JP2002047226A - Method for separating and recovering phenol compound and hydrocarbon oil from mixture containing the components - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for separating and recovering a phenol compound and a hydrocarbon oil from a mixture containing the components, by which both the hydrocarbon oil and the phenol compound can efficiently be separated and discovered from the mixture containing the hydrocarbon oil and the phenol compound. SOLUTION: This method for separating and recovering the phenol compound and the hydrocarbon oil from the mixture containing the components comprises the combination of plural processes including (i) a process for adding and mixing an alcohol with a mixture containing the phenol compound and the hydrocarbon oil, bringing the mixture into contact with water to separate into a water phase comprising water, the alcohol, the phenol compound and the hydrocarbon oil associated with the phenol compound and an oil phase comprising the hydrocarbon oil and the alcohol associated with the phenol, and (ii) a process for bringing the water phase into contact with a liquid hydrocarbon to separate into an oil phase comprising the liquid hydrocarbon and the hydrocarbon oil and the water phase comprising the water, the alcohol and the phenol compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for separating and recovering a phenol and a hydrocarbon oil from a mixture containing these components.

[0002]

2. Description of the Related Art Coal liquefied oil obtained by liquefying coal contains phenols, that is, phenol and phenol derivatives such as phenol derivatives such as cresol and ethylphenol, in addition to hydrocarbon oil. In the case of using coal liquefied oil, it is necessary to separate them and extract them as hydrocarbon oils and phenols having the highest possible purity. Such mixtures of hydrocarbon oils and phenols can be found in other processes. For example, phenols are present in petroleum cracked products in addition to hydrocarbon oils, and it is necessary to separate hydrocarbon oils and phenols. Also, in the process of producing phenol, it is necessary to separate phenol from the treatment object containing phenol and the like in addition to hydrocarbon oil.

As a method for separating phenols from hydrocarbon oils containing phenols, the present inventors have previously proposed a separation method combining steps 1 to 6 shown in FIG. No. 11-253750). In this method, in particular, the alcohol mixed in the oil phase obtained from the step 2 can be separated by washing the water in the step 6, so that a highly pure hydrocarbon oil can be obtained.

[0004]

SUMMARY OF THE INVENTION The present invention is a further development and flight of these methods. In the present invention, a mixture containing a hydrocarbon oil and a phenol is used to obtain not only a hydrocarbon oil but also a phenol. It is an object of the present invention to provide a method for separating and recovering efficiently with purity.

[0005]

According to the present invention, the following inventions are provided. (1) In separating and recovering each of these components from a mixture containing phenols and hydrocarbon oil, a phenol and hydrocarbon oil are mixed from a mixture containing phenols and hydrocarbon oil characterized by combining the following steps: A method of separating and recovering hydrocarbon oil. (I) In a mixture containing phenols and hydrocarbon oil,
An alcohol is added and mixed, and then brought into contact with water to form an aqueous phase composed of water, alcohol, phenols and a hydrocarbon oil associated therewith, and an oil phase composed of a hydrocarbon oil and an alcohol associated therewith. (Ii) contacting the aqueous phase with a liquefied hydrocarbon under pressure to separate it into an oil phase composed of liquefied hydrocarbon and hydrocarbon oil and an aqueous phase composed of water, alcohol and phenols Step (iii) Returning the oil phase consisting of the liquefied hydrocarbon and the hydrocarbon oil under pressure to normal pressure, separating the liquefied hydrocarbon as a gaseous hydrocarbon, and pressurizing the gaseous hydrocarbon if necessary. A liquefied hydrocarbon, which is circulated and used in the step (ii), and the hydrocarbon oil is taken out of the system; (iv) the step (ii)
The water phase composed of water, alcohol and phenols is distilled to separate into a mixture composed of alcohol, water and phenols, and the alcohol is circulated to the above step (i), and the mixture is composed of water and phenols. A step of contacting the mixture with a phenol extractant to separate an oil phase composed of phenols and the phenol extractant and an aqueous phase composed of water,
(V) a step of distilling an oil phase composed of phenols and a phenol extractant to separate it into a phenol extractant and a phenol, recycling the phenol extractant in the step (iv), and removing the phenols from the system; (Vi) washing the oil phase of the hydrocarbon oil obtained in the step (i) with the aqueous phase of the water, and purifying and separating the hydrocarbon oil;

