Impurity acquisition method and impurity acquisition device for acquiring metal impurity in organic solvent

Abstract

According to the present invention, provided is an impurity acquisition method characterized by comprising: an adsorption / capture step in which an organic solvent is passed through an adsorbent and metal impurities in the organic solvent are adsorbed or captured by the adsorbent; a replacement step in which ultrapure water or a high-purity gas is caused to flow through the adsorbent, and the organic solvent remaining in the adsorbent is replaced with the ultrapure water or the high-purity gas; and an elution / recovery step in which an eluent is passed through the adsorbent, and the metal impurities adsorbed on the adsorbent are eluted and recovered.

Description

Technical Field

[0001] The present application is based on and claims the benefit of priority from Japanese patent application No. 2022-147868 filed on September 16, 2022, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to an impurity obtaining method and an impurity obtaining device for obtaining metal impurities in an organic solvent. Background Art

[0003] High-purity fluids are used in the manufacturing process of electronic components such as semiconductors. Organic solvents, which are one of the fluids used in the manufacturing process of electronic components, are also required to have high purity (high cleanliness).

[0004] Organic solvents contain more impurities than ultrapure water, but as electronic components become smaller, there is a demand for further reductions in impurities in organic solvents. Furthermore, as the required impurity levels become stricter, the requirements for analytical evaluation technology are also becoming stricter.

[0005] Japanese Patent Publication No. 2001-141721 and Japanese Patent Publication No. 2002-005799 disclose methods for analyzing samples by evaporation concentration (drying) using microwaves as analytical methods for organic solvents. Japanese Patent Publication No. 2009-288021 discloses a method for concentrating and analyzing a solution containing a chelating agent that can form a complex with the metal of the analytical object and using a filler that can capture the complex to concentrate the solution. Summary of the invention

[0006] However, the methods described in Japanese Patent Application Publication No. 2001-141721 and Japanese Patent Application Publication No. 2002-005799 are pre-treatments such as evaporation concentration for low-concentration analysis. However, the lower the concentration of impurities, the more organic solvents need to be recovered into the sampling bottle, and the higher the overall analysis cost. Furthermore, depending on the type of organic solvent, there are also issues such as evaporation operation, safety during bottle transportation, and environmental load caused by the occurrence of discharge.

[0007] Furthermore, when analyzing metal impurities in an organic solvent, the metal in the organic solvent is unstable or in the form of fine particles, so the metal adheres to the sampling bottle and causes deviations in the analysis value, making it impossible to perform accurate analysis.

[0008] In the method described in Japanese Patent Application Laid-Open No. 2009-288021, the metals to be analyzed are limited to those that can form a complex. Furthermore, further improvements are required to analyze low-concentration metal impurities contained in an organic solvent.

[0009] Therefore, an object of the present invention is to provide an impurity acquisition method and an impurity acquisition device capable of stably and safely acquiring low-concentration metal impurities in an organic solvent.

[0010] The present invention provides an impurity obtaining method for obtaining metal impurities in an organic solvent, characterized by comprising:

[0011] an adsorption / capturing step, wherein the organic solvent is passed through an adsorbent, and the adsorbent adsorbs or captures metal impurities in the organic solvent;

[0012] a replacement step, wherein ultrapure water or high-purity gas is passed through the adsorbent to replace the organic solvent remaining in the adsorbent with the ultrapure water or high-purity gas; and

[0013] The elution and recovery step comprises passing an eluent through the adsorbent to elute and recover the metal impurities adsorbed on the adsorbent.

[0014] The present invention also provides a method for analyzing metal impurities in an organic solvent, which comprises analyzing metal elements in an eluted / recovered liquid obtained by the above-mentioned impurity acquisition pre-analysis treatment method.

[0015] The present invention also provides an impurity obtaining device for obtaining metal impurities in an organic solvent, which comprises:

[0016] An adsorbent, through which the organic solvent passes, adsorbs or captures metal impurities in the organic solvent;

[0017] a fluid supply line that supplies ultrapure water or high-purity gas to the adsorbent to replace the organic solvent remaining in the adsorbent; and

[0018] The eluent supply line allows the eluent to pass through the adsorbent to elute and recover the metal impurities adsorbed on the adsorbent.

[0019] According to the present invention, it is possible to provide an impurity acquisition method and an impurity acquisition device capable of stably and safely acquiring low-concentration metal impurities in an organic solvent.

[0020] The above and other objects, features and advantages of the present application will become more apparent from the detailed description given below with reference to the accompanying drawings which illustrate the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a flow chart of one embodiment of the method for obtaining metal impurities in an organic solvent according to the present invention.

[0022] Figure 2 This is a flowchart of another embodiment of the method for obtaining metal impurities in an organic solvent according to the present invention. DETAILED DESCRIPTION

[0023] Hereinafter, an embodiment of the present invention will be described in detail. This embodiment is an example for carrying out the present invention, and the present invention is not limited to this embodiment.

[0024] The method for removing metal impurities from an organic solvent of the present invention comprises an adsorption and capture step, a substitution step, and an elution and recovery step.

[0025] The adsorption / capturing step is a step of passing an organic solvent through an adsorbent to adsorb or capture metal impurities in the organic solvent on the adsorbent.

