KR100366892B1 - Catalyst for preparing 2,4-ditertiary butylphenol and method for preparing 2,4-ditertiary butylphenol using the same - Google Patents

Abstract

PURPOSE: Provided are a catalyst for preparing 2,4-ditertiary butylphenol from phenol and isobutylene, and a method for preparing 2,4-ditertiary butylphenol using the same. CONSTITUTION: In a method for preparing 2,4-ditertiary butylphenol by addition reaction of isobutylene to phenol in the presence of a catalyst, the catalyst is fabricated by calcining activated clay including 1 to 40 wt.% of γ-aluminum hydroxide or amorphous silica, wherein the γ-aluminum hydroxide is pseudo-boehmite; the amorphous silica is colloid silica; and the phenol is phenol compounds selected from 2-tertiary butyl phenol or 4-tertiary butyl phenol.

Description

Catalyst for producing 2,4-dibutylbutylphenol and Method for producing 2,4-dibutylbutylphenol using the catalyst

The present invention provides a catalyst for the production of 2,4-dibutylbutyl phenol substituted with a tertiary butyl group at 2,4-position from phenol and isobutylene, and to prepare 2,4-dibutylbutylphenol using the catalyst. It is about a method. 2,4-Dibutylbutylphenol (hereinafter referred to as 2,4-DTBP) is a material which is very usefully used industrially as a raw material of antioxidant.

In the known methods for producing 2,4-DTBP, isobutylene is reacted with phenol in the presence of an acid catalyst, and as a catalyst, sulfuric acid or phosphoric acid (Spain 835,794), halogen-supported alumina (US Pat. No. 4,275,249) ), Lithium-supported alumina (US Pat. No. 4,260,833), aluminum phenoxide (JP-A-63-150333) and a catalyst in which aluminum phenoxide is bound to a polymer resin (US Pat. No. 4,628,127), or activated white earth Acid clay (Japanese Patent Laid-Open No. 63-159334) and the like are used.

However, when sulfuric acid or phosphoric acid is used as a catalyst, a lot of isobutylene oligomers are generated, which lowers the effective utilization rate of isobutylene, necessitates a neutralization and washing process of the catalyst, and causes a large amount of pollution caused by waste water containing phenol Follow.

In the case of using a halogen-supported alumina catalyst, the oligomer formation of isobutylene is suppressed, but the catalyst cost is high and the energy consumption is high because the activity of the catalyst is relatively low and the reaction temperature is high.

Aluminum phenoxide catalyst is mainly used for the production of 2,6-dibutylbutyl phenol (hereinafter referred to as 2,6-DTBP). Depending on the reaction conditions, 2,4-DTBP can also be produced, but the yield is low and is produced together. Due to the large amount of 2,6-DTBP, separation and purification is difficult. In the case of a catalyst in which aluminum phenoxide is bonded to the polymer resin, the yield is high, but the amount of isobutylene and the catalyst is too high.

Activated clays such as acidic clays have excellent reaction activity and are advantageous over other catalysts in the preparation of 2,4-DTBP, and are easy to separate and remove the catalysts upon product recovery after the reaction is completed, and the separated catalysts can be recycled. .

However, since activated clay is generally in the form of a powder, it is necessary to form a catalyst for use in a fixed bed catalytic reactor, and the formation of the catalyst requires maintenance of catalytic activity as well as excellent mechanical strength.

The present invention is to add 2,4-DTBP from isobutylene and phenol using not only a batch reactor but also a fixed bed reactor by adding a new component to the activated clay to increase the mechanical strength during catalyst formation as well as the reaction activity of the catalyst. It is to provide a method of manufacturing efficiently.

The catalyst used in the present invention is excellent in reaction activity and selectivity, and is particularly advantageous compared to other known catalysts when alkylating the 2,4-position of phenol with isobutylene. It can be used in a fixed bed reactor for the purpose and can provide very useful advantages industrially.

In the present invention, the catalyst was prepared by uniformly mixing the aqueous solution of the component to be added with activated clay and then extruding to make pellets and calcining. As the component to be added, amorphous silica such as pseudoboehmite or colloidal silica, which is a kind of r-type aluminum hydroxide mineral, is suitable and can be used by using a commercially available product or by directly preparing it. The content of the additive component is suitably 1 to 40% by weight, preferably 5 to 35% by weight, based on the total amount of the catalyst.

The catalyst production method of the present invention is as follows. Activated clay, additives and water are mixed to make a dough. The dough is mixed uniformly for a certain time and then extruded into pellets, which are dried and calcined at a temperature of 250 ° C. or higher. Colloidal silica may be commercially available products or those prepared from ethyl orthosilicate.

An important point in the preparation of the catalyst is the moisture content and the particle size of the catalyst and the added component. The amount of water required for the preparation of the catalyst depends on the particle size of activated clay and aluminum content, and the particle size of activated clay is usually smaller than the particle size of the component to which it is added and has a variety of sizes. Is advantageous in

In this invention, as a phenol which is a raw material, the phenol mixture etc. which contain pure phenol, 2- or 4- tert-butyl phenol, 2,4,6- tributylbutyl phenol, etc. are used. As isobutylene, butylene gas containing pure isobutylene or isobutylene is used.

