A diaphragm digestion treatment method

Abstract

The present invention belongs to the technical field of digestion treatment methods, and in particular relates to a diaphragm digestion treatment method, comprising the following steps: step S1, weighing a diaphragm and placing it in a digestion tube, adding a solvent, nitric acid, perchloric acid and phosphoric acid, placing it in an ultrasonic scrubber for ultrasonic treatment to obtain a first treatment liquid; step S2, placing the first treatment liquid in a graphite acid-driving furnace and heating it to obtain a second treatment liquid; step S3, placing the second treatment liquid in a microwave digester for digestion to obtain a diaphragm digestion liquid. The diaphragm digestion treatment method of the present invention can thoroughly digest the raw materials in the diaphragm, oxidizing various organic substances and dissolved particulate matter of various valence states of the test elements into a single high-valence state or converting them into easily decomposable inorganic compounds to facilitate subsequent testing. After digestion, there are no impurities and a clear solution can be obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of digestion treatment methods, and in particular relates to a diaphragm digestion treatment method. Background Art

[0002] With the increase in the types of coated diaphragms, it has become necessary to study the impurity content in the base membrane and coating materials. The current methods and published patents cannot completely digest coating materials such as PVDF and ceramic powder. The solution needs to be filtered before testing, resulting in inaccurate testing. Summary of the Invention

[0003] The object of the present invention is to provide a diaphragm digestion treatment method that can solve the problem of incomplete diaphragm digestion and inaccurate testing caused by existing technology.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A diaphragm digestion treatment method comprises the following steps:

[0006] Step S1, weighing a diaphragm and placing it in a digestion tube, adding a solvent, nitric acid, perchloric acid and phosphoric acid, and placing it in an ultrasonic washer for ultrasonic treatment to obtain a first treatment liquid;

[0007] Step S2, placing the first treatment liquid into a graphite acid-driving furnace and heating it to obtain a second treatment liquid;

[0008] Step S3: placing the second treatment liquid into a microwave digester for digestion to obtain a diaphragm digestion liquid.

[0009] The diaphragm and the mixed acid are ultrasonically treated to accelerate the dissolution of the diaphragm by the mixed acid and improve the efficiency of digestion. The liquid after ultrasonic treatment is then placed in a graphite furnace for heating to volatilize and remove the mixed acid after the reaction to obtain a second treatment liquid. The second treatment liquid is placed in a microwave digestion instrument for digestion to obtain a clear solution after the diaphragm is completely digested.

[0010] Preferably, in step S1, the volume ratio of the solvent, nitric acid, perchloric acid and phosphoric acid is 1-5:2-6:0.2-3:2-6.

[0011] Preferably, the concentration of nitric acid is 0.5-1.5 mol / L, the concentration of perchloric acid is 0.5-1.5 mol / L, and the concentration of phosphoric acid is 0.5-1.5 mol / L.

[0012] Preferably, the solvent in step S1 is one of pure water, deionized water and ultrapure water.

[0013] Preferably, the power of the ultrasonic treatment in step S1 is 250 to 350 W, and the ultrasonic treatment time is 2 to 10 minutes.

[0014] Preferably, in step S2, the heating temperature is 90-130° C., and the heating time is 30-90 minutes.

[0015] Preferably, the digestion pressure in step S3 is 2-6 MPa, the time is 80-120 minutes, and the temperature is 100-400°C.

[0016] Preferably, the mass of the diaphragm in step S1 is 0.0100 to 30.0000 g.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: the diaphragm digestion treatment method of the present invention can completely digest the raw materials in the diaphragm, and there is no impurity after digestion, and a clear solution can be obtained. The digestion oxidizes the various valence states of the test elements of various organic substances and dissolved particulate matter into a single high-valence state or converts them into easily decomposable inorganic compounds to facilitate subsequent testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the diaphragm processing of the present invention. DETAILED DESCRIPTION

[0019] The present invention will be described in further detail below with reference to specific implementation methods and the accompanying drawings, but the implementation methods of the present invention are not limited thereto.

[0020] 1. A diaphragm digestion treatment method, comprising the following steps:

[0021] Step S1, weighing a diaphragm and placing it in a digestion tube, adding a solvent, nitric acid, perchloric acid and phosphoric acid, and placing it in an ultrasonic washer for ultrasonic treatment to obtain a first treatment liquid;

[0022] Step S2, placing the first treatment liquid into a graphite acid-driving furnace and heating it to obtain a second treatment liquid;

[0023] Step S3: placing the second treatment liquid into a microwave digester for digestion to obtain a diaphragm digestion liquid.

