A method and system for rapid separation and extraction of different carbon-containing components in aerosol

Abstract

The invention discloses a method and system for rapid separation and extraction of different carbonaceous components in aerosol. The separation and extraction method is to first extract water-soluble organic carbon using dilute acid, place weighed PM2.5 filter paper samples in multiple reaction bottles, add 25% dilute phosphoric acid, remove carbonates on the PM2.5 filter paper, then insert it into a sleeve electric furnace and heat it at 70 degrees for 3 hours to obtain a dilute acid solution containing water-soluble organic carbon. Then, potassium persulfate is used for oxidation and extraction of water-insoluble organic carbon at 100 degrees. The filter paper is freeze-dried and placed in a quartz reactor. Oxygen is added at 650 degrees to obtain the elemental carbon part. In this process, all oxidized CO2 is synthesized into graphite using a graphite target synthesis system. The separation and extraction system includes a gas purification synthesis system, a vacuum system and a graphite target synthesis system. The gas purification synthesis system includes a heating treatment system and a purification system. The present invention is simple and easy to operate, can be used for large-scale sample preparation, and promotes aerosol PM2.5 research.

Description

Technical Field

[0001] The present invention belongs to the technical field of environmental quality detection, and in particular relates to a method and system for rapidly separating and extracting different carbon-containing components in an aerosol. Background Art

[0002] The content of organic carbon (OC) and elemental carbon (EC) in aerosols is relatively high, accounting for about 10% to 50% of the aerosol mass concentration, and the smaller the particle size of atmospheric particulate matter, the greater the proportion of OC and EC. OC usually refers to a variety of organic compounds such as aliphatic and aromatic compounds, including primary organic carbon (Pimary OC, POC) directly emitted by emission sources and secondary organic carbon (Secondary OC, SOC) formed through photochemical reactions and other pathways. EC refers to the part of carbon that exists in a single substance state in atmospheric particulate matter, and is a product of direct emissions from incomplete combustion of biomass or fossil fuels. In addition to OC and EC, the carbon-containing components in aerosols also include carbonates (CC), but in PM2.5 in normal weather, there is a high concentration of OC and EC. 10 、PM 2.5 The CC content in aerosol is very small, not exceeding 5%, so it is generally not considered in the analysis of carbonaceous components in aerosols.

[0003] Aerosol PM2.5 is extremely harmful to the human body. Analyzing the sources of different carbon-containing components of PM 2.5 in haze is of great significance to the control of haze.

[0004] In the existing technology, the extraction and separation of PM2.5 carbon in aerosols has always adopted the method of separating OC and EC at different temperatures. This method is cumbersome to operate and can only separate and extract one filter paper sample at a time, which is inefficient. In addition, the extraction instrument is expensive, which increases the analysis cost and greatly limits the development of extraction, separation and analysis of PM2.5 carbon in aerosols. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and system for rapid separation and extraction of different carbon-containing components in aerosol. 14 The characteristics of the C value are used in the analysis and tracing research of different carbon sources, realizing the rapid extraction of water-soluble, water-insoluble and EC components in aerosol PM2.5, and improving the efficiency of extraction and analysis.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for rapidly separating and extracting different carbon-containing components in aerosol, the steps of which include:

[0007] Step 1: Extraction of water-soluble organic carbon: Place the weighed PM2.5 filter paper samples into multiple reaction bottles, add 25% dilute phosphoric acid to remove carbonates on the PM2.5 filter paper, and then insert it into a jacketed furnace and heat at 70 degrees for 3 hours to obtain a dilute acid solution containing water-soluble organic carbon;

[0008] Step 2: Oxidation of organic carbon. The dilute acid solution containing water-soluble organic carbon in step 1 is transferred to multiple reaction bottles 2 in sequence. At this time, the water-insoluble organic carbon and elemental carbon remain on the filter paper. 6 mL of potassium persulfate solution is added to reaction bottle 1 and reaction bottle 2 respectively, and then inserted into a sleeve furnace. The bottle caps are covered, and the top pins are inserted into the bottle caps of multiple reaction bottles 1 and reaction bottle 2 respectively. Vacuuming is carried out using a vacuum system. When the vacuum degree meets the requirement, helium is injected into reaction bottle 1 and reaction bottle 2. When the pressure is greater than 1 atmosphere, the helium injection is stopped, the sleeve furnace is opened, the temperature is adjusted to 100 degrees, and the reaction is carried out for 1 hour. The first gas control valve of reaction bottle 1 and reaction bottle 2 is opened, and the CO2 gas generated by oxidation is collected and then impurities and water are removed by a purification system. Graphite is synthesized using a graphite target synthesis system until there is no CO2 in the reaction bottle.

