Sample preparation method of nickel-aluminum alloy for ICP-OES analysis

Abstract

The invention provides a sample preparation method of a nickel-aluminum alloy for ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometer) analysis. The sample preparation method comprises the following steps: (1) mixing the nickel-aluminum alloy with a composite acid solution to obtain a mixed material; (2) carrying out heating treatment on the mixed material, and carrying out constant volume treatment to obtain a sample preparation solution; wherein the temperature of the heating treatment is 80-90 DEG C. According to the sample preparation method, the alloy can be fully dissolved, the obtained sample preparation solution can be directly used for ICP-OES detection, element loss is avoided in the sample preparation process, and the detection precision is high.

Description

Technical Field

[0001] The invention belongs to the technical field of analysis and testing, and relates to a sample preparation method of a nickel-aluminum alloy for ICP-OES analysis. Background Art

[0002] Nickel-aluminum alloy is a new type of metal-based high-temperature resistant material with excellent high-temperature resistance. Its yield strength will increase with the increase of temperature, and it has good resistance to high-temperature oxidation. It also has the advantages of high elastic modulus, high rigidity and low density. Its heat resistance is between that of high-temperature alloys and ceramic materials. Its properties have semiconductor properties, superconducting properties, and magnetic properties. It has high application value in industry, such as in aviation, electronics, and machinery manufacturing.

[0003] The ratio of the two metal elements in nickel-aluminum alloy is an important parameter affecting its performance. The commonly used nickel-aluminum alloy testing equipment is the inductively coupled plasma optical emission spectrometer (ICP-OES). ICP-OES has less interference, stable signal, and simple operation. Before testing, you only need to dissolve it with acid and then test it on the machine. ICP-OES is mainly used to detect most metal elements and some non-metal elements.

[0004] CN103411960A discloses a method for determining the content of multiple elements in high-silicon low-alloy steel using an ICP spectrometer, comprising the following steps: (i) preparing a sample solution using a sample to be tested; (ii) preparing a working curve solution using high-purity iron, nitric acid solution and national standard solutions of silicon, manganese, nickel, chromium and copper elements; (iii) spectral measurement: using an ICP spectrometer, selecting the best analytical spectral lines of silicon, manganese, nickel, chromium and copper elements, sequentially determining the spectral intensity of each element in the working curve solution, and drawing a working curve of each element, determining the spectral intensity of silicon, manganese, nickel, chromium and copper elements in the sample solution, and obtaining the content of each element from the working curve. The method analyzes multiple elements, but does not involve the dissolution of raw materials, and whether the raw materials can be fully dissolved directly affects the accuracy of the final measurement.

[0005] CN108872195A discloses a method for determining the content of lead, tin and bismuth in an aluminum alloy by ICP-OES. The method adopts inductively coupled plasma emission spectrometry to determine the content of lead, tin and bismuth in the aluminum alloy LD7-4. The method dilutes hydrochloric acid with a volume ratio of water to hydrochloric acid of 1:1, and then adds nitric acid to dissolve the sample in a ratio of 10:1 between the diluted hydrochloric acid and nitric acid; selects the best analysis line by successively considering the analysis line with the lowest interference, the line with a strong signal and a low background; draws a working curve after adding alloy elements after using high-purity aluminum with a mass fraction of more than 99.99% as a base, and adjusts the main working parameters of the instrument that may affect the test results.

[0006] Nickel is more active in chemical properties, but more stable than iron. It is difficult to oxidize in the air at room temperature and is not easy to react with concentrated nitric acid. Aluminum is an active metal. In dry air, a dense oxide film about 5nm thick is immediately formed on the surface of aluminum, which prevents further oxidation and is resistant to water. However, aluminum powder mixed with air burns violently and emits a dazzling white flame. Molten aluminum can react violently with water, and aluminum is amphoteric, highly soluble in strong alkali and dilute acid. It is insoluble in water, but can react slowly with hot water to form aluminum hydroxide. Conventional sample preparation methods can only completely dissolve nickel or aluminum, and it is difficult to completely dissolve the alloy, resulting in a large deviation between the test results and the actual results, affecting the analysis effect. Summary of the invention

[0007] The object of the present invention is to provide a sample preparation method for nickel-aluminum alloy for ICP-OES analysis. The sample preparation method of the present invention can fully dissolve the alloy, and the obtained sample preparation solution can be directly used for ICP-OES detection. There is no element loss in the sample preparation process, and the accuracy of the detection is high.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a method for preparing a nickel-aluminum alloy for ICP-OES analysis, the method comprising the following steps:

