KR20120008746A

KR20120008746A - 1,3-propanediol refining method using a reactive extraction

Info

Publication number: KR20120008746A
Application number: KR1020100069774A
Authority: KR
Inventors: 김창현; 이창규
Original assignee: 주식회사 스몰랩
Priority date: 2010-07-20
Filing date: 2010-07-20
Publication date: 2012-02-01

Abstract

PURPOSE: A method for purifying 1,3-propandiol with high purity using a glycerin fermenting strain is provided to cheaply obtain 1,3-propandiol of a high yield. CONSTITUTION: A method for purifying 1,3-propandiol comprises a step of purifying 1,3-propandiol from fermentation liquid expressed using strains and a step of selectively or serially extracting the fermentation liquid at pH 2-5 using an amine-based extracting agent. The fermentation liquid is prepared using K. peumoniae M5a1 or K. Peumoniae DSM2026 at established optimal fermentation condition.

Description

Purification of 1,3-propanediol using reaction extraction {1,3-PROPANEDIOL REFINING METHOD USING A REACTIVE EXTRACTION}

The present invention relates to a method for efficiently purifying high purity 1,3-propanediol from a fermentation broth in which a large amount of 1,3-propanediol is expressed using a strain, and more specifically, an extraction process and a reaction. The present invention relates to a method for obtaining high purity 1,3-propanediol by selectively or sequentially performing an extraction step and a distillation step.

1,3-propanediol is a monomer of poly-trimethylene terephthalate (PTT). Conventional PTT is a condensate of terephthalic acid (TPA) or dimethyl terephthalate (DMT) and 1,3-propanediol, and is a resin having a very similar chemical structure as well as a polymerization method with polyethylene terephthalate (PET). The melting point of PTT is 225 ^o C, glass phase transition temperature (T _g ) is 45-47 ^o C, and the stiffness is similar to PET and the processability is better than PET. PTT also has the same elasticity as spandex and the durability of polyester. In conclusion, PTT is a resin that bridges the properties between PET and PBT (Polybutylene terephthalate).

The global market size of PTT is about 250,000 tons, and its size is expected to grow to 2 million tons / year, which is 5% of the PET fiber market since 2010. Will follow. Recently, as biomass-derived PTT synthesis becomes possible, the possibility of PTT application as an eco-friendly bioplastic is increasing.

The main raw material of PTT is 1,3-propanediol, which has been produced mainly through chemical synthesis, but recently, production methods through fermentation of biomass have been studied. However, the biggest problem in the production of 1,3-propanediol through biological processes is that the process of removing 1,3-propanediol from fermentation broth is inefficient. Due to these factors, most of 1,3-propanediol has been produced by ethylene oxide hydroformylation method or chemical process through acrolein hydration.

The fermentation broth contains many impurities from fermentation, and the removal of these impurities has a great effect on the economics and practical use of the products produced by fermentation. The 1,3-propanediol fermentation broth obtained from glycerin fermentation contains 100 g / L of 1,3-propanediol, 35 g / L of 2,3-butanediol, 13 g / L of succinic acid, 5 g / L of acetic acid, and 3 g / L of lactic acid. Some media components may be included. It is known that the separation and purification processes account for about 40% to 70% of the production of 1,3-propanediol using the fermentation process.

Conventional techniques related to the separation and purification of 1,3-propanediol are pretreatment processes for separating impurities and aliphatic organic acids using semipermeable membranes (Geroge KF, Dahuron L., Robson JH, Keller II GE, US Patent 5,031,434), Precipitation (Woyciesjes PM, Gershun AV, Woodward SM, US Pat. There is.

In the production of 1,3-propanediol by glycerin fermentation, a general sequential separation process is performed through four stages: filtration, electrodialysis, evaporation, and vacuum distillation. In the filtration process, cells are removed from the fermentation broth, and electrodialysis is a process for removing impurities such as succinic acid, acetic acid, and lactic acid contained in the fermentation broth. The evaporation concentrates 1,3-propanediol and 2,3-butanediol as water evaporates, and finally, 1,3-propanediol and 2,3-butanediol are separated by distillation under reduced pressure. The following is a brief review of electrodialysis and evaporation which are the core.

Recently, various membrane processes such as precision, ultrafiltration, nanofiltration and reverse osmosis have been used (Ames T. T. US Pat. No. 6361983) and some have been used in connection with electrodialysis. Electrodialysis is based on the electrical movement of ions through an ion exchange membrane that allows the passage of cations or anions. It has the advantages of rapid treatment, removal of non-ion molecules, and non-product formation, but the ion exchange membrane in the electrodialysis device is not only expensive. It is inevitable. Therefore, when it is applied to the actual commercial production scale, it is not used until the commercialization stage due to the problem of drastically reducing the operational efficiency (see Lee EK, "Recovery of lactic acid from fermentation broth using electrodialysis", KAIST Ph.D.) Thesis, 1998, Zeikus JG, Elankovan P. and Grethlein A., Chem. Proc., 58 (7): 71-73, 1995, CN 1191220C, US Patent 5,034,134).

