JPS6034938B2 - Method for producing ethylene glycol monotertiary butyl ether - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing ethylene glycol monotarsia IJ-butyl ether.

Ethylene glycol monotertiary butyl ether is used as a solvent, dispersant, and in paints, inks, and other fields.
It is a useful substance with excellent performance as a diluent. This ethylene glycol monotertiary butyl ether can be produced using isobutylene and ethylene glycol as raw materials, and various acid catalysts are effective in this production. In particular, strongly acidic intestinal ion exchange resin catalysts have advantages such as high activity, no equipment corrosion or environmental pollution due to waste catalysts unlike potic acids, and easy separation from products. It is already known from US Pat. No. 3,317,483 that ethylene glycol monotertiary butyl ether is produced from isobutylene and ethylene glycol using a strongly acidic cation exchange resin as a catalyst. A common reaction method is to produce ethylene glycol monotertiary butyl ether by placing ethylene glycol, isobutylene, and an ion exchange resin in a pressure-resistant container equipped with an Azusa apparatus and stirring the mixture. Ethylene glycol monotertiary butyl ether can also be produced using a so-called fixed bed flow reactor in which ethylene glycol and isobutylene are fed into a reaction tube filled with an ion-exchanged resin. Compared to the former so-called rope-and-Western reaction method, the fixed bed flow reaction method generally has simpler and cheaper reaction equipment, no crushing of catalyst particles by hawking, and easier separation of the catalyst and reaction products. It has features that are advantageous for industrial implementation, such as being suitable for continuous operation. However, in both the rope reaction method and the fixed bed flow reaction method, in addition to the target ethylene glycol monotertiary butyl ether, by-products such as diisobutylene and ethylene glycol ditertiary butyl ether are unavoidable. ,
In particular, when a fixed-bed flow reaction method is adopted, a large amount of by-products such as ethylene glycol di-tert-butyl ether and diisobutylene are produced, making it impossible to obtain the desired ethylene glycol mono-tert-butyl ether in high yield. Met. That is, according to the studies of the present inventors, in the reaction of reacting ethylene glycol and isobutylene in a flow system to obtain ethylene glycol monotertiary butyl ether, under conditions where the conversion rate is low, for example, when the liquid hourly space velocity value of the raw material is Under relatively high conditions, although the selectivity of the target ethylene glycol monotertiary butyl ether is high, the conversion rate is low, resulting in a low yield of the target monoether, and in order to increase the conversion rate, the liquid hourly space velocity is low. If it is lowered, many by-products will be produced and the selectivity and yield of the desired monoether will be lowered. In order to overcome this problem, we investigated various factors and found that by increasing the linear velocity of the reaction raw material in the catalyst bed, that is, the flow rate of the reaction raw material per cross-sectional area of the catalyst bed packed in a fixed bed flow reactor. The present invention was completed by completely unexpectedly discovering that the amount of by-products produced can be suppressed to a large extent. It is thought that the by-product of diisobutylene can be suppressed by improving the contact between the reaction raw materials, but the production of ethylene glycol mono-tert-butyl ether is suppressed, and the formation of ethylene glycol mono-tert-butyl ether, which has a similar chemical structure, is suppressed. The increased selectivity for ether was completely unexpected. That is, the gist of the present invention is a method for producing ethylene glycol monotersia IJ-butyl ether by reacting ethylene glycol and isobutylene in the presence of a strongly acidic cation exchange resin as a catalyst, using a fixed bed flow reactor. and a method for producing ethylene glycol monotertiary butyl ether, characterized in that the reaction is carried out at a linear velocity of the raw material passing through the catalyst bed (a value calculated as a liquid state) of 120 c per hour or more. The linear velocity of the raw material according to the present invention is expressed by the following formula. Raw material linear velocity = F/S (skin/
hr) where F is the feed rate of all feedstocks to the reactor, including ethylene glycol, isobutylene reaction raw materials, reaction product recycle and diluent, if used, in liquid state under pressure at room temperature. It is a value expressed in volume C/hr, and S is a value expressed in c, which is the cross-sectional area of the catalyst bed in a direction perpendicular to the raw material passing direction.