2,4-DTBP is prepared in a batch or continuous process from isobutylene and phenol in the presence of the catalyst of the present invention. The batch production method is as follows.

Pellets or powdered catalyst in the form of powder is 0.1 to 20% by weight, preferably 0.2 to 10% by weight of phenol mixed with agitation while stirring, the temperature 60-220 ℃, preferably 90-160 ℃, The pressure is injected with isobutylene under conditions of 1 to 300 kg / cm 2, preferably 1 to 10 kg / cm 2, and the reaction is usually performed for 20 minutes to 10 hours, preferably 30 minutes to 6 hours. As for the usage ratio of phenol and isobutylene, 1.2-3 mol is normally used with respect to 1 mol of phenol, Preferably 1.5-2.5 mol is used.

The continuous production method of 2,4-DTBP is as follows. A constant volume of catalyst pellets is charged into a cylindrical stainless steel reactor and continuously passed through a mixture of phenol and isobutylene while maintaining the catalyst bed at a constant temperature. The reaction temperature is 60-220 ° C., preferably 90-180 ° C., The pressure is 1 to 50 kg / cm 2, preferably 3 to 30 kg / cm 2. As for the usage ratio of phenol and isobutylene, 1.2-3 mol is normally used with respect to 1 mol of phenols, Preferably 1,5-2.5 mol is used.

The liquid hourly space velocity (hereinafter referred to as LHSV) passing through the catalyst volume per unit time is 0.1 to 10 hr ⁻¹ , preferably 0.3 to 5 hr ⁻¹ .

The present invention will be described in detail with reference to the following Examples. However, the present invention is not limited to the examples.

Example 1

24g of activated clay (from Engelhard, 10% by weight of water) and 8g of pseudoboehmite (75% by weight of water) are mixed with 13g of water to make a dough. Make pellets The pellet was dried in air for at least 10 hours and then calcined in air at 450 ° C. for 4 hours to prepare a catalyst.

A reaction experiment was conducted to prepare 2,4-DTBP from phenol and isobutylene using the catalyst prepared by the above method. 10 ml of catalyst was filled in a cylindrical stainless steel reactor having an inner diameter of l / 2 inch and the catalyst layer was maintained at 120 ° C. under a reaction pressure of 25 kg / cm 2, LHSV = 1.0hr ⁻¹ , and isobutylene / phenol = 2.0. The reaction experiment was conducted while continuously supplying isobutylene and phenol to the catalyst layer. Six hours after the start of the reaction, the reaction product was collected, and the composition of the reaction product was analyzed using gas chromatography. The results are shown in Table 1 below. As a result of measuring the mechanical strength of the prepared catalyst, the side crush strength was 3.9 kg / mm.

Example 2

A catalyst preparation and reaction experiment were carried out in the same manner as in Example 1, except that 8 g of amorphous silica (water content of 75 wt%) was used as the additive component. Mechanical strength measurement of the prepared catalyst, the grinding strength is 4.0kg / mm.

Example 3

A catalyst preparation and reaction experiment were carried out in the same manner as in Example 1, except that 19 g of water was used without using an additive component. As a result of measuring the mechanical strength of the prepared catalyst, the grinding strength is 2.7 kg / mm.

Table 1. Continuous reaction test results

Example 4

100 g of phenol and 1 g of a powder obtained by grinding the catalyst prepared in Example 1 into 50 to 100 mesh were put into a 600 ml SUS high-pressure reactor, and the temperature was raised to 120 ° C. while stirring. The reaction was continued by feeding. Samples were taken during the reaction and the composition of the reaction product was analyzed using gas chromatography. After a certain period of time, the stirring was stopped, the reactor was cooled, the unreacted isobutylene was released, and the catalyst was separated by filtration to obtain a reaction product. The composition of the reaction product is shown in Table 2.

Example 5

A batch reaction experiment was conducted in the same manner as in Example 4 except that the catalyst prepared in Example 2 was used.

Example 6

A batch reaction experiment was conducted in the same manner as in Example 4 except that the catalyst prepared in Example 3 was used.

Table 2. Batch Reaction Experiment Results

Claims (4)

In the catalyst for producing 2.4-dibutylbutyl phenol, which is based on phenol and isobutylene, 2.4-dibutyl butyl obtained by adding 1-40 wt% of r-aluminum hydroxide or amorphous silica to activated clay in activated clay. Phenol production catalyst. The catalyst for producing 2,4-dibutylbutylphenol according to claim 1, wherein the r-aluminum hydroxide is pseudo-boehmite and the amorphous silica is a colloidal silica. In the method for producing 2.4-di-butylbutylphenol by adding isobutylene to phenol in the presence of a catalyst, calcining activated clay containing 1 to 40% by weight of r-aluminum hydroxide or amorphous silica, based on the amount of activated clay, Process for the preparation of 2,4-dibutylbutylphenol using the prepared catalyst. 4. The method for producing 2,4-dibutylbutylphenol according to claim 3, wherein the phenol is a phenol mixture containing 2-tertiarybutylphenol or 4-tert-butylbutylphenol and isobutylene is mixed with butylene gas. .