[0024] The diaphragm digestion treatment method of the present invention can completely digest the raw materials in the diaphragm, and after digestion, there is no impurity, and a clear solution can be obtained. The digestion oxidizes the various valence states of the test elements of various organic substances and dissolved particulate matter into a single high-valence state or converts them into easily decomposable inorganic compounds to facilitate subsequent testing.

[0025] The diaphragm and the mixed acid are ultrasonically treated to accelerate the dissolution of the diaphragm by the mixed acid and improve the efficiency of digestion. The liquid after ultrasonic treatment is then placed in a graphite furnace for heating to volatilize and remove the mixed acid after the reaction to obtain a second treatment liquid. The second treatment liquid is placed in a microwave digestion instrument for digestion to obtain a clear solution after the diaphragm is completely digested.

[0026] When weighing the diaphragm, cut off the starting and ending ends of the diaphragm, use PTFE tweezers to place the wound diaphragm into the bottom of the PFA digestion tube, and accurately weigh the sample to an accuracy of 0.0001 g.

[0027] In step S1, the diaphragm includes a base membrane and a coating membrane. The coating membrane is applied to one or both surfaces of the base membrane. The equipment used for the treatment includes: a super microwave digester, a 30ml PFA digestion tube, a 1 / 10,000 analytical balance, ceramic scissors, PTFE clamps, an ultrasonic cleaner, a graphite furnace acid remover, and a Miliboo ultrapure water machine; the required reagents include: nitric acid (MOS grade), perchloric acid (MOS grade), phosphoric acid (MOS grade), and ultrapure water.

[0028] Preferably, in step S1, the volume ratio of the solvent, nitric acid, perchloric acid and phosphoric acid is 1-5:2-6:0.2-3:2-6. Preferably, the volume ratio of the solvent, nitric acid, perchloric acid and phosphoric acid is 1-5:2-6:0.2-3:2-6, 2-5:3-6:0.5-3:3-6, 2-5:2-6:0.6-3:3-6, 1-5:2-6:0.8-3:2-6, 1-5:2-6:1.2-3:2-6, 2-5:3-6:2-3:2-6, 2-5:3-6:0.2-3:2-6, 3-5:2-6:0.2-3:2-6, 3-5:3-6:0.2-3:3-6, 3-4:3-5:0.2-3:3-6.

[0029] Preferably, the concentration of nitric acid is 0.5-1.5 mol / L, the concentration of perchloric acid is 0.5-1.5 mol / L, and the concentration of phosphoric acid is 0.5-1.5 mol / L. Preferably, the concentration of nitric acid is 0.5-1.5 mol / L, 0.8-1.5 mol / L, 1.1-1.5 mol / L, 1.2-1.5 mol / L, 1.2-1.4 mol / L. Specifically, the concentration of nitric acid is 0.5 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.2 mol / L, 1.5 mol / L, and the concentration of perchloric acid is 0.5-1.5 mol / L, 0.7-1.5 mol / L, 0.9-1.5 mol / L, 1-1.5 mol / L, 1.1-1.4 mol / L, 1.2-1.4 mol / L, specifically, the concentration of perchloric acid is 0.5mol / L, 0.8mol / L, 0.9mol / L, 1.0mol / L, 1.2mol / L, and 1.5mol / L; the concentration of phosphoric acid is 0.5-1.5mol / L, 0.7-1.5mol / L, 0.9-1.5mol / L, 1-1.5mol / L, 1.1-1.4mol / L, and 1.2-1.4mol / L, specifically, the concentration of phosphoric acid is 0.5mol / L, 0.8mol / L, 0.9mol / L, 1.0mol / L, 1.2mol / L, and 1.5mol / L.

[0030] Preferably, the solvent in step S1 is one of pure water, deionized water, and ultrapure water. Preferably, the solvent is ultrapure water. Pure water and deionized water contain certain ions and organic matter, which may affect the testing of the final digested liquid. Ultrapure water contains no ions or organic matter and virtually eliminates the conductive medium, providing a basis for accurate testing of the digested liquid.

