CN114184565A - Novel method for detecting total arsenic of heavy metal in sediment by atomic fluorescence spectrophotometer - Google Patents
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Abstract
The invention discloses a novel method for detecting total arsenic of heavy metals in sediments by an atomic fluorescence spectrophotometer, and belongs to the technical field of substance detection. The novel method for detecting the total arsenic of the heavy metal in the sediment by using the atomic fluorescence spectrophotometer comprises the following steps: s1: digestion of the sediment: drying the sediment to constant weight, and performing closed microwave digestion in a Teflon TFM digestion tank to obtain a sample; s2: extracting a sample solution by a stepwise digestion method; s3: transferring the sample solution into a test tube containing a solution to be detected by an atomic fluorescence spectrophotometer, adding 0.5g of thiourea powder, covering a plug, vibrating, standing for 30-50min, and measuring after the sample is fully reduced. The method can quickly and accurately measure the arsenic content in the sediment, has high accuracy, has small interference compared with other methods, and has small measurement error.
Description
Technical Field
The invention belongs to the technical field of material detection, and particularly relates to a novel method for detecting total arsenic of heavy metal in sediment by using an atomic fluorescence spectrophotometer.
Background
In recent years, with the rapid development of economy, the national soil pollution standard exceeding rate is 16.1%, the main pollution types are inorganic types, and the inorganic pollutants in the top three are cadmium, mercury and arsenic in sequence. Therefore, by the department of ecological environment and the State market supervision and management administration, in the 8 th month of 2018, the soil pollution risk control Standard for soil environmental quality construction land (trial) GB36600-2018 and the soil pollution risk control Standard for soil environmental quality agricultural land (trial) GB 15618-2018 are issued jointly, and specific requirements are made on the limit value of the heavy metal in the soil, so that an analysis method for accurately and quickly determining the heavy metal in the soil is urgently needed to be established.
The soil is formed and evolved under the comprehensive action of various soil forming factors such as parent material, climate, biology, terrain, time and the like, the soil is very complex in composition and generally consists of solid, liquid and gas phases such as organic matters, moisture and air generated by decay of mineral matters and animal and plant residues, and due to the serious pollution at present, arsenic in soil sediments is increased, the growth of vegetation is not facilitated, and the environment pollution is caused; the detection of traditional soil and deposit arsenic adopts artifical sample, detects at the use instrument, wastes time and energy, detects singlely, and the degree of accuracy is low, very easily because other metallics influence the testing result in the soil, are unfavorable for the user and detect.
Chinese patent document "method for measuring arsenic content in iron ore by hydride generation-atomic fluorescence spectrometry (patent number: CN 201310090843.0)" discloses a method for measuring arsenic content in iron ore, which comprises preparing sample solution of iron ore sample, and preparing standard solution of arsenic; and introducing the sample solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity of arsenic in the sample solution, and calculating the content of arsenic in the sample solution according to the fluorescence intensity measured by the arsenic standard solution with known concentration. The method has the advantages of low detection limit, high determination speed and simple and convenient operation, but has the problem that the accuracy of the arsenic content needs to be improved.
Disclosure of Invention
The invention aims to provide a novel method for detecting total arsenic of heavy metal in sediment by using an atomic fluorescence spectrophotometer, which aims to solve the problems of how to optimize the process and improve the accuracy of arsenic content determination on the basis of the disclosure of a method (patent number: CN201310090843.0) for determining the arsenic content in iron ore by hydride generation-atomic fluorescence spectrometry in Chinese patent document.
In order to solve the technical problems, the invention adopts the following technical scheme:
a novel method for detecting total arsenic of heavy metal in sediment by using an atomic fluorescence spectrophotometer comprises the following steps:
s1: digestion of the sediment: drying the sediment to constant weight, and performing closed microwave digestion in a polytetrafluoroethylene (Teflon TFM) digestion tank to obtain a sample;
s2: extracting a sample by using 1.0mol/L ammonium chloride solution to obtain a first arsenic solution; extracting the first arsenic solution by adopting 0.5mol/L ammonium fluoride solution to obtain a second arsenic solution; extracting the second arsenic solution by using 0.5mol/L sodium hydroxide solution to obtain a third arsenic solution; extracting the third arsenic solution by using a 0.5mol/L sulfuric acid solution to obtain a fourth arsenic solution, and extracting the fourth arsenic solution by using a nitric acid-sulfuric acid-perchloric acid mixed solution to obtain a sample solution;
s3: transferring the sample solution into a test tube containing a solution to be detected by an atomic fluorescence spectrophotometer, adding 0.5g of thiourea powder, covering a plug, vibrating, standing for 30-50min, and measuring after the sample is fully reduced.
