KR102153160B1 - Quantitative analysis method of pd catalyst by using direct introduction of organic solvents - Google Patents

Abstract

The present invention relates to a method for quantitatively analyzing the metal composition and content of a catalyst dissolved in an organic solvent. The quantitative analysis method of the present invention significantly shortens the quantitative analysis time of the catalyst and does not measure impurities other than the catalyst without using a glass vial without undergoing decomposition by acid and ash at high temperature as a pretreatment of a catalyst sample. The content of catalyst can be determined.

Description

Quantitative analysis of Pd catalyst using direct organic solvent injection method {QUANTITATIVE ANALYSIS METHOD OF PD CATALYST BY USING DIRECT INTRODUCTION OF ORGANIC SOLVENTS}

The present invention relates to a method for quantitatively analyzing the metal composition and content of a catalyst dissolved in an organic solvent.

According to the prior art, when an inductively coupled plasma optical emission spectrometry (ICP-OES) is used for quantitative analysis of an organic or inorganic catalyst, sulfuric acid carbonation is generally used to pretreat a sample containing the catalyst. / Electric furnace ash / acid decomposition method was used. This pretreatment is to ensure that the sample is homogeneously introduced into the ICP-OES, and the sample is uniformly distributed in the aqueous solution by going through a series of pretreatment processes to remove organic substances such as sulfuric acid carbonation/ashing/acid decomposition in a high temperature electric furnace. do. However, the pretreatment process using acid decomposition takes a long time from one to two days or more, requires a skilled experimenter, and is a labor-intensive method using strong acids such as sulfuric acid and nitric acid. Accordingly, a method for rapid pretreatment and reducing the use of harmful strong acids was required. As a method to shorten the time, a pretreatment using electric furnace incineration has been proposed. In the case of a catalyst containing metals such as Pd and Cu, the incineration process at high temperature using a platinum crucible is a platinum crucible. There was a problem in that it was not possible to remove by coating. In particular, in the case of Pd, it was difficult to apply incineration in an electric furnace because it forms PdO that does not dissolve well into any acid by high-temperature incineration. As a result, there was a problem that the pretreatment time was longer to 2 to 3 days. In addition, since Na may be eluted from the glass when an acid is used in a glass vial, there is a problem in that not only Pd but also Na are measured when Pd using an acid in the glass vial is analyzed.

Accordingly, the present inventors explored a method in which such a problem of the prior art does not occur, and by using a method of directly injecting an organic solvent, the organic or inorganic catalyst could be pretreated within 10 minutes. Since the pretreatment method according to the present invention does not use a strong acid and a heating process and does not use a glass vial, not only the above-described disadvantages can be avoided, but also the quantification of Na, which was impossible when using a glass vial, is possible.

Accordingly, in the present invention, when quantitatively analyzing an organic or inorganic catalyst by ICP-OES, it is possible to provide a new method using an organic solvent for pretreatment of the catalyst.

An object of the present invention is to provide a method capable of shortening the analysis time of the catalyst during quantitative analysis of an organic or inorganic catalyst using ICP-OES.

In order to achieve the above object, the present invention in one embodiment,

Weighing a sample containing an organic or inorganic catalyst and introducing it into a plastic container;

Adding an organic solvent to the sample; And

It provides a quantitative analysis method of the catalyst in the sample, comprising the step of introducing a mixture of the sample and the solvent directly into ICP-OES. The quantitative analysis method of the present invention does not undergo decomposition by acid and ash at high temperature as a pretreatment of a catalyst sample, and does not use a glass vial.

In one embodiment, the catalyst is selected from Pd, Cu, Na, and the like.

In one embodiment, as the plastic container, a plastic container made of a material such as polyethylene (PE), polypropylene (PP), polystyrene (PS), perfluoroalkoxy (PFA) insoluble in an organic solvent may be used, and Among them, a centrifuge tube made of PP material, which is most easily available, can be used.

In one embodiment, the organic solvent is a polar organic solvent.

In one embodiment, the organic solvent is N-methylpyrrolidone (NMP), propylene glycol methyl ether acetate (PGMEA), or isopropyl alcohol (IPA) alone, which can be mixed with water due to its high polarity, or sampled by ICP-OES. It may be a mixture of two or more of the above-described organic solvents for controlling the viscosity to more evenly inject or controlling the polarity for dissolving the sample.