[0010] (1) mixing a nickel-aluminum alloy with a composite acid solution to obtain a mixed material;

[0011] (2) heating the mixed material and then performing a volume determination to obtain a sample preparation solution;

[0012] The temperature of the heating treatment is 80°C to 90°C, for example, 80°C, 82°C, 85°C, 88°C or 90°C, etc., and is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0013] The present invention uses a composite acid to fully dissolve the nickel-aluminum alloy at a specific temperature to obtain a clear and transparent sample preparation solution, which meets the detection standard of ICP-OES. The element loss in the sample preparation process is small, the operation steps are simple, and the accuracy of ICP-OES analysis can be significantly improved.

[0014] Preferably, the nickel-aluminum alloy in step (1) is washed and dried before mixing.

[0015] Preferably, the washing comprises acid washing and ethanol washing.

[0016] Preferably, the pickling detergent comprises dilute hydrochloric acid and / or dilute nitric acid.

[0017] Preferably, the mass concentration of the dilute hydrochloric acid is 8% to 10%.

[0018] Preferably, the mass concentration of the dilute nitric acid is 15% to 20%.

[0019] Preferably, the ethanol washing time is 5 min to 15 min, for example, 5 min, 8 min, 10 min, 12 min or 15 min, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0020] Preferably, the composite acid solution in step (1) comprises concentrated hydrochloric acid and concentrated nitric acid.

[0021] Preferably, the mass concentration of the concentrated hydrochloric acid is 36% to 38%, for example, 36%, 36.5%, 37%, 37.5% or 38%, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0022] Preferably, the mass concentration of the concentrated nitric acid is 65% to 68%, for example, 65%, 65.5%, 66%, 67% or 68%, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0023] Preferably, the volume ratio of concentrated hydrochloric acid to concentrated nitric acid is (2-4):1, for example: 2:1, 2.5:1, 3:1, 3.5:1 or 4:1, etc., not limited to the listed values, other unlisted values ​​within the numerical range are also applicable, preferably (2.5-3.5):1.

[0024] Preferably, the mass volume ratio of the nickel-aluminum alloy to the composite acid solution in step (1) is 20 g / L to 30 g / L, for example: 20 g / L, 22 g / L, 25 g / L, 28 g / L or 30 g / L, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0025] Preferably, the heating treatment time in step (2) is 15 min to 25 min, for example, 15 min, 18 min, 20 min, 22 min or 25 min, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0026] As a preferred embodiment of the present invention, the sample preparation method comprises the following steps:

[0027] (1) After pickling and ethanol washing, the nickel-aluminum alloy is mixed with a composite acid solution at a mass volume ratio of 20 g / L to 30 g / L to obtain a mixed material, wherein the composite acid solution comprises concentrated hydrochloric acid and concentrated nitric acid at a volume ratio of (2.5 to 3.5):1;

[0028] (2) The mixed material is heated at 80° C. to 90° C. for 15 min to 25 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The sample preparation method of the present invention can fully dissolve the alloy, and the obtained sample preparation solution can be directly used for ICP-OES detection. There is no element loss during the sample preparation process, and the accuracy of the detection is high.

[0031] (2) The sample preparation method described in the present invention has a stable dissolution process, no solution splashing, and a low component loss rate, which can improve the accuracy of the test results.

[0032] (3) The nickel deviation of the sample preparation solution obtained by the sample preparation method of the present invention can be within 2.26%, and the aluminum deviation can be within 34.62%. By controlling the sample preparation conditions, the nickel deviation of the sample preparation solution can be within 1.03%, and the aluminum deviation can be within 7.69%. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0034] Example 1

[0035] This embodiment provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the method comprising the following steps:

[0036] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 10 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy, mixing 3 mL of 38% concentrated hydrochloric acid and 1 mL of 68% concentrated nitric acid to obtain a composite acid solution, and mixing 0.1 g of the pretreated nickel-aluminum alloy with the composite acid solution to obtain a mixed material;

[0037] (2) The mixed material is heated at 110° C. for 20 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0038] Example 2

[0039] This embodiment provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the method comprising the following steps:

[0040] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 5 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy, mixing 2.5 mL of 36% concentrated hydrochloric acid and 1 mL of 65% concentrated nitric acid to obtain a composite acid solution, and mixing 0.1 g of the pretreated nickel-aluminum alloy with the composite acid solution to obtain a mixed material;