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION [Mixture to be Treated of the Present Invention] The mixture to be treated according to the present invention is a mixture of a hydrocarbon oil and a phenol. As such a mixture, for example, coal liquefied oil, coal tar oil, biomass liquefied oil, phenol-containing hydrocarbon oil such as waste plastic liquefied oil, a mixture of phenol and hydrocarbon oil obtained from the phenol production process. Can be mentioned.

[Hydrocarbon oil] Examples of the hydrocarbon oil include hydrocarbon oils composed of aliphatic hydrocarbons, aromatic hydrocarbons, alicyclic hydrocarbons and the like. The aliphatic hydrocarbon may be a gaseous hydrocarbon in addition to a liquid hydrocarbon at normal temperature. As aromatic hydrocarbons, in addition to aromatic compounds such as benzene, biphenyl, and diphenylmethane, condensed cyclic compounds such as naphthalene, anthracene, naphthacene, phenanthrene, and pyrene, and alkyl groups and the like are substituted on these hydrocarbons. And the like.

[Phenols] In the present invention, phenols refer to aromatic hydrocarbons having an OH group and mixtures thereof. Specifically, phenols and cresols (o-cresol, m-cresol, phenol substituted with an alkyl group such as p-cresol, catechol, pyrogallol, naphthol (α-naphthol,
phenols such as (β-naphthol) and mixtures thereof. The mixing ratio of the hydrocarbon oil and the phenol can be dealt with by changing the conditions of the separation operation described later, and therefore, any ratio may be used. Note that the hydrocarbon may contain a nitrogen-containing compound containing nitrogen or a sulfur-containing compound containing sulfur.

[Outline of the Process of the Present Invention] The outline of the process of the present invention will be described by taking as an example a case where a phenol-containing oil (hereinafter also referred to as a raw material oil) is used as a mixture to be treated. This process can be illustrated by a flow sheet as in FIG.

[Step (i): A raw oil is mixed with an alcohol and then brought into contact with water to form an aqueous phase composed of water, alcohol, phenols and a small amount of a hydrocarbon oil, and a hydrocarbon oil. Step of separating oil phase]

(A) Pretreatment of Phenols by Mixing with Alcohol In the method of the present invention, first, a raw material oil to be treated is contact-mixed with alcohol, and phenols contained therein are coordinated with alcohol. Preliminary treatment is performed so as to be easily extracted into water. As the alcohol, a monohydric aliphatic alcohol is used. Specific examples include methanol and ethanol. Among these, methanol is preferably used in consideration of easy handling such as not forming an azeotropic compound. The alcohol concentration is desirably high, but may contain water. The mixing ratio between the alcohol and the base oil may be appropriately determined depending on the amount of phenols contained in the base oil. A general mixing ratio is 1
The ratio is 0.2 to 1: 8, usually a mixing ratio of about equal volume. Usually, the alcohol is supplied in a liquid state and is uniformly mixed.

(B): Step of extracting phenols by contacting with water In the present invention, the following steps are obtained in steps (i) and (a):
By bringing a solution containing alcohol, phenol and hydrocarbon oil therein into contact with water, phenols and alcohol are taken out as an aqueous phase and hydrocarbon oil is taken out as an oil phase. That is, in this step, the phenol-alcohol component which is easily extracted into water by the addition of the alcohol is extracted with water, and the hydrocarbon is extracted as an oil phase.

Although most of the hydrocarbon oil is shifted to the oil phase by the extraction operation with water in this step, a small amount of the hydrocarbon oil is still mixed with the water phase, and The phase contains a small amount of hydrocarbon oil in addition to alcohol and phenol.