[0009] Step 3: Elemental carbon oxidation. Take out all reaction bottles 2 from the jacket furnace, place the reaction bottles in a freeze dryer, freeze-dry the filter paper in them, place the reaction bottles in the jacket furnace, and then adjust the pressure regulator. Inject oxygen into different reaction bottles 1 in turn through pressure control, adjust the temperature of the jacket furnace to 650 degrees, react for 20 minutes, oxidize the elemental carbon on the residual filter paper, collect the CO2 gas generated by oxidation in reaction bottle 1 in turn, remove impurities and water through a purification system, and then freeze the CO2 with liquid nitrogen and use the graphite target synthesis system to synthesize graphite until there is no CO2 in the reaction bottle.

[0010] Furthermore, the vacuum degree in the above step 2 requires a pressure greater than 10 -2torr .

[0011] Furthermore, the purity of the above helium and oxygen is 99.999%.

[0012] Another aspect of the present invention provides a system for rapidly separating and extracting different carbon-containing components in an aerosol, comprising a gas purification and synthesis system, a vacuum system, and a graphite target synthesis system. The gas purification and synthesis system comprises a heating treatment system and a purification system.

[0013] The heating treatment system includes a jacketed furnace, a first reaction bottle, a second reaction bottle, a bottle cap, a main pipe, a helium gas circuit, and an oxygen gas circuit. The bottle cap is mounted on the first reaction bottle and the second reaction bottle. One end of the main pipe is connected to a thimble, which is inserted into the bottle cap. The main pipe is also provided with a pressure regulator. The helium gas circuit and the oxygen gas circuit are connected to a first branch pipe. The other end of the main pipe is connected to the purification system and the first branch pipe through a tee pipe. A second branch pipe is provided at the air inlet of the purification system. The second branch pipe is connected to the tee pipe. The second branch pipe is provided with a first gas control valve.

[0014] The purification system includes a dehydration system and an impurity removal system, the dehydration system is connected to the tee through a second branch pipe, the impurity removal system is connected to the air outlet of the dehydration system, and a pressure gauge is provided at the outlet of the impurity removal system;

[0015] The vacuum system includes a vacuum pump, a vacuum pipe and a vacuum valve, wherein the vacuum pump is connected to the air outlet of the dewatering system through the vacuum pipe, and the vacuum valve is arranged on the vacuum pipe;

[0016] The graphite target synthesis system includes a plurality of graphite target synthesis units, and the graphite target synthesis system is respectively connected to a vacuum pumping system and a gas purification synthesis system.

[0017] Furthermore, the helium gas circuit includes a helium cylinder, a helium branch pipe and a third gas control valve. The third gas control valve is arranged on the helium branch pipe. One end of the helium branch pipe is connected to the helium cylinder, and the other end is connected to the first branch pipe.

[0018] Furthermore, the oxygen gas circuit includes an oxygen cylinder, an oxygen branch pipe and a second gas control valve, wherein the second gas control valve is arranged on the oxygen branch pipe, one end of the oxygen branch pipe is connected to the oxygen cylinder, and the other end is connected to the first branch pipe.

[0019] Furthermore, the first reaction bottle is made of quartz material, and the second reaction bottle is made of ordinary glass material.

[0020] Furthermore, a gasket is provided on the inner surface of the bottle cap, and the gasket is a polytetrafluoroethylene gasket.

