Graphene functionalized Cambridge filter for trapping polycyclic aromatic hydrocarbons and preparation method thereof

Abstract

The invention relates to the field of cigarette smoke analysis, in particular to a graphene functionalized Cambridge filter for trapping polycyclic aromatic hydrocarbon and a preparation method thereof. The preparation method of the graphene functionalized Cambridge filter comprises the following steps: 1) mixing graphene oxide with a solvent to obtain a graphene oxide solution; 2) mixing the graphene oxide solution with a Cambridge filter to obtain a Cambridge filter infiltrated with graphene oxide; and 3) heating the Cambridge filter infiltrated with the graphene oxide obtained in the step 2) in the presence of a reducing agent, and washing and drying to obtain the graphene functionalized Cambridge filter. The preparation method of the functional Cambridge filter for capturing the polycyclic aromatic hydrocarbon in the main stream smoke of the cigarette is simple in technological process, convenient to manufacture and low in cost, auxiliary equipment does not need to be added, and the capturing efficiency of the polycyclic aromatic hydrocarbon in the main stream smoke of the cigarette can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of analysis of chemical components in cigarette smoke, and in particular to a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons and a preparation method thereof. Background Art

[0002] Mainstream smoke contains many carcinogenic chemical components, among which PAHs are considered to be the most carcinogenic compounds. Most of them are produced by incomplete combustion of tobacco. To date, more than 5,000 compounds have been identified in mainstream smoke. Traditional analysis methods have difficulties with PAHs with very low content. Therefore, effective capture of PAHs in cigarette smoke is the key to accurately analyze the content of PAHs in cigarette smoke, and is also very necessary for assessing public health risks.

[0003] The Cambridge filter is a filter made of glass fiber that can filter out particles with a diameter greater than 0.2μm. The filtration efficiency can reach 99% on average. It is used to collect the total particulate matter in the mainstream smoke of cigarettes during smoke component testing. It can also be used to collect the main harmful components in the mainstream smoke of cigarettes, such as polycyclic aromatic hydrocarbons, phenolic compounds, tobacco-specific nitrosamines, major carbonyl compounds, and the particulate part of hydrogen cyanide and ammonia. Since the concentration of polycyclic aromatic hydrocarbons in smoke is very low, it is necessary to use multiple Cambridge filters to capture the smoke and then combine them for analysis. In order to improve the capture efficiency of the Cambridge filter and achieve the capture of specific components through chemical adsorption, it is necessary to design a functional Cambridge filter.

[0004] In recent years, graphene-related materials have attracted the interest of many researchers, especially in pre-enrichment. Graphene has a large specific surface area and a non-localized π-electron system, which can cause its surface to chemically interact with molecules with conjugated structures and show a high adsorption capacity. The existing method uses Cambridge filters with glass fiber as the main material for capture. Its working principle is to capture polycyclic aromatic hydrocarbons in smoke aerosols through physical action. The capture effect of polycyclic aromatic hydrocarbons in cigarette smoke is not complete and cannot meet people's expectations. In addition, due to the complex composition of smoke, the Cambridge filter captures the smoke and then uses solvents to extract the matrix effect. It is necessary to remove impurities through multiple elutions through solid phase extraction columns. The operation process is complicated, consumes a lot of organic solvents, and the matrix interference is serious. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a Cambridge filter for capturing polycyclic aromatic hydrocarbons and a preparation method thereof. The present invention embeds graphene material into the Cambridge filter, fully combines the performance of the two materials, and uses the Cambridge filter to capture polycyclic aromatic hydrocarbons in cigarette smoke through functional modification, thereby achieving the maximum capture of polycyclic aromatic hydrocarbon compounds in cigarette smoke.

[0006] The purpose of the present invention can be achieved by the following technical measures:

[0007] In a first aspect, the present invention provides a method for preparing a graphene-functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons, comprising:

[0008] 1) mixing graphene oxide with a solvent to obtain a graphene oxide solution;

[0009] 2) mixing the graphene oxide solution with a Cambridge filter to obtain a Cambridge filter infiltrated with graphene oxide;

[0010] 3) The graphene oxide-impregnated Cambridge filter obtained in step 2) is subjected to a heat treatment in the presence of a reducing agent, and then washed and dried to obtain a graphene-functionalized Cambridge filter.

[0011] The present invention prepares a solution of a certain concentration of graphene oxide material, immerses the Cambridge filter disc in the graphene oxide solution, and evenly disperses the graphene oxide in the pore structure formed by the glass fiber of the Cambridge filter disc. The graphene oxide in the Cambridge filter disc forms a network structure under the condition of the presence of a reducing agent. The obtained graphene functionalized Cambridge filter disc has both the pore structure composed of the Cambridge filter disc fiber and the rich network structure of graphene. The π electrons of graphene can produce a π-π conjugation effect with polycyclic aromatic hydrocarbon molecules. The graphene functionalized Cambridge filter disc captures polycyclic aromatic hydrocarbons in cigarette smoke, which is beneficial to the separation of polycyclic aromatic hydrocarbons in the gas phase and the particle phase, and improves the capture efficiency of the Cambridge filter disc for polycyclic aromatic hydrocarbons in the mainstream cigarette smoke. There are also a large number of polar functional groups (hydroxyl, carboxyl and epoxy groups) on the surface of the graphene functionalized Cambridge filter disc, which has a super strong ability to adsorb polar compounds, and can adsorb a large number of matrix interferences on its surface, so as to achieve the separation and purification of polycyclic aromatic hydrocarbons in the mainstream cigarette smoke.