If S is not constant throughout the reactor, it refers to its maximum value. By the way, the raw material liquid space velocity LHSV is F/
V(hrl). Here, V is the volume of the catalyst bed packed in the reactor. As understood from these definitions, the raw material linear velocity and the raw material liquid space velocity are independent values. In the method of the present invention, the raw material linear velocity must be 120 k/hr or more.

If it is lower than this value, the amount of ethylene glycol di-tertiary butyl ether by-product will increase significantly, and this problem will be especially noticeable when the conversion rate of the reaction raw material is high. The preferable conditions for the raw material linear velocity are 130 to 2000 k/hr, especially 1
It is 50~loo0ky/hr. At a constant liquid hourly space velocity, methods for increasing the linear velocity include, for example, increasing the height of the catalyst bed, and increasing the linear velocity of part of the product to 12
A method may be used in which the amount is recycled to the reactor in an amount of 0 skin/hr or more, or a method in which a solvent or other inert substance is distributed to the reactor together with the raw materials. Why does increasing the linear velocity suppress the by-product of ethylene glycol di-tert-butyl ether and increase the production of the desired ethylene glycol mono-tert-butyl ether?
The reason is unknown. Examples of the strongly acidic cation exchange resin used as a catalyst in the method of the present invention include styrene-divinylbenzene having a sulfonic acid group such as a styrene sulfonic acid type enteric ion exchange resin and a phenolsulfonic acid type cation exchange resin. Items that exhibit strong acidity such as polymers (
Commercially available products include, for example, Amberlyst 1U, Amberlyte IR-118, and Dowax 50W-1x12.

) can be given. Further, as for the physical structure of these ion-exchanged resins, either gel type or macroporous type can be used. Isoptylene as a reaction raw material may be reacted alone with ethylene glycol, or more economically, C4 fractions (isobutylene, butane and - butylene mixtures) can be used. When using a C4 fraction, n-butylene reacts with ethylene glycol to form ethylene glycol monosecondary butyl ether, but the amount is usually very small.
Stay in small amounts. The relative amounts of raw isobutylene and ethylene glycol affect the conversion rate of isobutylene and the selectivity of ethylene glycol monotertiary butyl ether. When the molar ratio of ethylene glycol to isobutylene is large, the conversion rate of isoptylene is high, but the selectivity of ethylene glycol monotertiary butyl ether is high. On the other hand, when the molar ratio is small, the conversion rate of isobutylene is slow and the selectivity of ethylene glycol monotertiary methyl ether is low. The molar ratio of ethylene glycol to isobutylene is preferably in the range of 0.1 to 10, more preferably in the range of 0.5 to 5. Next, the liquid hourly space velocity (LHSV) of the reaction raw material is a factor that directly controls the conversion rate of isobutylene, and should be controlled to obtain the desired conversion rate of isobutylene. Normal LHS
A suitable V value is about 0.1 to 2 r-1, particularly 0.5 to r-1. The reaction temperature is preferably in the range of 2000 to 130°C, more preferably in the range of 40 to 100 qo. Furthermore, it is preferable to adopt a reaction pressure that is necessary to maintain isobutylene in a liquid state within the catalyst bed, but it is of course not necessary to be limited to this, and the reaction can also be carried out at a pressure where a part of isobutylene is in a gaseous state. can. The reaction pressure usually employed is about 1 to 50 k9/m. In the method of the present invention, the reaction can also be carried out by adding water to the system,
．． In this case, the etherification reaction and the hydration reaction occur in parallel, and tertiary butyl alcohol is produced together with ethylene glycol monotertiary butyl ether. The method of the present invention suppresses by-products such as ethylene glycol ditertiary butyl ether and diisobutylene even under conditions where the conversion rate of raw materials is high, such as low liquid hourly space velocity or high reaction temperature. Ethylene glycol monotertiary butyl ether can be obtained with good selectivity.

It was completely unexpected that increasing the linear velocity decreased the production of the product ethylene glycol ditertiary butyl ether and increased the production of the target product ethylene glycol monotertiary butyl ether. EXAMPLES Next, the present invention will be specifically explained using Examples and Comparative Examples, but the present invention is of course not limited to these.

