Sodium antimonate for plasma spectrometry detection and preparation method of hydrate solution sample of sodium antimonate

Abstract

The name of the invention is sodium antimonate for plasma spectrometry detection and a preparation method of a hydrate solution sample of the sodium antimonate. Belongs to the technical field of trace impurity element detection. The method mainly solves the problems of tedious detection means, low dissolution efficiency, easy introduction of impurities and influence on sample detection accuracy in the existing method. The method mainly comprises the following steps: (1) weighing uniformly ground sodium antimonate or sodium antimonate hydrate into a plastic container which can be heated in a closed manner, and then adding hydrofluoric acid and hydrochloric acid or / and nitric acid into the container; (2) sealing a container filled with sodium antimonate or sodium antimonate hydrate, hydrofluoric acid and hydrochloric acid or / and nitric acid, heating at low temperature to completely dissolve the sample, cooling to room temperature, transferring to a volumetric flask, diluting to the scale, and shaking uniformly to obtain a sodium antimonate or sodium antimonate hydrate solution to be detected. The method has the characteristics of small reagent dosage, high dissolution efficiency, low salinity and low spectral background, and is mainly used for determining trace impurity elements contained in sodium antimonate and hydrates thereof.

Description

Technical Field

[0001] This invention belongs to the field of trace impurity element detection technology, specifically relating to a method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry. Background Technology

[0002] Sodium antimonate (also known as sodium pyroantimonate) and its hydrates are mainly used as clarifying agents for picture tube shells and optical glass. The impurity content of these substances has a significant impact on the quality of finished glass products. Therefore, rapid and accurate detection and analysis of these impurities is an important task.

[0003] However, due to the influence of raw materials and preparation processes, sodium antimonate and its hydrates contain a variety of impurities, including but not limited to Fe, Cu, Co, Cr, As, Pb, Bi, and Cd.

[0004] HG / T3254-2010, "Sodium Antimonate Hydrated for Electronic Industry," provides existing detection methods, primarily using wet chemical methods to detect impurities in sodium antimonate and its hydrates item by item. This process is complex and time-consuming. Samples are treated with hydrobromic acid; heating removes antimony by volatilizing, but ass is also lost in the process.

[0005] Inductively coupled plasma atomic emission spectrometry (ICP-AES) is a highly efficient and accurate method for detecting trace impurities, but it requires pre-treatment of the sample into a stable solution. The literature "Determination of Trace Sb(III) in Sodium Antimonate Hydrate" also provides a method for dissolving sodium antimonate hydrate using 4 mol·L⁻¹ solution at room temperature. -1 Hydrochloric acid dissolution solves the problems of difficulty and interference associated with the classic cerium sulfate method. However, due to the volatility of hydrochloric acid, dissolution can only be performed at room temperature, resulting in low efficiency. The literature "Determination of Iron and Lead Content in Sodium Pyroantimonate by Atomic Absorption Spectrometry" uses nitric acid and tartaric acid to dissolve sodium antimonate, but this requires a large amount of tartaric acid. The increased salt content makes this dissolution method unsuitable for inductively coupled plasma spectrometry (ICP-AES). Furthermore, tartaric acid is an organic compound, requiring increased spectrometer power and affecting instrument lifespan. The literature "Study on the Method for Determining Impurities in Sodium Antimonate by ICP-AES" uses nitric acid and hydrochloric acid for dissolution, adding tartaric acid to prevent antimony hydrolysis, and then directly measuring the sample on an ICP-AES spectrometer. Existing common methods use tartaric acid to act as a complexing agent, effectively preventing antimony hydrolysis. However, the disadvantages are also obvious: sodium antimonate and its hydrates have low solubility, requiring a large amount of tartaric acid, increasing salt content, easily introducing impurities, and leading to instability in the plasma flame. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing sodium antimonate and its hydrate solution samples with low salinity, convenient sample preparation, and easy determination of trace impurity elements, so as to achieve high efficiency and accuracy when determining sodium antimonate and its hydrate impurities using methods such as inductively coupled plasma spectroscopy.

[0007] The technical solution of this invention is: a method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry, characterized by comprising the following steps: (1) Weigh the uniformly ground sodium antimonate or sodium antimonate hydrate into a heatable plastic container, and then add hydrofluoric acid, hydrochloric acid and / or nitric acid to the container. (2) After sealing the container containing sodium antimonate or sodium antimonate hydrate, hydrofluoric acid, and hydrochloric acid and / or nitric acid, heat it at low temperature to completely dissolve the sample. After cooling to room temperature, transfer it to a volumetric flask, dilute to the mark and shake well. The dissolution process of sodium antimonate or sodium antimonate hydrate is completed, and the sodium antimonate or sodium antimonate hydrate test solution is obtained.

[0008] Preferably, in step (1), the particle size of the uniformly ground sodium antimonate or sodium antimonate hydrate is <200 mesh.

[0009] Preferably, in step (1), the purity of the sodium antimonate or sodium antimonate hydrate after uniform grinding is >99%.

[0010] Preferably, in step (1), the sealed heated plastic container is a PFA digestion vessel, a microwave digestion vessel, or a hydrothermal reactor.

[0011] Preferably, in step (1), the added hydrofluoric acid is of superior purity and has a weight percentage of ≥40wt%.

[0012] Preferably, in step (1), the added hydrochloric acid is of superior purity and has a weight percentage of ≥36wt%.

[0013] Preferably, in step (1), the added nitric acid is of superior purity and has a weight percentage of ≥65wt%.

