KR102119729B1 - Propylen glycol composition and the manufacturing method thereof - Google Patents

Abstract

The embodiment relates to a propylene glycol composition and a method for preparing the same, wherein the propylene glycol composition has a nitrogen content of less than 0.4 ppm, whereby a propylene glycol composition with improved quality and suitable for subsequent processing can be obtained.

Description

Propylene glycol composition and method for manufacturing the same{PROPYLEN GLYCOL COMPOSITION AND THE MANUFACTURING METHOD THEREOF}

Embodiments relate to a propylene glycol composition with the ionic component selectively removed and a method of making the same.

The propylene glycol composition is a raw material that has a wide range of application fields, such as unsaturated polyester unsaturated polyester resin, cosmetics, ointment pharmaceuticals, antifreeze, surfactant, and high-grade polar solvent.

The propylene glycol composition is generally prepared by reacting propylene oxide with water in a molar ratio of 1:1. Therefore, the produced propylene glycol composition may contain impurities that may be introduced from propylene oxide and affect subsequent processes.

Accordingly, research into what impurities are included in the propylene oxide and propylene glycol composition, how these impurities affect the physical properties of propylene glycol, and how to selectively remove the impurities are being conducted.

Embodiments are intended to provide a high-quality propylene glycol composition suitable for application in a subsequent process and a method for producing the same, by selectively removing ionic or nonionic impurities to have a low nitrogen (Nitrogen) content.

Nitrogen content in the composition of the propylene glycol composition according to one embodiment is less than 0.4 ppm.

Method for producing a propylene glycol composition according to one embodiment comprises the steps of (1) purifying the alkylene oxide crude composition; (2) reacting the purified alkylene oxide composition with water; And (3) obtaining a propylene glycol composition. The nitrogen content of the propylene glycol composition is less than 0.4 ppm.

The propylene glycol composition according to the embodiment has a low nitrogen content, thereby improving the quality and is suitable for application in a subsequent process.

Hereinafter, the invention will be described in detail through embodiments. The embodiments are not limited to the contents disclosed below, and may be modified in various forms as long as the gist of the invention is not changed.

In the present specification, when a part “includes” a certain component, it means that the component may further include other components, not exclude other components, unless otherwise stated.

In addition, it should be understood that all numbers and expressions indicating the amount of ingredients, reaction conditions, and the like described in the present specification are modified in all cases with the term "about" unless otherwise specified.

Embodiments provide a propylene glycol composition having a low nitrogen content by selectively removing ionic or nonionic components. The lower the nitrogen content of propylene glycol, the better the physical properties of materials produced in a subsequent process that can be produced using propylene glycol.

The nitrogen content of the propylene glycol composition according to one embodiment is less than 0.4 ppm. The nitrogen content of the propylene glycol composition according to another embodiment is 0.3 ppm or less. The nitrogen content of the propylene glycol composition according to another embodiment is 0.2 ppm or less. Further, the nitrogen content of the propylene glycol composition may be 0 ppm or more, 0.05 ppm or more, or 0.1 ppm or more.

For example, the nitrogen content of the propylene glycol composition is 0.1 or more to less than 0.4 ppm, 0.1 to 0.38 ppm, 0.1 to 0.36 ppm, 0.1 to 0.34 ppm, 0.1 to 0.32 ppm, 0.1 to 0.3 ppm, 0.1 to 0.28 ppm, 0.1 To 0.26 ppm, 0.1 to 0.24 ppm, 0.1 to 0.22 ppm or 0.1 to 0.2 ppm, but is not limited thereto.

The propylene glycol composition may include an ionic component, a nonionic component and a solvent.

The propylene glycol composition may include an ionic component, that is, a cationic component and an anionic component.

Specifically, the cationic component may be one or more selected from the group consisting of NH ₂ ⁺ , NH ₄ ⁺ and molecular sieves having the functional group. For example, the cationic component may include NH ₄ ⁺ . As another example, the cationic component may include NH ₂ ⁺ and NH ₄ ⁺ . For example, the cationic component, but be made of a NH ₄ ^+, but is not limited to such.