[0026] Examples of the organic solvent to be analyzed include organic solvents used in semiconductor manufacturing processes, and specifically include isopropyl alcohol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, butyl butyrate, propylene glycol monopropyl ether, cyclohexanone, methyl methoxypropionate, butyl acetate, γ-butyrolactone, 4-methyl-2-pentanol, propylene glycol monoethyl ether, ethyl lactate, cyclopentanone, diisoamyl ether, isoamyl acetate, dimethyl sulfoxide, N-methyl 1-octanol, 2-octanol, 1-octanol, 2-octanol, ethyl acetoacetate, dimethyl pyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene glycol, ethylene carbonate, propylene carbonate, cyclopentanone, 2-heptanone, isobutyl isobutyrate, undecane, amyl propionate, isopentyl propionate, ethyl cyclohexane, mesitylene, decane, 3,7-dimethyl-3-octanol, 2-ethyl-1-hexanol, 1-octanol, 2-octanol, ethyl acetoacetate, dimethyl malonate, methyl pyruvate and dimethyl oxalate, etc.

[0027] The organic solvent preferably contains metal impurities of any one or two or more elements such as Li, B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Mo, Ag, Cd, Sn, Sb, Ba, W, Au, Pb or Pt, and these metal impurities exist in the form of ionic impurities, colloidal or monodispersed particles, or complexes.

[0028] The concentration of metal impurities in the organic solvent to be analyzed is not particularly limited. The impurity acquisition method of the present invention exerts particularly excellent effects when the concentration of metal impurities is low. Therefore, the concentration of metal impurities in the organic solvent to be analyzed is preferably 100 ng / L or less, more preferably 10 ng / L or less, and particularly preferably 1 ng / L or less. It should be noted that, when the organic solvent to be analyzed contains metal impurities of multiple elements, the concentration of metal impurities of at least one element may be within the above range, or the concentration of metal impurities of all elements may be within the above range.

[0029] The adsorbent that adsorbs or captures metal impurities in the organic solvent is not particularly limited, and examples thereof include materials having ion exchange groups such as monolithic organic porous ion exchangers, porous membranes, and ion exchange resins.

[0030] The monolithic organic porous ion exchanger is not particularly limited as long as it is an ion exchanger in which the framework is formed of an organic polymer and the ion exchange groups are introduced into a porous body having a plurality of communicating pores between the frameworks that serve as flow paths for the reaction solution. For example, the first monolithic ion exchanger described in paragraphs

[0019] to

[0028] of Japanese Patent Application Laid-Open No. 2010-234357 can be cited. Paragraphs

[0019] to

[0028] of Japanese Patent Application Laid-Open No. 2010-234357 are incorporated herein by reference.

[0031] The first integral ion exchanger is obtained by introducing ion exchange groups into the integral body, and the bubble-shaped macropores overlap each other. The overlapping parts form a continuous macroporous structure with openings (mesopores) with an average diameter of 30 to 300 μm, preferably 30 to 200 μm, and especially 35 to 150 μm in a water-wet state.

[0032] The first integral ion exchanger is obtained by performing the following steps as described in paragraphs

[0029] to

[0051] of Japanese Patent Application Laid-Open No. 2010-234357: Step I, preparing a water-in-oil emulsion by stirring a mixture of an oil-soluble monomer not containing ion exchange groups, a surfactant and water, and then polymerizing the water-in-oil emulsion to obtain a monolithic organic porous intermediate having a continuous macroporous structure with a total pore volume of 5 to 16 ml / g; Step II, preparing a mixture comprising a vinyl monomer, a cross-linking agent having at least two vinyl groups in one molecule, an organic solvent that dissolves the vinyl monomer or the cross-linking agent but does not dissolve a polymer generated by polymerization of the vinyl monomer, and a polymerization initiator; Step III, polymerizing the mixture obtained in Step II while standing and in the presence of the monolithic organic porous intermediate obtained in Step I to obtain a coarse skeleton organic porous body having a skeleton coarser than that of the organic porous intermediate; and Step IV, introducing ion exchange groups into the coarse skeleton organic porous body obtained in Step III. Paragraphs

[0029] to

[0051] of Japanese Patent Application Laid-Open No. 2010-234357 are incorporated herein by reference.

[0033] In addition, as a monolithic organic porous ion exchanger, there can be mentioned the second monolithic ion exchanger described in paragraphs

[0052] to

[0061] of JP-A-2010-234357.

[0034] The second integral ion exchanger is a co-continuous structure including a three-dimensional continuous skeleton and a three-dimensional continuous cavity, wherein the three-dimensional continuous skeleton contains an aromatic vinyl polymer containing 0.3 to 5.0 mol% of cross-linked structural units in all structural units of the introduced ion exchange groups, and the diameter of the three-dimensional continuous cavities between the skeletons is 10 to 100 μm, and the total pore volume is 0.5 to 5 ml / g, the ion exchange capacity per unit volume in a water-wet state is 0.3 to 5 mg equivalent / ml, and the ion exchange groups are uniformly distributed in the porous ion exchanger. Paragraphs

[0052] to

[0061] of Japanese Patent Application Laid-Open No. 2010-234357 are incorporated herein by reference.