Preferably, the preparation of the standard solution is also included: preparing arsenic standard solution with the following concentration in a 100mL volumetric flask by using nitric acid aqueous solution:
a.0.00ng/mL，1.00ng/mL，2.00ng/mL，4.00ng/mL,8.00ng/mL，10.00ng/mL；
b.0.00ng/mL，5.00ng/mL，10.00ng/mL，20.00ng/mL，40.00ng/mL，50ng/mL；
respectively adding a reduction masking agent, standing at room temperature for 30min, respectively introducing each arsenic standard solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity of arsenic, and drawing two working curves; and introducing each sample solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity corresponding to arsenic in the sample solution, and determining the content of the arsenic according to the working curve.
Preferably, the deposit in the step S1 is dried at 50-60 ℃, and the part with the particle size less than 65 μm is screened as the sample.
Preferably, in the step S1, the microwave digestion is to accurately weigh the sediment and put the sediment into a microwave digestion tank of teflon TFM, add 15mL of phosphoric acid solution, cover the tank, seal the tank, and put the tank in a microwave digestion system for assisted extraction.
Preferably, the microwave digestion procedure is that the temperature is increased to 90-95 ℃ from room temperature within 10min, the temperature is kept at 90-95 ℃ for 15-20min, the microwave digestion tank is opened when the temperature is reduced to below 30 ℃, the microwave digestion tank is washed by deionized water for 3 times, the microwave digestion tank and the digestion solution are poured into a centrifuge tube together, centrifugal separation is carried out, the volume of the upper layer extracting solution is determined to be 25mL, and the upper layer extracting solution is filtered by a cellulose acetate filter membrane with the aperture of 0.22 mu m.
Preferably, the rotation speed of the centrifugal separation is 5000rpm, and the separation time is 10 min.
Preferably, the reduction masking agent is thiourea powder.
The invention has the following beneficial effects:
(1) according to the microwave digestion treatment method, the sediment is subjected to microwave digestion treatment, and under the action of a microwave field, polar molecules absorbing microwaves are quickly turned and directionally arranged, so that high-speed collision and friction are generated among the molecules, high heat is generated, the surface layer of the sediment is continuously stirred and broken to generate a fresh surface to react with a solvent, and the sediment is rapidly digested. The method also adopts a low-temperature and sectional heating and cooling mode when the arsenic is extracted by microwave, thereby avoiding the loss of arsenide caused by overhigh temperature, having short extraction time and having no obvious change of form in the microwave digestion process.
(2) Extracting 5 kinds of arsenic in the sediment by adopting a continuous step-by-step extraction method, and firstly extracting adsorption type arsenic (A-As) by adopting 1.0mol/L ammonium chloride solution; then extracting aluminum type arsenic (Al-As) by adopting 0.5mol/L ammonium fluoride solution; namely ferric arsenate, and then extracting iron-type arsenic (Fe-As) by adopting 0.5mol/L NaOH solution; then extracting calcium type arsenic (Ca-As) by using 0.5mol/L sulfuric acid solution; and finally, the coated arsenic (O-As) is digested by nitric acid-sulfuric acid-perchloric acid, and the arsenic in the sediment can be completely digested and released by the method, so that the accuracy of measuring the arsenic content is improved.
Detailed Description
For a better understanding of the present invention, the following examples are given to illustrate, but not to limit the scope of the present invention.
