KR20080112201A - Method of preventing generation of heavy ingredient of methyl ethyl ketone - Google Patents

Abstract

A method of preventing the generation of a heavy ingredient of methyl ethyl ketone in which a dimerization-preventive material is used at least as that surface of a purification apparatus or storage apparatus (50) which is in contact with methyl ethyl ketone. The dimerization-preventive material for use in the purification apparatus preferably is stainless steel, while the dimerization-preventive material for use in the storage apparatus (50) preferably is zinc or aluminum. ® KIPO & WIPO 2009

Description

METHOD OF PREVENTING Methyl ETHYLENE IN HEAVY COMPOUND {METHOD OF PREVENTING GENERATION OF HEAVY INGREDIENT OF METHYL ETHYL KETONE}

The present invention relates to a method for preventing the generation of heavy powders of methyl ethyl ketone. More specifically, the present invention relates to a method for preventing the production of heavy components by dimerization of methyl ethyl ketone during the production or storage of methyl ethyl ketone, and to a purification or storage facility for methyl ethyl ketone.

Methyl ethyl ketone (MEK) is a compound mainly useful as a solvent, and can be synthesized by dehydrogenation of 2-butanol (see Non-Patent Document 1, for example). Hereinafter, the manufacturing process of methyl ethyl ketone is demonstrated easily.

1 is a schematic flow chart showing a process for producing methyl ethyl ketone.

2-butanol (shown as SBA in the figure), which is a raw material, causes dehydrogenation in the dehydrogenation reaction column 10 to become methyl ethyl ketone (shown as MEK in the figure). Next, it is sent to a MEK fractionation tower 20 to separate the raw material and methyl ethyl ketone. In the fractionation column 20, methyl ethyl ketone is taken out from the column top and 2-butanol is taken out from the column bottom. The recovered 2-butanol is reused as a raw material. Since methyl ethyl ketone after fractionation contains a small amount of water as a by-product, it is dehydrated in the dehydration column 30. Subsequently, by removing the heavy component produced by the distillation of methyl ethyl ketone or the like, which is further sent to the purification column 40, methyl ethyl ketone of a purity to be produced is produced and stored in the storage facility 50.

Thus, there existed the following problems about the methyl ethyl ketone synthesize | combined and refine | purified.

1. Heavy components increased during storage at storage facilities, which sometimes did not meet product specifications.

2. As a result of the separation operation in the purification column, the methyl ethyl ketone after purification should contain almost no heavy component, but a slight amount of heavy component remained after purification.

[Nonpatent Literature 1] Chemical Engineering Vol. 50, No. 8 (1986, Japan), page 565

(Initiation of invention)

(Tasks to be solved by the invention)

This invention is made | formed in view of the above-mentioned problem, and provides the method of preventing generation | occurrence | production of the heavy component which reduces the purity of methyl ethyl ketone.

(Means to solve the task)

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject, the present inventors came to pay attention to the material of the installation used in a refining process or a storage part. In refining plants and storage plants, inexpensive materials such as carbon steel are generally used as long as they do not handle corrosive components such as acids. Also in the production of methyl ethyl ketone, carbon steel was used because there was no component that corrodes the equipment.

However, when carbon steel oxidized, it was confirmed that iron oxide became a catalyst and dimerized methyl ethyl ketone. Thus, the inventors have found that dimerization of methyl ethyl ketone can be prevented by using a material suitable for equipment in contact with methyl ethyl ketone, and completed the present invention.

Industrial Applicability According to the present invention, the following method for preventing the generation of heavy components of methyl ethyl ketone can be provided.

1. A method for preventing the production of heavy content of methyl ethyl ketone using a dimerization prevention material on at least a contact surface with methyl ethyl ketone in a purification facility or a storage facility.

2. The method for preventing the production of heavy content of methyl ethyl ketone according to the item 1, wherein the dimerization prevention material is zinc, aluminum, zinc aluminum alloy, tin, stainless steel, fluorine resin or polyolefin resin.

3. The method for preventing the production of heavy content of methyl ethyl ketone according to the above 2 item, wherein the dimerization prevention material used in the refining equipment is stainless steel.

4. The method for preventing the production of heavy component of methyl ethyl ketone according to the item 3, wherein the refining equipment is a condenser for cooling methyl ethyl ketone and / or a receiver receiving temporarily.

5. The method for preventing the production of heavy content of methyl ethyl ketone according to 2 above, wherein the dimerization prevention material used for the storage facility is zinc, aluminum, zinc aluminum alloy or tin.