[0035] The second integral ion exchanger is obtained by performing the following steps as described in paragraphs

[0062] to

[0083] of Japanese Patent Application Laid-Open No. 2010-234357: Step I, preparing a water-in-oil emulsion by stirring a mixture of an oil-soluble monomer not containing ion exchange groups, a surfactant and water, and then polymerizing the water-in-oil emulsion to obtain an integral organic porous intermediate having a continuous macroporous structure with a total pore volume exceeding 16 ml / g and not more than 30 ml / g; Step II, preparing a mixture of an aromatic vinyl monomer, 0.3 to 5 mol % of a crosslinking agent in a fully oil-soluble monomer having at least two vinyl groups in one molecule, an organic solvent that dissolves the aromatic vinyl monomer or the crosslinking agent but does not dissolve the polymer generated by polymerization of the aromatic vinyl monomer, and a polymerization initiator; Step III, polymerizing the mixture obtained in Step II while standing and in the presence of the integral organic porous intermediate obtained in Step I to obtain a co-continuous structure; and Step IV, introducing ion exchange groups into the co-continuous structure obtained in Step III. Paragraphs

[0062] to

[0083] of Japanese Patent Application Laid-Open No. 2010-234357 are incorporated herein by reference.

[0036] The resin (gel type) is synthesized by copolymerizing styrene and divinylbenzene in the presence of a catalyst and a dispersant, and then introducing a functional group. The copolymer has a three-dimensional crosslinked structure, and the matrix has pores (mesopores).

[0037] The resin (MR type) is synthesized by adding an organic solvent to copolymerize styrene and divinylbenzene to polymerize them and then introducing functional groups. The copolymer has a giant network structure, and the matrix has not only pores (mesopores) but also spaces formed by aggregation of small granular gel particles (macroporos).

[0038] Among these adsorbents, monolithic organic porous ion exchangers are preferably used for the following reasons.

[0039] Compared with other adsorbents, the adsorbed or captured metal impurities are easily eluted by the eluent, and the amount of the eluent used can be reduced, thereby reducing the amount of the organic solvent to be analyzed that passes through the adsorbent.

[0040] Since the passing speed of the organic solvent to be analyzed can be increased, a large amount of the organic solvent can be passed in a short time, and the time required for the adsorption and capture step can be greatly shortened.

[0041] The eluted and recovered liquid obtained by using the monolithic organic porous ion exchanger as the adsorbent is in an acid-added state, and metals do not adhere to bottles and the like, so the storage (preservation) is excellent.

[0042] In the adsorption and capture step, the amount of the organic solvent to be analyzed that passes through the adsorbent is appropriately selected according to the content of metal impurities in the organic solvent to be analyzed, the type or thickness of the adsorbent, the passing speed, etc. It should be noted that when calculating the content of each metal impurity in the organic solvent to be analyzed from the content of each metal impurity in the eluent (recovery liquid) obtained in the analysis step, the total amount of the organic solvent to be analyzed that passes through the adsorbent is required. Therefore, in the adsorption and capture step, the total amount of the organic solvent to be analyzed that passes through the adsorbent is measured.

[0043] In the adsorption and capture step, the conditions for passing the organic solvent to be analyzed through the adsorbent are not particularly limited. Regarding the passing speed, the SV (space velocity) is preferably 2000 h -1 Below, more preferably 1000h -1 Below, particularly preferably 200h -1 In addition, the LV (linear velocity) is preferably 1000 m / h or less, and particularly preferably 500 m / h or less. In addition, the liquid flow time is appropriately selected according to the total flow rate and flow rate of the organic solvent to be analyzed.

[0044] Then, in the adsorption / capturing step, ionic impurities, colloid or monodisperse particles, or metal impurities in a complex state in the organic solvent to be analyzed are captured by the adsorbent.

[0045] The replacement step is a step of replacing the organic solvent remaining in the flow cell storing the adsorbent, particularly in the adsorbent, after the organic solvent to be analyzed is passed in the adsorption / capturing step.

[0046] Specifically, it is a process of passing ultrapure water or high-purity gas through the adsorbent to replace the organic solvent remaining in the adsorbent with ultrapure water or inert gas.

[0047] In addition, when the adsorbent is a whole, the spaces (macroporous holes) of the whole mesh structure in the adsorbent, the pores (mesopores) of the three-dimensional cross-linked structure of the matrix, and the like are considered.

[0048] When the adsorbent is a resin (gel type), it is considered that the adsorbent contains pores (mesopores) or the like of a three-dimensional cross-linked structure of the matrix.

[0049] In the case of a resin (MR type), the adsorbent is considered to contain spaces (macroporous) of gel microsphere aggregates, pores (mesopores) of a three-dimensional cross-linked structure of the matrix, and the like.

[0050] Ultrapure water refers to water having a resistivity of 2 MΩ·cm or more. The lower the concentration of metal impurities in ultrapure water, the better. The concentration of metal impurities is less than 1 ng / L, more preferably less than 0.1 ng / L, and particularly preferably less than 0.05 ng / L.

[0051] As the high-purity gas, a gas with a purity of 99.9% or more is preferred, and a gas with a purity of 99.99% or more is particularly preferred. The less impurities in the gas, the more preferred. As the type of gas, inert gas, air (atmosphere) or oxygen can be mentioned. As the inert gas, rare gases such as nitrogen, argon and helium can be mentioned. The impurities contained in the high-purity gas are methane, oxygen, carbon dioxide, water, etc. in the case of an inert gas, and particles, moisture, etc. in the case of air and oxygen.

