Method for detecting various arsenic forms in environment through inductively coupled plasma mass spectrometry

Abstract

The invention discloses a method for detecting various arsenic forms in an environment through inductively coupled plasma mass spectrometry. The method comprises the following steps: collecting air in the environment, continuously pressurizing the air, and storing the air in a collecting gas tank as a gas sample for later use; introducing the collected gas sample into a reaction kettle filled with a hydrochloric acid solution, mixing, conveying to a first spiral homogeneous conveying device through a first conveying pump, and then conveying to a cyclone spraying chamber; conveying the reaction kettle filled with the sodium borohydride solution to a second spiral homogeneous conveying device through a second conveying pump, and then conveying the sodium borohydride solution to a cyclone spraying chamber; argon is introduced into the cyclone spray chamber, and the cyclone spray chamber is connected with an inductively coupled plasma mass spectrometer and connected with a third delivery pump to discharge wastewater to a wastewater tank; gaseous hydride generated by the cyclone spray chamber and argon are conveyed to an inductively coupled plasma mass spectrometer for quantitative analysis. The technical effect of the invention is that the arsenic content and existence form in the environment can be better and more accurately detected.

Description

Technical Field

[0001] This invention relates to the field of arsenic speciation detection technology, specifically a method for detecting multiple arsenic speciations in the environment using inductively coupled plasma mass spectrometry. Background Technology

[0002] Arsenic is a ubiquitous nonmetallic substance in our environment. It originates from both natural and artificial resources. Natural arsenic sources include rocks and minerals in the Earth's crust, while artificial sources include the use of organoarsenic pesticides, the combustion of fossil fuels, the use of feed additives containing organoarsenic compounds, mining, industrial wastewater treatment, and the use of arsenic-containing desiccants and preservatives. Arsenic pollution is of paramount concern due to its toxicity and carcinogenicity. Therefore, it is essential to develop better and more accurate methods for detecting the concentration and forms of arsenic in the environment. Summary of the Invention

[0003] The purpose of this invention is to provide a method for detecting multiple arsenic species in the environment by inductively coupled plasma mass spectrometry, so as to achieve the technical effects proposed in the background art.

[0004] To achieve the above objectives, the invention provides the following technical solution: a method for detecting multiple arsenic species in the environment by inductively coupled plasma mass spectrometry, specifically including the following steps: Step 1: Collect ambient air, continuously pressurize it, and store it in a gas collection tank as a gas sample for later use; Step 2: The gas sample collected in Step 1 is passed into a reaction vessel containing hydrochloric acid solution, mixed, and then transported by the first transfer pump to the first spiral homogenizing conveyor, and then to the cyclone spray chamber. Step 3: The reaction vessel containing sodium borohydride solution is transported to the second spiral homogenizing conveyor via the second transfer pump, and then to the cyclone spray chamber; Step 4: Before proceeding with Steps 2 and 3, introduce argon gas into the cyclone spray chamber and connect it to the inductively coupled plasma mass spectrometer and the third delivery pump to discharge wastewater to the wastewater tank. Step 5: The gaseous hydrides generated in the cyclone spray chamber, along with argon, are transported together to an inductively coupled plasma mass spectrometer for quantitative analysis.

[0005] Preferably, the pressurization process in step one is carried out at an atmospheric pressure ratio of 1:X, where X ≥ 2.

[0006] Preferably, the first spiral homogenizing conveyor and the second spiral homogenizing conveyor have the same structure, each including a spiral conveyor and a homogenizing cylinder, and the homogenizing box is connected to the outlet of the spiral conveyor.

[0007] Preferably, the homogenizing cylinder is sealed at both ends, with an inlet at one end and an outlet at the other end, and a plurality of homogenizing grid plates are arranged inside the homogenizing cylinder along the flow direction.

[0008] Preferably, the number of homogeneous grid plates is X ≥ 5.

[0009] Preferably, the mesh size of each homogeneous grid plate decreases sequentially along the flow direction.

[0010] Compared with existing technologies, the beneficial effects of the invention are: 1. This method for detecting multiple arsenic forms in the environment using inductively coupled plasma mass spectrometry (ICP-MS) involves gaseous hydrides, including trivalent and pentavalent arsenic, generated in a cyclone spray chamber. The ICP-MS acts as an ion source, applying a high-power, high-frequency radio frequency signal to an inductive coil to create a high-temperature plasma. Gas propulsion ensures plasma equilibrium and continuous ionization. The cyanide sample to be analyzed is pumped into an atomizer via a peristaltic pump to form an aerosol, which is then carried by a carrier gas into the central region of the plasma torch, where it undergoes evaporation, decomposition, excitation, and ionization. The high-temperature plasma ionizes most elements in the sample, creating monovalent positive ions (trivalent and pentavalent arsenic). The ions from the plasma are effectively transmitted to the mass spectrometer via the ICP-MS interface. Mass spectrometry is a mass screening and analysis instrument; by selecting ions with different mass-to-nucleus ratios (m / z), it detects the intensity of a specific ion, thereby analyzing and calculating the intensity of a particular element, achieving better detection of arsenic content and its existing forms.

