PM2.5. The preparation method comprises the following steps: collecting waste cyclobalanopsis glauca branches and leaves, cleaning, drying, cooking in boiling water, fishing out, soaking with oxalic acid and ethyl acetate to complete modification, washing the modified cyclobalanopsis glauca branches and leaves to be neutral, drying in a drying oven, and finally crushing and sieving with a 40-60-mesh sieve to obtain the adsorbent. A single factor test finds that the modified cyclobalanopsis glauca branches and leaves adsorb PM2.5, the particle size of residues of the cyclobalanopsis glauca branches and leaves is 40-60 meshes, the addition amount is 5g, the temperature is 29 DEG C, the initial concentration is 500 mu g / m < 3 >, the time is 110 minutes, and the adsorption conditions are optimal. Adsorption of the cyclobalanopsis glauca branch and leaf adsorbent on PM2.5 is a spontaneous adsorption reaction which is characterized by uneven surface and molecular layer site adsorption and takes chemical adsorption as a main component and physical adsorption as an auxiliary component. Micromorphology of branches and leaves of modified cyclobalanopsis glauca is obviously changed, a wrinkled, loose and porous structure, groups such as hydroxyl and the like are beneficial to adsorption. The PM2.5 adsorption effect of the modified cyclobalanopsis glauca branches and leaves is remarkably superior to that of other materials, and the modified cyclobalanopsis glauca branches and leaves still have a certain adsorption effect on PM2.5 after desorption circulation.

Description

Technical Field

[0001] The present invention belongs to the technical field of adsorbents, and specifically relates to a method for removing PM 2.5 A method for preparing a Cyclobalanopsis glauca branch and leaf adsorbent. Background Art

[0002] Cyclobalanopsis glauca Oerst., scientific name is Cyclobalanopsis glauca Oerst., a tree with alternate simple leaves, leathery, obovate or oblong, 6cm-14cm long, usually grows on hillsides and valleys below 2600m above sea level in my country, is shade-tolerant, prefers warm and rainy climate, calcareous soil and acidic soil, is common in limestone mountains, and mature trees can be up to 20m tall, with tall bodies and majestic postures, and can be used as garden shade trees, landscape trees and afforestation trees. Linzhi area in southeastern Tibet is rich in forest resources, with a forest area of ​​2.46 million hectares and a forest coverage rate of 46.09%. In the past 1980s, the annual logging volume in the area reached 450,000 m 3 Due to the backward production technology of the forest farm, the amount of forest waste is astonishing. According to statistics, the forest waste that has not been effectively treated in the area for a long time accounts for about 40% of the total logging volume. The total amount of forest waste is no less than 360,000 m3 per year. 3 .

[0003] PM 2.5 Particulate matter (PM) is also called fine particles or fine particles; it refers to particles with an aerodynamic equivalent diameter of less than or equal to 2.5 μm in the ambient air. It can be suspended in the air for a long time. The higher the concentration in the air, the more serious the air pollution. Compared with coarser atmospheric particulate matter, PM 2.5 Small particle size, large specific area, and stronger penetration, can reach the bronchiolar wall and interfere with gas exchange in the lungs. Moreover, they are prone to carry toxic and harmful substances (such as heavy metals, microorganisms, etc.), have a long residence time in the atmosphere, and are transported over long distances, thus having a greater impact on human health and atmospheric environmental quality.

[0004] The research on the adsorption performance of Cyclobalanopsis glauca leaves at home and abroad has achieved certain results, but there are still some shortcomings. For example, the mechanism and kinetic process of the adsorption of different pollutants by Cyclobalanopsis glauca leaves still need to be further studied; at the same time, the performance and stability of Cyclobalanopsis glauca leaves in practical applications also need to be further evaluated. In the future, as environmental pollution problems become increasingly serious, the research and application prospects of Cyclobalanopsis glauca leaves as a natural and renewable adsorbent will be broader. We can expect more in-depth research on the adsorption performance of Cyclobalanopsis glauca leaves, as well as its practical application in the fields of environmental remediation and pollution control. Therefore, the present invention uses Cyclobalanopsis glauca fallen leaf waste as raw material to explore the preparation of a material that can efficiently purify PM 2.5The rational development and utilization of Tibetan Cyclobalanopsis glauca will provide new ideas and methods for the development of efficient and environmentally friendly air purification technologies, which will help solve the current air pollution problem. Summary of the invention

[0005] In view of the above shortcomings, the present invention provides a method for removing PM 2.5 The preparation method of the Cyclobalanopsis glauca branches and leaves adsorbent is achieved by the following technical means:

[0006] The present invention first discloses a method for removing PM 2.5 The preparation method of the Cyclobalanopsis glauca branches and leaves adsorbent comprises:

[0007] (1) Raw material pretreatment: collecting discarded Cyclobalanopsis glauca branches and leaves, washing and drying them for later use;

[0008] (2) Steaming Cyclobalanopsis glauca branches and leaves: Weigh an appropriate amount of dried Cyclobalanopsis glauca branches and leaves, place them in boiling water and steam, remove them and set aside;

[0009] (3) Modification of Cyclobalanopsis glauca branches and leaves: After steaming, soak the Cyclobalanopsis glauca branches and leaves in a 0.18 mol / L oxalic acid solution for 0.5-1 h, then remove them and soak them in a 0.05 mol / L ethyl acetate solution for 24-30 h until they are fully reacted;

[0010] (4) Drying and pulverizing: The modified Cyclobalanopsis glauca branches and leaves are fished out, rinsed with distilled water until neutral, and placed in a drying oven to dry, and finally pulverized through a 40-60 mesh sieve to obtain the product.

[0011] Furthermore, the cooking time in step (2) is 20-40 minutes.

[0012] The present invention also discloses a PM removal product prepared according to the above preparation method. 2.5 Adsorbent of Cyclobalanopsis glauca branches and leaves.

[0013] The invention also discloses a method for removing PM by the above-mentioned Cyclobalanopsis glauca branches and leaves adsorbent. 2.5 Application in.

[0014] Furthermore, the application includes:

[0015] Take 5g of 40-60 mesh Cyclobalanopsis glauca branches and leaves adsorbent and, at room temperature of 20-30°C, add 500μg / m 3 Source of pollution PM 2.5 The adsorption was carried out for 110 min.

[0016] Furthermore, the application also includes:

[0017] The adsorbed Cyclobalanopsis glauca branches and leaves adsorbent was desorbed.

[0018] Further, the desorption process comprises:

[0019] Will be used for PM 2.5 The adsorbed Cyclobalanopsis glauca branches and leaves adsorbent is exposed to the sun for several times to complete the desorption.

[0020] Furthermore, the several times is 7 times, and the exposure time is 1.5 hours.

[0021] The beneficial effects of the present invention are:

[0022] The Cyclobalanopsis glauca branches and leaves adsorption material prepared by the present invention has excellent adsorption performance and can be used to purify indoor air pollutants PM 2.5 The single factor experiment was used to investigate the effect of modified Cyclobalanopsis glauca branches and leaves on PM 2.5 Adsorbed on the residue of Cyclobalanopsis glauca branches and leaves, particle size 60 mesh, addition amount 5g, temperature 20-30℃, initial concentration 500μg / m 3 , time 110min, the adsorption condition is the best. 2.5 The adsorption effect is significantly better than other materials, and it can still absorb PM after desorption cycle. 2.5 It has a certain adsorption effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Different adsorption materials for PM 2.5 The adsorption effect was compared.

[0024] Figure 2 The scanning electron microscope observation results of different Cyclobalanopsis glauca branches and leaves, among which: A is the internal image of the original Cyclobalanopsis glauca branches and leaves, B is the internal image of the modified Cyclobalanopsis glauca branches and leaves, and C is the internal image of the Cyclobalanopsis glauca branches and leaves after adsorption;

[0025] Figure 3 is an infrared spectrum analysis diagram, where: A is the untreated original cycad leaves, B is the modified cycad leaves, and C is the internal diagram of the cycad leaves after adsorption;

[0026] Figure 4 This is a graph showing the results of the desorption experiment. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0028] Unless otherwise defined, the technical or scientific terms used herein shall have the common meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "a" do not indicate a quantity limitation, but indicate the existence of at least one.

[0029] Example 1

[0030] A PM removal 2.5 The preparation method of the Cyclobalanopsis glauca branches and leaves adsorbent comprises:

[0031] (1) Raw material pretreatment: collecting discarded Cyclobalanopsis glauca branches and leaves, washing and drying them for later use;

[0032] (2) Steaming of Cyclobalanopsis glauca branches and leaves: Weigh an appropriate amount of dried Cyclobalanopsis glauca branches and leaves, place them in boiling water and steam for 20-40 min, remove them and set aside;

[0033] (3) Modification of Cyclobalanopsis glauca branches and leaves: After steaming, soak the Cyclobalanopsis glauca branches and leaves in a 0.18 mol / L oxalic acid solution for 0.5-1 h, then remove them and soak them in a 0.05 mol / L ethyl acetate solution for 24-30 h until they are fully reacted;

[0034] (4) Drying and pulverizing: The modified Cyclobalanopsis glauca branches and leaves are fished out, rinsed with distilled water until neutral, and placed in a drying oven to dry, and finally pulverized through a 40-60 mesh sieve to obtain the product.