[0052] When ultrapure water is used in the replacement step, the amount of ultrapure water passing through the adsorbent is appropriately selected according to the type or thickness of the adsorbent, the passing speed, etc. In addition, there is no particular restriction on the passing conditions when ultrapure water is passed through the adsorbent. Regarding the passing speed, SV is preferably 20000h -1 Below, more preferably 10h -1 Above and 4000h -1 In addition, LV is preferably 1000 m / h or less, and particularly preferably 1 m / h or more and 80 m / h or less. In addition, the passage time is appropriately selected according to the total amount of ultrapure water passing through and the passage speed.

[0053] In the replacement process, when a high-purity gas is used, the amount of high-purity gas supplied to the adsorbent is appropriately selected according to the type or thickness of the adsorbent, the supply rate, etc. There is no particular restriction on the supply conditions when supplying the high-purity gas to the adsorbent, and the supply rate is preferably SV 10000h -1 Below, particularly preferably 5000h -1 In addition, the supply time is appropriately selected according to the total supply amount and supply speed of the high-purity gas.

[0054] In the replacement process, the direction in which the ultrapure water and the high-purity gas flow is preferably the same as the direction in which the organic solvent flows in the adsorption and capture process. By setting such a direction, even if impurities adsorbed on the adsorbent are detached when the ultrapure water or the high-purity gas flows, they can be adsorbed on the adsorbent again on the downstream side.

[0055] By the substitution treatment in the substitution step, the organic solvent remaining in the adsorbent is replaced with ultrapure water and an inert gas, and no organic solvent remains in the adsorbent. Therefore, in the elution and recovery step, even if an aqueous solution containing an acid is passed through the adsorbent as an eluent, the organic solvent reactive with the acid does not come into contact with the acid, thereby maintaining safety.

[0056] The elution and recovery process is a process of passing the elution liquid into the adsorbent that has been replaced with the organic solvent in the replacement process and has adsorbed and captured the metal impurities, thereby obtaining the discharge liquid discharged from the adsorbent, that is, the recovery liquid obtained by eluting the metal impurities adsorbed and captured by the adsorbent.

[0057] The eluent is an aqueous solution containing an acid. The acid contained in the eluent is not particularly limited, and examples thereof include inorganic acids such as nitric acid, sulfuric acid, hydrochloric acid, and phosphoric acid, and organic acids such as methanesulfonic acid. Among them, as the acid contained in the eluent, nitric acid, sulfuric acid, and hydrochloric acid are preferred because they are easy to elute ionic impurity elements from the adsorbent and require a high-purity reagent.

[0058] The acid concentration in the eluent is not particularly limited, but is preferably 0.1 N or more and 3.0 N or less. In addition, as the eluent, an eluent having a concentration of each metal impurity of 100 ng / L or less is preferred, nitric acid or hydrochloric acid having a content of each metal impurity of 10 ng / L or less is more preferred, and nitric acid or hydrochloric acid having a content of each metal impurity of 1 ng / L or less is particularly preferred.

[0059] The direction in which the eluent passes in the elution step is preferably opposite to (in the opposite direction to) the direction in which the organic solvent passes in the adsorption / capturing step.

[0060] Since the amount of impurities in the organic solvent passing through the adsorbent in the adsorption / capturing step decreases with the direction of passage, a high recovery rate can be obtained using a smaller amount of eluent by passing the eluent in such a direction in the concentration step.

[0061] In the elution and recovery step, the metal impurities in the organic solvent to be analyzed that are adsorbed and captured by the adsorbent are eluted by the eluent and transferred to the eluent to obtain an eluent (recovery liquid) containing the metal impurities that are adsorbed and captured by the adsorbent.

[0062] The impurity analysis method of the present invention performs analysis of metal elements in an eluate (recovery liquid) containing metal impurities obtained in the elution and recovery step in the impurity acquisition method of the present invention.

[0063] There are no particular limitations on the method for measuring the content of each metal impurity in the eluted and recovered liquid, and examples include a method using an ICP-MS device, an ICP emission spectrometer (ICP), an atomic absorption photometer, an ion chromatograph, etc. The measurement conditions can be appropriately selected.

[0064] In the analysis method of the present invention, the content of each metal impurity in the organic solvent as the analysis object is calculated based on the content of each metal impurity in the elution / recovery liquid obtained by analysis, the recovery amount of the elution / recovery liquid and the total amount of the organic solvent as the analysis object passing through the ion adsorbent in the adsorption / capture process.

[0065] Next, an example of an embodiment of the method for obtaining and analyzing metal impurities in an organic solvent according to the present invention will be described.

[0066] For example, Figure 1 As shown, it has the following structure: in an organic solvent supply pipeline 13 that supplies an organic solvent 20 to an organic solvent supply destination 12 such as a usage point or an organic solvent storage tank, a branch pipeline 14 is connected in the middle, a metal impurity acquisition kit 16 having a flow chamber 17 with an adsorbent, preferably an integral organic porous ion exchanger, and a cumulative flowmeter 18 is installed on the branch pipeline 14, and a refining component 19 for refining the organic solvent is preferably installed at the rear section of the metal impurity acquisition kit 16, and a return pipeline 15 that returns the organic solvent 20 that has passed through the metal impurity acquisition kit 16 (the refining component 19 when the refining component 19 is provided) to the organic solvent supply pipeline 13 is connected to the rear section of the metal impurity acquisition kit 16 (the refining component 19 when the refining component 19 is provided), and the other end side of the return pipeline 15 is connected to the downstream side relative to the portion of the organic solvent supply pipeline 13 connected with the branch pipeline 14.

