A sulfur-oxygen functional group adsorption material, its preparation method and application

Abstract

The present invention provides a sulfur-oxygen functional group adsorption material, its preparation method and application, belonging to the technical field of environmental protection new energy materials. It includes the following steps: (1) placing ultrafine polypropylene fibers in concentrated sulfuric acid and heating for sulfonation treatment to obtain sulfonated fibers; (2) mixing the sulfonated fibers with an activator and performing one-step carbonization activation to obtain the sulfur-oxygen functional group adsorption material. The sulfur-oxygen functional group adsorption material obtained by the preparation method of the present invention has a specific surface area of 1865-2264 m 2 / g, has a rich microporous-mesoporous structure, can serve as a transport channel, reduces the transport resistance of guest molecules, and improves the mass transfer efficiency. The adsorption capacity for the volatile organic gas methanol is as high as 18.49 mmol / g, and the adsorption capacity for CO2 is as high as 4.54 mmol / g, showing extremely high adsorption capacity.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental protection new energy materials, and particularly relates to a sulfur-oxygen functional group adsorption material, a preparation method thereof, and an application thereof. Background Art

[0002] The influence of sulfur-doped porous carbon materials has been a hot topic reported in recent years. Researchers have discussed the influence of single sulfur-containing functional groups on improving the adsorption amounts of CO2 and VOCs, but have ignored the oxygen functional groups widely present in porous carbon materials. Therefore, it is necessary to further consider the gas adsorption performance under the synergistic effect of S / O functional groups and pore structure.

[0003] The electrostatic force on the surface of ultra-fine polypropylene fiber materials is relatively strong, and it is very difficult to remove bacteria or viruses by simple water washing, which also brings inconvenience to the recycling of disposable medical masks (DMMs). Among the existing treatment methods for waste DMMs, such as high-temperature incineration, landfill degradation, and mechanical recycling, are not ideal due to disadvantages such as secondary pollution and long time consumption. The chemical recycling method can reconstruct ultra-fine polypropylene fibers to form new materials to achieve the purpose of resource reuse, but it is restricted by the chemical stability and physical properties of ultra-fine polypropylene fibers. Summary of the Invention

[0004] The purpose of the present invention is to provide a sulfur-oxygen functional group adsorption material, a preparation method thereof, and an application thereof, so as to solve the problems of pollution and complex process in the preparation of ultra-high specific surface area porous carbon materials in the prior art.

[0005] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0006] The present invention provides a preparation method of a sulfur-oxygen functional group adsorption material, comprising the following steps:

[0007] (1) Subjecting ultra-fine polypropylene fibers to heating and sulfonation treatment in concentrated sulfuric acid to obtain sulfonated fibers;

[0008] (2) Mixing the sulfonated fibers with an activator and performing one-step carbonization and activation to obtain the sulfur-oxygen functional group adsorption material.

[0009] Preferably, the temperature of the sulfonation treatment in step (1) is 130-150 °C.

[0010] Preferably, the time of the sulfonation treatment in step (1) is 3-5 h.

[0011] Preferably, the mass ratio of the activator to the sulfonated fibers in step (2) is 1:2-6.

[0012] Preferably, the activator in step (2) is zinc chloride.

[0013] Preferably, the temperature of the carbonization activation in step (2) is 550 - 650 °C.

[0014] Preferably, the time of the carbonization activation in step (2) is 1 - 2 h.

[0015] The present invention also provides a sulfur-oxygen functional group adsorbent material obtained by the preparation method of the sulfur-oxygen functional group adsorbent material described above.

[0016] The present invention also provides the application of the sulfur-oxygen functional group adsorbent material in the adsorption and removal of volatile organic gases methanol and CO2.

[0017] The present invention has the following beneficial effects:

[0018] The present invention provides a preparation method of a sulfur-oxygen functional group adsorbent material, comprising the following steps: (1) placing ultrafine polypropylene fibers in concentrated sulfuric acid for heating and sulfonation treatment to obtain sulfonated fibers; (2) mixing the sulfonated fibers with an activator for one-step carbonization activation to obtain the sulfur-oxygen functional group adsorbent material.