[0035] Example 2

[0036] A Cyclobalanopsis glauca branch and leaf adsorbent for PM removal 2.5 Applications

[0037] Take 5g of 40-60 mesh Cyclobalanopsis glauca branches and leaves adsorbent and, at 20-30℃, add 500μg / m 3 Source of pollution PM 2.5 The adsorption was carried out for 110 min.

[0038] Example 3

[0039] A PM adsorption 2.5 Desorption treatment of Cyclobalanopsis glauca branches and leaves adsorbent

[0040] Will be used for PM 2.5 The adsorbed Cyclobalanopsis glauca branches and leaves adsorbent was placed in the sun for drying and ventilation for 7 times to complete the desorption.

[0041] Test Example 1

[0042] Testing different adsorption materials for PM2.5 Comparison of adsorption effects

[0043] In the same environment, the prepared adsorption material was compared with diatomaceous earth, bamboo charcoal, activated carbon, and macroporous adsorption resin AB-8 for PM 2.5 The adsorption effects were compared.

[0044] Four adsorbent material specifications:

[0045] Diatomaceous earth: white or light grey powder, 325 mesh;

[0046] Activated carbon: black granular, 60 mesh;

[0047] Macroporous adsorption resin AB-8: milky white translucent spherical particles, 18 mesh;

[0048] Modified Cyclobalanopsis glauca branches and leaves adsorbent: powder, 60 mesh;

[0049] Original Cyclobalanopsis glauca branches and leaves adsorbent: powder, 60 mesh.

[0050] Take 2g of each adsorbent material, and the initial concentration is 500μg / m 3 ; Set the adsorption time gradient to 30min, 45min, 60min, 80min, and 100min. Each adsorption material was tested three times with different gradients, and its average removal rate was calculated and the adsorption effect was compared. The results are as follows Figure 1 shown.

[0051] according to Figure 1 The results show that the adsorption effect is ranked from the best to the worst, which is modified Cyclobalanopsis glauca branches and leaves, diatomaceous earth, activated carbon, bamboo charcoal, resin and original Cyclobalanopsis glauca branches and leaves. It can be seen that the adsorption effect of the optimized Cyclobalanopsis glauca branches and leaves is the best among the six materials within the observable research range.

[0052] Test Example 2

[0053] Characterization and observation of adsorption materials

[0054] By using FTIR Fourier infrared spectrometer (refers to the use of infrared spectroscopy to analyze the structure of the original, modified cycad branches and leaves before and after adsorption, the obtained infrared spectra are compared and analyzed, and it is inferred whether the material has effective functional groups such as hydroxyl and carboxyl groups) to make the infrared spectrum of the sample and infer its molecular structure. BET parameter analysis (specific surface area refers to the total surface area occupied by 1g of solid. Generally, the larger the specific surface area, the stronger the adsorption capacity) is used to analyze the physical structure of the modified cycad branches and leaves adsorption material; element analyzer (mainly for different forms of samples and various compounds with a very wide content range to perform separate or simultaneous quantitative determination of C, H, S, and N elements, which can be widely used in research and analysis in scientific fields such as chemistry, chemical industry, pharmaceuticals, agriculture, environmental protection, and energy) and scanning electron microscope (scanning electron microscope (SEM) technology is used to observe the surface and morphological characteristics of the original cycad branches and leaves, modified cycad branches and leaves, and modified cycad branches and leaves after adsorption, and the observation results of the materials are further compared) and other equipment to characterize and analyze the prepared modified cycad branches and leaves adsorption material, and further analyze PM 2.5 Adsorption mechanism The adsorption mechanism was explored.

[0055] Characterization analysis

[0056] The results of scanning electron microscopy observations of different Cyclobalanopsis glauca branches and leaves, such as Figure 2 As shown. Among them: Figure 2 A is the internal view of the original Cyclobalanopsis glauca branches and leaves. Figure 2 B is the internal picture of the modified Cyclobalanopsis glauca branches and leaves. Figure 2 C is the internal image of the Cyclobalanopsis glauca branches and leaves after adsorption. It can be seen that the original Cyclobalanopsis glauca branches and leaves 2A still retain a large number of dense fiber mesh structures after modification, and present a loose and porous form, which greatly enhances its adsorption capacity for pollutants; while 2C can be seen that the fiber mesh structure is somewhat weakened after adsorbing pollutants. By comparing the Cyclobalanopsis glauca branches and leaves 2A and 2B, it is known that they have the same structure, that is, the fiber mesh structure on their surface gives them strong adsorption performance.