[0067] Then, the organic solvent 20 to be analyzed is supplied to the flow cell 17 via the organic solvent supply line 13 and the branch line 14, and the organic solvent 20 is passed through the monolithic organic porous ion exchanger to perform the adsorption and capture process of impurities. At this time, the total amount of the organic solvent 20 passing through the flow cell 17 (monolithic organic porous ion exchanger) is measured by the cumulative flow meter 18. The organic solvent that has passed through the metal impurity acquisition kit 16 is returned to the organic solvent supply line 13 via the return line 15. The return of the organic solvent 20 that has passed through the metal impurity acquisition kit 16 can be performed by a pump (not shown) provided inside or outside the metal impurity acquisition kit 16. Next, after a given amount of the organic solvent 20 has passed, the metal impurity acquisition kit 16 is removed from the branch line 14. At this time, the removal is performed in a manner that does not cause contamination from the outside to the inside of the metal impurity acquisition kit 16, and the inside is sealed. Next, a replacement process is performed, wherein the metal impurity acquisition kit 16 is installed in a replacement device provided at a location different from the organic solvent supply line 13, and ultrapure water or inert gas or both are supplied from the supply portion of the replacement device to the flow cell 17 of the metal impurity acquisition kit 16 in the same direction as the passing direction of the organic solvent in the adsorption and capture process, thereby replacing the organic solvent 20 remaining in the flow cell 17, especially in the monolithic organic porous ion exchanger. Next, the metal impurity acquisition kit 16 is installed in an elution and recovery device, and the eluent is passed through the monolithic organic porous ion exchanger in the flow cell 16 from the elution and recovery liquid supply pipe of the elution and recovery device to the flow cell 17 of the metal impurity acquisition kit 16 in the direction opposite to the passing direction of the organic solvent in the adsorption and capture process (opposite direction), and the elution and recovery liquid from the metal impurity acquisition kit 16 is recovered, and the elution and recovery process is performed. Next, the content of metal impurities in the elution and recovery liquid is measured, and an analysis process is performed. Then, the content of each metal impurity in the organic solvent 20 is obtained from the above results.

[0068] It should be noted that, in the present embodiment, the configuration in which the pre-analysis treatment kit 16 includes a flow chamber 17 having an integral organic porous ion exchanger and an integrating flow meter 18 is described, but the configuration may also be as follows: the metal impurity acquisition kit 16 includes a flow chamber 17 having an integral organic porous ion exchanger, and the integrating flow meter 18 is disposed outside (at the rear end) of the pre-analysis treatment kit 16.

[0069] When the metal impurity acquisition kit 16 is removed from the branch line 14 , the flow cell 17 including the monolithic organic porous ion exchanger may be removed from the branch line 14 and the integrating flow meter 18 may be attached to the branch line 14 .

[0070] As another example, Figure 2 Example shown.

[0071] like Figure 2 As shown, the organic solvent supply line 13 may be provided with an organic solvent refining device 11 in the middle thereof.

[0072] exist Figure 2 In the organic solvent supply line 13 shown in FIG. 1 , the raw material drug solution 10 is supplied to the organic solvent refining device 11, and the organic solvent 20 obtained by the organic solvent refining device 11 is supplied to the organic solvent supply destination 12. In addition, a branch line 14 is connected to the downstream side of the organic solvent refining device 11 in the middle of the organic solvent supply line 13, and a metal impurity acquisition kit 16 is installed on the branch line 14. The metal impurity acquisition kit 16 is connected to the organic solvent refining device 11. Figure 1 The metal impurity acquisition reagent kit 16 described in the above is similarly constructed. A return line for returning the organic solvent 20 that has passed through the metal impurity acquisition reagent kit 16 is connected to the rear section of the metal impurity acquisition reagent kit 16. The return line can connect the other end of the return line 15 to the downstream side of the portion of the organic solvent supply line 13 to which the branch line 14 is connected, and return the organic solvent to the organic solvent supply line 13 (return line 15A), or return it to the upstream side of the organic solvent refining device 11 (return line 15B).

[0073] For other aspects, direct application Figure 1 Instructions in .

[0074] Figure 2 The organic solvent refining device 11 shown may be any device that can purify the organic solvent 20 that has passed through the metal impurity obtaining kit 16 to satisfy the standard value of liquid quality for use in electronic component manufacturing, and examples thereof include ion exchange resins and particle removal membranes.

[0075] The impurity acquisition method of the present invention and the impurity analysis method of the present invention, including the adsorption / capture step, the replacement step and the elution step, may all be performed at the site where the organic solvent to be analyzed is produced. The replacement step, the elution step and the impurity analysis method of the present invention may be performed at a site (device) different from the adsorption / capture step in the impurity acquisition method of the present invention. The adsorption / capture step, the replacement step and the elution step in the impurity acquisition method of the present invention may be performed at the same site (device) and the impurity analysis method of the present invention may be performed at a site (device) different from the site (device) where they are performed. The adsorption / capture step, the replacement step, the elution step and the impurity analysis method of the present invention may be performed at different sites (devices) respectively.

[0076] Next, regarding the impurity acquisition device of the present invention, Figure 1 The illustrated embodiment will be described.

