WO2012033240A1

WO2012033240A1 - Method for purifying organic solvents

Info

Publication number: WO2012033240A1
Application number: PCT/KR2010/006100
Authority: WO
Inventors: 정현철; 문재웅; 정진배; 배은형; 강도순; 이명호
Original assignee: 주식회사 이엔에프테크놀로지
Priority date: 2010-09-08
Filing date: 2010-09-08
Publication date: 2012-03-15
Also published as: CN103080067B; CN103080067A; JP2013539472A; JP5637470B2

Abstract

The present invention relates to a method for purifying waste organic solvents. An alkoxide-based compound is added to waste organic solvents containing propylene glycol monomethylether acetate produced in a display manufacturing process and the like and the obtained mixture is reacted, thereby recovering purified products of a high purity in a high yield through the change in the boiling points of impurities such as propionates and ketones.

Description

Method for Purifying Organic Solvents Field of the Invention The present invention relates to a method for recovering propylene glycol monomethyl ether acetate in high yield by purifying waste organic solvents generated in the display manufacturing process. Background Art Lithography is widely used to manufacture electronic circuits, pixels, and the like in the manufacturing process of displays such as semiconductors and TFT-LCDs. This lithography is a method used to create a fine pattern on a substrate, and irradiates light through a mask on which a desired pattern is printed on a substrate on which a photoresist, a photosensitive material, is applied, to convert a circuit pattern of a mask into a substrate. The photoresist generally refers to a process of transferring, and the photoresist is generally composed of a binder component resins, photoinitiators, organic solvents, various pigments, dispersants, and other additives.

In the lithography process using photoresist, photoresist is deposited on unwanted portions, such as photoresist application nozzles, photocoating peripherals, or edges of the substrate in the photoresist application process. This may cause defects in the photoresist application process, which must be removed. At this time, an organic solvent is used to remove unwanted photoresist. Therefore, the waste organic solvent from which the photoresist is removed includes components of the photoresist, that is, resins, photoinitiators, pigments, organic solvents, and additives as impurities.

Waste organic solvents contaminated with impurities may be incinerated. Since the incineration process not only generates harmful chemicals but also reduces the useful value of the waste organic solvent itself, recently, a process of regenerating the waste organic solvent with a high-purity organic solvent is performed so that it can be reused in the display manufacturing process. Regeneration of such waste organic solvents is usually carried out using fractional distillation using the difference in boiling point for each component, similar to the general method for purifying organic solvents. However, many other organic solvent impurities contained in the waste organic solvent have similar boiling points to the organic solvent to be recovered. Such similar boiling point impurities are not easy to be separated by distillation by organic solvent components and distillation, and thus require a very high number of distillation columns, low productivity, high loss of organic solvents to be recovered, and high purity.

In order to obtain high purity PGMEA by purifying waste organic solvent of propylene glycol monomethyl ether acetate (hereinafter abbreviated as 'PGMEA'), which is widely used as an organic solvent in display manufacturing process, waste organic solvent Various solids and organic solvents such as alcohols, esters and ketones should be removed. However, among these, methyl 3-methoxy propionate (hereinafter, abbreviated as 'MMP') and cyclohexanone (cyclohexanone) are not significantly different from PGMEA as shown in Table 1 below. It is not easy to remove as distillation. Therefore, in order to obtain high purity PGMEA, the loss of PGMEA which is removed together with MMP becomes large, and the overall recovery rate of PGMEA is low. In some cases, it may be impossible to economically obtain high purity PGMEA.

Table 1

In order to separate a compound having an ester such as MMP, Although it may be considered to convert to other materials through hydrolysis by an acid or alkali catalyst as shown in Fig. 1, in this case, PGMEA, which is a large amount of ester, is also easily broken down due to the ester compound. Occurs.

Banungsik 1

OH * or OH ^" O

_B i R ² , 人^{+ 2} OH

RO ^'H ₂ 0 R ¹ OH wherein R, R ¹ and R ² is a hydrocarbon group of aliphatic or aromatic.

The waste organic solvent treatment method is described in Korean Patent Registration Nos. 10-0446165, 10—0304373 and Korean Patent Application No. 10-2004-0074649, but these are mainly devices for distilling and recovering waste organic solvents. Or it relates to a method of treating with an electrolyte in order to separate the water contained in the waste organic solvent, it does not provide a solution for the treatment of waste organic solvent containing an organic solvent with similar boiling point as described above.