In one embodiment, the ratio of the catalyst-containing sample and the organic solvent is 1:1000 to 1:10000 by weight, but may be changed according to the content of the catalyst material or the range of the calibration line.

In one embodiment, an internal standard method of reducing an error of a measurement value due to a change in the amount of sample introduced or plasma change of ICP-OES may be used by adding an internal standard material of known concentration to the catalyst-containing sample and the organic solvent. In one embodiment, the internal standard material may include scandium (Sc).

In the quantitative analysis method of the present invention, a mixed solution of an organic solvent and a catalyst is directly introduced into ICP-OES without undergoing acid and high temperature pretreatment of the catalyst sample, so that the catalyst in the sample can be quantitatively analyzed in a shorter time compared to the prior art.

1 shows a Pd calibration curve according to the NMP solvent injection method according to the present invention.
Figure 2 is a comparison of the Pd peak by the NMP solvent-based measurement method according to the present invention versus the conventional ultrapure water (deionized water)-based measurement method.

Hereinafter, the present invention will be described in more detail.

Terms and words used in this specification and claims should not be construed as being limited to their usual or dictionary meanings, and that the inventor can appropriately define the concept of terms in order to describe his own invention in the best way. Based on the principle, it should be interpreted as a meaning and concept consistent with the technical idea of the present invention.

In one embodiment, the quantitative analysis method of the present invention,

Weighing a sample containing an organic or inorganic catalyst and introducing it into a plastic container;

Adding an organic solvent to the sample; And

And introducing the mixture of the sample and the solvent directly into the ICP-OES.

In one embodiment, the catalyst is selected from Pd, Cu, Na, and the like. In another embodiment, the catalyst is Pd.

In one embodiment, as the plastic container, any plastic container made of a material such as PE, PP, PS, PFA may be used, and among them, a centrifuge tube made of PP material, which is most easily obtained, may be used.

In one embodiment, the organic solvent is a polar organic solvent.

In one embodiment, the organic solvent is highly polar and can be mixed with water N-methylpyrrolidone (NMP), propylene glycol methyl ether acetate (PGMEA), or isopropyl alcohol (IPA) alone, or two or more of them. It can be a mixture.

In one embodiment, the ratio of the catalyst-containing sample and the organic solvent is 1:1000 to 1:10000 by weight, but may be changed according to the content of the catalyst material or the range of the calibration line.

In one embodiment, an internal standard method of reducing an error of a measurement value due to a change in the amount of sample introduced or plasma change of ICP-OES may be used by adding an internal standard material of known concentration to the catalyst-containing sample and the organic solvent. In one embodiment, the internal standard material may include scandium (Sc).

The quantitative analysis method of the present invention does not undergo decomposition by acid and ash at high temperature as a pretreatment of a catalyst sample. For this reason, there is an effect of shortening the analysis time by omitting a prolonged pretreatment process, which was a problem in the quantitative analysis of the catalyst. In addition, in the present invention, by using a plastic container instead of a glass vial as a container for analyzing the catalyst sample, the disadvantage that impurity Na is eluted from the glass when using an acid is prevented, so that an accurate content analysis of the catalyst in the sample is possible.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

<Example>

One. Acid decomposition method (conventional method-comparative example)

1.1 ICP-OES plasma conditions

1) Plasma gas flow rate: 10L/min

2) Auxiliary gas flow rate: 0.2L/min

3) Nebulizer gas flow rate: 0.8L/min

4) RF power 1300W

5) Pump flow rate: 1.5 mL/min

1.2 Pre-treatment method

1) Static electricity was removed from 40 mL glass vials and Pd-containing samples using an electrostatic gun. 20 mg of the sample was weighed and put into the glass vial.

2) 1 mL of sulfuric acid was added to the sample, and the mixture was heated overnight while raising the temperature to 200°C, 250°C, 300°C, and 350°C on a hot plate. If there was no white smoke after heating, 1 mL of nitric acid and one drop of hydrogen peroxide (1 drop = 20 μL) were added to decompose the residual organic matter. The above decomposition process using sulfuric acid carbonation, nitric acid and hydrogen peroxide was repeated until the sample was clearly dissolved.

3) After adding 100 μL of scandium (Sc), an internal standard material, to the sample solution, it was diluted so that the total volume of the solution became 10 mL while adding ultrapure water (deionized water). If the measured concentration did not fall within the calibration curve, it was further diluted.