Further, the isobutylene conversion rate and product selectivity described in these are defined by the following equations. Isobutylene conversion rate (mol %) = (number of moles of isobutylene in the raw material) - (number of moles of unreacted isobutylene) xl.

〇Number of moles of isobutylene in the cutting charge) Each product ratio (monole%) = Kagossan Fort Sugata Tori Fort Kurate Tsuba Sagi Sueo Suzuo Suzumon Multi side Example 1
In a stainless steel reaction tube with an inner diameter of 1.34 cm, a commercially available macroporous type strongly acidic ion exchanger ≠ sword resin Amberlyst 15, which had been swollen with ethylene glycol, was added to 211.
'Filled'.

The reaction temperature was maintained at 4500℃ and the pressure was maintained at 20kg/c.
Total liquid volume F of naphtha decomposition C4 crab fraction (containing 45M% isobutylene) and ethylene glycol at room temperature
It was fed from the top of the reaction tube at a rate of =211'/hr. The relative amounts of the C4 fraction and ethylene glycol were determined so that the molar ratio of ethylene glycol to isobutylene was 2.7. In this case, the space velocity of the raw material liquid LHS
As mentioned earlier, V is F/V=211/211=1.0
hrl, and the raw material linear velocity is F/S=211/(3.1
4) (Science) 2 = cost r multiplied. When the reaction product was analyzed by gas chromatography, the conversion rate of isobutylene was 88.1 mol%, and the selectivity of the product was 3.0 mol% for diisobutylene, 90.9% for ethylene glycol monotertiary butyl ether, 6.1 mol% of ethylene glycol ditertiary butyl ether;
Additionally, significant amounts of triisobutylene and ethylene glycol monosecondary butyl ether were produced.

Example 2 Similarly to Example 1, a stainless steel reaction tube with an inner diameter of 1.34 mm was filled with 440 mm of Amberlyst 15.

The reaction conditions and raw materials were the same as in Example 1, the reaction raw material supply rate was 440 units/hr, and the raw material liquid hourly space velocity (LHSV) was 1. Blood r-1, and the raw material linear velocity is 312 k/hr. When the reaction product was analyzed by gas chromatography, the conversion rate of isoptylene was 97.2 mol%, and the selectivity of the product was 0.9 mol% for diisobutylene, 0.4 mol% for triisoptylene, and ethylene glycol monotersia. Libutyl ether is 91.6 mol%, ethylene glycol ditertiary butyl ether is 7.1 mol%
% by mole, and a significant amount of ethylene glycol monosecondary butyl ether was also produced. Comparative Example 1 As in Examples 1 and 2, Amberlyst 15 and 113 were filled in a stainless steel reaction tube with an inner diameter of 1.34 mm.

The reaction conditions and raw materials were the same as in Example 1, the reaction raw material supply rate was 113 K/hr, and the raw material liquid hourly space velocity (LHSV) was 1.
The plate is r-1 and the raw material linear velocity is 80 k/hr. When the reaction product was analyzed by gas chromatography,
The conversion rate of isobutylene is 84.2 mol%, the selectivity of the product is 1.9 mol% for diisobutylene, 0.1 mol% for triisobutylene, 66.0 mol% for ethylene glycol monotert-butyl ether, Ethylene glycol ditertiary butyl ether was 32.0 mol %, and a small amount of ethylene glycol monosecondary butyl ether was also produced.

According to the results of Examples 1 and 2 and Comparative Example 1, under the conditions of a reaction temperature of 45 oo and a liquid hourly space velocity of 1.0 hr-1, when the linear velocity exceeds 120 c/hr, the target ethylene glycol monotertiary butyl ether This shows that the selectivity of ethylene glycol monotertiary butyl ether increases rapidly and the amount of ethylene glycol monotertiary butyl ether by-product increases rapidly when the linear velocity is less than 120 k/hr.

Although reactors with the same inner diameter were used in Examples 1 and 2 and Comparative Example 1, the same tendency as described above was observed when reactors with different inner diameters were used. Example 3 A stainless steel reaction tube with an inner diameter of 1.34 cm was filled with 120 μl of Amberlyst 15.

