JPH0583530B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method for recovering phenol and its derivatives from oil containing phenol and its derivatives, and in particular, a method for recovering phenol and its derivatives from hydrocarbon oil with a low content of oxygen compounds. The present invention relates to a method for recovering phenol and its derivatives with high selectivity.

<Prior art> A method for separating phenol and its derivatives from an oil containing them is as follows: 1. Treat with an alkaline aqueous solution such as sodium hydroxide to generate an alkali salt, and heat and evaporate the water to obtain an alkali salt. A method for obtaining the target compound by neutralizing the salt with sulfuric acid (Coal Tar, vol. 4, 135 (1952)), 2
Examples include solvent extraction methods using hydrocarbon solvents such as benzene and toluene (Coal Tar, vol. 8, (1956)). However, method 1 requires an amount of alkali and acid for neutralization commensurate with the phenolic hydroxyl group, and it is difficult to recover these economically, and method 2 has a low extraction rate and requires several stages of extraction. Both methods have the disadvantage of increasing the cost of recovering the target compound, such as the need for a step.

<Object of the Invention> The present invention aims to solve these problems in the prior art and recover phenol derivatives such as phenol and cresol only by using alcohol and water.

<Structure of the Invention> The present inventor has discovered that when alcohol is added to oil containing phenol and its derivatives and the oil is brought into contact with water, the phenol and its derivatives are extracted into the aqueous layer together with the alcohol, and the present invention has been accomplished based on this finding. It came to this.

According to this method, phenol and its derivatives can be separated from oil containing phenol and its derivatives regardless of the high or low concentration of oxygen compounds, and phenol, cresol, ethylphenol, etc. can be separated with a selectivity of 95% or more. can.

The present invention will be explained in detail below.

Hydrocarbon oil such as liquefied coal oil contains phenol, cresol, ethylphenol, and the like. When alcohol is added to this hydrocarbon oil, phenol or its derivatives and alcohol form hydrogen bonds. In this case, the amount of alcohol added is 0.5 to 6 times that of the hydrocarbon oil. When water is then added to this mixture, alcohol is extracted into the aqueous layer, and at the same time, phenols and their derivatives that form hydrogen bonds with alcohol are also extracted into the aqueous layer. As a result, it separates into a water-alcohol layer rich in phenol and its derivatives and an oil layer. in this case,
The amount of water added is 0.25 to 12 times the amount of hydrocarbon oil.
Use double the amount. The alcohol can be easily recovered from the water-alcohol layer by distillation and reused as additive alcohol. Furthermore, by recovering the alcohol, phenol and its derivatives become oily substances, which are separated into two layers: water and oily substances, and the water can be reused as water for addition.

When the amount of alcohol added is increased, the extraction rate of phenol and its derivatives is high. When 5 volumes of methanol and 1 volume of water are used for 1 volume of hydrocarbon oil, the recovery rate is 72% in one extraction operation. Phenol and its derivatives containing about 100% were obtained. Further, the extraction temperature is 0°C or higher and 100°C or lower, preferably at room temperature and normal pressure.

FIG. 1 shows a flowchart of an embodiment of the method for recovering phenol and its derivatives according to the present invention.

<Examples> The present invention will be specifically described below using examples.

Example 1 Phenol 5.7%, o-cresol 1.7%, m,
To 1 volume of Battle River coal liquefied oil naphtha fraction containing 6.2% p-cresol and 0.8% m,p-ethylphenol, 6 volumes of methanol was added and mixed, and then 1 volume of water was added and mixed. Phenol, cresol, and ethylphenol were extracted into the water-methanol layer. The extraction rate is phenol 57.9%, o-cresol 62.1%, m, p-cresol 77.7%,
m, p-ethylphenol 80.8%, selectivity phenol 32.0%, o-cresol 9.9%, m, p-
Cresol 44.7%, m,p-ethylphenol
7.9%, total 94.5%.

Example 2 Phenol 5.7%, o-cresol 1.7%, m,
To 1 volume of Battle River coal liquefied oil naphtha fraction containing 6.2% p-cresol and 0.8% m,p-ethylphenol, 6 volumes of methanol was added and mixed, and then 12 volumes of water were added and mixed. Phenol, cresol, and ethylphenol were extracted into the water-methanol layer. The extraction rate is approximately 100% for phenol, o-cresol, m, p-cresol, and m, p-ethylphenol, and the selectivity is 33.5% for phenol.
o-cresol 9.6%, m, p-cresol 43.4
%, m, p-ethylphenol 7.0%, total 93.4%
It was hot.

<Effects of the Invention> According to the method of the present invention, phenol derivatives such as phenol and cresol can be economically and highly concentrated from oil containing phenol or its derivatives by a simple method using an inexpensive solvent at room temperature and normal pressure. Can be separated.

The recovered phenol and its derivatives can be further purified by combining other concentration and purification methods.
It can be used as a high-purity chemical raw material.

[Brief explanation of the drawing]

FIG. 1 is a flowchart illustrating the method of the present invention.

Claims (1)

[Claims] 1. A recovery method characterized by adding alcohol to an oil containing phenol and its derivatives, and then extracting phenol and its derivatives by bringing the mixture into contact with water.