[0012] Preferably, in step 1), the concentration range of the graphene oxide solution is 1 to 1.5 g / L.

[0013] Preferably, in step 1), the solvent is selected from one or more of water, ethanol and methanol, preferably water.

[0014] Further preferably, in step 1), the graphene oxide is mixed with water and dispersed by ultrasonic vibration to obtain a uniform graphene oxide solution.

[0015] More preferably, in step 1), the power of ultrasound is 180-240 W, and the time is 30-60 min.

[0016] Preferably, in step 2), the Cambridge filter is immersed in the graphene oxide solution, and / or the graphene oxide solution is transferred and evenly dripped on the Cambridge filter; preferably, the Cambridge filter is immersed in the graphene oxide solution.

[0017] Preferably, in step 3), the reducing agent comprises hydrazine hydrate; preferably, the Cambridge filter obtained in step 2) is placed in an atmosphere of hydrazine hydrate and heated; and / or, washed with ethanol and water.

[0018] More preferably, in step 3), the heating temperature is 90-100° C. and the heating time is 0.5-2 h.

[0019] The present invention adopts specific processing raw materials, processes and the above-mentioned preferred conditions to obtain a novel graphene functionalized Cambridge filter with a polycyclic aromatic hydrocarbon capture effect that is significantly better than that of the existing process.

[0020] In a second aspect, the present invention provides a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons, which is prepared by the preparation method of the graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons.

[0021] In a third aspect, the present invention provides a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons obtained by the preparation method of the graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons or the application of the graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons in capturing polycyclic aromatic hydrocarbons in cigarette smoke.

[0022] The beneficial effect of the present invention is at least that: the functional Cambridge filter preparation method for capturing polycyclic aromatic hydrocarbons in mainstream cigarette smoke provided by the present invention first obtains a uniform graphene oxide solution by ultrasonically oscillating graphene oxide and water, infiltrates the Cambridge filter to obtain a Cambridge filter infiltrated with graphene oxide, and then heats it in an atmosphere of hydrazine hydrate to obtain a graphene functionalized Cambridge filter, which can greatly improve the capture efficiency of polycyclic aromatic hydrocarbons in mainstream cigarette smoke. The present invention has a simple process flow, is easy to manufacture, is low in cost, and does not require additional auxiliary equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art description are briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1Schematic diagram of the preparation process of the graphene functionalized Cambridge filter in an embodiment of the present invention;

[0025] Figure 2 The TIC diagrams obtained by analyzing polycyclic aromatic hydrocarbons in flue gas captured by the Cambridge filter in the embodiment of the present invention; (a) unmodified conventional Cambridge filter; (b) graphene functionalized Cambridge filter. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. 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.

[0027] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. Without departing from the spirit and substance of the present invention, modifications or substitutions made to the methods, steps or conditions of the present invention are within the scope of the present invention.

[0028] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. All reagents or instruments without manufacturer specified are conventional products that can be purchased through regular channels.

[0029] In the embodiment of the present invention, the Cambridge filter used has a diameter of 40-50 mm, preferably a 44 mm Cambridge filter.

[0030] Some embodiments of the present invention provide a method for preparing a functional composite Cambridge filter, such as Figure 1 As shown, the following steps are included:

[0031] Step 1), weighing a certain amount of graphene oxide and adding it to a certain volume of pure water, and dispersing it by ultrasonic vibration for 30min to 60min at a power of 180W to 240W to form a uniform graphene oxide solution, wherein the concentration range of the graphene oxide solution is 1 to 1.5g / L;

[0032] Step 2), then soaking the Cambridge filter in the above-mentioned graphene oxide solution, or using a pipette to transfer a certain volume of graphene oxide solution and evenly dripping it on the Cambridge filter;

[0033] Step 3), placing the Cambridge filter impregnated with graphene oxide obtained in step 2) in an atmosphere of hydrazine hydrate at 92-98° C. for 0.5-1 h, washing with ethanol and water, and drying to obtain a graphene-functionalized Cambridge filter.

[0034] In the following embodiments of the present invention, the power of ultrasonic oscillation is 200W to 220W.

