JPS60224652A - Production of 3-methyl-2-buten-1-al - Google Patents

Abstract

PURPOSE:To obtain the titled compound in high conversion and selectivity, with increased effective surface area of the catalyst, and in high reaction activity with small amount of the catalyst, by carrying out the catalytic reaction of prenol with molecular O2 in vapor phase at a specific temperature using a specific oxidative dehydrogenation catalyst. CONSTITUTION:The objective compound can be produced by the vapor-phase catalytic reaction of prenol (=3-methyl-2-buten-1-ol) with molecular O2 at 300- 600 deg.C, in the presence of a catalyst prepared by supporting silver and copper on a carrier having a specific surface area of <3m<2>/g, e.g. quartz, fused alumina, etc., and if necessary, in the presence of the nitrogen compound of formula (R<1>- R<3> are H or lower alkyl) as a side-reaction suppressing agent. The weight ratio of silver to copper supported on the carrier is 99:1-50:50. EFFECT:Effective to dissipate and removed the heat of reaction, to suppress the sintering of the metallic components of the catalyst caused by the local super- heating during the reaction and activation, and to stabilize the microscopic structure of the active part of the catalyst. The amount of the reaction gas can be varied over a wide range in this process.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for producing 3-methyl-2-buten-1-al.

[Technical background of the invention and its problems]

Conventionally, 3-methyl-2-buten-1-ol (hereinafter referred to as prenol) is dehydrogenated by contacting it with an oxidative dehydrogenation catalyst in the gas phase to produce 3-methyl-2-buten-1-al (hereinafter referred to as prenol). Methods for producing senecioaldehyde (called senecioaldehyde) are known. For example, JP-A-53-137906
The specification describes that in the production of 3-alkyl-buten-1-al such as senecioaldehyde by oxidative dehydrogenation of altenol such as prenol by passing it over a catalyst with oxygen, each of The above-mentioned 3-alkyl-glucose catalyst is characterized in that it uses a multilayer catalyst with silver and/or steel particles consisting of two or more layers of particles with a particle size of a certain size. A method for producing /-1-R is described.

However, the catalyst used in this method contains silver and/or steel in the form of particles and has a special layer structure, so its preparation is not easy industrially.

U.S. Pat. No. 2,042,220 also describes a method for producing the corresponding unsaturated aliphatic aldehydes by oxidizing unsaturated aliphatic alcohols with oxygen in the presence of an oxidation catalyst and at elevated temperatures. Are listed. In this method, it is said that it is appropriate to use an activated oxidation catalyst, such as reducing copper oxide wire at 300°C in a hydrogen atmosphere! Silver catalysts manufactured by Ov4 are used, such as those made by removing mercury by amalgamating the 1-mesh and heating it at 600°C, but these catalysts are not industrially suitable. Difficult to hire. Also, the second German patent
No. 041976gAIiBI describes that prenol is prepared in the gas phase at a temperature of 150 to 600°C in the presence of a dehydrogenation catalyst such as steel, silver, or zinc, and furthermore, a nuclear aliphatic organic nitrogen compound, an aromatic organic nitrogen compound, In the presence of a phosphorus compound or a sulfur compound or in the presence of ammonia gas and/or the presence of a basic metal oxide such as barium oxide, calcium oxide, magnesium oxide as a carrier for the dehydrogenation catalyst or as an additive to the dehydrogenation catalyst. A method for producing senecioaldehyde by dehydrogenation is disclosed below. It has been pointed out that in this method, when oxygen is present, the oxidation of prenol progresses too much and the amount of "C dimethylacrylic acid" produced increases, resulting in a significant decrease in the yield of senecioaldehyde.

[Purpose of the invention]

An object of the present invention is to solve the problems of the conventional methods as described above and to provide an improved production method for producing senecioaldehyde by contacting prenol with an oxidative dehydrogenation catalyst in the gas phase together with oxygen. .

[Structure of the invention]

The present invention is characterized in that prenol is brought into contact with molecular oxygen in a gas phase at a temperature of 300 to 600°C with a catalyst comprising two components, silver and steel, supported on a carrier having a specific surface area of less than 3. This invention relates to a method for producing aldehydes.

[Detailed description of the invention]

The catalyst to be consumed in the method of the present invention has two components, silver and copper, supported on a carrier with a specific surface area of less than 312 as measured by the LINT method. Must be less than 3Cv to obtain special V
It is preferable that nl/I is full. If the specific surface area of the carrier is large, a reaction will occur and a large amount of isobutyne, imprene, etc. will be produced as by-products. As a support, quartz sand with a small specific surface area as described above, fused alumina, fused silica, silicon carbide, hydroxyapatite [Ca
2O(PO4)6(OH)2], pumice, etc. are used.