[0031] Preferably, the power of the ultrasonic treatment in step S1 is 250-350W, and the ultrasonic treatment time is 2-10 minutes. The power of the ultrasonic treatment is 250-350W, 260-340W, 280-320W, 290-320W, 300-320W, specifically, the power of the ultrasonic treatment is 250W, 280W, 290W, 300W, 320W, 350W, and the ultrasonic treatment time is 2-10 minutes, 4-10 minutes, 4-8 minutes, 4-6 minutes, specifically, the ultrasonic treatment time is 2 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes.

[0032] Preferably, in step S2, the heating temperature is 90-130° C., and the heating time is 30-90 minutes. The heating temperature is 90-130° C., 100-130° C., 105-130° C., 110-130° C., or 120-130° C. Specifically, the heating temperature is 90° C., 95° C., 100° C., 105° C., 110° C., 115° C., 120° C., or 130° C. The heating time is 30-90 minutes, 35-90 minutes, 40-90 minutes, 50-90 minutes, 50-80 minutes, or 50-80 minutes.

[0033] Preferably, the digestion pressure in step S3 is 2-6 MPa, the time is 80-120 minutes, and the temperature is 100-400° C. The digestion pressure is 2-6 MPa, 2.5-6 MPa, 3-6 MPa, 4-6 MPa, specifically, the digestion pressure is 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, and the digestion time is 80-120 minutes, 85-120 minutes, 90-110 minutes, 90-120 minutes, 100-120 minutes, 110-120 minutes, specifically, the digestion time is 80 minutes, 90 minutes, 100 minutes, 110 minutes, 120 minutes.

[0034] Preferably, the mass of the diaphragm in step S1 is 0.0100-30.0000 g. Preferably, the mass of the diaphragm is 0.0100-30.0000 g, 0.0300-30.0000 g, 0.0500-30.0000 g, 0.1000-20.0000 g, 2.0000-20.0000 g, or 5.0000-20.0000 g. Specifically, the mass of the diaphragm is 0.0100 g, 0.1000 g, 0.8000 g, 1.5000 g, 2.0000 g, 3.0000 g, 15.0000 g, 20.0000 g, or 30.0000 g.

[0035] Example 1

[0036] A diaphragm digestion treatment method comprises the following steps:

[0037] Step S1, weighing a diaphragm and placing it in a digestion tube, adding a solvent, nitric acid, perchloric acid and phosphoric acid, and placing it in an ultrasonic washer for ultrasonic treatment to obtain a first treatment liquid;

[0038] Step S2, placing the first treatment liquid into a graphite acid-driving furnace to heat the second treatment liquid;

[0039] Step S3: placing the second treatment liquid into a microwave digester for digestion to obtain a diaphragm digestion liquid.

[0040] Before weighing the diaphragm, the starting and ending ends of the diaphragm were cut off, such as Figure 1 As shown in the figure, use PTFE tweezers to place the wound septum into the bottom of the PFA digestion tube, and accurately weigh the sample to an accuracy of 0.0001 g.

[0041] Wherein, in step S1, the volume ratio of the solvent, nitric acid, perchloric acid and phosphoric acid is 2:4:1:3.

[0042] Wherein, the concentration of nitric acid is 1 mol / L, the concentration of perchloric acid is 1 mol / L, and the concentration of phosphoric acid is 1 mol / L.

[0043] Wherein, the solvent is ultrapure water.

[0044] The ultrasonic treatment power in step S1 is 280W, and the ultrasonic treatment time is 5 minutes.

[0045] Wherein, the heating temperature in step S2 is 110° C. and the heating time is 60 minutes.

[0046] The digestion pressure in step S3 is 4 MPa, the digestion time is 110 minutes, and the digestion temperature is 260°C.

[0047] Wherein, the mass of the diaphragm in step S1 is 10.0000 g.

[0048] Example 2

[0049] The difference from Example 1 is that in step S1, the volume ratio of the solvent, nitric acid, perchloric acid, and phosphoric acid is 2:4:2:3.

[0050] The rest is the same as in Example 1 and will not be described again here.

[0051] Example 3

[0052] The difference from Example 1 is that in step S1, the volume ratio of the solvent, nitric acid, perchloric acid, and phosphoric acid is 2:4:1:5.

[0053] The rest is the same as in Example 1 and will not be described again here.

[0054] Example 4

[0055] The difference from Example 1 is that in step S1, the volume ratio of the solvent, nitric acid, perchloric acid, and phosphoric acid is 2:5:1:3.

[0056] The rest is the same as in Example 1 and will not be described again here.