The amount of water to be added is arbitrarily determined within a range where alcohol and phenols can be extracted, but a general mixing ratio is from 1 to 0.2 to the total amount of the feed oil and the alcohol.
One to eight. The extraction temperature can be appropriately selected and set within a temperature range in which water, alcohol, and phenol can be mixed.

Step (i) may be a single step and may be an extraction tower operation.

The aqueous phase consisting of water, alcohol, phenols and hydrocarbon oil mixed therewith is sent to the next hydrocarbon oil separation step. On the other hand, the oil phase composed of the hydrocarbon oil is sent to the step (vi) of separating alcohol accompanying the hydrocarbon oil by washing with water.

[Step (ii): The above aqueous phase is brought into contact with a liquefied hydrocarbon under pressure to separate it into an oil phase composed of liquefied hydrocarbon and hydrocarbon oil and an aqueous phase composed of water, alcohol and phenols. This step is the same as the step (i)
An object of the present invention is to separate and remove hydrocarbon oil components from an aqueous phase composed of water, alcohol, phenols and hydrocarbon oil mixed therein. As a means for that, in the present invention,
The aqueous phase is brought into contact with a liquefied hydrocarbon under pressure, and an extraction method is employed in which hydrocarbon oil mixed in the aqueous phase is extracted as an oil phase.

As the liquid hydrocarbon, any hydrocarbon can be used as long as it is easily liquefied by pressurization with a gas at normal temperature and normal pressure. The liquefied hydrocarbon preferably used in the present invention is liquefied propane, liquefied butane and the like. By the extraction operation using the liquefied hydrocarbon, the hydrocarbon oil mixed in the aqueous phase component is transferred to the oil phase. Extraction pressure is several kg / cm2-10
It is preferably about kg / cm2, and the extraction temperature at room temperature is sufficient.

The oil phase in this step is converted into the following step (iii)
To the liquefied hydrocarbon recovery process.

Further, the aqueous phase from which the hydrocarbon oil has been removed, consisting of water, alcohol and phenol, is sent to these separation steps (iv).

[Step (iii): The oil phase comprising the liquefied hydrocarbon and the hydrocarbon oil under pressure is returned to normal pressure, and the liquefied hydrocarbon is separated as a gaseous hydrocarbon. Pressurizing and circulating the liquefied hydrocarbon as a liquefied hydrocarbon in the step (ii) and removing the hydrocarbon oil out of the system] In the present invention, the oil phase obtained in the step (iii) is then added to the oil phase. Separate into liquefied hydrocarbons and hydrocarbon oils contained. This step is performed by a simple operation of simply returning the oil phase under pressure to normal pressure.
In other words, the liquefied hydrocarbon, which is the extractant, is vaporized by returning to normal pressure, and becomes a gaseous hydrocarbon.
It is easily gas-liquid separated from liquid hydrocarbon oil.

The hydrocarbons which are in a gaseous state and separated from the oil phase are recovered, pressurized if necessary, and can be recycled as liquefied hydrocarbons in the step (ii).
Further, it may be recycled to the feedstock oil of the step (i).

The hydrocarbon oil in the oil phase from which the liquefied hydrocarbon has been removed is recovered and taken out of the system.

[Step (iv): The aqueous phase from which the hydrocarbon oil has been separated is distilled to separate it into a mixture of alcohol, water and phenols, and the alcohol is circulated to the step (i). And contacting a mixture comprising water and phenols with a phenol extractant to separate the mixture into an oil phase comprising phenols and an extractant and an aqueous phase comprising water. In the present invention, then, an alcohol, water, By purifying the aqueous phase obtained in the above step (ii), comprising phenol and phenols, a pure alcohol is separated and taken out. In this step, a distillation operation is used as a separation and purification means.

By this distillation operation, alcohol as a low-boiling component is taken out as a top distillate, and a component consisting of phenols and water is taken out as a bottom component. An additional portion of the overhead fraction alcohol is added as necessary and used as the alcohol in step (i).