In addition to the fact that the selectivity to hepta-unthioaldehyde can be increased by using such a carrier, the effective surface area of the catalyst is increased compared to when no carrier is used, and a large activity can be obtained with a small amount of catalyst. be advantageous in dispersing and removing reaction heat, suppress sintering of the catalyst metal component due to local overheating during reaction and activation, stabilize the fine structure of the active part, and accommodate a wide range of reaction gas amounts. This brings about industrial advantages such as ease of responding to changes. In addition, it is preferable to use a carrier with a small amount of acid in order to improve the selectivity to -senecioaldehyde, for example, 2 x 10 m as measured by amine titration.
Those having an acid content of mot/f or less are suitable.

When a catalyst in which only either silver or copper is supported on the above-mentioned carrier is used, both the conversion rate of prenol and the selectivity to nesioaldehyde decrease. The ratio of silver and steel supported on the carrier is 99:1 to 50:5 by weight.
A range of 0 is preferred, and a range of 98:2 to 90:10 is particularly preferred.

The total weight of silver and copper supported on the carrier is 0 relative to the carrier.
．． It is 1 to 30% by weight, preferably 1 to 15% by weight.

A smaller amount of silver and copper supported is preferable in terms of reducing catalyst cost, but if the amount supported is less than 0.1 weight it, the selectivity to prenol conversion vehicle and senecioaldehyde will decrease. So I don't like it. Furthermore, if the supported amount exceeds 30 weight SL-, a catalytic effect commensurate with the excess amount cannot be obtained, and the cost of the catalyst increases, so it is not preferable to use it in confectionery production.

The oxidative dehydrogenation catalyst used in the method of the present invention is prepared by impregnating the above-mentioned carrier with a predetermined amount of aqueous solution of silver nitrate and steel nitrate, and then calcining it in air at a temperature of about 300 to 400°C, and then baking it in air at a temperature of about 300 to 400°C. It can be easily prepared by treatment with hydrogen at a temperature of 300-500°C. The catalyst bed used in carrying out the present invention is suitably a fluidized bed or a multi-tubular fixed bed.

The oxidative dehydrogenation reaction in the present invention is carried out in the gas phase at 300 to 600
C, preferably within a temperature range of 400 to 500C. It is necessary to set the maximum temperature of the catalyst layer to be within this temperature range.

At temperatures lower than 300°C, the yield of senecioaldehyde per unit volume of the catalyst becomes small, and at temperatures above 600°C, the 11 reaction occurs significantly, shortening the active life of the catalyst. This oxidative dehydrogenation reaction is an exothermic reaction, and in order to maintain the temperature of the catalyst layer within the above temperature range, it is necessary to remove heat by an appropriate method. Heat removal methods include, for example, cooling the reaction zone (catalyst layer) from the outside with a suitable heating medium, and adding about 0.5 to 2 times the volume of the feed gas at the same time as the raw prenol feed gas. Either a method of supplying an inert gas to the reaction zone or a combination of these methods can be employed. The inert gases used include nitrogen, helium, and
Water vapor is suitable.

However, the catalyst used in the method of the present invention can also be diluted with inert particles such as glass beads, quartz sand, fused alumina, etc. to increase the heat transfer area and facilitate heat removal. .

The molecular oxygen used in the oxidative dehydrogenation reaction in the second aspect of the present invention may be diluted with nitrogen, argon, helium, water vapor, or the like. Specifically, it is convenient to use air. It is preferable to use less than the stoichiometric amount of molecular oxygen relative to prenol, and specifically, it is appropriate to use 0.2 to 0.4 mol per 1 mol of prenol, approximately 0.4 mol or less. Deroru. As the ratio of molecular r11 to prenol increases, the conversion rate of glenol increases, but the selectivity to senecioaldehyde decreases and it becomes difficult to remove the heat of reaction.

The amount of prenol supplied to the reaction zone is LH8v (liquid volume of prenol supplied per hour per unit volume of catalyst)
A suitable range is approximately 0.5 to 60 hr. Within this range, if the usage ratio with molecular oxygen is the same, LH8
The selectivity to senecioaldehyde tends to increase as V increases, but it is usually preferable to select LH8V'i from within the range of 3 to 20 hr from the viewpoint of heat removal. However, when trying to obtain a higher space-time yield (STY), a higher value of LHE3V can be adopted. The residence time of the reaction gas on the catalyst is preferably 1 second or less.