The reaction temperature was maintained at 60°C and the pressure was maintained at 20 kg/kg, and the naphtha-decomposed C4 fraction (containing 45 wt% isobutylene) and ethylene glycol were added in a total liquid volume of 24 at room temperature.
It was fed from the top of the reaction tube at a rate of 0 '/hr.
Note that the molar ratio of ethylene glycol to isobutylene is 2.7. In this case, the raw material liquid hourly space velocity (LHSV
) is 20hr-1 and the raw material linear velocity is 170c/hr
It is. When the reaction product was analyzed by gas chromatography, the conversion rate of isobutylene was 89.0 mol%.
The selectivity of the product was 0.5 mol% for diisobutylene and 88% for ethylene glycol monotert-butyl ether.
．． 1 mol %, ethylene glycol ditertiary butyl ether was 11.4 mol %, and other amounts of triisobutylene and ethylene glycol mono-sec-butyl ether were produced. Comparative Example 2 A stainless steel reaction tube with an inner diameter of 1.34 mm was filled with 70.5 mm of Amberlyst 15.

Under the same reaction conditions as in Example 3, the same reaction raw materials were mixed at 141[/h]
It was fed from the top of the reaction tube at a rate of r. In this case, the raw material liquid space velocity LHSV is 2 plates r-1, and the raw material linear velocity is 100 k/hr. When the reaction product was analyzed by gas chromatography, the conversion rate of isobutylene was 89.0 mol%, and the selectivity of the product was 89.0 mol%.
5.3 mol%, triisobutylene 0.4 mol%, ethylene glycol monotertiary butyl ether 33
．． 7 mol%, ethylene glycol ditertiary butyl ether was 50.6 mol%, and a small amount of ethylene glycol monosecondary butyl ether was also produced.

Compared to Example 3, the selectivity of the target object is lower. Example 4 A stainless steel reaction tube having an inner diameter of 1.34 mm was filled with 80 g of Amberlite 118, a gel-type strongly acidic ion exchange resin that had been swollen with ethylene glycol.

The reaction temperature was maintained at 75 qo and the pressure was maintained at 20 k9, and the naphtha cracked C4 fraction (containing 45 wt% isobutyrene) was
and ethylene glycol were fed from the top of the reaction tube at a rate of 240/hr of total liquid volume at room temperature. The relative amounts of the C4 fraction and ethylene glycol were determined so that the molar ratio of ethylene glycol to isobutylene was 2.7. Therefore, the raw material liquid hourly space velocity LHSV
is 3. ohr-1, and the raw material linear velocity was 170 skin/hr. When the reaction product was analyzed by gas chromatography, the conversion rate of isobutylene was 84.0 mol%, and the selectivity of the product was 1.5 mol% of diisobutylene.
, 0.1 mol% triisobutylene, ethylene glycol
79.8 mol% of tertiary butyl ether,
Ethylene glycol ditercia IJ-butyl ether was 18.6 mol %, and a small amount of ethylene glycol monosecondary butyl ether was also produced.

Comparative Example 3 A stainless steel reaction tube with an inner diameter of 1.34 mm was filled with 45 mm of Amberlite 118.

The same reaction raw material was used at 135 m'/h under the same reaction conditions as in Example 4.
It was fed from the top of the reaction tube at a rate of r. In this case, the raw material liquid space velocity LHSV was 3.0 hr-1, and the raw material linear velocity was 96 skin/hr. When the reaction product was analyzed by gas chromatography, the conversion rate of isoptylene was 83.5 mol%, and the selectivity of the product was 5.5 mol% for diisobutylene, 0.5 mol% for triisobutylene, and ethylene glycol monomer. Tertiary butyl ether was 40-4 mol%, ethylene glycol di-tert-butyl ether was 53-6 mol%, and a small amount of ethylene glycol monosecondary butyl ether was also produced.

Example 5 A stainless steel reaction tube with an inner diameter of 1.34° was filled with 100 μm of Amberlyst 15.