The bottom component consisting of phenols and water is separated into phenols and water. The separation of phenols and water is performed by extracting and separating phenols with a phenol extractant (hereinafter also referred to as a simple extractant). As the extractant, any solvent that can extract phenols can be used. Generally, an aromatic hydrocarbon is used in consideration of ease of handling, economy, and the like.

Examples of the aromatic hydrocarbon include hydrocarbons such as benzene, toluene and xylene, and these are used alone or as a mixture of two or more. When used as a mixed solvent, it is desirable to combine hydrocarbons having as close boiling points as possible, considering that the subsequent step of purifying the extractant is a distillation operation.

It is preferable to carry out the extraction step in multiple stages and to carry out a multistage extraction in order to obtain a high-purity product. The number of stages can be appropriately set according to the purpose. The use ratio of the phenols and water to the extractant is 1: 0.2 to 1: 1.
It is four.

[Step (v): The oil phase composed of phenols and the extractant is distilled to separate the extractant and the phenol, and the extractant is recycled to the step (iv) to remove the phenols from the system. In the present invention, the mixture of the phenol and the extractant obtained by the extraction operation in the previous step is then separated into the phenol and the extractant. A distillation operation is used for the separation operation. The separated phenols are
It is taken out of the system. The extractant is circulated and used as the extractant in the previous step. When used as an extractant in the previous process,
If necessary, the same type of solvent is additionally replenished.

[Step (vi): The oil phase consisting of the hydrocarbon oil and the alcohol accompanying the oil obtained in the step (i) is washed with the aqueous phase consisting of the water to remove the hydrocarbon oil. Purification and Separation Step] In the present invention,
Water is added as necessary to the aqueous phase of water separated from the step (iv), and the oil comprising the hydrocarbon oil and the alcohol accompanying the oil obtained in the step (i) is obtained. Contact with phase. Specifically, by washing with water, the alcohol accompanying the hydrocarbon oil is separated and removed.
The washed hydrocarbon oil is high in purity, free of impurities, phenols and alcohols,
Removed as the desired product. The ratio of hydrocarbon oil to water is 1: 0.2 to 1: 8. The water used for washing is circulated and used as the water in the step (i).

[0031]

The present invention relates to a method for separating and recovering these components from a mixture containing a phenol and a hydrocarbon oil, and combines the above steps (i) to (vi). It has a remarkable effect. (1) A step of contacting an aqueous phase comprising alcohol, water, phenols and a hydrocarbon oil accompanying the same obtained in step (i) with a liquefied hydrocarbon to remove hydrocarbon oil contained therein ( adopting ii), and subjecting the mixture of alcohol, water and phenols, from which the hydrocarbon oil has been removed, to a purification / separation step comprising a combination of steps (iv) and (v). Thereby, phenols having high purity can be efficiently recovered. (2) Since the step (vi) of bringing the oil phase obtained from the step (i), consisting of the hydrocarbon oil and the alcohol accompanying the hydrocarbon oil, into contact with water is employed, the alcohol-free high-purity hydrocarbon is used. The oil can be efficiently recovered. (3) Since the liquefied hydrocarbon is used as the extraction solvent when separating the hydrocarbon oil contained in the water phase of the above (i), the oil phase composed of the liquefied hydrocarbon and the hydrocarbon oil after the extraction is used. Simple operation of simply returning to normal pressure (step (iii))
Can separate liquefied hydrocarbons and hydrocarbon oils,
Moreover, the hydrocarbon separated by vaporization can be liquefied by pressurizing the hydrocarbon if necessary, and can be reused in the step (ii) (step (iii)). Therefore, as compared with a case where a liquid hydrocarbon such as heptane or the like is used at room temperature and pressure as the extraction solvent, (a) a large distillation column is not required for the recovery, and (b) reuse. (C) energy cost for collecting and reusing the solvent can be greatly reduced. (4) The alcohol used in step (i) is the same as step (iv)
Can be recycled to the step (i). Similarly, the water used in the step (i) can be used in the step (vi) for refining the hydrocarbon oil by being subjected to the step (iv), and can be recycled to the step (i) if necessary. Also,
The phenol extractant used in step (iv) can also be recycled to step (iv) by subjecting it to step (v).
Then, as described in the above (c), the liquefied hydrocarbon used in the step (ii) can also be recycled to the step (ii) by being subjected to the step (iii). As described above, in the present invention, since all of water, alcohol, liquefied hydrocarbon, and phenol extractant are used in circulation, the entire system can be performed in a closed system without being discharged out of the system.