[0019] The ultrafine polypropylene fibers selected in the present invention are from the ultrafine polypropylene fiber layer in waste masks. As a kind of solid waste, it solves the problem of a large amount of waste accumulation; zinc chloride is selected as the activator, which has the characteristics of high activation efficiency and can effectively etch the carbon layer, thereby generating a rich pore structure.

[0020] The sulfur-oxygen functional group adsorbent material provided by the present invention has a specific surface area of 1865 - 2264 m 2 / g and has a rich micropore-mesopore structure, which can be used as a transport channel, reducing the transport resistance of guest molecules and improving the mass transfer efficiency.

[0021] The present invention also provides the application of the sulfur-oxygen functional group adsorbent material in the adsorption and removal of volatile organic gases methanol and CO2. After testing, the adsorption capacity for volatile organic gas methanol is as high as 18.49 mmol / g, and the adsorption capacity for CO2 is as high as 4.54 mmol / g, showing extremely high adsorption ability. Description of the Drawings

[0022] Figure 1 It is a flow chart for preparing the sulfur-oxygen functional group adsorbent material in Example 1;

[0023] Figure 2 It is a pore size distribution diagram for preparing the sulfur-oxygen functional group adsorbent material in Examples 1 - 3;

[0024] Figure 3 It is a low-temperature nitrogen isothermal adsorption curve diagram for preparing the sulfur-oxygen functional group adsorbent material in Examples 1 - 3;

[0025] Figure 4CO2 isothermal adsorption curves of the sulfur-oxygen functional group adsorption materials prepared in Examples 1 to 3;

[0026] Figure 5 Isothermal methanol adsorption curve of the sulfur-oxygen functional group adsorption material obtained in Example 2. Detailed implementation manners

[0027] The present invention provides a preparation method of a sulfur-oxygen functional group adsorption material, comprising the following steps:

[0028] (1) Placing ultrafine polypropylene fibers in concentrated sulfuric acid for heating and sulfonation treatment to obtain sulfonated fibers;

[0029] (2) Mixing the sulfonated fibers with an activator and performing one-step carbonization activation to obtain the sulfur-oxygen functional group adsorption material.

[0030] In the present invention, the ultrafine polypropylene fibers used in step (1) are the ultrafine polypropylene fibers in waste masks, and the specific production process is as follows:

[0031] Disinfecting the waste masks, and then taking out the ultrafine polypropylene fibers by manual means. The disinfection is preferably ultraviolet lamp disinfection, and the time of the ultraviolet lamp disinfection is preferably 20 - 28 h, more preferably 22 - 26 h, and even more preferably 23 - 25 h.

[0032] In the present invention, the concentration of the concentrated sulfuric acid in step (1) is preferably 98%.

[0033] In the present invention, the temperature of the sulfonation treatment in step (1) is preferably 130 - 150 °C, more preferably 135 - 145 °C, and even more preferably 138 - 143 °C.

[0034] In the present invention, the time of the sulfonation treatment in step (1) is preferably 3 - 5 h, more preferably 3.5 - 4.5 h, and even more preferably 3.8 - 4.2 h.

[0035] In the present invention, by performing sulfonation treatment on the ultrafine polypropylene fibers, the infusibility of the ultrafine polypropylene fibers is improved.

[0036] In the present invention, after the sulfonation treatment in step (1) is completed, the reaction product is washed and dried in sequence to obtain the sulfonated fibers.

[0037] In the present invention, the mass ratio of the activator to the sulfonated fibers in step (2) is preferably 1:2 - 6, more preferably 1:3 - 5, and even more preferably 1:3.5 - 4.5.

[0038] In the present invention, the activator in step (2) is preferably zinc chloride.

[0039] In the present invention, the mixing time in step (2) is preferably 30 to 40 minutes, more preferably 32 to 38 minutes, and still more preferably 34 to 36 minutes.