Further, the anionic component is NO ₂ ^- can be at least one member selected from the group consisting of the minute, and with it to the functional group itself ^-, NO _3. For example, the anionic component may include NO ₂ ^- . As another example, the anionic component may include NO ₂ ^- and NO ₃ ^- . For example, the anionic component may be made of NO ₂ ⁻ , but is not limited thereto.

The ionic component may include a nitrogen-containing ionic component.

For example, the ionic component may include one or more selected from the group consisting of NH ₂ ⁺ , NH ₄ ⁺ , NO ₂ ^- and NO ₃ ^- . Alternatively, the ionic component may be made of one or more selected from the group consisting of NH ₂ ⁺ , NH ₄ ⁺ , NO ₂ ^- and NO ₃ ^- .

Further, the propylene glycol composition may include a non-ionic component in addition to the ionic component.

For example, the non-ionic component may include an amine-based component.

Specifically, the amine-based components are diisopropylamine, diethylamine, triethylamine, diethanolamine, dimethylethylamine, methyldiethanolamine ), trimethylamine (Trimethylamine) and monoisopropylamine (monoisopropylamine) may include one or more selected from the group consisting of.

The reason for increasing the nitrogen content of the propylene glycol composition is due to the nitrogen-containing ionic component and nitrogen-containing nonionic component in propylene oxide.

In addition, the propylene oxide crude composition may include a solvent.

Specifically, the solvent may include one or more selected from the group consisting of water, methanol, acetaldehyde, propionaldehyde, methyl formate and dimethoxymethane.

The odor index of the propylene glycol composition according to one embodiment is less than 3. The odor strength index of the propylene glycol composition according to another embodiment is 1 or less. Specifically, the odor intensity index of the propylene glycol composition may be 0 to less than 3, 0 to 2, 0 to 1 or 0 to 0.5, but is not limited thereto.

The odor index is an odor of the composition measured by the following criteria.

0: Odorless

1.0: Detected only by experienced personnel.

1.5~2.0: Anyone can sense it, but it is not an unpleasant smell.

2.5~3.0: Detected by everyone and smells fishy.

The propylene glycol composition according to one embodiment includes at least one selected from the group consisting of mono propylene glycol, dipropylene glycol and tripropylene glycol.

The content of the mono propylene glycol may be 60 to 80% by weight based on the total weight of the propylene glycol composition. Specifically, it may be 65 to 80% by weight, 65 to 75% by weight or 65 to 70% by weight, but is not limited thereto.

The content of the dipropylene glycol may be 20 to 30% by weight based on the total weight of the propylene glycol composition. Specifically, it may be 22 to 30% by weight, 22 to 28% by weight, or 22 to 25% by weight, but is not limited thereto.

Method for producing a propylene glycol composition according to one embodiment comprises the steps of (1) purifying the alkylene oxide crude composition; (2) reacting the purified alkylene oxide composition with water; And (3) obtaining a propylene glycol composition; wherein the nitrogen content of the propylene glycol composition is less than 0.4 ppm.

The alkylene oxide crude composition refers to a composition immediately after being prepared by an alkylene oxide production process, and a composition containing unnecessary ionic components and the like in a subsequent process.

The alkylene oxide crude composition may include an alkylene oxide, an ionic component, a nonionic component and a solvent.

The alkylene oxide crude composition may include an ionic component. The ionic component may be a cationic component or an anionic component.

According to an embodiment, the ionic component includes NH ₄ ⁺ , and the content of NH ₄ ⁺ included in the alkylene oxide crude composition is 0.1 to 5 ppm. Specifically, the ionic component contains NH ₄ ⁺ , and the content of NH ₄ ⁺ contained in the alkylene oxide crude composition is 0.1 to 3 ppm, 0.1 to 2.5 ppm, 0.3 to 2 ppm, or 0.5 to 1.5 ppm. However, it is not limited thereto.