[0057] Infrared spectroscopy

[0058] like Figure 3 As shown in the figure, A is the untreated original leaves of Cyclobalanopsis glauca, B is the modified leaves of Cyclobalanopsis glauca, and C is the internal image of the leaves of Cyclobalanopsis glauca after adsorption. Infrared spectrum shows that there are many groups in the leaves of Cyclobalanopsis glauca, among which the hydroxyl group increases significantly after the optimal modification, with the largest peak; 3500cm -1 The hydroxyl group shifted significantly, proving that the leaves and branches of Cyclobalanopsis glauca adsorbed PM 2.5 Afterwards, the hydroxyl groups change and play a great role in adsorption.

[0059] Test Example 3

[0060] The element analysis was performed on the adsorbent prepared by the present invention, the unmodified Cyclobalanopsis glauca branches and leaves, and the Cyclobalanopsis glauca branches and leaves after adsorption. The specific results are shown in Table 1:

[0061] Table 1 Elemental analysis

[0062]

[0063] According to Table 1, after the raw materials were optimized, the data provided by the elemental analyzer showed that the number of groups such as C=N changed significantly.

[0064] Specific surface area and pore size analysis

[0065] Table 2 Specific surface area and pore size analysis of Cyclobalanopsis glauca branches and leaves

[0066]

[0067]

[0068] It can be concluded from Table 2 that the modified Cyclobalanopsis glauca branches and leaves are porous materials with large specific surface area, strong activity and strong adsorption capacity.

[0069] Test Example 4

[0070] Desorption and recycling

[0071] Desorption is the reverse process of adsorption, in which the adsorbent material removes PM 2.5 Finally, the material is desorbed through sun drying, which is the most common method in daily life. This process can maximize the utilization rate of the modified Cyclobalanopsis glauca branches and leaves material.

[0072] Experimental process: Weigh 2g of optimal residue and 3 The adsorption test was carried out in a closed box to calculate the removal rate. The adsorbed residue was then placed in the sun for 1.5 hours for desorption. The desorption was repeated 7 times to further understand the changes in adsorption capacity during the desorption process. The desorption test results are shown in Figure 4 Shown by: Figure 4 It can be seen that as the number of desorption times increases, the removal rate of the modified Cyclobalanopsis glauca branches and leaves material decreases, but the decline is small. The removal rate at the 7th desorption is 7.41%, which still has a good adsorption effect. This fully demonstrates that the modified Cyclobalanopsis glauca branches and leaves adsorption material can be used for PM 2.5 The results of variance analysis (F=377.53, P<0.01) fully show that the modified Cyclobalanopsis glauca branches and leaves material can be reused to adsorb PM. 2.5 .

[0073] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0074] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This description method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A method for removing PM 2.5 The preparation method of the Cyclobalanopsis glauca branches and leaves adsorbent comprises: (1) Raw material pretreatment: collecting discarded Cyclobalanopsis glauca branches and leaves, washing and drying them for later use; (2) Steaming Cyclobalanopsis glauca branches and leaves: Weigh an appropriate amount of dried Cyclobalanopsis glauca branches and leaves, place them in boiling water and steam, remove them and set aside; (3) Modification of Cyclobalanopsis glauca branches and leaves: After steaming, soak the Cyclobalanopsis glauca branches and leaves in a 0.18 mol / L oxalic acid solution for 0.5 h-1 h, then remove them and soak them in a 0.05 mol / L ethyl acetate solution for 24-30 h until they are fully reacted; (4) Drying and pulverizing: The modified Cyclobalanopsis glauca branches and leaves are fished out, rinsed with distilled water until neutral, and placed in a drying oven to dry, and finally pulverized through a 40-60 mesh sieve to obtain the product.

2. The preparation method according to claim 1, wherein: The cooking time in step (2) is 20-40 minutes.

3. A PM removal product obtained by the preparation method according to claim 1 or 2 2.5 Adsorbent of Cyclobalanopsis glauca branches and leaves.

4. A cycad glauca branch and leaf adsorbent according to claim 3 for removing PM 2.5 Application in.

5. The application according to claim 4, comprising: Take 5g of 40-60 mesh Cyclobalanopsis glauca branches and leaves adsorbent and, at room temperature of 20-30°C, add 500μg / m 3 Source of pollution PM 2.5 The adsorption was carried out for 110 min.

6. The application according to claim 4, further comprising: The adsorbed Cyclobalanopsis glauca branches and leaves adsorbent was desorbed.

7. The use according to claim 6, comprising: The desorption process comprises: Will be used for PM 2.5 The adsorbed Cyclobalanopsis glauca branches and leaves adsorbent is exposed to the sun for several times to complete the desorption.

8. The use according to claim 7, comprising: The said number of times is 7 times; The exposure time is 1-2h.

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