The new method for detecting total arsenic of heavy metal in sediment by using atomic fluorescence photometer, which is described in the following embodiment, comprises the following steps:
s1: digestion of the sediment: drying the sediment at 50-60 ℃ to constant weight, screening a part with the particle size smaller than 65 mu m as a sample, performing closed microwave digestion in a Teflon TFM digestion tank, accurately weighing the sediment, putting the sediment into the Teflon TFM microwave digestion tank, adding 15mL of phosphoric acid solution, covering a cover, sealing, and putting the sediment into a microwave digestion system for auxiliary extraction. The microwave digestion program is that the temperature is increased to 90-95 ℃ from room temperature within 10min, the microwave digestion tank is kept at 90-95 ℃ for 15-20min, the microwave digestion tank is opened when the temperature is reduced to below 30 ℃, the microwave digestion tank is cleaned by deionized water for 3 times, the microwave digestion tank and digestion liquid are poured into a centrifuge tube together, centrifugal separation is carried out, the rotation speed of the centrifugal separation is 5000rpm, and the separation time is 10 min; metering the volume of the upper layer extracting solution to 25mL, and filtering the upper layer extracting solution through a cellulose acetate filter membrane with the aperture of 0.22 mu m to obtain a sample;
s2: extracting a sample by using 1.0mol/L ammonium chloride solution to obtain a first arsenic solution; extracting the first arsenic solution by adopting 0.5mol/L ammonium fluoride solution to obtain a second arsenic solution; extracting the second arsenic solution by using 0.5mol/L sodium hydroxide solution to obtain a third arsenic solution; extracting the third arsenic solution by using a 0.5mol/L sulfuric acid solution to obtain a fourth arsenic solution, and extracting the fourth arsenic solution by using a nitric acid-sulfuric acid-perchloric acid mixed solution to obtain a sample solution;
s3: transferring the sample solution into a test tube containing a solution to be detected by an atomic fluorescence spectrophotometer, adding 0.5g of thiourea powder, covering a plug, vibrating, standing for 30-50min, and measuring after the sample is fully reduced.
S4: preparing standard solution: preparing arsenic standard solution with the following concentration in a 100mL volumetric flask by using nitric acid aqueous solution:
a.0.00ng/mL，1.00ng/mL，2.00ng/mL，4.00ng/mL，8.00ng/mL，10.00ng/mL；
b.0.00ng/mL，5.00ng/mL，10.00ng/mL，20.00ng/mL，40.00ng/mL，50ng/mL；
respectively adding reduction masking agent thiourea powder, standing at room temperature for 30min, respectively introducing each arsenic standard solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity of arsenic, and drawing two working curves; and introducing each sample solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity corresponding to arsenic in the sample solution, and determining the content of the arsenic according to the working curve.
Example 1
A novel method for detecting total arsenic of heavy metal in sediment by using an atomic fluorescence spectrophotometer comprises the following steps:
s1: digestion of the sediment: drying the sediment at 50 ℃ to constant weight, screening a part with the particle size of less than 65 mu m as a sample, performing closed microwave digestion in a Teflon TFM digestion tank, accurately weighing the sediment, putting the sediment into the Teflon TFM microwave digestion tank, adding 15mL of phosphoric acid solution, covering a cover, sealing, and putting the sediment into a microwave digestion system for auxiliary extraction. The microwave digestion program is that the temperature is increased to 95 ℃ from room temperature within 10min, the temperature is kept at 95 ℃ for 18min, the microwave digestion tank is opened when the temperature is reduced to below 30 ℃, deionized water is used for cleaning the microwave digestion tank for 3 times, the microwave digestion tank and digestion liquid are poured into a centrifuge tube together, centrifugal separation is carried out, the rotation speed of the centrifugal separation is 5000rpm, and the separation time is 10 min; metering the volume of the upper layer extracting solution to 25mL, and filtering the upper layer extracting solution through a cellulose acetate filter membrane with the aperture of 0.22 mu m to obtain a sample;
s2: extracting a sample by using 1.0mol/L ammonium chloride solution to obtain a first arsenic solution; extracting the first arsenic solution by adopting 0.5mol/L ammonium fluoride solution to obtain a second arsenic solution; extracting the second arsenic solution by using 0.5mol/L sodium hydroxide solution to obtain a third arsenic solution; extracting the third arsenic solution by using a 0.5mol/L sulfuric acid solution to obtain a fourth arsenic solution, and extracting the fourth arsenic solution by using a nitric acid-sulfuric acid-perchloric acid mixed solution to obtain a sample solution;
s3: transferring the sample solution into a test tube containing a solution to be detected by an atomic fluorescence spectrophotometer, adding 0.5g of thiourea powder, covering a plug, oscillating, standing for 40min, and measuring after the sample is fully reduced.
S4: preparing standard solution: preparing arsenic standard solution with the following concentration in a 100mL volumetric flask by using nitric acid aqueous solution:
a.0.00ng/mL，1.00ng/mL，2.00ng/mL，4.00ng/mL，8.00ng/mL，10.00ng/mL；
b.0.00ng/mL，5.00ng/mL，10.00ng/mL，20.00ng/mL，40.00ng/mL，50ng/mL；
respectively adding reduction masking agent thiourea powder, standing at room temperature for 30min, respectively introducing each arsenic standard solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity of arsenic, and drawing two working curves; and introducing each sample solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity corresponding to arsenic in the sample solution, and determining the content of the arsenic according to the working curve.