[0021] Furthermore, a plurality of insertion holes are provided on the top surface of the sleeve furnace, and the reaction bottle 1 and the reaction bottle 2 are respectively inserted into different insertion holes.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention uses dilute acid to extract water-soluble organic carbon, then uses potassium persulfate to oxidize it, and after the water-soluble extraction, potassium persulfate is added to oxidize the water-insoluble part, and then the residue is dried, and oxygen is added at 650 degrees to obtain the elemental carbon part, thereby realizing the rapid extraction and separation of PM2.5 carbon in aerosols. The method is simple and easy to operate, and can perform extraction and separation operations on multiple samples at the same time, and can be used for large-scale sample preparation, thereby promoting the development of aerosol PM2.5 research. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic structural diagram of a system for rapidly separating and extracting different carbon-containing components in aerosol according to the present invention;

[0024] Figure 2 This is a structural front view of the sleeve furnace of the present invention;

[0025] Figure 3 A top view of the structure of the tube furnace of the present invention;

[0026] Figure 4 This is a schematic diagram of the reaction bottle cap structure of the present invention;

[0027] Among them, 1. Tube furnace, 2. Reaction bottle 1, 3. Bottle cap, 4. Ejector pin, 5. Pressure regulator, 6. Main pipe, 7. Tee pipe, 8. First gas control valve, 9. Oxygen cylinder, 10. Second gas control valve, 11. Third gas control valve, 12. Helium cylinder, 13. Dehydration system, 14. Impurity removal system, 15. Pressure gauge, 16. Graphite target synthesis system, 17. Vacuum pump, 18. Vacuum pipe, 19. Vacuum valve, 20. Jack, 21. Gasket. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0029] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0030] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0031] Example: A method for rapidly separating and extracting different carbon-containing components in an aerosol, comprising the following steps:

[0032] Step 1: Extraction of water-soluble organic carbon: weighed PM2.5 filter paper samples were placed in multiple quartz reaction bottles 1-2, 25% dilute phosphoric acid was added to remove carbonates on the PM2.5 filter paper, and then inserted into a jacketed furnace 1 (an electric furnace) and heated at 70 degrees for 3 hours to obtain a dilute acid solution containing water-soluble organic carbon;

[0033] Step 2: Oxidation of organic carbon. The dilute acid solution containing water-soluble organic carbon in step 1 is transferred to multiple ordinary glass reaction bottles 2 in sequence. At this time, the water-insoluble organic carbon and elemental carbon remain on the filter paper. 6 mL of potassium persulfate solution is added to reaction bottle 1 2 and reaction bottle 2 respectively, and then inserted into the sleeve furnace 1. The bottle cap 3 is covered. The ejector pin 4 is inserted into the bottle caps of multiple reaction bottles 1 2 and reaction bottle 2 respectively. Vacuum is evacuated using the vacuum system. When the vacuum pressure is greater than 10 -2torr When the reaction flask 1 is heated to 100°C, the reaction is continued for 1 hour. The first gas control valves 8 of the reaction flask 1 and the reaction flask 2 are opened to collect the CO2 gas generated by oxidation, and then the impurities and water are removed by the purification system. Graphite is then synthesized by the graphite target synthesis system 16 until there is no CO2 in the reaction flask 1 and the reaction flask 2.

[0034] Step 3: Elemental carbon oxidation. Take all reaction bottles 2 out of the jacket furnace 1, place the reaction bottles in a freeze dryer, freeze-dry the filter paper therein, place the reaction bottles in the jacket furnace, and then adjust the pressure regulator, then adjust the pressure regulator 5, and inject 99.999% pure oxygen into different reaction bottles 1-2 in turn through pressure control, adjust the temperature of the jacket furnace 1 to 650 degrees, react for 20 minutes, oxidize the elemental carbon on the residual filter paper, collect the CO2 gas generated by oxidation in the reaction bottle 1-2 in turn, remove impurities and water through the purification system, and then freeze the CO2 with liquid nitrogen and use the graphite target synthesis system 16 to synthesize graphite until there is no CO2 in the reaction bottle 1-2.

[0035] A system for rapidly separating and extracting different carbon-containing components in an aerosol, comprising a gas purification and synthesis system, a vacuum pumping system, and a graphite target synthesis system 16, wherein the gas purification and synthesis system comprises a heating treatment system and a purification system;

[0036] The heating treatment system includes a jacketed furnace 1, a reaction bottle 1 2, a reaction bottle 2, a bottle cap 3, a main pipe 6, a helium gas circuit and an oxygen gas circuit. The bottle cap 3 is sleeved on the reaction bottle 1 2 and the reaction bottle 2. A polytetrafluoroethylene gasket 21 is provided on the inner surface of the bottle cap 3. One end of the main pipe 6 is connected to a thimble 4. The thimble 4 is inserted into the bottle cap 3 and passes through the gasket 21 to communicate with the reaction bottle 1 2 or the reaction bottle 2. A pressure regulator 5 is also provided on the main pipe 6. The helium gas circuit and the oxygen gas circuit are connected to a first branch pipe. The other end of the main pipe 6 is connected to the purification system and the first branch pipe through a tee pipe 7. A second branch pipe is provided at the air inlet of the purification system. The second branch pipe is connected to the tee pipe 7. The second branch pipe is provided with a first gas control valve 8.