6. Purification or storage facility for methyl ethyl ketone, wherein at least the contact surface with methyl ethyl ketone is made of a dimerization preventing material.

In the method for preventing the production of heavy content of methyl ethyl ketone of the present invention, since dimerization of methyl ethyl ketone during the purification step or storage can be prevented, it is very suitable for maintaining the quality of the product.

1 is a schematic flow chart showing a purification process of methyl ethyl ketone.

Fig. 2 is a schematic flow chart showing a process for producing methyl ethyl ketone.

(The best form to carry out invention)

The method for preventing the production of heavy content of methyl ethyl ketone of the present invention is characterized in that a dimerization prevention material is used for at least a contact surface with methyl ethyl ketone in the purification or storage facility of methyl ethyl ketone.

1 is a schematic flow chart showing a purification process of methyl ethyl ketone. FIG. 1 shows the purification process of methyl ethyl ketone dehydrated by the dehydration column 30 shown in FIG.

The dehydrated methyl ethyl ketone is distilled off by the purification column 40 and recovered as gas from the column top. The methyl ethyl ketone of the gas is cooled by the condenser 42 to liquefy, and is taken into the receiver 44. Methyl ethyl ketone collected in the receiver 44 is sent to the purification tower 40 again as needed, and heavy content is removed until it meets product specifications. On the other hand, when the specification is satisfied, it is cooled to room temperature by the cooler 46 and stored in the storage facility 50. In addition, methyl ethyl ketone is transported by the pump (P).

In the method for preventing the generation of heavy powder of the present invention, a dimerization prevention material is used for a storage facility such as a condenser 42, a receiver 44 or a cooler 46, and / or a storage facility such as a storage tank.

As a dimerization prevention material, metal materials, such as zinc, tin, stainless steel, aluminum, a zinc aluminum alloy, fluorine-type resins, such as polytetrafluoroethylene, resin materials, such as a polyolefin resin, etc. can be used. Moreover, the thing which formed the coating film which consists of these hydroxides by processing a silica coating film, zinc, aluminum, etc. with water can also be used (sealing).

In addition, since the dimerization prevention material should just be used for the contact surface of methyl ethyl ketone and a facility, for example, the whole installation may be formed from a dimerization prevention material, and plating or thermal spraying may be carried out on a contact surface, for example. Etc., a film made of a dimerization prevention material may be formed.

In this invention, it is preferable that the dimerization prevention material used for a refinery installation is stainless steel. In the purification step, methyl ethyl ketone is at a high temperature (80 ° C. or higher) until cooled by a cooler. Therefore, for example, in a refining installation using zinc or tin plating on carbon steel, methyl ethyl ketone may be precipitated due to high temperature, or internal carbon steel may precipitate due to peeling or cracking. There is a risk of dimerization. For this reason, it is preferable to use stainless steel especially for the capacitor | condenser and / or receiver which contact | connect a high temperature methyl ethyl ketone. Moreover, as stainless steel, SUS304, SUS316, SUS405, and SUS410 are preferable.

On the other hand, the dimerization prevention material used for a storage installation has preferable zinc, aluminum, a zinc aluminum alloy, or tin, and it is especially preferable that it is zinc or aluminum. Since methyl ethyl ketone which has passed through the cooler is cooled down to room temperature, there is no fear of the above-mentioned high temperature damage. Therefore, it is preferable to use the equipment which consists of a cheaper material structure, for example, the equipment which sprayed zinc, aluminum, etc. to the contact surface of carbon steel.

As described above, the purification equipment or storage equipment for methyl ethyl ketone of the present invention is characterized in that at least the contact surface with methyl ethyl ketone is made of a dimerization preventing material. As such a facility, there exists a facility which consists of stainless steel, and the facility which sprayed zinc, aluminum, etc. to carbon steel, for example. These can be manufactured by a well-known method in the chemical plant field.

By using the purification equipment or storage facility for methyl ethyl ketone of the present invention, dimerization of methyl ethyl ketone can be prevented.

Hereinafter, as an evaluation example, the result of evaluation about the increase of the heavy content when various materials are immersed in methyl ethyl ketone is demonstrated.

Assessment Methods

Each sample was put into the glass container with methyl ethyl ketone (MEK), it immersed in the thermostat maintained at the fixed temperature, and the heavy content was measured by the gas chromatograph for every elapsed time. In addition, the heavy content was also measured about the blank (blank: MEK only) for each test.