Example 2
A novel method for detecting total arsenic of heavy metal in sediment by using an atomic fluorescence spectrophotometer comprises the following steps:
s1: digestion of the sediment: drying the sediment at 55 ℃ to constant weight, screening a part with the particle size of less than 65 mu m as a sample, performing closed microwave digestion in a Teflon TFM digestion tank, accurately weighing the sediment, putting the sediment into the Teflon TFM microwave digestion tank, adding 15mL of phosphoric acid solution, covering a cover, sealing, and putting the sediment into a microwave digestion system for auxiliary extraction. The microwave digestion procedure is that the temperature is increased to 90 ℃ from room temperature within 10min, the temperature is kept for 20min under the condition of 90 ℃, the microwave digestion tank is opened when the temperature is reduced to below 30 ℃, deionized water is used for cleaning the microwave digestion tank for 3 times, the microwave digestion tank and digestion liquid are poured into a centrifuge tube together, centrifugal separation is carried out, the rotating speed of the centrifugal separation is 5000rpm, and the separation time is 10 min; metering the volume of the upper layer extracting solution to 25mL, and filtering the upper layer extracting solution through a cellulose acetate filter membrane with the aperture of 0.22 mu m to obtain a sample;
s2: extracting a sample by using 1.0mol/L ammonium chloride solution to obtain a first arsenic solution; extracting the first arsenic solution by adopting 0.5mol/L ammonium fluoride solution to obtain a second arsenic solution; extracting the second arsenic solution by using 0.5mol/L sodium hydroxide solution to obtain a third arsenic solution; extracting the third arsenic solution by using a 0.5mol/L sulfuric acid solution to obtain a fourth arsenic solution, and extracting the fourth arsenic solution by using a nitric acid-sulfuric acid-perchloric acid mixed solution to obtain a sample solution;
s3: transferring the sample solution into a test tube containing a solution to be detected by an atomic fluorescence spectrophotometer, adding 0.5g of thiourea powder, covering a plug, oscillating, standing for 50min, and measuring after the sample is fully reduced.
S4: preparing standard solution: preparing arsenic standard solution with the following concentration in a 100mL volumetric flask by using nitric acid aqueous solution:
a.0.00ng/mL，1.00ng/mL，2.00ng/mL，4.00ng/mL，8.00ng/mL，10.00ng/mL；
b.0.00ng/mL，5.00ng/mL，10.00ng/mL，20.00ng/mL，40.00ng/mL，50ng/mL；
respectively adding reduction masking agent thiourea powder, standing at room temperature for 30min, respectively introducing each arsenic standard solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity of arsenic, and drawing two working curves; and introducing each sample solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity corresponding to arsenic in the sample solution, and determining the content of the arsenic according to the working curve.
Example 3
A novel method for detecting total arsenic of heavy metal in sediment by using an atomic fluorescence spectrophotometer comprises the following steps:
s1: digestion of the sediment: drying the sediment at 60 ℃ to constant weight, screening a part with the particle size of less than 65 mu m as a sample, performing closed microwave digestion in a Teflon TFM digestion tank, accurately weighing the sediment, putting the sediment into the Teflon TFM microwave digestion tank, adding 15mL of phosphoric acid solution, covering a cover, sealing, and putting the sediment into a microwave digestion system for auxiliary extraction. The microwave digestion procedure is that the temperature is increased to 93 ℃ from room temperature within 10min, the temperature is kept at 93 ℃ for 15min, the microwave digestion tank is opened when the temperature is reduced to below 30 ℃, deionized water is used for cleaning the microwave digestion tank for 3 times, the microwave digestion tank and digestion liquid are poured into a centrifuge tube together, centrifugal separation is carried out, the rotating speed of the centrifugal separation is 5000rpm, and the separation time is 10 min; metering the volume of the upper layer extracting solution to 25mL, and filtering the upper layer extracting solution through a cellulose acetate filter membrane with the aperture of 0.22 mu m to obtain a sample;
s2: extracting a sample by using 1.0mol/L ammonium chloride solution to obtain a first arsenic solution; extracting the first arsenic solution by adopting 0.5mol/L ammonium fluoride solution to obtain a second arsenic solution; extracting the second arsenic solution by using 0.5mol/L sodium hydroxide solution to obtain a third arsenic solution; extracting the third arsenic solution by using a 0.5mol/L sulfuric acid solution to obtain a fourth arsenic solution, and extracting the fourth arsenic solution by using a nitric acid-sulfuric acid-perchloric acid mixed solution to obtain a sample solution;
s3: transferring the sample solution into a test tube containing a solution to be detected by an atomic fluorescence spectrophotometer, adding 0.5g of thiourea powder, covering a plug, oscillating, standing for 30min, and measuring after the sample is fully reduced.