According to an embodiment, the ionic component contains NO ₂ ^- , and the content of NO ₂ ^- contained in the alkylene oxide crude composition is 0.1 to 5 ppm. Specifically, the ionic component contains NO ₂ ^- , and the content of NO ₂ ^- contained in the alkylene oxide crude composition may be 0.1 to 3 ppm, 0.1 to 1 ppm, or 0.25 to 0.75 ppm, but is not limited thereto. It does not work.

The ionic component may include a nitrogen-containing ionic component.

For example, the ionic component may include one or more selected from the group consisting of NH ₂ ⁺ , NH ₄ ⁺ , NO ₂ ^- and NO ₃ ^- . Alternatively, the ionic component may be made of one or more selected from the group consisting of NH ₂ ⁺ , NH ₄ ⁺ , NO ₂ ^- and NO ₃ ^- .

The ionic component contains 30 to 90% by weight of the cationic component based on the total weight of the ionic component. Specifically, the ionic component may include 40 to 90% by weight, 50 to 90% by weight, or 50 to 80% by weight based on the total weight of the ionic component. More specifically, the ionic component may include 60 to 80% by weight of the cationic component based on the total weight of the ionic component, but is not limited thereto.

The alkylene oxide crude composition may include a nonionic component in addition to the ionic component. The content of the nonionic component is the same as described above in the propylene glycol composition.

In addition, the alkylene oxide crude composition may include a solvent.

Specifically, the solvent may include one or more selected from the group consisting of water, methanol, acetaldehyde, propionaldehyde, methyl formate and dimethoxymethane.

For example, the alkylene oxide crude composition includes dimethoxymethane (DMM) and methyl formate (MF), and the content of the dimethoxymethane (DMM) and methyl formate (MF) is 10 to 3,000 ppm, It may be 10 to 1,000 ppm, 10 to 500 ppm or 20 to 100 ppm, but is not limited thereto.

The CPR (Controlled Polymerization Rate) of the alkylene oxide crude composition is 0.2 to 20. Specifically, the CPR of the alkylene oxide crude composition may be 0.2 to 10, 0.2 to 5, 0.2 to 2, 0.5 to 3, 0.5 to 2 or 0.8 to 1.5, but is not limited thereto.

Specifically, the CPR is an index indicating the amount of the basic substance in the composition, and is a result of quantifying the amount of neutralized titrated hydrochloric acid (concentration: 0.001 N) after mixing 30 g of the composition with 100 ml of methanol according to the test method of ASTM D6437. . The CPR value may be lowered as ionic or nonionic impurities in the alkylene oxide crude composition are effectively removed.

If the CPR of the alkylene oxide crude composition does not satisfy the appropriate range, it is difficult to control the reactivity in the process of manufacturing the subsequent product using the raw material, and the CPR value of the latter product using the raw material exceeds the product CPR standard. . Therefore, when the CPR value of the alkylene oxide crude composition satisfies an appropriate range, product quality may be improved. Specifically, it is more advantageous to maintain the CPR value of the alkylene oxide crude composition at a maximum of 2.0 or less.

Specifically, as the cationic impurities among the aforementioned ionic impurities are relatively larger than those of the anionic impurities, the cationic impurities remaining after neutralizing the impurities are factors that increase the CPR value of the alkylene oxide crude composition.

Nitrogen content of the alkylene oxide crude composition is 0.2 to 10 ppm. Specifically, the nitrogen content of the alkylene oxide crude composition is 0.2 to 7 ppm, 0.2 to 5 ppm, 0.2 to 3 ppm or 0.2 to 2 ppm. More specifically, the nitrogen content of the alkylene oxide crude composition may be 0.5 to 1.8 ppm, 1.0 to 1.8 ppm or 1.2 to 1.8 ppm, but is not limited thereto.

The factors that increase the nitrogen content of the alkylene oxide crude composition are due to the aforementioned nitrogen-containing ionic components and nitrogen-containing nonionic components.

The alkylene oxide may be ethylene oxide, propylene oxide, butylene oxide, and the like. Specifically, the alkylene oxide may be propylene oxide.