In the method of the present invention, in order to suppress side reactions, a nitrogen compound represented by the general formula RIR"R3N (wherein R1, R2 and R3 each represent a hydrogen atom or a lower alkyl group) is added as necessary. It is preferable to carry out an oxidative dehydrogenation reaction.In the above formula, R', f, and R3 are each specifically a hydrogen atom; a lower alkyl group such as a methyl group, an ethyl group, or a propyl group.As a nitrogen compound, Ammonia, methylamine, ethylamine, dimethylamine, trimethylamine, triethylamine, etc. can be used, but ammonia is most preferred from the viewpoint of ease of handling, availability, and low price. Specifically, ammonia water is vaporized. It is convenient to use the nitrogen compound in an amount of about 0.05 to 3% by weight, preferably about 0.1 to 3% by weight based on the prenol.
It is used in a proportion of 1% by weight and is fed onto the catalyst together with prenol.

Separation and recovery of senecioaldehyde from reaction product residue 1
For example, this can be easily carried out by cooling the reaction product gas and distilling the condensate.

The senecioaldehyde produced by the method of the present invention is useful as a synthetic intermediate for, for example, citral, β-ionone, chrysanthemum acid, and the like.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 /l, AoI (engineering, Maruta Bato. + H20 fused alumina (manufactured by Twotone, 5A-5221, 1/8" spherical,
Specific surface area measured by BET method: 0.05: M/2) of 70
m Gold silver nitrate 37.3% by weight, cupric nitrate trihydrate 10
．． Mixed aqueous solution 1 consisting of 0% by weight and 52.7% water
After immersing in 0TRIK and removing excess mixed aqueous solution by decantation, it was dried at 150° C. for 3 hours under reduced pressure. This was heated at 300 to 350℃ at 300 d/mi.
Baked for 4 hours under air circulation of 350-45
Reduction was carried out at 0°C for 5 hours under a hydrogen flow of 500 n/ml. The weight ratio of silver to copper in the catalyst thus prepared was 9.1, and the total weight of silver and steel supported on fused alumina was 10% by weight.

The prepared catalyst 101III was packed into a glass tube with an inner diameter of 20°C and heated to 300°C, and prenol to which 25 ml of ammonia water was added in an amount of 25% by weight was added to the catalyst layer using LH.
8V13. Qhr and at the same time air 560xj
It was supplied at a rate of /min. Four hours after the start of supply, the maximum temperature of the catalyst layer reached 460° C. when the reaction reached a steady state.

The reaction solution obtained during the 1 hour period from 4 hours after the start of the reaction until 5 hours of salmon feeding was quantified using an internal standard method.
The conversion rate of prenol was 56.1%, and the selectivity to senecioaldehyde was 88.4 mol. In addition to senecioaldehyde, trace amounts of isobutyne, isoprene, isovaleral, and 3-methyl-3-buten-1-al were produced as by-products.

Examples 2 to 5 and Comparative Examples 1 to 2 The total supported weight of silver and/or copper on fused alumina was kept constant at 10% by weight, and the weight ratio of silver and copper was varied and a phosphorus catalyst was used. 9. The reaction was carried out in the same manner as in Example 1. The reaction solution was quantitatively determined in the same manner as in Example 1, and the reaction results are shown in Table 1 together with those in Example 1.

Table 1 Note that in Comparative Examples 1 and 2, a large amount of isobutyne and isoprene were produced as by-products (selectivity 5 to 15 mol), but in Examples 2 to
5, trace amounts of isobutyne and isoprene (selectivity 1-2
(mol%) was only a by-product.

Example 6 A reaction was carried out in the same manner as in Example 1 except that the amount of 25% ammonia water added to prenol was changed.

The reaction solution was quantitatively determined in the same manner as in Example 1, and the reaction results are shown in Table 2 together with those in Example 1.

Table 2 Examples 7 to 8 The reaction was carried out in the same manner as in Example 1 except that 25% aqueous methylamine or triethylamine was used instead of 25% aqueous ammonia. The reaction solution was quantitatively determined in the same manner as in Example 1, and the reaction results are shown in Table 3 together with those in Example 1.