S4: preparing standard solution: preparing arsenic standard solution with the following concentration in a 100mL volumetric flask by using nitric acid aqueous solution:
a.0.00ng/mL，1.00ng/mL，2.00ng/mL，4.00ng/mL，8.00ng/mL，10.00ng/mL；
b.0.00ng/mL，5.00ng/mL，10.00ng/mL，20.00ng/mL，40.00ng/mL，50ng/mL；
respectively adding reduction masking agent thiourea powder, standing at room temperature for 30min, respectively introducing each arsenic standard solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity of arsenic, and drawing two working curves; and introducing each sample solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity corresponding to arsenic in the sample solution, and determining the content of the arsenic according to the working curve.
Example 4
A novel method for detecting total arsenic of heavy metal in sediment by using an atomic fluorescence spectrophotometer comprises the following steps:
s1: digestion of the sediment: drying the sediment at 60 ℃ to constant weight, screening a part with the particle size of less than 65 mu m as a sample, performing closed microwave digestion in a Teflon TFM digestion tank, accurately weighing the sediment, putting the sediment into the Teflon TFM microwave digestion tank, adding 15mL of phosphoric acid solution, covering a cover, sealing, and putting the sediment into a microwave digestion system for auxiliary extraction. The microwave digestion program is that the temperature is increased to 95 ℃ from room temperature within 10min, the temperature is kept at 95 ℃ for 20min, the microwave digestion tank is opened when the temperature is reduced to below 30 ℃, deionized water is used for cleaning the microwave digestion tank for 3 times, the microwave digestion tank and digestion liquid are poured into a centrifuge tube together, centrifugal separation is carried out, the rotation speed of the centrifugal separation is 5000rpm, and the separation time is 10 min; metering the volume of the upper layer extracting solution to 25mL, and filtering the upper layer extracting solution through a cellulose acetate filter membrane with the aperture of 0.22 mu m to obtain a sample;
s2: extracting a sample by using 1.0mol/L ammonium chloride solution to obtain a first arsenic solution; extracting the first arsenic solution by adopting 0.5mol/L ammonium fluoride solution to obtain a second arsenic solution; extracting the second arsenic solution by using 0.5mol/L sodium hydroxide solution to obtain a third arsenic solution; extracting the third arsenic solution by using a 0.5mol/L sulfuric acid solution to obtain a fourth arsenic solution, and extracting the fourth arsenic solution by using a nitric acid-sulfuric acid-perchloric acid mixed solution to obtain a sample solution;
s3: transferring the sample solution into a test tube containing a solution to be detected by an atomic fluorescence spectrophotometer, adding 0.5g of thiourea powder, covering a plug, oscillating, standing for 30min, and measuring after the sample is fully reduced.
S4: preparing standard solution: preparing arsenic standard solution with the following concentration in a 100mL volumetric flask by using nitric acid aqueous solution:
a.0.00ng/mL，1.00ng/mL，2.00ng/mL，4.00ng/mL，8.00ng/mL，10.00ng/mL；
b.0.00ng/mL，5.00ng/mL，10.00ng/mL，20.00ng/mL，40.00ng/mL，50ng/mL；
respectively adding reduction masking agent thiourea powder, standing at room temperature for 30min, respectively introducing each arsenic standard solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity of arsenic, and drawing two working curves; and introducing each sample solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity corresponding to arsenic in the sample solution, and determining the content of the arsenic according to the working curve.
Comparative example 1
The preparation method is basically the same as that of example 1, except that the method for preparing the novel method for detecting the total arsenic in the heavy metal in the sediment by using the atomic fluorescence photometer does not adopt microwave digestion and the method of step S2 for extraction.