[0077] like Figure 1 As shown, the impurity acquisition device for metal impurities in an organic solvent of the present invention comprises: a metal impurity acquisition reagent box 16; and a return pipeline 15, which returns the organic solvent that has passed through the cumulative flow meter 18 to the organic solvent supply pipeline 13, wherein the metal impurity acquisition reagent box 16 has a flow chamber 17 and a cumulative flow meter 18, the flow chamber 17 is connected to a branch pipeline 14 branched from an organic solvent supply pipeline 13 for supplying the organic solvent as an analysis object to a supply destination 12, and is equipped with an adsorbent for passing the organic solvent as an analysis object through the adsorbent, and the cumulative flow meter 18 is used to measure the amount of the organic solvent as an analysis object that has passed through the flow chamber 17.

[0078] The impurity acquisition device may be provided with a pump inside or outside the metal impurity acquisition reagent box 16 as a means for returning the organic solvent that has passed through the metal impurity acquisition reagent box 16 .

[0079] The metal impurity acquisition kit 16 of the impurity acquisition device is connected to the organic solvent supply pipeline 13 via a branch pipeline 14 and a return pipeline 15. The organic solvent as the analysis object is transported to the metal impurity acquisition kit 16 via the branch pipeline 14, and after passing through the metal impurity acquisition kit 16, it is returned to the organic solvent supply pipeline 13 via the return pipeline 15.

[0080] As described above, in the impurity acquisition device 16 of the present invention, the organic solvent to be analyzed is returned to the organic solvent supply line 13 and the waste liquid is reused, so the generation of the waste liquid is reduced.

[0081] As described above, the metal impurity acquisition kit 16 includes the flow cell 17 having an adsorbent and the integrating flow meter 18 .

[0082] The flow cell 17 including the ion adsorbent may be any container provided with an inlet and an outlet for passing a liquid and capable of accommodating the ion adsorbent, and may be made of resin or metal.

[0083] The adsorbent included in the flow cell is the adsorbent described in the adsorption and capture step in the method for obtaining metal impurities in an organic solvent of the present invention, and a monolithic organic porous ion exchanger can be preferably used.

[0084] The integrating flow meter is not particularly limited as long as it can measure and integrate the amount of the introduced liquid.

[0085] A purification unit 19 may be preferably provided at the rear stage of the metal impurity acquisition reagent 16. The purification unit 19 is usually provided at the rear stage (outside) of the metal impurity acquisition reagent 16, but may also be provided inside the metal impurity acquisition reagent 16.

[0086] The refining component 19 plays a role in adsorbing and capturing particles other than metal impurities contained in the organic solvent to quiescently control the organic solvent passing through the flow chamber. As the refining component 19, there is no particular limitation as long as it is a component used for refining the organic solvent, and examples thereof include ion exchangers, microfiltration membranes (MF), ultrafiltration membranes (UF), etc. These components may also be used separately. In addition, these components may also be used in any combination.

[0087] The metal impurity acquisition reagent kit 16 may also include: a supply pipe for supplying an organic solvent to be analyzed to the adsorbent in the flow chamber; a supply pipe 21 for supplying ultrapure water for replacement or a supply pipe 22 for supplying a high-purity gas; a supply pipe for supplying an elution / recovery liquid; and a discharge pipe 23 for discharging a discharge liquid discharged from the adsorbent or a discharge pipe 24 for discharging a discharge gas. The discharge port of the integrating flow meter may be used as a discharge pipe for discharging the discharge liquid or the discharge gas to the outside of the metal impurity acquisition reagent kit 16.

[0088] The metal impurity obtaining reagent kit 16 is provided with a sealing unit for sealing the inside so that contamination of the inside of the metal impurity obtaining reagent kit 16 is not caused after the metal impurity obtaining reagent kit 16 is removed from the tube to which the organic solvent to be analyzed is supplied.

[0089] Example

[0090] Next, the present invention will be specifically described with reference to Examples. However, these are merely illustrative and are not intended to limit the present invention.

[0091] The second cationic monolithic ion exchanger was prepared by the same method as Reference Example 17 described in the Examples of the specification of Japanese Patent Application Laid-Open No. 2010-234357. Specifically, the second cationic monolithic ion exchanger was prepared by the method described below. Reference Example 17 described in the Examples of Japanese Patent Application Laid-Open No. 2010-234357 is incorporated herein by reference.

[0092] <Manufacturing of Cationic Monolithic Ion Exchanger>

[0093] (Step I: Production of the overall intermediate)

[0094] 5.4 g of styrene, 0.17 g of divinylbenzene, 1.4 g of sorbitan monooleate (hereinafter referred to as SMO) and 0.26 g of 2,2'-azobis(isobutyronitrile) were mixed and dissolved uniformly. Next, the styrene / divinylbenzene / SMO / 2,2'-azobis(isobutyronitrile) mixture was added to 180 g of pure water, and a vacuum stirring and degassing mixer (manufactured by EME) as a planetary stirring device was used to stir under reduced pressure in a temperature range of 5°C to 20°C to obtain an oil-in-water emulsion. The emulsion was quickly transferred to a reaction container, sealed and allowed to stand for polymerization at 60°C for 24 hours. After the polymerization was completed, the contents were taken out, extracted with methanol, and then dried under reduced pressure to produce an integral intermediate with a continuous macroporous structure. The internal structure of the overall intermediate (dried body) thus obtained was observed by SEM images. As a result, although the wall dividing two adjacent macropores was extremely thin and rod-shaped, it had a continuous bubble structure. The average diameter of the openings (mesopores) of the overlapping parts of the macropores measured by mercury penetration was 70 μm, and the total pore volume was 21.0 ml / g.