According to one embodiment, the step of purifying the alkylene oxide crude composition is performed prior to performing one or more purification methods selected from the group consisting of an adsorbent use method, an electrochemical method, and a distillation method, in particular, an adsorbent. Before performing the purification method using the alkylene oxide crude composition may be passed through a bead section.

The bead section includes a plurality of beads having an average diameter of 1 to 5 mm. Specifically, the bead section may include a plurality of beads having an average diameter of 1.5 to 4 mm or 2 to 3 mm, but is not limited thereto.

The number of beads per unit volume of the beads included in the bead section is 100 to 100,000 pieces/L. Specifically, the number of beads per unit volume of the bead section may be 1,000 to 80,000 pieces/L, 5,000 to 70,000 pieces/L, 10,000 to 50,000 pieces/L, and 15,000 to 40,000 pieces/L, but is not limited thereto. no.

In addition, the space velocity through which the alkylene oxide crude composition passes through the bead section is greater than 0 to 10 h ⁻¹ or less. Specifically, the space velocity through which the alkylene oxide crude composition passes through the bead section is 0.2 to 5 h ^-1 , 0.2 to 3 h ^-1 , 0.2 to 2 h ^-1 , 0.5 to 2 h ^-1 or 0.8 to 1.5 h ^-1 , but is not limited thereto.

The beads included in the bead section may include an inactive material based on silicalite.

The bead section serves to induce an even dispersion before the alkylene oxide crude composition enters the subsequent purification methods, particularly the adsorbent.

According to one embodiment, the step of purifying the alkylene oxide crude composition may use one or more purification methods selected from the group consisting of an adsorbent usage method, an electrochemical method, and a distillation method.

According to one embodiment, the crude alkylene oxide composition may be passed through an adsorbent.

According to one embodiment, the method of using the adsorbent may be a zeolite-based molecular sieve (Mol-Sieve) or natural clay (Natural Clay).

The zeolite-based molecular sieve may have a structure selected from the group consisting of zeolite A, zeolite X, zeolite beta, zeolite Y, zeolite L and ZSM-12.

The molecular sieve collectively refers to silicon aluminum oxide, and may be an octagonal geometric structure having an inlet of a fine hole made of an oxygen atom ring and intersecting another hole bent at regular intervals between the holes, but is not limited thereto. .

At this time, the pore size of the molecular sieve is greater than 2.3 mm 2 and less than 10 mm 2. Specifically, the pore size of the molecular sieve may be 3 to 10 Å, 3 to 7.5 Å, 3 to 5 Å, 3.5 to 4.5 Å, 3.8 to 4.2 Å or 3.9 to 4.1 Å, but is not limited thereto.

In addition, the shape of the pores of the molecular sieve may be octagonal. Specifically, the molecular sieve has an octagonal microporous shape, and the commercialized product may be manufactured into a spherical, pellet, extruded or the like of about 2 mm by physically bonding the molecular sieve.

The molecular sieve can be adsorbed by selecting impurities smaller than the octagonal fine pores. Alternatively, the negative charge (acid point) of the zeolite series itself of the molecular sieve can adsorb the cationic component present in the alkylene oxide bath composition.

The natural clay may be selected from the group consisting of montmorillonite, kaolinite, sepiolite, bentonite, and diatomite.

The space velocity through which the alkylene oxide crude composition passes through the adsorbent is greater than 0 to 10 h ⁻¹ or less. Specifically, the space velocity through which the alkylene oxide crude composition passes through the molecular sieve is 0.2 to 5 h ^-1 , 0.2 to 3 h ^-1 , 0.2 to 2 h ^-1 , 0.5 to 2 h ^-1 or 0.8 to 1.5 h ^-1 , but is not limited thereto.

In the electrochemical method, a certain amount of a Pd/C catalyst is coated on a graphite foil to produce two electrodes, and then connected to equipment that applies voltage. By immersing the two electrodes in a reactor containing the alkylene oxide bath composition and maintaining a constant voltage for a certain period of time, causative substances, such as ionic components, which increase the CPR value, can be removed by being adsorbed to the electrode. For example, a voltage of 0.85 V may be applied between the two electrodes to maintain it for 2 hours, but is not limited thereto.