Comparative example 2
The preparation method is basically the same as that of the example 1, except that the method for preparing the novel method for detecting the total arsenic in the heavy metal in the sediment by using the atomic fluorescence photometer does not adopt microwave digestion.
Comparative example 3
The preparation method is basically the same as that of example 1, except that the deposit is not extracted by the method of step S2 in the method of preparing the novel method for detecting total arsenic as a heavy metal in the deposit by atomic fluorescence photometer.
Comparative example 4
The arsenic content in the deposit was determined by the method described in example 1 of the method for determining the arsenic content in iron ore by hydride generation-atomic fluorescence spectrometry (patent No. CN201310090843.0) in chinese patent document.
Arsenic content measurements were made on the same area deposits in triplicate and averaged for each sample as in examples 1-4 and comparative examples 1-4, and the results are shown in the table below.
| Item | Sample concentration (mg/L) | Sample content (mg/kg) |
| Example 1 | 0.1048 | 10.25 |
| Example 2 | 0.1075 | 10.51 |
| Example 3 | 0.1012 | 10.02 |
| Example 4 | 0.1023 | 10.08 |
| Comparative example 1 | 0.1036 | 9.23 |
| Comparative example 2 | 0.1029 | 9.45 |
| Comparative example 3 | 0.1032 | 9.38 |
| Comparative example 4 | 0.1027 | 9.36 |
From the above table, it can be seen that: (1) as can be seen from the data of examples 1-4 and comparative example 4, the accuracy of the arsenic content in the measured deposits of examples 1-4 is significantly higher than the accuracy of the arsenic content in the measured deposits of comparative example 4.
(2) According to the microwave digestion treatment method, the sediment is subjected to microwave digestion treatment, and under the action of a microwave field, polar molecules absorbing microwaves are quickly turned and directionally arranged, so that high-speed collision and friction are generated among the molecules, high heat is generated, the surface layer of the sediment is continuously stirred and broken to generate a fresh surface to react with a solvent, and the sediment is rapidly digested. The method also adopts a low-temperature and sectional heating and cooling mode when the arsenic is extracted by microwave, thereby avoiding the loss of arsenide caused by overhigh temperature, having short extraction time and having no obvious change of form in the microwave digestion process.
(3) Extracting 5 kinds of arsenic in the sediment by adopting a continuous step-by-step extraction method, and firstly extracting adsorption type arsenic (A-As) by adopting 1.0mol/L ammonium chloride solution; then extracting aluminum type arsenic (Al-As) by adopting 0.5mol/L ammonium fluoride solution; namely ferric arsenate, and then extracting iron-type arsenic (Fe-As) by adopting 0.5mol/L NaOH solution; then extracting calcium type arsenic (Ca-As) by using 0.5mol/L sulfuric acid solution; and finally, the coated arsenic (O-As) is digested by nitric acid-sulfuric acid-perchloric acid, and the arsenic in the sediment can be completely digested and released by the method, so that the accuracy of measuring the arsenic content is improved.
The above description should not be taken as limiting the invention to the embodiments, but rather, as will be apparent to those skilled in the art to which the invention pertains, numerous simplifications or substitutions may be made without departing from the spirit of the invention, which shall be deemed to fall within the scope of the invention as defined by the claims appended hereto.
Claims (7)
1. A novel method for detecting total arsenic of heavy metal in sediment by an atomic fluorescence spectrophotometer is characterized by comprising the following steps:
s1: digestion of the sediment: drying the sediment to constant weight, and performing closed microwave digestion in a Teflon TFM digestion tank to obtain a sample;
s2: extracting a sample by using 1.0mol/L ammonium chloride solution to obtain a first arsenic solution; extracting the first arsenic solution by adopting 0.5mol/L ammonium fluoride solution to obtain a second arsenic solution; extracting the second arsenic solution by using 0.5mol/L sodium hydroxide solution to obtain a third arsenic solution; extracting the third arsenic solution by using a 0.5mol/L sulfuric acid solution to obtain a fourth arsenic solution, and extracting the fourth arsenic solution by using a nitric acid-sulfuric acid-perchloric acid mixed solution to obtain a sample solution;
s3: transferring the sample solution into a test tube containing a solution to be detected by an atomic fluorescence spectrophotometer, adding 0.5g of thiourea powder, covering a plug, vibrating, standing for 30-50min, and measuring after the sample is fully reduced.