The reaction temperature was maintained at 45 oo and the pressure was maintained at 20 k9/kg, and the naphtha cracked C4 fraction (containing 45% isobutylene) and ethylene glycol were added in a total liquid volume of 10 at room temperature.
It was fed from the top of the reaction tube at a roaring rate of 0/h. The relative amounts of the C4 fraction and ethylene glycol were determined so that the molar ratio of ethylene glycol to isobutylene was 2.7. In this example, a circulation reaction method was adopted in which a portion of the reaction product at the reactor outlet was returned to the reactor inlet.

The feed rate of new reaction raw materials was 100/hr, and the circulation rate was 2/3 of the total amount of reaction products at the outlet of the reactor, 300/hr. That is, in this example, since the raw material liquid hourly space velocity LHSV is the amount of catalyst and the amount of raw material processed per unit time, it is 10 as before.
It is defined as 0/100=1.0hr-1, but the total rate of passage of feedstock including recycle through the catalyst bed is 300/(3.14)(
Sheep) 2F212ka/hr.

When the reaction product was analyzed by gas chromatography, the conversion rate of isobutylene was 79.0 mol%, and the selectivity of the product was 0.2 mol% of diisobutylene, 90.2 mol% of ethylene glycol monotertiary butyl ether, and ethylene. 9.6 mol % of glycol ditertiary butyl ether was produced, as well as significant amounts of triisobutylene and ethylene glycol monosecondary butyl ether.

Comparative Example 4 As in Example 5, 100 volumes of Amberlyst 15 were filled into a stainless steel reaction tube with an inner diameter of 1.34mm.

The reaction conditions and raw materials were the same as in Example 5, with a new feedstock flow rate of 100 M/hr. In this comparative example as well, a circulation reaction method was adopted in which a portion of the reaction product at the reactor outlet was returned to the reactor inlet.

The circulation rate is the total amount of reaction products at the reactor outlet: 125 kg/hr
The rate was set at 1'5, or 25 units/hr. The linear velocity of the feedstock containing recycled materials passing through the catalyst bed is 125/(3.14)2=br/hr. When the reaction product was analyzed by gas chromatography, the conversion rate of isobutylene was 8.
The selectivity of the product is 1.6 mol% for diisobutylene, 0.1 mol% for triisobutylene, and 6 mol% for ethylene glycol monotertiary butyl ether.
2.5 mol%, ethylene glycol di-tert-butyl ether was 35.8 mol%, and a small amount of ethylene glycol mono-secondary butyl ether was also produced.

In Example 5 and Comparative Example 4, the reaction product was recycled and the influence of linear velocity was examined.
It is shown that the selectivity of the target ethylene glycol monotertiary butyl ether increases when the number of cycles exceeds hr.

Example 6 A stainless steel reaction tube with an inner diameter of 1.34 cm was filled with 120 Amberlyst 15 birds.

The reaction temperature was maintained at 60° C. and the pressure was maintained at 20×9/m2, and the naphtha decomposition C4 fraction (containing 45% by weight of isobutylene),
Ethylene glycol and water were fed from the top of the reaction tube. The molar ratio of ethylene glycol:water:isobutylene was 2.7:0.5:1.0. In this case, the raw material liquid hourly space velocity (LHSV) is 2. The rib was r-1, and the raw material linear velocity (empty tube) was 170 skins/hr. Analysis of the reaction product by gas chromatography revealed that the conversion rate of isoptylene was 78.5 mol%, the selectivity of the product was 0.2 mol% for diisobutylene, and ethylene glycol monotertiary 1'-butyl ether. 7.5 mol%, ethylene glycol ditertiary butyl ether 10.2 mol%, and tertiary butyl alcohol 12.1 mol%.

Claims (1)

[Claims] 1 In a method for producing ethylene glycol monotertiary butyl ether by reacting ethylene glycol and isobutylene in the presence of a strongly acidic cation exchange resin as a catalyst, a fixed bed flow reactor is used, and a catalyst bed of raw materials is used. 1. A method for producing ethylene glycol monotertiary butyl ether, characterized in that the reaction is carried out at a passing linear velocity (value calculated as a liquid state) of 120 cm per hour or more.