4) The standard solution was prepared as blank, 1 μg/mL, 5 μg/mL, and 10 μg/mL (addition of scandium (Sc), an internal standard material), and then the Pd content was analyzed by ICP-OES.

2. Organic solvent direct injection method (new method-Example according to the present invention)

2.1 ICP-OES plasma conditions

1) Plasma gas flow rate: 13L/min

2) Auxiliary gas flow rate: 0.2L/min

3) Nebulizer gas flow rate: 0.48L/min

4) RF power: 1400W

5) Pump flow rate: 1.3 mL/min

2.2 Pre-treatment method

1) Using an electrostatic gun, static electricity was removed from the centrifuge tube of 50 mL PP material and the Pd-containing sample. 5 mg of the sample was weighed and placed in the plastic centrifuge tube.

2) 100 μL of scandium (Sc), an internal standard material, was added to the sample, and then, while NMP was added, the total volume of the solution was diluted to a final 10 mL. It was further diluted 10 times with NMP so that the measured concentration falls within the calibration curve.

3) Standard solution was prepared at concentrations of blank, 1mg/L, 4mg/L and 10mg/L using NMP (addition of scandium (Sc), an internal standard material), and then introduced directly into ICP-OES to analyze Pd content. .

3. Comparison of results

-According to the NMP solvent-based pretreatment method (Example), the standard solution was diluted with an NMP solvent and the calibration curve was checked. As a result, the linearity of the ICP-OES intensity compared to the Pd concentration (mg/L) was confirmed. These results can be confirmed from the calibration curve shown in FIG.

-When comparing the shape of the Pd peak by ICP-OES, as shown in Fig. 2, there was no significant difference when comparing the NMP solvent-based measurement method with the conventional ultrapure water (deionized water)-based measurement method (Comparative Example). That is, it can be seen that the NMP solvent-based pretreatment method does not have chemical interference due to the carbon complex when measuring ICP-OES.

-The results of Pd catalyst analysis by the conventional ultrapure water (deionized water)-based measurement method (using nitric acid decomposition after sulfuric acid carbonization) and NMP solvent-based measurement method are shown in Table 1 below.

As can be seen in Table 1 above, the NMP solvent-based measurement method analyzes the Pd content of the Pd catalyst within the error range with a significantly shortened time compared to the conventional ultrapure water (deionized water)-based measurement method using nitric acid decomposition after sulfuric acid carbonation. can do.

Therefore, the NMP solvent-based measurement method can quantitatively analyze the Pd content of the Pd catalyst while significantly shortening the analysis time compared to the conventional ultrapure water (deionized water)-based measurement method using nitric acid decomposition after sulfuric acid carbonation.

From the above, it can be seen that the present invention is suitable for analyzing the catalyst content with similar accuracy within a shorter time than the conventional analysis.

In the above, preferred embodiments according to the present invention have been described with reference to the examples and drawings, but these are illustrative and those of ordinary skill in the art are not limited thereto, and various modifications and It will be appreciated that other equivalent embodiments are possible. Accordingly, it will be said that the substantial scope of the present invention is defined by the appended claims and their equivalents.

Claims (7)

Weighing a sample containing a Pd catalyst and introducing it into a plastic container;
Performing a pretreatment process of diluting the sample by adding an organic solvent to the sample; And
Incorporating a step of introducing a mixture of the sample obtained by the pretreatment and the organic solvent into an inductively coupled plasma optical emission spectrometry (ICP-OES),
The organic solvent is N-methylpyrrolidone (NMP), isopropyl alcohol (IPA), or a mixture thereof, a quantitative analysis method of a Pd catalyst. delete The method of claim 1, wherein the plastic container is a centrifuge tube made of polyethylene (PE), polypropylene (PP), polystyrene (PS) or perfluoroalkoxy (PFA). Analysis method. delete delete The method of claim 1, wherein the ratio of the catalyst-containing sample and the organic solvent is 1:1000 to 1:10000 by weight. The Pd catalyst according to claim 1, wherein an internal standard method with a known concentration in the catalyst-containing sample and the organic solvent is used to reduce an error in a measurement value due to a change in the amount of introduction of the sample or plasma change of ICP-OES. Quantitative analysis of.

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