[0037] The purification system includes a dehydration system 13 and an impurity removal system 14. The dehydration system 13 is connected to the tee pipe 7 via a second branch pipe. The impurity removal system 14 is connected to the gas outlet of the dehydration system 13. A pressure gauge 15 is provided at the outlet of the impurity removal system 14 to monitor the CO2 flow rate. The impurity removal system 14 is a purification furnace equipped with silver wire and copper particles.

[0038] The vacuum system includes a vacuum pump 17, a vacuum pipe 18 and a vacuum valve 19. The vacuum pump 17 is connected to the air outlet of the dewatering system 13 through the vacuum pipe 18. The vacuum valve 19 is provided on the vacuum pipe 18 to monitor the vacuum condition.

[0039] The graphite target synthesis system 16 includes a plurality of graphite target synthesis units, and the graphite target synthesis system 16 is connected to a vacuum system and a gas purification synthesis system respectively.

[0040] The helium gas circuit includes a helium cylinder 12, a helium branch pipe and a third gas control valve 11. The third gas control valve 11 is arranged on the helium branch pipe. One end of the helium branch pipe is connected to the helium cylinder 12, and the other end is connected to the first branch pipe.

[0041] The oxygen gas circuit includes an oxygen cylinder 9, an oxygen branch pipe and a second gas control valve 10. The second gas control valve 10 is arranged on the oxygen branch pipe. One end of the oxygen branch pipe is connected to the oxygen cylinder 9, and the other end is connected to the first branch pipe.

[0042] like Figure 3 As shown, the top surface of the sleeve furnace 1 is provided with a plurality of insertion holes 20, and the reaction bottle 1 2 and the reaction bottle 2 are respectively inserted into different insertion holes 20, so as to facilitate the fixed heating of the reaction bottle 1 2 and the reaction bottle 2.

[0043] The present invention uses dilute acid to extract water-soluble organic carbon, and then uses potassium persulfate to oxidize it. After water extraction, potassium persulfate is added to oxidize the water-insoluble part, and then freeze-dried. Oxygen is added at 650 degrees to obtain the elemental carbon part, and the organic carbon and elemental carbon are quickly separated and extracted. The graphite target synthesis system 16 is used to synthesize graphite. Different carbon-containing components have different 14 The characteristics of C values are used for different carbon source analysis and tracing studies.

[0044] While embodiments of the present invention 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 these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for rapid separation and extraction of different carbon-containing components in aerosol, characterized in that: The steps include, Step 1: Extraction of water-soluble organic carbon: Place the weighed PM2.5 filter paper samples into multiple reaction bottles, add 25% dilute phosphoric acid to remove carbonates on the PM2.5 filter paper, and then insert it into a jacketed furnace and heat at 70 degrees for 3 hours to obtain a dilute acid solution containing water-soluble organic carbon; Step 2: Oxidation of organic carbon. The dilute acid solution containing water-soluble organic carbon in step 1 is transferred to multiple reaction bottles 2 in sequence. At this time, the water-insoluble organic carbon and elemental carbon remain on the filter paper of reaction bottle 1. 6 mL of potassium persulfate solution is added to reaction bottle 1 and reaction bottle 2 respectively, and then inserted into a sleeve furnace. The bottle caps are covered, and the top pins are inserted into the bottle caps of multiple reaction bottles 1 and reaction bottle 2 respectively. Vacuuming is carried out using a vacuum system. When the vacuum degree meets the requirement, helium is injected into reaction bottle 1 and reaction bottle 2. When the pressure is greater than 1 atmosphere, the helium injection is stopped, the sleeve furnace is opened, the temperature is adjusted to 100 degrees, and the reaction is carried out for 1 hour. The first gas control valve of reaction bottle 1 and reaction bottle 2 is opened, and the CO2 gas generated by oxidation is collected and then impurities and water are removed by a purification system. Graphite is synthesized using a graphite target synthesis system until there is no CO2 in reaction bottle 1 and reaction bottle 2; Step 3: Elemental carbon oxidation. All reaction bottles 2 are taken out of the jacketed furnace, reaction bottle 1 is placed in a freeze dryer, and the filter paper therein is freeze-dried. Reaction bottle 1 is placed in the jacketed furnace, and then the pressure regulator is adjusted. Oxygen is injected into different reaction bottles 1 in turn through pressure control. The temperature of the jacketed furnace is adjusted to 650 degrees. The reaction is carried out for 20 minutes to oxidize the elemental carbon on the residual filter paper. The CO2 gas generated by oxidation in reaction bottle 1 is collected in turn, and impurities and water are removed through a purification system. Then, the CO2 is frozen by liquid nitrogen and graphite is synthesized using a graphite target synthesis system until there is no CO2 in reaction bottle 1.