[0095] (Manufacturing of co-continuous structures as a whole)

[0096] Next, 76.0 g of styrene, 4.0 g of divinylbenzene, 120 g of 1-decanol, and 0.8 g of 2,2'-azobis(2,4-dimethylvaleronitrile) were mixed and uniformly dissolved (step II). Then, the above-mentioned overall intermediate was cut into a disc with a diameter of 70 mm and a thickness of about 40 mm, and 4.1 g was taken out. The separated overall intermediate was placed in a reaction vessel with an inner diameter of 110 mm, immersed in the styrene / divinylbenzene / 1-decanol / 2,2'-azobis(2,4-dimethylvaleronitrile) mixture, and after degassing in a reduced pressure chamber, the reaction vessel was sealed and polymerized at 60°C for 24 hours while standing. After the polymerization was completed, the overall content with a thickness of about 60 mm was taken out, Soxhlet extraction was performed with acetone, and then reduced pressure drying was performed at 85°C overnight (step III).

[0097] The internal structure of the whole (dried body) containing 3.2 mol% of the cross-linked component of the styrene / divinylbenzene copolymer thus obtained was observed by SEM, and the result was that the whole was a co-continuous structure in which the skeleton and the pores were three-dimensionally continuous and the two phases were intertwined. In addition, the thickness of the skeleton measured by the SEM image was 17 μm. In addition, the size of the three-dimensional continuous pores of the whole measured by mercury penetration was 41 μm, and the total pore volume was 2.9 ml / g.

[0098] (Manufacturing of a co-continuous cationic monolithic ion exchanger (CEM))

[0099] The whole manufactured by the above method is cut into a cylindrical shape with a diameter of 75 mm and a thickness of about 15 mm. The weight of the whole is 18 g. 1500 ml of dichloromethane is added thereto, heated at 35°C for 1 hour, cooled to below 10°C, 99 g of chlorosulfuric acid is slowly added, the temperature is raised, and the reaction is carried out at 35°C for 24 hours. Then, methanol is added to quench the residual chlorosulfuric acid, washed with methanol to remove dichloromethane, and further washed with pure water to obtain a cationic integral ion exchanger (CEM) with a co-continuous structure.

[0100] (Manufacturing of anionic monolithic ion exchangers)

[0101] The CEM produced by the above method is cut into a disc with an outer diameter of 70 mm and a thickness of about 15 mm. 1400 ml of dimethoxymethane and 20 ml of tin tetrachloride are added thereto, and 560 ml of chlorosulfuric acid is added dropwise under ice cooling. After the addition is completed, the temperature is raised and the reaction is carried out at 35°C for 5 hours to introduce chloromethyl groups. After the reaction is completed, the mother liquor is extracted with a siphon, washed with a mixed solvent of THF / water = 2 / 1, and further washed with THF. 1000 ml of THF and 600 ml of a 30% aqueous solution of trimethylamine are added to the chloromethylated monolithic organic porous body, and the reaction is carried out at 60°C for 6 hours. After the reaction is completed, the product is washed with a methanol / water mixed solvent, and then washed and separated with pure water to obtain an anionic monolithic ion exchanger (AEM).

[0102] Reference Example 1 Bottle Storage Test

[0103] A simulated liquid was prepared in such a way that the concentration of each metal in an organic solvent (IPA) was about 200 ng / L, and stored in a 100 ml PFA bottle. The concentration of each metal impurity in the bottle after the first day (original solution) (0day), 3 days (3days), 6 days (6days), 10 days (10days), and 17 days (17days) of storage was measured using ICP-MS for organic solvents (manufactured by Agilent Technologies, Inc.) to evaluate the effect of the adsorption of each metal to the bottle.

[0104] The evaluation was performed by implementing (1) the simulated solution and (2) the eluate (recovered stock solution) obtained by the following steps. As the evaluation results, the change rate (%) of the concentration on each day from the first day of storage to 17 days after storage relative to the first day of storage (0 day) is shown in Table 1.

[0105] (Eluent (recovery stock solution))

[0106] The CEM prepared in Preparation Example 1 was cut into a shape of 10 mm in diameter x 50 mm in height and filled into a PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) filling container. Next, 100 ml of the simulated liquid was added at SV = 200 h.-1 Then, 100 ml of 2N nitric acid was added to the container filled with CEM at SV = 200 h -1 It was passed into a container filled with CEM and recovered into a PFA bottle as the eluent (recovered stock solution).

[0107] [Table 1]

[0108]

[0109] From the above results, it was confirmed that in the analysis of metal impurities in an organic solvent, since the metal impurities in the organic solvent were adsorbed on the ion adsorbent and then recovered in the bottle, the analysis values ​​of the metal impurities did not vary and were stable.

[0110] Example 1

[0111] (Adsorption and capture process)

[0112] The CEM or AEM prepared in Preparation Example 1 was cut into a shape of 10 mm in diameter and 50 mm in height and filled into a PFA filling container. Then, 100 ml of the simulated liquid was added at SV = 200 h so that the concentration of each metal in the organic solvent (IPA) was about 200 ng / L. -1 Pass through each container filled with CEM or AEM.

[0113] (Replacement process)

[0114] For each container filled with CEM or AEM after passing through, IPA in the container was replaced by the following two methods.