[0057] Example 5

[0058] The difference from Example 1 is that in step S1, the volume ratio of the solvent, nitric acid, perchloric acid, and phosphoric acid is 2:4:2:5.

[0059] The rest is the same as in Example 1 and will not be described again here.

[0060] Example 6

[0061] The difference from Example 1 is that in step S1, the volume ratio of the solvent, nitric acid, perchloric acid, and phosphoric acid is 2:5:3:5.

[0062] The rest is the same as in Example 1 and will not be described again here.

[0063] Example 7

[0064] The difference from Example 1 is that the heating temperature in step S2 is 90° C. and the heating time is 60 minutes.

[0065] The rest is the same as in Example 1 and will not be described again here.

[0066] Example 8

[0067] The difference from Example 1 is that the heating temperature in step S2 is 120° C. and the heating time is 60 minutes.

[0068] The rest is the same as in Example 1 and will not be described again here.

[0069] Example 9

[0070] The difference from Example 1 is that the heating temperature in step S2 is 90° C. and the heating time is 60 minutes.

[0071] The rest is the same as in Example 1 and will not be described again here.

[0072] Comparative Example 1

[0073] The diaphragm was directly placed into the microwave digester for digestion.

[0074] The liquids after digestion of Examples 1-9 and Comparative Example 1 were compared, and the content of solid impurities in the liquids was detected. The detection results are recorded in Table 1.

[0075] Table 1

[0076]

[0077]

[0078] It can be concluded from Table 1 that the membrane digestion treatment method of the present invention can thoroughly digest the membrane, so that the various organic substances and various valence states of the elements to be tested of the dissolved particles in the membrane are oxidized into a single high-valence state or converted into an inorganic compound that is easy to decompose, and dissolved in a solvent to obtain a clear liquid, and the test is accurate. By comparing Examples 1-9 with Comparative Example 1, it can be concluded that the solid impurity content in the liquid obtained by the membrane hydrolysis treatment method of the present invention is less than 0.0001%, and its impurity content is negligible, so it does not affect the accuracy of the test. The clear liquid obtained by the digestion treatment of this Example 1 has no impurities in the liquid and the test accuracy is high. The solid impurity content of Comparative Example 1 is 0.21%, and solid impurities are clearly seen, which affects the accuracy of the content test of the elements to be tested. By comparing Examples 1-6, it can be concluded that when the volume ratio of the solvent, nitric acid, perchloric acid, and phosphoric acid in step S1 is set to 2:5:3:5, the membrane can be thoroughly digested and the various acid reagents used can be saved, saving costs and having a better effect. By comparing Examples 1 and 7-9, it can be concluded that when the heating temperature in step S2 is set to 110° C. and the heating time is set to 60 minutes, the digestion effect is better, energy consumption is saved, cost is saved, and the effect is better.

[0079] Based on the disclosure and teachings of the above description, those skilled in the art will be able to make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the above specific embodiments. Any obvious improvements, substitutions, or modifications made by those skilled in the art based on the present invention fall within the scope of protection of the present invention. In addition, although certain specific terms are used in this description, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims

1. A diaphragm digestion treatment method, characterized in that: The following steps are involved: Step S1, weighing a diaphragm containing PVDF and ceramic powder and placing it into a digestion tube, adding a solvent, nitric acid, perchloric acid and phosphoric acid, placing it into an ultrasonic washer for ultrasonic treatment to obtain a first treatment liquid; Step S2, placing the first treatment liquid into a graphite furnace and heating it to obtain a second treatment liquid; Step S3, placing the second treatment liquid into a microwave digester for digestion to obtain a diaphragm digestion liquid; In step S1, the volume ratio of the solvent, nitric acid, perchloric acid and phosphoric acid is 1-5:2-6:0.2-3:2-6; The concentration of the nitric acid is 0.5-1.5 mol / L, the concentration of the perchloric acid is 0.5-1.5 mol / L, and the concentration of the phosphoric acid is 0.5-1.5 mol / L; The ultrasonic treatment power in step S1 is 250-350W, and the ultrasonic treatment time is 2-10 minutes; In step S2, the heating temperature is 90-130° C. and the heating time is 30-90 minutes; The digestion pressure in step S3 is 2-6 MPa, the time is 80-120 minutes, and the temperature is 260-400°C; The solvent in step S1 is pure water.

2. The diaphragm digestion treatment method according to claim 1, characterized in that: The mass of the diaphragm in step S1 is 0.0100-30.0000 g.

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