2. The method for rapid separation and extraction of different carbon-containing components in aerosol according to claim 1, characterized in that: The vacuum degree in step 2 requires a pressure greater than 10 -2 torr.

3. The method for rapid separation and extraction of different carbon-containing components in aerosol according to claim 1, characterized in that: The purity of the above helium and oxygen is 99.999%.

4. The method for rapid separation and extraction of different carbon-containing components in aerosol according to claim 1, characterized in that: The system adopted by the method includes a gas purification synthesis system, a vacuum system and a graphite target synthesis system, wherein the gas purification synthesis system includes a heating treatment system and a purification system; The heating treatment system includes a jacketed furnace, a first reaction bottle, a second reaction bottle, a bottle cap, a main pipe, a helium gas circuit, and an oxygen gas circuit. The bottle cap is mounted on the first reaction bottle and the second reaction bottle. One end of the main pipe is connected to a thimble, which is inserted into the bottle cap. The main pipe is also provided with a pressure regulator. The helium gas circuit and the oxygen gas circuit are connected to a first branch pipe. The other end of the main pipe is connected to the purification system and the first branch pipe through a tee pipe. A second branch pipe is provided at the air inlet of the purification system. The second branch pipe is connected to the tee pipe. The second branch pipe is provided with a first gas control valve. The purification system includes a dehydration system and an impurity removal system, the dehydration system is connected to the tee through a second branch pipe, the impurity removal system is connected to the air outlet of the dehydration system, and a pressure gauge is provided at the outlet of the impurity removal system; The vacuum system includes a vacuum pump, a vacuum pipe and a vacuum valve, wherein the vacuum pump is connected to the air outlet of the dewatering system through the vacuum pipe, and the vacuum valve is arranged on the vacuum pipe; The graphite target synthesis system includes a plurality of graphite target synthesis units, and the graphite target synthesis system is respectively connected to a vacuum pumping system and a gas purification synthesis system.

5. The method for rapid separation and extraction of different carbon-containing components in aerosol according to claim 4, characterized in that: The helium gas circuit includes a helium cylinder, a helium branch pipe and a third gas control valve. The third gas control valve is arranged on the helium branch pipe. One end of the helium branch pipe is connected to the helium cylinder, and the other end is connected to the first branch pipe.

6. The method for rapid separation and extraction of different carbon-containing components in aerosol according to claim 4, characterized in that: The oxygen gas circuit includes an oxygen cylinder, an oxygen branch pipe and a second gas control valve, wherein the second gas control valve is arranged on the oxygen branch pipe, one end of the oxygen branch pipe is connected to the oxygen cylinder, and the other end is connected to the first branch pipe.

7. The method for rapid separation and extraction of different carbon-containing components in aerosol according to claim 4, characterized in that: The first reaction bottle is made of quartz, and the second reaction bottle is made of ordinary glass.

8. The method for rapid separation and extraction of different carbon-containing components in aerosol according to claim 4, characterized in that: A gasket is provided on the inner surface of the bottle cap, and the gasket is a polytetrafluoroethylene gasket.

9. The method for rapid separation and extraction of different carbon-containing components in aerosol according to claim 4, characterized in that: The top surface of the sleeve furnace is provided with a plurality of insertion holes, and the reaction bottle 1 and the reaction bottle 2 are respectively inserted into different insertion holes.

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