[0035] The present invention will be further described in conjunction with the following examples:

[0036] Example 1

[0037] Weigh 50 mg of graphene oxide and add it to 50 mL of pure water, and disperse it by ultrasonic vibration to form a uniform graphene oxide solution with a concentration of 1.0 g / L; soak a Cambridge filter with a diameter of 44 mm in the above graphene oxide solution for 2 minutes; place the Cambridge filter soaked with graphene oxide in a hydrazine hydrate atmosphere and heat it at 95°C for 1 hour, wash it with ethanol and water, and freeze-dry it to obtain a graphene-functionalized Cambridge filter.

[0038] Example 2

[0039] 60 mg of graphene oxide was weighed and added into 50 mL of pure water, and dispersed by ultrasonic vibration to form a uniform graphene oxide solution with a concentration of 1.2 g / L; a Cambridge filter with a diameter of 44 mm was immersed in the above graphene oxide solution for 2 minutes; the Cambridge filter soaked with graphene oxide was placed in a hydrazine hydrate atmosphere and heated at 95°C for 1 hour, washed with ethanol and water, and freeze-dried to obtain a graphene-functionalized Cambridge filter.

[0040] Example 3

[0041] 75 mg of graphene oxide was weighed and added to 50 mL of pure water, and dispersed by ultrasonic vibration to form a uniform graphene oxide solution with a concentration of 1.5 g / L; a Cambridge filter with a diameter of 44 mm was immersed in the above graphene oxide solution for 10 minutes; the Cambridge filter soaked with graphene oxide was placed in a hydrazine hydrate atmosphere and heated at 95°C for 1 hour, washed with ethanol and water, and freeze-dried to obtain a graphene-functionalized Cambridge filter.

[0042] The graphene functionalized Cambridge filter obtained in the example was applied to the capture of polycyclic aromatic hydrocarbons in cigarette smoke. According to GB / T 19609, 20 cigarettes were smoked and the total particulate matter was captured with the graphene functionalized Cambridge filter. The filter was placed in an extraction bottle, 40 mL 320 μL internal standard solution was added, and ultrasonication was performed for 20 minutes. 10 mL of the extract was transferred to the solid phase extraction column, rinsed with 30 mL cyclohexane, all the eluent was collected, transferred to a round-bottom flask, and rotary evaporated at 70 ° C and 10 kPa using a rotary evaporator. The solution was concentrated to about 0.5 mL for GC-MS analysis. The TIC diagram obtained using the graphene functionalized Cambridge filter reduced many interfering chromatographic peaks ( Figure 2). Compared with the non-functionalized Cambridge filter, the quantitative determination result of the present invention is higher, and the types of PAHs analyzed are more (see Table 1), indicating that the graphene functionalized Cambridge filter prepared by the method of the present invention can capture PAHs in mainstream cigarette smoke more fully.

[0043] Table 1 Comparison of analytical methods Concentration of PAHs in 1R5F standard cigarettes (ng / cig)

[0044]

[0045]

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a graphene-functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons, characterized in that: include: 1) mixing graphene oxide with a solvent to obtain a graphene oxide solution; 2) mixing the graphene oxide solution with a Cambridge filter to obtain a Cambridge filter infiltrated with graphene oxide; 3) The graphene oxide-impregnated Cambridge filter obtained in step 2) is subjected to a heat treatment in the presence of a reducing agent, and then washed and dried to obtain a graphene-functionalized Cambridge filter.

2. The method for preparing a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to claim 1, characterized in that: In step 1), the concentration range of the graphene oxide solution is 1 to 1.5 g / L.

3. The method for preparing a graphene-functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to claim 1, characterized in that: In step 1), the solvent is selected from one or more of water, ethanol and methanol, preferably water.

4. The method for preparing a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to any one of claims 1 to 3, characterized in that: In step 1), graphene oxide is mixed with water and dispersed by ultrasonic vibration to obtain a uniform graphene oxide solution.

5. The method for preparing a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to claim 4, characterized in that: In step 1), the power of ultrasound is 180-240W, and the time is 30-60min.

6. The method for preparing a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to any one of claims 1 to 5, characterized in that: In step 2), the Cambridge filter is immersed in the graphene oxide solution, and / or the graphene oxide solution is transferred and evenly dripped onto the Cambridge filter.

7. The method for preparing a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to any one of claims 1 to 6, characterized in that: In step 3), the reducing agent comprises hydrazine hydrate; preferably, the Cambridge filter obtained in step 2) is placed in an atmosphere of hydrazine hydrate and heated; and / or, washed with ethanol and water.

8. The method for preparing a graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to claim 7, characterized in that: In step 3), the heating temperature is 90-100° C. and the heating time is 0.5-2 h.

9. A graphene-functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons, characterized in that: The filter is prepared by the method for preparing a graphene-functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons as described in any one of claims 1 to 8.

10. Use of the graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons obtained by the preparation method of the graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to any one of claims 1 to 8 or the graphene functionalized Cambridge filter for capturing polycyclic aromatic hydrocarbons according to claim 9 in capturing polycyclic aromatic hydrocarbons in cigarette smoke.

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