[0032]

EXAMPLES The method of the present invention will be described below with reference to examples. The present invention is not limited by this embodiment. Example 1 A hydrocarbon oil having the following properties was treated. [Coal liquefied oil] Coal liquefied oil component Neutral oil (a hydrocarbon, a mixture of aromatic hydrocarbon, aliphatic hydrocarbon and alicyclic hydrocarbon) 736 Phenol 48 Phenols (excluding phenol) 148 Other components 68 Total 1000 (in terms of weight) (a) Step (i) To 1000 parts by weight of the hydrocarbon oil, 68 parts by weight of the recovered oil were added, and 1008 parts by weight of methanol were mixed. The mixture was extracted by bringing it into contact with 1103 parts by weight of water, and 2312 parts by weight of a water-methanol phase and 882 parts by weight of an oil phase were taken out. (B) Step (ii) The water-methanol phase is brought into contact with 1504 parts by weight of liquefied butane under pressure to obtain 1570 parts by weight of an oil phase composed of liquefied butane and hydrocarbon oil, and water, methanol and phenols. 2246 parts by weight of the resulting water-methanol phase were taken out. (C) Step (iii) The oil phase composed of liquefied butane and hydrocarbon oil was returned to normal pressure, and 1502 parts by weight of liquefied butane and 68 parts by weight of hydrocarbon oil were taken out as recovered oil. This liquefied butane is in shortage 2
A part by weight was added and pressurized to obtain liquefied butane, which was recycled in step (ii). The recovered oil was added to the feedstock in step (i). (D) Step (iv) The aqueous phase obtained in the step (ii) was distilled to take out 1008 parts by weight of a top made of methanol and 1238 parts by weight of a bottom made of water, phenol and phenols. The methanol overhead was recycled to step (i), supplementing the shortage of 14 parts by weight. Since 124 parts by weight of the supersaturated phenol separated from the aqueous phase, the bottom was recovered.
1114 parts by weight of an aqueous phase containing phenols were brought into contact with 951 parts by weight of toluene using a three-stage countercurrent extraction device to recover 1019 parts by weight of a mixture comprising phenols and toluene and 1046 parts by weight of an aqueous phase. (E) Step (v) The mixture of toluene, phenol and phenols in the preceding step was introduced into a distillation column and separated into toluene, phenol and phenols. Toluene was added in an insufficient amount of 2 parts by weight and recycled as an extractant in step (iv). (F) Step (vi) The aqueous phase of the step (v) was taken out, 21 parts by weight of the insufficient water was added, the oil phase obtained in the step (i) was washed, and the hydrocarbon oil was taken out. The water used for washing was circulated and used as water in step (i). The properties of the obtained refined hydrocarbon oil were as follows. Neutral oil (aromatic hydrocarbon, aliphatic hydrocarbon and alicyclic hydrocarbon) 736 Phenol 5 Phenols 49 Other components 49 (subtotal) 839 Methanol 1 Water 2 Toluene 2 Total 834 The properties of the crude phenol obtained are as follows: It was as follows. Neutral oil 0 Phenol 43 Phenols 109 Other 10 (subtotal) 162 Methanol 13 Water 19 Total 194 The added amount of the added solvent was as follows. Methanol 14 water 20 toluene 1

[Brief description of the drawings]

FIG. 1 is a flow sheet illustrating the method of the present invention.