In addition, Korean Patent Registration No. 10—0763504 discloses a method of saliva-based removal of crosslinkable photoresist components in a waste organic solvent by adding an alkaline component to the waste organic solvent. As it is used to remove solids such as pigments, it does not solve the problem of separation of organic solvent impurities such as MMP.

In addition, the Republic of Korea Patent Registration No. 10-0869333 relates to the regeneration method of the waste PGMEA solvent, it proposes a distillation method for separating the MMP and cyclonucleanone having a close boiling point, it is just a general distillation process As described above, it is no different from the general distillation process using the boiling point difference of PGMEA, MMP, and PGMEA and cyclonuclinon. Therefore, the recovery rate is high for the high purity of PGMEA. . SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to purify high organic solvents in high yield by effectively removing similar boiling point impurities from organic solvent mixtures based on propylene glycol monomethyl ether acetate (PGMEA). Is to provide a way.

In order to achieve the above object, the present invention is an organic solvent mixture containing propylene glycol monomethyl ether acetate (PGMEA) as a main component and at least one of propionate and ketone compounds as impurities, d- Provided is a method for purifying an organic solvent, which comprises adding 20 alkoxide compounds and reacting to remove impurities.

In the organic solvent purification method of the present invention, the step of removing the impurity olol preferably comprises a fractional distillation step.

The organic solvent purification method of the present invention converts impurities of propionates or ketones with boiling points similar to those of propylene glycol monomethyl ether acetate to materials having different boiling points, thereby facilitating separation by distillation or the like, thereby increasing the purity of the organic solvent. Makes it possible to purify in high yield. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows the results of gas chromatography analysis of an organic solvent before reaction with an alkoxide in Example 1. FIG. ^'

Figure 2 is a result of analyzing the organic solvent after reacting with alkoxysaad in Example 1 by gas chromatography. DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the present invention will be described in more detail. In order to solve the above-mentioned problems, the present inventors reacted by adding alkoxide compounds to an organic solvent mixture containing PGMEA as a main component and containing impurities of propionates and ketones, thereby producing propionates and ketones. The invention was completed to effectively remove impurities.

The removal mechanism of propionate and ketones according to the present invention is estimated to be the same as the following reaction formula 2, but is not limited to such a mechanism. In general, esters and ketones undergo nucleophilic substitution of ketones with hydroxide ions through alkali reactions. Through this reaction, the ester compound is decomposed into alcohol and acetic acid as shown in Scheme 2 below. However, methyl 3- methoxypropionate (MMP) has alpha hydrogen, and these esters produce beta-keto esters through condensation. The reaction forms an enolate of the ester by an acid-base reaction with alkoxide ions, and the addition of the enolate is completed as the resulting enolate reacts with the carbonyl group to remove alcohol. do.

Banungsik 2

In the above formula, R ¹ to R ⁵ are an aliphatic or aromatic hydrocarbon group. Through this condensation reaction, MMP and cyclonucleus stanones similar in boiling point to PGMEA are converted into high boiling point compounds, and are easily separated from PGMEA through fractional distillation, thereby recovering high-purity PGMEA with high separation efficiency.

According to the organic solvent purification method of the present invention, impurities can be removed by adding alkoxide compounds to the organic solvent containing PGMEA and impurities, and mixing the same. At this time, the mixing method is not particularly limited and the reaction temperature and reaction time are not particularly limited, for example, it is possible to perform for 0.1 to 100 hours at a temperature of -10 to 200 ^° C.

In addition, the organic solvent that has been treated according to the present invention as described above, it is possible to add a process of removing impurities and separating the PGMEA as needed. There is no particular limitation on the separation method and it is preferable to use fractional distillation using a non-point difference, but such a treatment step is only one example, and the present invention is not limited thereto.