(Evaluation Example 1)

Iron rust collected from an open tank made of carbon steel and iron powder, which is a piece of crushed carbon steel without rust, were each collected by 1 g. These were separately put in a glass container and immersed in 50 ml of MEK (made by Idemitsukosan Co., Ltd.). The production amount of the heavy content when the immersion temperature was 15 degreeC-50 degreeC was measured. Table 1 shows the measurement results.

From this result, it can be confirmed that iron rust (iron oxide) promotes dimerization of MEK.

(Evaluation Example 2)

A zinc-sprayed carbon steel sheet (30 mm x 30 mm x 3 mm thickness, a thickness of a zinc layer of 80 µm: sample A) and a sample subjected to Si sealing treatment (sample B) were produced, respectively. These samples were immersed in 50 ml of MEK, and the production | generation amount of the heavy content when the immersion temperature was 30 degreeC or 50 degreeC was measured. The measurement results are shown in Table 2. In all samples, the production of heavy powder is suppressed as compared with Evaluation Example 1.

In the table, the unit of the heavy amount is (wtppm).

Sample A: Zinc sprayed carbon steel

Sample B: The sample A was hydrolyzed and coated with an alcohol solvent silica sol (tetraethyl orthosilicate, manufactured by Kanto Chemical Co., Ltd.) and sealed.

(Evaluation Example 3)

Each sample (60 mm x 50 mm x 6 mm thickness) described below was immersed in 200 ml of MEK, and the amount of heavy powder produced when the immersion temperature was 35 deg. The measurement results are shown in Table 3. In all samples, the production of heavy powder is suppressed as compared with Evaluation Example 1.

Sample C: Zinc-sprayed (zinc thickness 80 µm) on carbon steel

Sample D: the sample C Zn (OH) ₂ to a sealing process (after the zinc thermal spraying to a dry cleaning water, Zn (OH) ₂ as a sealing treatment by a water wash)

Sample E: Sealed with epoxy resin sealing on Sample C (sealed with double-fluid room temperature curing epoxy resin after zinc spraying).

Sample F: Thermal sprayed zinc aluminum alloy on carbon steel (alloy thickness 80㎛)

Sample G: the sample _{F Zn (OH) 2, Al} (OH) 3 sealing treatment (zinc after an aluminum alloy sprayed to a dry cleaning with water, sealing treatment with water, washed with _{Zn (OH) 2, Al (} OH) 3) a that

Sample H: Sample F with the same Si sealing as Sample B

Sample I: white gas pipe (galvanized steel pipe)

(Evaluation Example 4)

The following sample (60 mm x 50 mm x 3 mm thickness) was immersed in 200 ml of MEK, and the production | generation amount of the heavy powder when the immersion temperature was 35 degreeC was measured. Table 4 shows the measurement results.

Sample J: Tank iron plate (carbon steel)

Sample K: A film formed of carbon steel with zinc rich paint (manufactured by Kansai Paint Co., Ltd., trade name: SD Zinc 1500A).

Sample L: Carbon steel coated with epoxy resin (manufactured by Kansai Paint Co., Ltd., trade name: Million Clear).

In the table, the unit of the heavy amount is (wtppm).

As a result, it was confirmed that the production of heavy powders can be suppressed in samples K and L. However, for sample K, alcohols and ketones were detected in addition to the usual heavy powder after 1000 hours. Moreover, the elution component of the epoxy resin was detected in the epoxy resin coating. Therefore, they are not very suitable for the production equipment of MEK.

The deterioration of the methyl ethyl ketone at the time of purification or storage of methyl ethyl ketone can be prevented by the method for preventing the production of heavy content of methyl ethyl ketone of the present invention, a purification facility or a storage facility.

Claims (6)

A method for preventing the production of heavy content of methyl ethyl ketone using a dimerizing prevention material at least on the contact surface with methyl ethyl ketone in a purification plant or a storage plant. The method of claim 1, The dimerization prevention material is zinc, aluminum, zinc aluminum alloy, tin, stainless steel, fluorine resin, or polyolefin resin. The method of claim 2, The dimerization prevention material used for the said refining installation is the method of preventing the generation of heavy content of methyl ethyl ketone which is stainless steel. The method of claim 3, A method for preventing the production of heavy content of methyl ethyl ketone, wherein the purification equipment is a condenser for cooling methyl ethyl ketone and / or a receiver temporarily receiving. The method of claim 2, The dimerization prevention material used for the said storage installation is a zinc, aluminum, zinc aluminum alloy, or the method of preventing the formation of the heavy content of methyl ethyl ketone which is tin. A purification apparatus or storage facility for methyl ethyl ketone, wherein at least the contact surface with methyl ethyl ketone is made of a dimerization prevention material.

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