In the distillation method, by using the alkylene oxide crude composition using a low-boiling-point material distillation column (Light purge column), it is possible to remove causative substances that increase the CPR value, such as ionic components.

The alkylene oxide composition purified using the above purification method includes an ionic component including a cationic component and an anionic component. At this time, the description of the type of the ionic component is as described in the alkylene oxide crude composition.

In addition, the purified alkylene oxide composition may include a non-ionic component and a solvent in addition to the ionic component, and the description thereof is also as described in the alkylene oxide crude composition.

When the purified alkylene oxide composition includes an ionic component including a cationic component and anionic component, the ionic component contains 10 to 70% by weight of the cationic component based on the total weight of the ionic component. do. Specifically, the ionic component may include 20 to 70% by weight, 30 to 70% by weight, 40 to 60% by weight, or 45 to 55% by weight based on the total weight of the ionic component. It is not limited.

For example, the purified alkylene oxide composition and the content of NH ₄ ⁺ is contained within and wherein the purified alkylene oxide composition of the NH ₄ ⁺ is from 0.05 to 2.5 ppm. Specifically, the content of NH ₄ ⁺ contained in the purified alkylene oxide composition may be 0.1 to 2 ppm, 0.1 to 1 ppm, 0.2 to 0.8 ppm, 0.2 to 0.6 ppm, or 0.4 to 0.6 ppm, but is not limited thereto. It is not.

In addition, the purified alkylene oxide composition contains NO ₂ ^- , and the content of NO ₂ ^- contained in the purified alkylene oxide composition is 0.1 to 5 ppm. Specifically, the content of NO ₂ ⁻ contained in the purified alkylene oxide composition may be 0.1 to 3 ppm or 0.25 to 0.75 ppm, but is not limited thereto.

The purified alkylene oxide composition has a CPR of 0 to 2. Specifically, the CPR of the purified alkylene oxide composition may be 0 to 1.5, 0 to 1.2, 0 to 0.8, 0 to 0.5, 0.1 to 0.5, 0.1 to 0.3 or 0.1 to 0.2, but is not limited thereto.

In the case where the CPR of the purified alkylene oxide composition is in the above range, it not only facilitates the control of reactivity in the process of manufacturing a rear end product using the raw material, but also satisfies the product CPR standard with the lowered CPR value of the produced product itself. It is advantageous.

The purified alkylene oxide composition has a basicity of 0 to 4. Specifically, the basicity of the purified alkylene oxide composition may be 0 to 3, 0 to 2.4, 0 to 1.6 or 0 to 1.0, but is not limited thereto.

Nitrogen content of the purified alkylene oxide composition is 0.1 to 5 ppm. Specifically, the nitrogen content of the purified alkylene oxide composition may be 0.1 to 3 ppm, 0.1 to 2 ppm, 0.2 to 1.5 ppm or 0.4 to 1.1 ppm, but is not limited thereto.

When the nitrogen content of the purified alkylene oxide composition is in the above range, it is advantageous in that the odor of the downstream product using it as a raw material is reduced than when using the crude alkylene oxide crude composition.

Then, a step of reacting the purified alkylene oxide composition with water is performed (step (2)).

The propylene glycol composition may be prepared by reacting an alkylene oxide composition and water at 100 to 200°C, as shown in Scheme 1 below.

[Scheme 1]

Subsequently, a propylene glycol composition can be obtained through the purification process using the boiling point difference through the step (2) (step (3)). The description of the propylene glycol composition is as described above.

The above contents will be described in more detail by the following examples. However, the following examples are only for illustrating the present invention, and the scope of the examples is not limited to these.

<Example>

<Example 1>

100 g of the purified propylene oxide composition was obtained by using 100 g of an alkylene oxide crude composition using a zeolite-based molecular sieve (Mol Sieve).

The propylene oxide composition and water were reacted in a tube reactor. Thereafter, the remaining water was distilled to obtain propylene glycol composition A.