Alternatively, the reaction step and the separation step may be performed simultaneously. For example, alkoxide is added to an organic solvent containing PGMEA and impurities, such as reactive distillation, which proceeds with distillation, and the reaction is carried out while distilling to separate high purity PGMEA from the organic solvent. It's fun to retrieve. Alkoxide compounds that can be used in the present invention is preferably selected from the compounds represented by the following formula (1) alone or in combination of two or more. Formula 1

M- (OR ') n Wherein M is Na, K, Co, Ga, Ge, Hf, Fe, Ni, Nb, Mo, La, Re, Sc, Si, Ti, Ta, W, Y or Zr, and R ^* is carbon Linear, branched, or cyclic alkyl groups, n is an integer from 1 to 6; mxn is an integer of 1-20. Preferred alkoxide compounds include sodium meroxide, sodium epoxide, sodium propoxide, sodium isopropoxide, sodium butoxide, sodium methbutoxide, potassium methoxide, potassium eoxide, potassium propoxide Side, Potassium Isopropoxide, Potassium Butoxide, Potassium-Axoxide, Titanium Methoxide, Titanium Eoxide, Titanium Propoxide, Titanium Isopropoxide, Titanium Sub-side, Titanium Iso-side Side , Titanium-2-ethyl nucleoside, aluminum epoxide, aluminum propoxide, aluminum isopropoxide, aluminum prooxide, aluminum ί-butoxide, and combinations thereof, but are not limited thereto. no.

More preferred examples include sodium methoxide (NaOCH ₃ ), sodium ethoxide (NaOC ₂ H ₅ ), potassium-butoxide (KOC ₄ H ₉ ), titanium isopropoxide (Ti (OiPr) ₄ ), aluminum Isopropoxide (Al (OiPr) ₃ ), and mixtures thereof.

The alkoxide compound is preferably added in an amount of 1 to 500 parts by weight based on 100 parts by weight of the total content of propionates and ketone compounds to be removed in an organic solvent. When the amount of the alkoxide compound is in the above range, the decomposition of propionate and ketones is further improved, and the economic efficiency can be further improved by reducing the decomposition of unnecessary PGMEA.

Such a purification method of the present invention can be usefully used to purify organic solvents and organic solvent mixtures derived from waste organic solvents generated in semiconductor and display manufacturing processes.

Impurities that can be effectively removed through the purification method of the present invention include methyl 3-methoxypropionate as the progoonate compounds. Cyclonucleanone, 2-heptanone, these mixtures, etc. are mentioned as a ketone compound. EXAMPLES Hereinafter, the present invention will be described in more detail based on the following examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto. Preparation Example 1 Preparation of Mixed Organic Solvent Sample: Each component of S1 was mixed in a composition as shown in Table 2 below to prepare an organic solvent sample S1. TABLE 2

Examples 1 to 5 and Comparative Examples 1 to 4 Step a) Reaction of the organic solvent sample and the additive

After adding each acid / base additive as shown in Table 3 to 800 g of the mixed organic solvent sample (SI) obtained in Preparation Example 1, the reaction mixture was added to a flask with a separate stirring device and stirred to complete reaction. Step b) Impurity Removal and Recovery of PGMEA

Each semi-coal water obtained in step a) was placed in a 100 mL round bottom flask and heated by a heater to be distilled, followed by fractional distillation using a 30 mm inner column equipped with a 30-sieve tray. PGMEA was recovered. Comparative Examples 5 and 6 PGMEA was recovered in the same manner as in Example 1, except that the mixed organic solvent sample (S1) prepared in Preparation Example 1 was directly distilled without any reaction with any additives. . At this time, Comparative Example 5 confirmed the PGMEA purity at a similar recovery rate to Comparative Examples 1 to 4, Comparative Example 6 confirmed a decrease in the yield when the PGMEA was recovered with high purity of 99.0% or more. Test Example Test Example 1 Evaluation of Degradation Rate for Each Component in the Organic Solvent The semi-aungmul obtained in steps a) of Examples 1 to 5 and Comparative Examples 1 to 6 above. The decomposition rate of each component in the solution was evaluated according to the following equation, and the results are shown in Table 3 below:

Degradation rate (%) = (Amount of each component before treatment-Amount of each component after treatment) I (Amount of each component before treatment) X 100 Table 3