Table 3 Examples 9 to 13 and Comparative Example 3 A catalyst 70d prepared in the same manner as in Example 1 was used with an inner diameter of 20 m.
Prenol t-LH8V was charged into a glass reaction tube, and 1.0% by weight of 25 thiammonia water was added thereto.4.
The reaction was carried out in the same manner as in Example 1 except that the molecular oxygen was supplied at a rate of 1 hr and the amount of molecular oxygen supplied was varied. Example 1
The reaction solution was quantified in the same manner as above, and the reaction results are shown in Table 4.

Table 4 Note 1) Examples 14 to 19 and Comparative Examples 4 to 5 where the selectivity to isoprene was 65.5 mol. Catalysts prepared in the same manner as in Example 1 using various carriers [silver and copper Weight ratio: 9:11 Total supported weight of silver and copper on support = 10% by weight (excluding the case of Example 14 and Example 18) 1 0% by weight of prenol was supplied at LM SV 10.0 hr, molecular oxygen was supplied at a ratio of 0.35 molar amount to cough prenol, and the reaction was carried out at 450°C.

The reaction solution was quantified in the same manner as in Example 1, and the reaction results are shown in Table 5.

Examples 20 to 29 Catalysts prepared in the same manner as in Example 1 (weight ratio of silver and copper:
9:1, total loading weight of silver and steel to fused alumina:
2% by weight)) 301Llt- was used, and prenol with 1.0% by weight of 25 thiammonium water added on the catalyst was supplied at various LH8V (hr), and the ratio was 0.2 times the mole amount to the prenol. supplying molecular oxygen at 450
Reactions were carried out at ~480°C.

The reaction solution was quantitatively determined in the same manner as in Example 1, and 1 ml of the reaction solution is shown in Table 6.

Examples 30 to 33 Using a catalyst prepared in the same manner as in Example 1 or diluting it with 4 φ glass beads, 2
Example 1 was carried out in the same manner as in Example 1, except that 1.0 wt. 9. Carry out the reaction. The reaction solution was quantified in the same manner as in Example 1, and the reaction results are shown in Table 7.

Table 7 Examples 34 to 37 Catalyst 70d't-inner diameter 2 prepared in the same manner as in Example 1
1L of prenol added to a 0-glass reaction tube and 1.0% by weight of 25thia/monia water) isV5
．． The reaction was carried out in the same manner as in Example 1, except that molecular oxygen was supplied at a ratio of 0.3 molar amount to the prenol, and nitrogen was further supplied at various ratios. The reaction solution was quantitatively determined in the same manner as in Example 1, and the reaction bottom M'fc is shown in Table 8.

Table 8 Examples 38 to 39 Prenol to which no ammonia water was added in Example 14 was added to LH8V10. The reaction was carried out in the same manner except that molecular oxygen was supplied at a ratio of 0.35 molar amount to the prenol and the reaction temperature was changed, and the reaction solution was quantified in the same manner. . The results are shown in Table 9.

Table 9 Example 40 Prenol LH8V12.25 in Example 1 to which 1.0% by weight of ammonia water was added. supplied in Ohr;
The reaction was carried out in the same manner for 240 hours except that molecular oxygen was supplied at a ratio of 0.3 molar amount to the prenol. As shown in Table 10, there was no noticeable decrease in reaction results.

Table 10 Part of the reaction solution obtained in this continuous reaction 25802 contains triethanolamine 1f and hydroquinone 0.5Fk:
After adding water and removing water under reduced pressure of 100 mHf, the mixture was distilled under reduced pressure to reduce the boiling point to 63.
℃/57 wm 857.5r of senecioaldehyde was obtained as a fraction of HP. The purity of this product was 99.0%, and the distillation recovery rate was 97.5%.

〔Effect of the invention〕

By the method of the present invention, f″L can obtain senecioaldehyde from prenol with high selectivity. It's a method.

Patent applicant RiRashi Co., Ltd. Representative Patent Attorney Kan Honda

Claims (1)

[Claims] l 3-Methyl-2-buten-1-ol in the gas phase
3-Methyl-2-butene is brought into contact with molecular oxygen at a temperature of 0 to 600°C with a catalyst comprising two components, silver and copper, supported on a carrier having a specific surface area of less than 3 t11/. -1-A manufacturing method of R. 2. The manufacturing method according to claim 1, wherein the ratio of silver and steel supported on the carrier is 99:1 to 50:50'''C by weight. 3. General formula R'R2R3N (wherein, Hl , R2 and R3 each represent a hydrogen atom or a lower alkyl group. 5. The manufacturing method according to claims 1 to 3, wherein the carrier is fused flumina.
Manufacturing method described in section. 6. The manufacturing method according to claims 1 to 3, wherein the carrier is fused silica.