[0041] (2) The mixed material is heated at 120° C. for 25 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0042] Example 3

[0043] This embodiment provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the method comprising the following steps:

[0044] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 15 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy; mixing 3.5 mL of 38% concentrated hydrochloric acid and 1 mL of 68% concentrated nitric acid to obtain a composite acid solution; taking 0.1 g of the pretreated nickel-aluminum alloy and mixing it with the composite acid solution to obtain a mixed material;

[0045] (2) The mixed material is heated at 100° C. for 15 minutes to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0046] Example 4

[0047] This embodiment provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the method comprising the following steps:

[0048] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 10 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy, mixing 3 mL of 38% concentrated hydrochloric acid and 1 mL of 68% concentrated nitric acid to obtain a composite acid solution, and mixing 0.2 g of the pretreated nickel-aluminum alloy with the composite acid solution to obtain a mixed material;

[0049] (2) The mixed material is heated at 110° C. for 20 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0050] Example 5

[0051] This embodiment provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the method comprising the following steps:

[0052] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 10 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy, mixing 1 mL of 38% concentrated hydrochloric acid and 1 mL of 68% concentrated nitric acid to obtain a composite acid solution, and mixing 0.1 g of the pretreated nickel-aluminum alloy with the composite acid solution to obtain a mixed material;

[0053] (2) The mixed material is heated at 110° C. for 20 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0054] Example 6

[0055] This embodiment provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the method comprising the following steps:

[0056] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 10 min, and then drying it to obtain a pretreated nickel-aluminum alloy, mixing 5 mL of 38% concentrated hydrochloric acid and 1 mL of 68% concentrated nitric acid to obtain a composite acid solution, and mixing 0.1 g of the pretreated nickel-aluminum alloy with the composite acid solution to obtain a mixed material;

[0057] (2) The mixed material is heated at 110° C. for 20 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0058] Comparative Example 1

[0059] This comparative example provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the sample preparation method comprising the following steps:

[0060] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 10 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy, mixing 3 mL of 38% concentrated hydrochloric acid and 1 mL of 68% concentrated nitric acid to obtain a composite acid solution, and mixing 0.1 g of the pretreated nickel-aluminum alloy with the composite acid solution to obtain a mixed material;

[0061] (2) The mixed material is heated at 70° C. for 20 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0062] Comparative Example 2

[0063] This comparative example provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the sample preparation method comprising the following steps:

[0064] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 10 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy, mixing 3 mL of 38% concentrated hydrochloric acid and 1 mL of 68% concentrated nitric acid to obtain a composite acid solution, and mixing 0.1 g of the pretreated nickel-aluminum alloy with the composite acid solution to obtain a mixed material;

[0065] (2) The mixed material is heated at 100° C. for 20 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0066] Comparative Example 3

[0067] This comparative example provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the sample preparation method comprising the following steps:

[0068] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 10 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy, taking 0.1 g of the pretreated nickel-aluminum alloy and mixing it with 4 mL of 38% concentrated hydrochloric acid to obtain a mixed material;

[0069] (2) The mixed material is heated at 110° C. for 20 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0070] Comparative Example 4

[0071] This comparative example provides a method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, the sample preparation method comprising the following steps:

[0072] (1) washing the nickel-aluminum alloy with dilute hydrochloric acid, washing it with ethanol for 10 minutes, and then drying it to obtain a pretreated nickel-aluminum alloy, taking 0.1 g of the pretreated nickel-aluminum alloy and mixing it with 4 mL of 68% concentrated nitric acid to obtain a mixed material;

[0073] (2) The mixed material is heated at 110° C. for 20 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

[0074] Performance Test:

[0075] The sample solutions obtained in the above examples and comparative examples were measured by ICP-OES analysis. The test results are shown in Table 1, where the deviation is calculated as follows: Deviation = |actual value - measured value | / actual value × 100%:

[0076] Table 1

[0077]

[0078]

[0079] As can be seen from Table 1, from Examples 1-6, the nickel deviation of the sample preparation solution obtained by the sample preparation method of the present invention can be within 2.26%, and the aluminum deviation can be within 34.62%. By controlling the sample preparation conditions, the nickel deviation of the sample preparation solution can be within 1.03%, and the aluminum deviation can be within 7.69%.