[0040] In the present invention, the carbonization activation in step (2) is carried out under the condition of introducing an inert gas. The inert gas is preferably nitrogen, and the flow rate of the inert gas is preferably 55 - 65 m 3 / h, more preferably 57 - 63 m 3 / h, and still more preferably 59 - 61 m 3 / h.

[0041] In the present invention, the temperature of the carbonization activation in step (2) is preferably 550 - 650 °C, more preferably 560 - 640 °C, and still more preferably 580 - 620 °C.

[0042] In the present invention, the time of the carbonization activation in step (2) is preferably 1 - 2 h, more preferably 1.2 - 1.8 h, and still more preferably 1.4 - 1.6 h.

[0043] In the present invention, after the carbonization activation process in step (2) is completed, the obtained black product is immersed in dilute hydrochloric acid and stirred, then taken out, washed, filtered by suction, and dried to obtain the sulfur-oxygen functional group adsorbent material. The mass concentration of the dilute hydrochloric acid is preferably 3 - 6%, more preferably 3.5 - 5.5%, and still more preferably 4 - 5%; the stirring time is preferably 30 - 40 h, more preferably 32 - 38 h, and still more preferably 34 - 36 h; the washing method is preferably washing with distilled water until the filtrate is neutral; the drying time is preferably 20 - 28 h, more preferably 22 - 26 h, and still more preferably 23 - 25 h.

[0044] The present invention also provides the sulfur-oxygen functional group adsorbent material obtained by the preparation method of the sulfur-oxygen functional group adsorbent material described above.

[0045] The present invention also provides the application of the sulfur-oxygen functional group adsorbent material in adsorbing and removing volatile organic gases methanol and CO2.

[0046] In the present invention, unless otherwise specified, the required preparation raw materials are all commercially available products well-known to those skilled in the art.

[0047] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0048] Example 1

[0049] Irradiate the waste masks with an ultraviolet lamp for 24 h to disinfect the waste masks, and then take out the ultra-fine polypropylene fibers by manual means for standby.

[0050] The ultrafine polypropylene fiber is placed in concentrated sulfuric acid with a concentration of 98%, heated to 140°C, and kept warm for 4 hours for sulfonation treatment. After the reaction is completed, the sulfonated fiber is obtained by washing and drying.

[0051] Zinc chloride and sulfonated fiber were mixed in a mass ratio of 1:2 and ground for 30 minutes until they were ground into powder and mixed evenly. 3 Nitrogen is introduced at a flow rate of / h, and carbonization activation is performed at a temperature of 600°C for 1.5h to obtain a black product. The black product is stirred with 5% dilute hydrochloric acid for 36h, and then repeatedly washed with distilled water until the filtrate is neutral, and then filtered and dried in a vacuum drying oven for 24h to obtain the sulfoxide functional group adsorption material.

[0052] Example 1 Flow chart of preparing sulfur oxygen functional group adsorption material Figure 1 shown.

[0053] Example 2

[0054] The preparation process is basically the same as that of Example 1, the only difference being that the mass ratio of zinc chloride to sulfonated fiber is 1:4.

[0055] Example 3

[0056] The preparation process is basically the same as that of Example 1, except that the mass ratio of zinc chloride to sulfonated fiber is 1:6.

[0057] Performance Testing

[0058] After the sulfur-oxygen functional group adsorption materials obtained in Examples 1 to 3 were vacuum treated at 150° C. for 6 hours, low-temperature nitrogen isothermal adsorption was performed using a JW-BK132Z specific surface area analyzer (manufactured by Beijing Jingwei Gaobo Science and Technology Co., Ltd.) (implementing standards GB / T 21650.2, GB / T 19587, and GB / T21650.3), and the specific surface area was calculated using a multi-point BET calculation method, and the pore size distribution was calculated using an NLDFT model. The results are shown in Table 1; wherein the pore size distribution is as follows: Figure 2 As shown in the figure, the low temperature nitrogen isotherm adsorption curve is as follows Figure 3 shown.