[0014] Preferably, in step (1), the mass ratio between sodium antimonate or sodium antimonate hydrate, hydrofluoric acid, hydrochloric acid and nitric acid is 1:(5-20):(1-20):(1-20), the mass ratio between sodium antimonate or sodium antimonate hydrate, hydrofluoric acid and hydrochloric acid is 1:(5-20):(1-20), or the mass ratio between sodium antimonate or sodium antimonate hydrate, hydrofluoric acid and nitric acid is 1:(5-20):(1-20).

[0015] Preferably, in step (2), low temperature refers to the temperature being controlled within the range of 200~250℃.

[0016] Preferably, in step (2), complete sample dissolution refers to heating until the solution becomes clear, in an acidic medium, using hydrofluoric acid and Sb. 5+ It forms a stable complex, effectively preventing the hydrolysis of antimony.

[0017] This invention features low reagent consumption, high dissolution efficiency, low salinity, and low spectral background. It is mainly used for the determination of trace impurity elements contained in sodium antimonate and its hydrates. Detailed Implementation

[0018] The technical solutions of this invention will be clearly and completely described below in conjunction with the content of this invention. It should be understood that the described embodiments are only some embodiments of this invention and are used only to explain the technical solutions, not to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the protection scope of this invention.

[0019] In this invention, sodium antimonate and its hydrates refer to both sodium antimonate and sodium antimonate hydrates.

[0020] Example 1: Weigh 1.0000g of sodium antimonate, with a purity of 99.95% and a particle size of less than 200 mesh, and place it in a 15ml polytetrafluoroethylene digestion vessel. Add 6mL of hydrofluoric acid with a weight percentage of ≥40wt%, 3mL of hydrochloric acid with a weight percentage of ≥36wt%, and 3mL of nitric acid with a weight percentage of ≥65wt%. Then seal the polytetrafluoroethylene digestion vessel and heat it at 230℃ for about 2 hours until the sample is completely dissolved. After cooling to room temperature, transfer it to a 100mL volumetric flask, dilute to the mark, and shake well. The sodium antimonate dissolution process is complete, and the sodium antimonate test solution is obtained.

[0021] Example 2: Weigh 1.0000g of sodium antimonate trihydrate, with a purity of 99.93% and a particle size of less than 200 mesh, and place it in a 15ml polytetrafluoroethylene digestion vessel. Add 5mL of hydrofluoric acid with a weight percentage of ≥40wt% and 6mL of hydrochloric acid with a weight percentage of ≥36wt%. Then seal the polytetrafluoroethylene digestion vessel and heat it at 240℃ for about 2 hours until the sample is completely dissolved. After cooling to room temperature, transfer it to a 100mL volumetric flask, dilute to the mark, and shake well. The sodium antimonate trihydrate dissolution process is complete, and the sodium antimonate trihydrate test solution is obtained.

[0022] Example 3: Weigh 1.0000g of sodium antimonate trihydrate, with a purity of 99.97% and a particle size of less than 200 mesh, and place it in a 15ml polytetrafluoroethylene digestion vessel. Add 6mL of hydrofluoric acid with a weight percentage of ≥40wt% and 6mL of nitric acid with a weight percentage of ≥65wt%. Then seal the polytetrafluoroethylene digestion vessel and heat it at 230℃ for about 2 hours until the sample is completely dissolved. After cooling to room temperature, transfer it to a 100mL volumetric flask, dilute to the mark, and shake well. The sodium antimonate trihydrate dissolution process is complete, and the sodium antimonate trihydrate test solution is obtained.

[0023] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the specification of the present invention should still fall within the scope of the patent of the present invention.

Claims

1. A method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry, characterized in that: Includes the following steps: (1) Weigh the uniformly ground sodium antimonate or sodium antimonate hydrate into a heatable plastic container, and then add hydrofluoric acid, hydrochloric acid and / or nitric acid to the container. (2) After sealing the container containing sodium antimonate or sodium antimonate hydrate, hydrofluoric acid, and hydrochloric acid and / or nitric acid, heat it at low temperature to completely dissolve the sample. After cooling to room temperature, transfer it to a volumetric flask, dilute to the mark and shake well. The dissolution process of sodium antimonate or sodium antimonate hydrate is completed, and the sodium antimonate or sodium antimonate hydrate test solution is obtained.

2. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (1), the particle size of the uniformly ground sodium antimonate or sodium antimonate hydrate is <200 mesh.

3. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (1), the purity of sodium antimonate or sodium antimonate hydrate after uniform grinding is >99%.

4. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (1), the sealed heated plastic container is a PFA digestion vessel, a microwave digestion vessel, or a hydrothermal reactor.

5. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (1), the added hydrofluoric acid is of superior purity and has a weight percentage of ≥40wt%.

6. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (1), the added hydrochloric acid is of superior purity and has a weight percentage of ≥36wt%.

7. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (1), the added nitric acid is of superior purity and has a weight percentage of ≥65wt%.

8. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (1), the mass ratio between sodium antimonate or sodium antimonate hydrate, hydrofluoric acid, hydrochloric acid and nitric acid is 1:(5-20):(1-20):(1-20), the mass ratio between sodium antimonate or sodium antimonate hydrate, hydrofluoric acid and hydrochloric acid is 1:(5-20):(1-20), or the mass ratio between sodium antimonate or sodium antimonate hydrate, hydrofluoric acid and nitric acid is 1:(5-20):(1-20).

9. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (2), low temperature refers to the temperature being controlled within the range of 200~250℃.

10. The method for preparing sodium antimonate and its hydrate solution samples for detection by inductively coupled plasma spectrometry according to claim 1, characterized in that: In step (2), complete dissolution of the sample means heating until the solution becomes clear. In an acidic medium, hydrofluoric acid and Sb5+ form a stable complex, which effectively prevents the hydrolysis of antimony.