2. The novel method for detecting the total arsenic of the heavy metal in the sediment by using the atomic fluorescence photometer as claimed in claim 1, which is characterized by further comprising the following steps of preparing a standard solution: preparing arsenic standard solution with the following concentration in a 100mL volumetric flask by using nitric acid aqueous solution:
a.0.00ng/mL，1.00ng/mL，2.00ng/mL，4.00ng/mL,8.00ng/mL，10.00ng/mL；
b.0.00ng/mL，5.00ng/mL，10.00ng/mL，20.00ng/mL，40.00ng/mL，50ng/mL；
respectively adding a reduction masking agent, standing at room temperature for 30min, respectively introducing each arsenic standard solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity of arsenic, and drawing two working curves; and introducing each sample solution into an atomic fluorescence spectrophotometer, measuring the fluorescence intensity corresponding to arsenic in the sample solution, and determining the content of the arsenic according to the working curve.
3. The novel method for detecting total arsenic as heavy metal in sediment by atomic fluorescence photometer as claimed in claim 1, wherein the sediment is dried at 50-60 ℃ in step S1, and the part with particle size less than 65 μm is screened as the sample.
4. The novel method for detecting the total arsenic in the heavy metal in the sediment by using the atomic fluorescence spectrophotometer according to claim 1, wherein the microwave digestion in the step S1 is that the sediment is accurately weighed and placed in a microwave digestion tank of Teflon TFM, 15mL of phosphoric acid solution is added, a cover is covered, sealing is carried out, and the microwave digestion system is used for assisting extraction.
5. The novel method for detecting the total arsenic in the sediment by using the atomic fluorescence photometer as claimed in claim 4, wherein the microwave digestion procedure comprises the steps of increasing the temperature from room temperature to 90-95 ℃ within 10min, keeping the temperature at 90-95 ℃ for 15-20min, opening the microwave digestion tank when the temperature is reduced to below 30 ℃, washing the microwave digestion tank for 3 times by using deionized water, pouring the microwave digestion tank and a digestion solution into a centrifuge tube, carrying out centrifugal separation, fixing the volume of an upper layer extracting solution to 25mL, and filtering the upper layer extracting solution by using a cellulose acetate filter membrane with the aperture of 0.22 μm.
6. The novel method for detecting total arsenic in heavy metal in sediment by atomic fluorescence photometer as claimed in claim 5, wherein the rotation speed of the centrifugal separation is 5000rpm, and the separation time is 10 min.
7. The novel method for detecting total arsenic as heavy metal in sediment by atomic fluorescence photometer as claimed in claim 2, wherein the reduction masking agent is thiourea powder.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006177874A (en) * | 2004-12-24 | 2006-07-06 | Shimadzu Corp | Sample pretreatment method for arsenic analysis by every chemical form |
| CN103196880A (en) * | 2013-03-21 | 2013-07-10 | 内蒙古包钢钢联股份有限公司 | Method for determining content of arsenic in iron ore by using hydride generation-atomic fluorescence spectroscopy |
| CN105758830A (en) * | 2016-02-25 | 2016-07-13 | 江苏省海洋水产研究所 | Method for measuring content of total arsenic by digesting marine product in steps through microwave humidifying method |
| CN111665228A (en) * | 2020-06-09 | 2020-09-15 | 张振江 | Electric heating plate digestion-centrifugation-atomic fluorescence determination method for total arsenic in soil |
-
2022
- 2022-01-13 CN CN202210039518.0A patent/CN114184565A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006177874A (en) * | 2004-12-24 | 2006-07-06 | Shimadzu Corp | Sample pretreatment method for arsenic analysis by every chemical form |
| CN103196880A (en) * | 2013-03-21 | 2013-07-10 | 内蒙古包钢钢联股份有限公司 | Method for determining content of arsenic in iron ore by using hydride generation-atomic fluorescence spectroscopy |
| CN105758830A (en) * | 2016-02-25 | 2016-07-13 | 江苏省海洋水产研究所 | Method for measuring content of total arsenic by digesting marine product in steps through microwave humidifying method |
| CN111665228A (en) * | 2020-06-09 | 2020-09-15 | 张振江 | Electric heating plate digestion-centrifugation-atomic fluorescence determination method for total arsenic in soil |
Non-Patent Citations (2)
| Title |
|---|
| 武斌 等: "石灰性土壤中砷形态分级方法的比较及其最佳方案" * |
| 黄清辉 等: "2006年春季长江口砷形态分析及其生物有效性" * |
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