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KR-20260062539-A - METHOD FOR PREPARATION OF ACRYLIC ACID

KR20260062539AKR 20260062539 AKR20260062539 AKR 20260062539AKR-20260062539-A

Abstract

The present invention relates to a method for producing acrylic acid comprising the step of converting 3-hydroxypropionic acid into acrylic acid at a specific temperature under an organic solid acid catalyst.

Inventors

  • 김경식
  • 서석재
  • 홍석광
  • 이동규
  • 최재훈
  • 정대연

Assignees

  • 주식회사 엘지화학

Dates

Publication Date
20260507
Application Date
20241029

Claims (12)

  1. A method for producing acrylic acid, comprising the step of converting 3-hydroxypropionic acid into acrylic acid at a temperature of 100°C or higher and 145°C or lower under an organic solid acid catalyst.
  2. In paragraph 1, Prior to the step of converting 3-hydroxypropionic acid to acrylic acid at a temperature of 100°C or higher and 145°C or lower under the above organic solid acid catalyst, A method for producing acrylic acid, further comprising the step of melting the above organic solid acid catalyst.
  3. In paragraph 2, A method for manufacturing acrylic acid, wherein the melting temperature is 100 ℃ or higher and 160 ℃ or lower.
  4. In paragraph 1, A method for producing acrylic acid, wherein the above conversion is carried out under a pressure of 100 torr or more and 500 torr or less.
  5. In paragraph 1, A method for producing acrylic acid, wherein the above organic solid acid is an organic acid having one or more sulfonic acid groups or phosphonic acid groups.
  6. In paragraph 5, A method for producing acrylic acid, wherein the organic acid having one or more sulfonic acid groups or phosphonic acid groups is p-toluenesulfonic acid (p-TSA) or phenylphosphonic acid.
  7. In paragraph 1, A method for manufacturing acrylic acid, wherein the conversion rate to acrylic acid is 70% or more and 95% or less.
  8. In paragraph 1, A method for manufacturing acrylic acid, wherein the purity of the acrylic acid is 80% or higher.
  9. In paragraph 1, A method for producing acrylic acid in which poly(3-hydroxypropionate) is further produced by the above conversion.
  10. In Paragraph 9, A method for producing acrylic acid, wherein the conversion rate to the above poly(3-hydroxypropionate) is 5% or more and 30% or less.
  11. In Paragraph 9, A method for producing acrylic acid, wherein the number average molecular weight of the above poly(3-hydroxypropionate) is 800 g/mol or more and 2,000 g/mol or less.
  12. In paragraph 1, A method for producing acrylic acid, wherein the above 3-hydroxypropionic acid is continuously fed into a reactor at a rate of 0.5 ml/min or more and 3.0 ml/min or less.

Description

Method for Preparation of Acrylic Acid The present invention relates to a method for producing acrylic acid from 3-hydroxypropionic acid. Acrylic acid is a commercially important chemical with various applications in the food, cosmetics, pharmaceutical, and polymer industries. Generally, a two-stage oxidation method is used to produce acrylic acid. This involves converting propylene into acrolein by catalytic gas-phase oxidation in the presence of an oxide catalyst using a stationary-bed multi-tube reactor, and then producing acrylic acid by catalytic gas-phase oxidation of the obtained acrolein. Although propylene is readily available from fossil fuels such as petroleum, its price is rising due to increasing petroleum shortages. Since propylene is a non-renewable resource, there is a demand to manufacture it using renewable resources as raw materials from the perspective of reducing environmental burden. Attempts are being made to economically produce acrylic acid on a commercial scale using renewable resources such as biomass. As a method for producing acrylic acid from biomass, acrylic acid can be prepared by dehydrating lactic acid or 3-hydroxypropionic acid (3-HP), which are natural products and readily available. Generally, the dehydration reaction to convert acrylic acid using 3-hydroxypropionic acid as a starting material proceeds at high temperatures of approximately 200°C or higher under strong acids such as sulfuric acid, which causes corrosion of the reaction equipment or shortens the lifespan of the equipment and poses a safety risk to workers. Hereinafter, embodiments of the present invention will be described in more detail in the following examples. However, the following examples are merely illustrative of embodiments of the present invention, and the content of the present invention is not limited by the following examples. Example 1 A distillation unit was installed in a 500 ml flask, 20 g of p-toluenesulfonic acid (p-TSA) was added, and the pressure was reduced to 500 torr. Subsequently, the temperature was raised to 150 °C to melt the p-toluenesulfonic acid, and an aqueous solution containing 3-hydroxypropionic acid and p-methoxyphenol (weight ratio of 100:1) at a concentration of 560 g/L was injected into the reactor at a rate of 1.5 ml/min, and the 3-hydroxypropionic acid was converted to acrylic acid at 140 °C. After the addition of 3-hydroxypropionic acid was completed, the temperature was lowered to room temperature and the pressure was switched to atmospheric pressure to finally terminate the reaction. Example 2 3-hydroxypropionic acid was converted to acrylic acid in the same manner as in Example 1, except that 20 g of phenylphosphonic acid was used instead of 20 g of p-toluenesulfonic acid (p-TSA). Comparative Example 1 A distillation unit was installed in a 500 ml flask, 100 g of phosphoric acid and 90 g of heat oil (type: Therminol 62) were added, and the temperature was raised to 230 ℃. Subsequently, an aqueous solution containing 3-hydroxypropionic acid and mequinol (weight ratio of 100:1) at a concentration of 560 g/L was injected into the reactor at a rate of 1.5 ml/min, and the 3-hydroxypropionic acid was converted to acrylic acid at 200 °C. Afterward, once the injection of 3-hydroxypropionic acid was completed, the temperature was lowered to room temperature and the pressure was switched to atmospheric pressure to finally terminate the reaction. evaluation 1. Conversion rate and purity measurement The conversion rate to acrylic acid, the purity of acrylic acid, and the conversion rate to poly(3-hydroxypropionate) (P3HP) of the above examples and comparative examples were measured by gas chromatography-mass spectrometry (GC/MS). 2. Measurement of the number-average molecular weight of poly(3-hydroxypropionate) The weight-average molecular weight, number-average molecular weight, peak molecular weight, and polydispersity index (PDI) of the poly(3-hydroxypropionate) (P3HP) of the above examples and comparative examples were measured by gel permeation chromatography (GPC: Waters Alliance e2695). - Solvent: chloroform (eluent) - Flow rate: 1.0 ml/min - Column temperature: 40 ℃ - Standard: Polystyrene Acrylic acid conversion rate (%)Acrylic acid purity (%)P3HP number average molecular weight (g/mol)P3HP Conversion Rate (%)Example 18299.511,00018Example 27099.281,00030Comparative Example 19264.69-- According to Table 1 above, Examples 1 and 2 showed a high conversion rate to acrylic acid of 70% or more and a high purity of 99.28% or more, and it was confirmed that in addition to acrylic acid, poly(3-hydroxypropionate) with a number average molecular weight of 1,000 g/mol could be obtained. On the other hand, Comparative Example 1 is predicted to have a low final yield because the purity of acrylic acid is significantly low, and it was confirmed that poly(3-hydroxypropionate) is not recovered due to the solvent and/or heat transfer oil used during the reaction. In addition, it w