[0115] Method A (hereinafter referred to as "A" in Table 2)

[0116] Ultrapure water was passed into the container at 100 ml / min in the same direction as the simulated liquid for 30 seconds to replace the IPA in the container. 2 Purge at 100 ml / min for 1 minute.

[0117] Method B (hereinafter referred to as "B" in Table 2)

[0118] N 2 Purge at 100 ml / min in the same direction as the simulated liquid for 1 minute to replace the IPA in the container.

[0119] (Elution, recovery and analysis process)

[0120] 100 ml of 2N nitric acid is directed in the opposite direction to the simulated liquid or N2 at SV = 100 h -1 Pass into the container and recover into the PFA bottle.

[0121] The recovered stock solution was analyzed by ICP-MS (8900, manufactured by Agilent Technologies).

[0122] [Table 2]

[0123]

[0124] The above results confirmed that the recovery rate of metal impurities was improved when method A was used as the replacement step. In addition, it was confirmed that the use of AEM as a whole enabled analysis of metal impurities that could not be recovered by CEM.

[0125] Although certain preferred embodiments of the present invention have been shown and described in detail, it should be understood that various changes and modifications may be made without departing from the spirit or scope of the claims.

[0126] Description of Reference Numerals

[0127] 10 Raw water

[0128] 11Organic solvent refining device

[0129] 12Organic solvent supply destination

[0130] 13Organic solvent supply pipeline

[0131] 14 branch pipeline

[0132] 15, 15A, 15B return pipeline

[0133] 16 Metal impurities acquisition kit

[0134] 17 Flow Chamber

[0135] 18 Accumulated flow meter

[0136] 19Refined Parts

[0137] 20Organic solvents

[0138] 21 High purity gas supply pipe

[0139] 22 Ultrapure water supply pipe

[0140] 23 Gas exhaust pipe

[0141] 24 discharge liquid discharge pipe.

Claims

1. A method for obtaining metal impurities in an organic solvent, characterized in that: include: an adsorption / capturing step, wherein the organic solvent is passed through an adsorbent, and the adsorbent adsorbs or captures metal impurities in the organic solvent; a replacement step, wherein ultrapure water or high-purity gas is passed through the adsorbent to replace the organic solvent remaining in the adsorbent with the ultrapure water or high-purity gas; and The elution and recovery step comprises passing an eluent through the adsorbent to elute and recover the metal impurities adsorbed on the adsorbent.

2. The impurity obtaining method according to claim 1, wherein: The direction in which the ultrapure water or high-purity gas flows in the replacement step is the same as the direction in which the organic solvent flows in the adsorption / capture step; and / or The direction in which the eluent passes in the elution step is opposite to the direction in which the organic solvent passes in the adsorption / capturing step, that is, in the opposite direction.

3. The impurity obtaining method according to claim 1 or 2, wherein: The organic solvent passing through the adsorbent is obtained by fractionating at least a portion of the organic solvent flowing through an organic solvent supply line for supplying the organic solvent from an organic solvent supply source to an organic solvent supply destination.

4. The impurity obtaining method according to claim 3, wherein: The organic solvent having passed through the adsorbent is purified by passing through a purification unit for purifying the organic solvent, and the organic solvent purified by the purification unit is returned to the organic solvent supply line.

5. The impurity obtaining method according to claim 1 or 2, wherein: The organic solvent is at least one selected from isopropanol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, butyl butyrate, propylene glycol monopropyl ether, cyclohexanone, methyl methoxypropionate, butyl acetate, γ-butyrolactone, 4-methyl-2-pentanol, propylene glycol monoethyl ether, ethyl lactate, cyclopentanone, diisoamyl ether, isoamyl acetate, dimethyl sulfoxide, N-methylpyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene glycol, ethylene carbonate, propylene carbonate, cyclopentane, cycloheptanone, 2-heptanone, isobutyl isobutyrate, undecane, amyl propionate, isoamyl propionate, ethylcyclohexane, mesitylene, decane, 3,7-dimethyl-3-octanol, 2-ethyl-1-hexanol, 1-octanol, 2-octanol, ethyl acetoacetate, dimethyl malonate, methyl pyruvate and dimethyl oxalate.

6. The method for analyzing metal impurities in an organic solvent according to claim 5, wherein: The concentration of at least any one metal element of the metal impurities in the organic solvent is 10 ng / L or less.

7. The impurity obtaining method according to claim 1 or 2, wherein: The adsorbent is a monolithic organic porous ion exchanger.

8. An impurity obtaining device for obtaining metal impurities in an organic solvent, characterized in that: have: An adsorbent, through which the organic solvent passes, adsorbs or captures metal impurities in the organic solvent; a fluid supply line that supplies ultrapure water or high-purity gas to the adsorbent to replace the organic solvent remaining in the adsorbent; and The eluent supply line allows the eluent to pass through the adsorbent to elute and recover the metal impurities adsorbed on the adsorbent.

9. The impurity obtaining device according to claim 8, wherein: The impurity obtaining device is connected to a branch line branched from an organic solvent supply line for supplying the organic solvent from an organic solvent supply source to a supply destination.

10. The impurity obtaining device according to claim 9, wherein: The impurity obtaining device comprises: a purification unit for purifying the organic solvent after passing through the adsorbent; and A return line returns the organic solvent purified by the purification unit to the organic solvent supply line.

Images