<Comparative Example 1>

The propylene glycol composition B was obtained in the same experiment as in Example 1, except that 100 g of the alkylene oxide crude composition in Example 1 was used without purification.

<Evaluation Example 1-1: CPR measurement>

According to the test method of ASTM D 6437 (Standard Test Method for Polyurethane Raw materials), 30 g of each composition was mixed in 100 ml of methanol, and then neutralized titration with 0.001 N hydrochloric acid to calculate the amount of hydrochloric acid consumed.

<Evaluation Example 1-2: Nitrogen content measurement>

According to the test method of ASTM D 6437 (Standard Test Method for Polyurethane Raw materials), after diluting 0.6 g of each composition in 3 g of toluene, the wavelength emitted by nitrogen dioxide generated by burning in oxygen and argon is quantitatively analyzed Did.

<Evaluation Example 1-3: Measurement of odor index>

The odor intensity index of each composition was measured according to the following criteria.

0: Odorless

1.0: Detected only by experienced personnel.

1.5~2.0: Anyone can sense it, but it is not an unpleasant smell.

2.5~3.0: Detected by everyone and smells fishy.

Table 1 shows the results of the evaluation examples 1-1 and 1-2.

Example 1 Comparative Example 1 CPR of purified alkylene oxide composition 0 0.5 No purification step Nitrogen content in purified alkylene oxide composition (ppm) 0 0.4 No purification step Odor of propylene glycol composition 1.0 3.0 Of propylene glycol composition
Nitrogen content (ppm) 0.2 0.4

As shown in Table 1, it can be seen that the nitrogen content and odor of the propylene glycol composition after the alkylene oxide purification step of Example 1 are lower than that of Comparative Example 1 in which the alkylene oxide purification step was not performed.

Claims (13)

Nitrogen content in the composition is 0.1 ppm or more to less than 0.4 ppm,
The nitrogen is derived from a nitrogen-containing ionic component and a nitrogen-containing nonionic component in propylene oxide, a propylene glycol composition. According to claim 1,
The nitrogen content is 0.1 ppm or more to 0.3 ppm or less, a propylene glycol composition. According to claim 1,
The nitrogen content is 0.1 ppm or more to 0.2 ppm or less, a propylene glycol composition. According to claim 1,
Propylene glycol composition having an odor index of less than 3. According to claim 1,
A propylene glycol composition having an odor index of 1 or less. According to claim 1,
The propylene glycol composition comprises a propylene glycol composition comprising at least one selected from the group consisting of mono propylene glycol, dipropylene glycol and tripropylene glycol. The method of claim 6,
The content of the mono propylene glycol, based on the total weight of the propylene glycol composition, 60 to 80% by weight, propylene glycol composition. The method of claim 6,
Propylene glycol composition, the content of the dipropylene glycol is 20 to 30% by weight, based on the total weight of the propylene glycol composition. (1) purifying the propylene oxide crude composition;
(2) reacting the purified propylene oxide composition with water; And
(3) obtaining a propylene glycol composition; including,
Nitrogen content of the propylene glycol composition is 0.1 ppm or more to less than 0.4 ppm,
The nitrogen is derived from a nitrogen-containing ionic component and a nitrogen-containing nonionic component in propylene oxide, a method for producing a propylene glycol composition. The method of claim 9,
The step of purifying the propylene oxide crude composition is to use one or more purification methods selected from the group consisting of an adsorbent use method, an electrochemical method, and a distillation method. The method of claim 10,
The method of using the adsorbent is a method for producing a propylene glycol composition using a zeolite-based molecular sieve (Mol-Sieve) or natural clay. The method of claim 11,
The zeolite-based molecular sieve has a structure selected from the group consisting of zeolite A, zeolite X, zeolite beta, zeolite Y, zeolite L and ZSM-12, a method for producing a propylene glycol composition. The method of claim 11,
The natural clay is selected from the group consisting of montmorillonite, kaolinite, sepiolite, bentonite, and diatomite.