The evaporation method is used to remove the water that accounts for most of the fermentation broth from the fermentation broth from which the organic acid is removed. As with other fermentation processes, evaporation is known to be the most energy-consuming process for the separation and purification of 1,3-propanediol.

The present invention is to solve the above-mentioned problems, and to implement a 1,3-propanediol purification method that can improve the problems with the glycerin fermentation 1,3-propanediol purification method to date.

In order to achieve the above object, the present invention is a physical extraction step (Physical extraction), reaction extraction step to simulate the fermentation broth to express a large amount of 1,3-propanediol through K. peumoniae using glycerin as a carbon source By applying selectively or sequentially. In addition, vacuum distillation can be applied for the final purification of 1,3-propanediol and 2,3-butanediol.

According to the present invention, it is possible to solve the problems of the existing organic acid separation and 1,3-propanediol concentration method leading to the conventional electrodialysis and evaporation method, and in accordance with the present invention 1, Production of 3-propanediol becomes possible. 1,3-propanediol produced according to the present invention is utilized as a monomer for the production of PTT so that PTT can be used as a bioplastic.

1 is a flowchart of a method for separating 1,3-propanediol from fermentation broth.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

1 is a flowchart showing a purification method according to the present invention.

In the present invention, 1,3-propanediol simulated fermentation broths were subjected to fermentation broths expressed in large amounts by K. peumoniae M5a1 or K. peumoniae DSM2026 , which have recently been analyzed by metabolic circuit analysis and optimum fermentation conditions. However, the present invention is not limited to the fermentation broth by the above strains, but is also applied to the fermentation broth by all strains expressing 1,3-propanediol in addition to the above strains.

In fermentation broths induced to express large amounts of 1,3-propanediol, not only 1,3-propanediol but also various impurity organic acids and 2,3-butanediol are present together.

The start of the purification according to the present invention is a centrifugation process to remove solid fermentation microorganisms from fermentation broths in which 1,3-propanediol is expressed in large amounts. At this time, a microseparation process for removing some of the glycerin and fine solids used as the fermentation medium may be used. The fermentation broth from which the solid is removed is subjected to an extraction process for recovering 1,3-propanediol and 2,3-butanediol.

In the extraction process, 1,3-propanediol and 2,3-butanediol are selectively extracted using an organic solvent which is not mixed with an aqueous phase including an alcoholic extractant. At this time, succinic acid, lactic acid and acetic acid salt contained in fermentation broth should not be extracted. As the extraction solvent having selectivity to 1,3-propanediol and 2,3-butanediol and no selectivity to organic acid salts, alcohol-based 1-butanol was used. However, the present invention is not limited to the above extraction solvent, and is applied to the alcoholic extraction solvent including the above extraction solvent. Through this process, most of the water is recycled and almost all 1,3-propanediol and 2,3-butanediol are dissolved in 1-butanol, and some water is dissolved together.

When the organic phase including 1,3-propanediol, 2,3-butanediol and some water obtained in the physical extraction process is distilled off, fractional distillation is carried out due to the difference in boiling point, and most of 1-butanol leaves the top of the distillation column. 3-propanediol and 2,3-butanediol can be separated into the intermediate recovery of the tower depending on the difference in boiling points.

The residual phase remaining after the physical extraction process is an aqueous phase in which organic acid salts are dissolved, and a reaction extraction process is applied to remove the organic acid from the aqueous phase. The reaction extraction process is carried out using an amine extractant for the residual phase in which 1,3-propanediol and 2,3-butanediol are removed by an alcoholic extraction solvent, that is, an aqueous phase containing an organic acid. The extraction process in the present invention utilizes long chain tertiary amines, which form complexes of amines and organic acids to separate the resulting amine-organic acid salts into the organic phase. Extraction with this tertiary amine is based on the basicity of the amine. Compared with other purification methods including electrodialysis, the reaction extraction process in the present invention operates at room temperature and atmospheric pressure and consumes less energy because it does not consume any energy other than stirring. In addition, the reaction extraction shows high selectivity and extraction efficiency, and can minimize the consumption of chemicals put into the process by solvent recovery after extraction.

Hereinafter, the present invention will be described in detail by preferred embodiments of the present invention.