As can be seen in Table 3, in Examples 1 to 5 to which the alkoxide compound according to the present invention is added, almost completely decomposes by selective reaction with an alkoxide to which MMP and cyclonuxanone are added in a mixed organic solvent. It can be seen that PGMEA hardly decomposes. On the other hand, in the case of Comparative Examples 1 to 4 in which Na or KOH was added, the decomposition of cyclohexanone did not occur, and the decomposition rate of MMP was increased but the layer was not separated, and the decomposition degree of PGMEA was increased as the additive content was increased. In comparison, there was a problem that increases. In addition, in Example 1, before and after the reaction with the alkoxide, the organic solvent sample was analyzed by gas chromatography, and the results are shown in FIGS. 1 and 2. As can be seen in Figures 1 and 2, the MMP and cyclonuxanone present in the sample before the reaction, it can be seen that after the reaction ^{'to be} completely removed, it can be seen that other substances are produced as a result of the reaction. When analyzing organic solvents by gas chromatography, the order of the peaks generally has some similarities to the non-pointing order of materials, so MMP and cyclonuxanone are changed to materials with different boiling points. It can be seen. Test Example 2 Evaluation of Purity and Recovery Rate of Recovered PGMEA The purity and recovery rate of PGMEA recovered in Examples b) and Steps b) of Comparative Examples 1 to 6 were evaluated as follows. I showed up.

(1) Purity of recovered PGMEA

The purity of PGMEA was measured using Agilent Technologies' gas chromatography (model: 7890A, equipped with HP-5 columns with a length of 30m and an internal diameter of 0.320mm). (2) Recovery (%) = recovered PGMEA mass / mass of PGMEA in original sample (SI) X 100 Table 4

As can be seen from the results of Table 4, in the case of Examples 1 to 5 in which much decomposition of MMP and cyclonucleanone occurred, the high-purity PGMEA was easily purified and recovered in a distillation process. However, in the case of Comparative Examples 1 to 4 and the Comparative Example 5, which did not undergo a low decomposition rate, although the recovery rate was very low, the purity is very low compared to the Examples. In addition, in the case of increasing the purity as in Comparative Example 6, it can be seen that the recovery rate is more sharply reduced, and further purification of the higher purity is difficult. In the above, the present invention has been described with reference to the above embodiments, which are only examples, and the present invention includes various modifications and other equivalent embodiments which are obvious to those skilled in the art. It should be understood that they can be performed within the scope of the appended claims.

Claims

1.Adding and reacting an alkoxide compound to an organic solvent mixture comprising propylene glycol monomethyl ether acetate (PGMEA) and at least one of propionate and ketone compounds as impurities, removing the impurities Purifying organic solvent, including the process.

2. The method of paragraph 1,

The process of removing the impurities, characterized in that it comprises a fractional distillation process.

3. The crab of paragraph 1,

The organic solvent mixture is derived from the waste organic solvent generated in the semiconductor or display manufacturing process, ^° Organic solvent purification method.

4. according to paragraph 1 '

_. The alkoxide compound is a compound represented by the formula

Method for purifying organic solvent, characterized in that it is used at least one:

Formula 1

M- (OR ') n ^"

Wherein M is Na, Co, Ga, Ge, Hf, Fe, Ni, Nb, Mo, La, Re, Sc, Si, Ti, Ta, W, Y or Zr; R 'is a straight, branched or cyclic alkyl group of m carbon atoms; n is an integer from 1 to 6; mxn is an integer of 1-20.

5. Paragraph 1 or 4,

The C 20 alkoxide compound, sodium mesoside, sodium epoxide, small Sodium Propoxide, Sodium Isopropoxide, Sodium Iboxide, Sodium ί—Butoxide, Potassium Methoxide, Potassium Eoxide, Potassium Propoxide, Potassium Isopropoxide, Potassium Axoxide, Potassium ί-Boxide, Titanium Methoxide, Titanium Eoxide, Titanium Propoxide, Titanium Isopropoxide, Titanium Boxide, Titanium Isooxide, Titanium-2-Ethyl Nucleoside, Aluminum Eoxide, A process for purifying organic solvents, characterized in that it is selected from the group consisting of aluminum propoxide, aluminum isopropoxide, aluminum butoxide, aluminum ί-butoxide, and mixtures thereof.

One

5

6. In accordance with paragraph 1,

Wherein the alkoxide compounds, when the content of the impurities removed to 100 parts by weight, characterized in that it is added in an amount of 1 to 500 parts by weight, organic solvent purification method.

7. The method of paragraph 1,

The reaction is, — characterized in that for 0.1 to 100 hours at a temperature of 10 to 200 ^° C, organic solvent purification method.

8. The method of paragraph 1,

The said propionate compound is methyl 3- methoxy propionate, The purification method of the organic solvent.

9. The method of paragraph 1,

The ketone compound is a cyclonucleanone, 2-heptanone, or a mixture thereof.