[0011] 2. This method for detecting multiple arsenic forms in the environment by inductively coupled plasma mass spectrometry (ICP-MS) utilizes a combination of a first helical homogenizing conveyor and a second helical homogenizing conveyor with a cyclone spray chamber to ensure a more uniform and complete reaction, thereby improving sample homogeneity and detection accuracy. Furthermore, by using a continuous pressurization method, the sample to be tested is magnified to a certain scale, resulting in even higher measurement precision. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the system principle of the invention; Figure 2 This is a schematic diagram of the inductively coupled plasma mass spectrometry detection principle of the invention. Detailed Implementation

[0013] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] Please see Figure 1 and Figure 2 The invention provides a technical solution: a method for detecting multiple arsenic species in the environment by inductively coupled plasma mass spectrometry, specifically including the following steps: Step 1: Collect ambient air, continuously pressurize it, and store it in a gas collection tank as a gas sample for later use; Step 2: The gas sample collected in Step 1 is passed into a reaction vessel containing hydrochloric acid solution, mixed, and then transported by the first transfer pump to the first spiral homogenizing conveyor, and then to the cyclone spray chamber. Step 3: The reaction vessel containing sodium borohydride solution is transported to the second spiral homogenizing conveyor via the second transfer pump, and then to the cyclone spray chamber; Step 4: Before proceeding with Steps 2 and 3, introduce argon gas into the cyclone spray chamber and connect it to the inductively coupled plasma mass spectrometer and the third delivery pump to discharge wastewater to the wastewater tank. Step 5: The gaseous hydrides generated in the cyclone spray chamber, along with argon, are transported together to an inductively coupled plasma mass spectrometer for quantitative analysis.

[0015] In this embodiment, the pressurization process in step one is carried out according to an atmospheric pressure ratio of 1:X, where X≧2.

[0016] In this embodiment, the first spiral homogenizing conveyor and the second spiral homogenizing conveyor have the same structure, each including a spiral conveyor and a homogenizing cylinder, and the homogenizing box is connected to the outlet of the spiral conveyor.

[0017] In this embodiment, the homogenizing cylinder is sealed at both ends, with an inlet at one end and an outlet at the other end. The interior of the homogenizing cylinder is provided with a plurality of homogenizing grid plates along the flow direction.

[0018] In this embodiment, the number of homogeneous grid plates is X≧5.

[0019] In this embodiment, the mesh size of each homogeneous grid plate decreases sequentially along the flow direction.

[0020] Working Principle: This method utilizes inductively coupled plasma mass spectrometry (ICP-MS) to detect various arsenic forms in the environment. Gaseous hydrides, including trivalent and pentavalent arsenic, are generated in the cyclone spray chamber. The ICP-MS acts as an ion source, applying a high-power, high-frequency radio frequency signal to the inductive coil to create a high-temperature plasma. Gas propulsion ensures plasma equilibrium and continuous ionization. The cyanide sample to be analyzed is pumped into an atomizer via a peristaltic pump to form an aerosol, which is then carried by a carrier gas to the central region of the plasma torch, where it undergoes evaporation, decomposition, excitation, and ionization. The high-temperature plasma ionizes most elements in the sample, creating monovalent positive ions (trivalent and pentavalent arsenic). The ions from the plasma are effectively transmitted to the mass spectrometer via the ICP-MS interface. Mass spectrometry is a mass screening and analysis instrument; by selecting ions with different mass-to-nucleus ratios (m / z), it detects the intensity of a specific ion, thereby analyzing and calculating the intensity of a particular element, achieving better detection of arsenic content and its existing forms. This method for detecting multiple arsenic forms in the environment using inductively coupled plasma mass spectrometry (ICP-MS) employs a combination of a first and second helical homogenizing transport device and a cyclone spray chamber to ensure a more uniform and complete reaction, thereby improving sample homogeneity and detection accuracy. Furthermore, by using continuous pressurization, the sample to be tested is magnified to a certain scale, resulting in even higher measurement precision.

[0021] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for detecting a plurality of arsenic species in the environment by inductively coupled plasma mass spectrometry, characterized by: Specifically comprising the following steps: Step one: collect the air in the environment for continuous pressure treatment stored in the collection tank as a gas sample for standby; Step two: the gas sample collected in step one is mixed with hydrochloric acid solution in the reaction kettle and then transported to the first spiral homogenizing conveying device by the first conveying pump, and then to the cyclone spray chamber; Step three: the reaction kettle containing sodium borohydride solution is transported to the second spiral homogenizing conveying device by the second conveying pump, and then to the cyclone spray chamber; Step four: before step two and step three, the cyclone spray chamber is connected with the inductively coupled plasma mass spectrometer and the third conveying pump is connected to the waste water tank for waste water discharge; Step five: the gaseous hydride generated in the cyclone spray chamber is transported to the inductively coupled plasma mass spectrometer together with argon for quantitative analysis.

2. The method for detecting various arsenic species in the environment by inductively coupled plasma mass spectrometry according to claim 1, characterized in that: The pressurization treatment in step one is carried out according to the atmospheric pressure ratio of 1:X, wherein X≧2.

3. The method for detecting various arsenic species in the environment by inductively coupled plasma mass spectrometry according to claim 1, characterized in that: The first spiral homogenizing conveying device and the second spiral homogenizing conveying device are the same in structure, and uniformly include a spiral conveyor and a homogenizing cylinder, wherein the homogenizing cylinder is connected with the outlet of the spiral conveyor.

4. The method for detecting various arsenic species in the environment by inductively coupled plasma mass spectrometry according to claim 3, characterized in that: The homogenizing cylinder is sealed at both ends, one end is provided with an inlet, and the other end is provided with an outlet, and a plurality of homogenizing grid plates are arranged in the homogenizing cylinder along the flow direction.

5. The method for detecting various arsenic species in the environment by inductively coupled plasma mass spectrometry according to claim 3, characterized in that: The number of homogenizing grid plates X≧5.

6. A method for detecting a plurality of arsenic species in the environment by inductively coupled plasma mass spectrometry as claimed in claim 5, wherein: The mesh of each homogenizing grid plate is once decreased along the flow direction.

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