Example 1: 1,3- in aqueous solution With propanediol 2,3- Butanediol extraction

An extraction process was performed to obtain 1,3-propanediol from the aqueous phase containing 1,3-propanediol. K. peumoniae M5a1 10 ml of the supernatant was taken after preparing an aqueous solution that simulated the fermentation broth expressed by. The composition of the simulated aqueous solution is 100 g / L of 1,3-propanediol, 35 g / L of 2,3-butanediol, 13.5 g / L of succinic acid, 4.25 g / L of acetic acid, and 3 g / L of lactic acid. Composition. The extraction solvent used was 1-butanol. The mixing ratio of the solvent was 1: 1 with the same volume as the aqueous phase. After extraction, the centrifuge was operated at 4,000 rpm for 5 minutes for phase separation.

Test Example 1: extraction process After execution 1,3- Propanediol Extraction efficiency analysis

After performing the extraction process according to Example 1, HPLC equipped with an Aminex HPX-87H column (Bio-Rad, USA) was used to quantitatively analyze 1,3-propanediol and 2,3-butanediol. The detector for analysis used a refractive index detector. As standard materials, 1,3-propanediol (99.0%, Fluka) and 2,3-butanediol (99.0%, Fluka) were used. The results according to Example 1 are shown in Table 1.

Composition after performing extraction process 1,3-propanediol 2,3-butanediol Initial concentration Concentration after extraction Initial concentration Concentration after extraction 1-butanol 100 g / L 25 g / L 35 g / L 10 g / L

As shown in Table 1, it was confirmed that 1,3-propanediol and 2,3-butanediol can be effectively separated through the reaction extraction process. However, compared to 1,3-propanediol and 2,3-butanediol, organic acids such as succinic acid, acetic acid and lactic acid were not extracted.

Example 2: 1,3- Propanediol Extraction of reaction to remove organic acid from simulated fermentation broth

In Example 1 above, in order to remove the organic acid included in the residual solution from which 1,3-propanediol and 2,3-butanediol were removed, the same volume of the amine-based extractant was mixed. The pH was adjusted to a range of 2.7 ~ 6.1 and then extracted for 1 hour at room temperature. After extraction, the centrifuge was operated at 4,000 rpm for 5 minutes to conduct phase separation.

Test Example 2: Composition Analysis and Organic Acid Removal Efficiency after Reaction Extraction

In order to quantitatively analyze the organic acid after performing the extraction process according to Example 2, an HPLC equipped with an organic acid column (Supelcogel C-610H, 300 mm 7.8 mm, Supelco, USA) was used. The detector for the analysis used a UV / Visible detector (Waters 2487). Succinic acid (99.9%, Sigma), lactic acid (20%, Sigma), acetic acid (99%, Junsei) was used as a standard. The results according to Example 1 are shown in Table 1.

Composition after performing extraction process Suche mountain Acetic acid Lactic acid Initial concentration Concentration after extraction Initial concentration Concentration after extraction Initial concentration Concentration after extraction pH 2.91 13.5 g / L 0.41 g / L 4.25 g / L 0.47 g / L 3 g / L 0.03 g / L pH 3.80 13.5 g / L 2.30 g / L 4.25 g / L 1.00 g / L 3 g / L 1,28 g / L pH 4,82 13.5 g / L 7.87 g / L 4.25 g / L 2.12 g / L 3 g / L 1.29 g / L pH 6.08 13.5 g / L 13.1 g / L 4.25 g / L 3.75 g / L 3 g / L 1.30 g / L

As shown in Table 2, it was confirmed that the impurity organic acids generated simultaneously with 1,3-propanediol were effectively removed through the reaction extraction process.

As described above, according to the present invention, it is possible to solve the problems of the existing organic acid separation and 1,3-propanediol concentration method leading to the conventional electrodialysis and evaporation method. It is possible to produce 1,3-propanediol at low cost. 1,3-propanediol produced according to the present invention is utilized as a monomer for the production of PTT so that PTT can be used as a bioplastic.

Claims

A method for purifying 1,3-propanediol from a fermentation broth expressed using a strain, wherein the 1,3-propanediol purification method is characterized in that the extraction step, the reaction extraction step is performed selectively or sequentially.

The method for purifying 1,3-propanediol according to claim 1, wherein the extraction process is performed on the aqueous solution of 1,3-propanediol obtained as a result of the reaction extraction process.

The method of claim 1, wherein the reaction extraction process is performed using an amine extractant.

The method of claim 1, wherein the extraction process is 1,3-propanediol purification method, characterized in that carried out at a pH value in the range of 2 to 5.

The method of claim 1, wherein the extraction step is 1,3-propanediol purification method characterized in that carried out using an alcoholic extractant.