[0059] Table 1 Pore structure parameters of the sulfur oxygen functional group adsorption materials obtained in Examples 1 to 3

[0060]

[0061] It can be seen from Table 1 that the specific surface areas of the sulfur-oxygen functional group adsorption materials prepared by the present invention are 1865, 2117 and 2264 m 2 / g.

[0062] Depend on Figure 2It can be seen that the sulfur-oxygen functional group adsorption material obtained in the present invention has the strongest peak at 1.1 nm, and the positions of the peaks in the micropores of Examples 1 to 3 are the same (0.8 nm, 1.1 nm, 1.4 nm, 1.7 nm).

[0063] The element and functional group contents of the sulfur-oxygen functional group adsorption materials obtained in Examples 1 to 3 calculated from the fitting spectra are shown in Table 2 below.

[0064] Table 2 Elemental composition of the sulfur-oxygen functional group adsorption materials obtained in Examples 1 to 3

[0065] Case C (at%) S (at%) O (at%) Example 1 92.15 0.98 6.87 Example 2 90.33 0.48 9.19 Example 3 88.04 0.77 10.59

[0066] As can be seen from Table 2, after the sulfonated fiber is carbonized and activated with zinc chloride, the obtained sulfur-oxygen functional group adsorption material mainly contains carbon, oxygen, and sulfur elements, forming an S / O co-doped surface.

[0067] Application Example

[0068] The CO2 isothermal adsorption curves of the sulfur-oxygen functional group adsorption materials obtained in Examples 1 to 3 were plotted under the conditions of an adsorption temperature of 0 °C and an adsorption pressure of 100 kPa, as Figure 4 shown.

[0069] From Figure 4 it can be seen that the order of the CO2 adsorption amounts is Example 2 > Example 3 > Example 1, and the highest adsorption amount reaches 4.54 mmol / g at 0 °C.

[0070] Selecting methanol with stronger polarity as the representative adsorbate, the adsorption of methanol by the sulfur-oxygen functional group adsorption material obtained in Example 2 was tested under the conditions of an adsorption temperature of 20 °C and an adsorption pressure of 12 kPa, as Figure 5 shown.

[0071] From Figure 5 it can be seen that the maximum adsorption amount of the sulfur-oxygen functional group adsorption material obtained in Example 2 for methanol reaches 18.49 mmol / g.

[0072] As can be seen from the above examples, the present invention provides a preparation method of a sulfur-oxygen functional group adsorption material, which comprises the following steps: (1) heating ultrafine polypropylene fibers in concentrated sulfuric acid for sulfonation treatment to obtain sulfonated fibers; (2) mixing the sulfonated fibers with an activator for one-step carbonization activation to obtain the sulfur-oxygen functional group adsorption material. The sulfur-oxygen functional group adsorption material obtained by the preparation method of the present invention has a specific surface area of 1865 - 2264 m 2 / g, with a rich microporous-mesoporous structure. After testing, the adsorption capacity for the volatile organic gas methanol is as high as 18.49 mmol / g, and the adsorption capacity for CO2 is as high as 4.54 mmol / g, showing extremely high adsorption ability.

[0073] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. Application of a sulfur-oxygen functional group adsorbent material in adsorptive removal of volatile organic gas methanol and CO2, and preparation method of the sulfur-oxygen functional group adsorbent material, characterized in that, It includes the following steps: (1) Place the ultrafine polypropylene fiber in concentrated sulfuric acid and heat it for sulfonation treatment to obtain sulfonated fiber; (2) Mix the sulfonated fiber with an activator and perform one-step carbonization activation to obtain the sulfur-oxygen functional group adsorption material; In step (1), the ultrafine polypropylene fiber comes from the ultrafine polypropylene fiber layer in waste masks. Disinfect the waste masks, and then take out the ultrafine polypropylene fiber by manual means; In step (1), the temperature of the sulfonation treatment is 130-150°C, and the time of the sulfonation treatment is 3-5h; In step (2), the activator is zinc chloride; In step (2), the mass ratio of the activator to the sulfonated fiber is 1:2-6; In step (2), the temperature of the carbonization activation is 550-650°C, and the time of the carbonization activation is 1-2h.

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