FIG. 2 is a flow sheet showing a conventional method.

[Explanation of symbols]

(I): a step of separating the feedstock oil into an aqueous phase composed of water, alcohol, phenols and a hydrocarbon oil associated therewith, and an oil phase composed of the hydrocarbon oil and an alcohol associated therewith (ii) ): A step of bringing the above aqueous phase into contact with a liquefied hydrocarbon under pressure to separate it into an oil phase composed of the liquefied hydrocarbon and hydrocarbon oil and an aqueous phase composed of water, alcohol and phenols; (Iv) separating an oil phase composed of liquefied hydrocarbons and hydrocarbon oil into liquefied hydrocarbons as gaseous hydrocarbons, circulating the liquefied hydrocarbons in step (ii), and removing the hydrocarbon oil out of the system; : Separating the aqueous phase of the step (ii) into a mixture of alcohol, water and phenols, circulating the alcohol to the step (i), and extracting the mixture of water and phenols with a phenol extractant Contact with Let me
Separating the oil phase consisting of phenols and phenol extractant and the aqueous phase consisting of water (v): separating the oil phase consisting of phenols and phenol extractant into phenol extractant and phenol, Is recycled to the step (iv) and the phenols are taken out of the system. (Vi): The oil phase consisting of the hydrocarbon oil obtained in the step (i) is washed with the aqueous phase. Process of refining and separating hydrocarbon oil

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C07C 15/20 C07C 15/20 37/72 37/72 37/74 37/74 39/14 39/14 C10G 21/02 C10G 21/02 53/04 53/04 (72) Inventor Koji Ukegawa 16-3 Onogawa, Tsukuba, Ibaraki Pref. National Institute of Advanced Industrial Science and Technology (72) Inventor Ikuo Saito Onogawa, Tsukuba, Ibaraki 16-3 F-term in the National Institute of Advanced Industrial Science and Technology (AIST) 4H006 AA02 AD11 AD16 BB14 BB31 BC52 BD60 FC52 FC54 FE13 4H029 DA01 DA05

Claims (1)

[Claims] (1) In separating and recovering each of these components from a mixture containing a phenol and a hydrocarbon oil,
A method for separating and recovering a phenol and a hydrocarbon oil from a mixture containing a phenol and a hydrocarbon oil, characterized by combining the following steps. (I) In a mixture containing phenols and hydrocarbon oil,
An alcohol is added and mixed, and then brought into contact with water to form an aqueous phase composed of water, alcohol, phenols and a hydrocarbon oil associated therewith, and an oil phase composed of a hydrocarbon oil and an alcohol associated therewith. (Ii) contacting the aqueous phase with a liquefied hydrocarbon under pressure to separate it into an oil phase composed of liquefied hydrocarbon and hydrocarbon oil and an aqueous phase composed of water, alcohol and phenols Step (iii) Returning the oil phase consisting of the liquefied hydrocarbon and the hydrocarbon oil under pressure to normal pressure, separating the liquefied hydrocarbon as a gaseous hydrocarbon, and pressurizing the gaseous hydrocarbon if necessary. A liquefied hydrocarbon, which is circulated and used in the step (ii), and the hydrocarbon oil is taken out of the system; (iv) the step (ii)
The water phase composed of water, alcohol and phenols is distilled to separate into a mixture composed of alcohol, water and phenols, and the alcohol is circulated to the above step (i), and the mixture is composed of water and phenols. A step of contacting the mixture with a phenol extractant to separate an oil phase composed of phenols and the phenol extractant and an aqueous phase composed of water,
(V) a step of distilling an oil phase composed of phenols and a phenol extractant to separate it into a phenol extractant and a phenol, recycling the phenol extractant in the step (iv), and removing the phenols from the system; (Vi) washing the oil phase of the hydrocarbon oil obtained in the step (i) with the aqueous phase of the water, and purifying and separating the hydrocarbon oil;