[0080] By comparing Example 1 and Example 4, it can be seen that in the sample preparation process of the nickel-aluminum alloy described in the present invention for ICP-OES analysis, the mass volume ratio of the nickel-aluminum alloy to the composite acid solution will affect the sample preparation effect. The mass volume ratio of the nickel-aluminum alloy to the composite acid solution is controlled at 20 to 30 g / L, and the effect of the sample preparation solution is better. If the amount of nickel-aluminum alloy added is too large, it will be incompletely dissolved, resulting in a low result.

[0081] By comparing Example 1 with Examples 5-6, it can be seen that in the sample preparation process of the nickel-aluminum alloy of the present invention for ICP-OES analysis, the ratio of concentrated hydrochloric acid to concentrated nitric acid will affect the sample preparation effect. The volume ratio of concentrated hydrochloric acid to concentrated nitric acid is controlled at 2.5 to 3.5:1, and the effect of preparing the sample preparation solution is better. If the proportion of concentrated hydrochloric acid is too large, incomplete dissolution will result. If the proportion of concentrated nitric acid is too large, the reaction will be too slow.

[0082] By comparing Example 1 and Comparative Examples 1-2, it can be seen that in the sample preparation process of the nickel-aluminum alloy of the present invention for ICP-OES analysis, the temperature of the heating treatment will affect the sample preparation effect. The temperature of the heating treatment is controlled at 80-90°C, and the effect of the sample preparation solution is better. If the temperature of the heating treatment is too high, the sample will volatilize, resulting in a low result. If the temperature of the heating treatment is too low, incomplete dissolution will occur.

[0083] By comparing Example 1 with Comparative Examples 3-4, it can be seen that the present invention uses a composite acid solution of concentrated nitric acid and concentrated hydrochloric acid to dissolve the nickel-aluminum alloy. If only one of the concentrated acids is used, the nickel-aluminum alloy cannot be completely dissolved, and the detection deviation is significantly increased.

[0084] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a nickel-aluminum alloy sample for ICP-OES analysis, characterized in that: The sample preparation method comprises the following steps: (1) mixing a nickel-aluminum alloy with a composite acid solution to obtain a mixed material; (2) heating the mixed material and then performing a volume determination to obtain a sample preparation solution; Wherein, the temperature of the heating treatment is 80°C to 90°C.

2. The sample preparation method according to claim 1, characterized in that: The nickel-aluminum alloy in step (1) is washed and dried before mixing; Preferably, the washing comprises acid washing and ethanol washing.

3. The sample preparation method according to claim 2, characterized in that: The pickling detergent includes dilute hydrochloric acid and / or dilute nitric acid; Preferably, the mass concentration of the dilute hydrochloric acid is 8% to 10%; Preferably, the mass concentration of the dilute nitric acid is 15% to 20%.

4. The sample preparation method according to claim 2, characterized in that: The ethanol washing time is 5 min to 15 min.

5. The sample preparation method according to any one of claims 1 to 4, characterized in that: The composite acid solution in step (1) comprises concentrated hydrochloric acid and concentrated nitric acid.

6. The sample preparation method according to claim 5, characterized in that: The mass concentration of the concentrated hydrochloric acid is 36% to 38%; Preferably, the mass concentration of the concentrated nitric acid is 65% to 68%.

7. The sample preparation method according to claim 5, characterized in that: The volume ratio of the concentrated hydrochloric acid to the concentrated nitric acid is (2-4):1, preferably (2.5-3.5):

1.

8. The sample preparation method according to any one of claims 1 to 7, characterized in that: The mass volume ratio of the nickel-aluminum alloy to the composite acid solution in step (1) is 20 g / L to 30 g / L.

9. The sample preparation method according to any one of claims 1 to 8, characterized in that: The heating time in step (2) is 15 to 25 minutes.

10. The sample preparation method according to any one of claims 1 to 9, characterized in that: The sample preparation method comprises the following steps: (1) After pickling and ethanol washing, the nickel-aluminum alloy is mixed with a composite acid solution at a mass volume ratio of 20 g / L to 30 g / L to obtain a mixed material, wherein the composite acid solution comprises concentrated hydrochloric acid and concentrated nitric acid at a volume ratio of (2.5 to 3.5):1; (2) The mixed material is heated at 80° C. to 90° C. for 15 min to 25 min to obtain a clear solution, and the clear solution is fixed to volume to obtain a sample preparation solution.

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