JPH02275850A - Production of epsilon-caprolactam - Google Patents

Abstract

PURPOSE:To obtain the subject compound in high selectivity even in the case of high reaction ratio and in an improved life of catalyst by adding a lower alcohol to a reaction system and rearranging cyclohexanone oxime under a gaseous phase reaction condition by using a solid acid catalyst. CONSTITUTION:Cyclohexanone oxime is subjected to gaseous phase Beckmann rearrangement reaction in the presence of a lower alcohol, preferably methanol or ethanol by using a silicon oxide-containing catalyst, especially crystalline metallosilicate or crystalline silicate of pentasil type at 250 to 500 deg.C, preferably 300 to 400 deg.C reaction temperature at 0.1 to 40hr<-1>, preferably 0.5 to 10hr<-1> space velocity of raw material to give epsilon-caprolactam. The amount of the lower alcohol present in the reaction system is preferably 0.3 to 8 pts.wt. based on 1 pt.wt. cyclohexanone oxime.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing ε-caprolactam from cyclohexanone oxime under gas phase reaction conditions using a solid acid catalyst.

<Prior art and problems to be solved by the invention> ε-caprolactam is an important basic chemical raw material used as a raw material for nylon, etc., and its manufacturing method has conventionally used fuming sulfuric acid or concentrated sulfuric acid as a catalyst. A method has been adopted in which cyclohexanone oxime is rearranged under the liquid phase.

However, this method not only requires a large amount of fuming sulfuric acid, but also has the problem of producing a large amount of ammonium sulfate as a by-product.

On the other hand, various methods have been proposed to solve this problem by using solid acid catalysts and rearranging them in the gas phase. Publication No. 831.927), silica-alumina catalyst (British Patent No. 831.927), solid phosphoric acid catalyst (
British Patent No. 881.926), composite metal oxide catalyst (
Journal of the Chemical Society of Japan, 1977, (1) 77), Zeolite Catalysts (Journal of Catalysis)
fL, 247 (1966), JP-A-57-13906
There is a method using Publication No. 2) etc. However, in both methods, the reaction selectivity of the target ε-caprolactam, the catalyst life, the productivity per catalyst, or the product ε-caprolactam, etc.
There are issues with the quality of caprolactam.

For example, JP-A-57-139062 discloses ZSM having an Si/A1 atomic ratio of 40 to 60 as a catalyst.
A specific example using a crystalline zeolite such as -5 is shown, and although the reaction rate of cyclohexanone oxime is described as quantitative, there is no mention of the selectivity of ε-caprolactam, and the catalyst life is 15 to 20%. Time and short results are shown.

The present inventors also used Si/Al as described in the publication.
Although ZSM-5 zeolite with an atomic ratio was actually investigated as a catalyst, not only the life of the catalyst but also the selectivity to ε-caprolactam were found to be insufficient.

On the other hand, JP-A-62-123167, JP-A-63-
Publication No. 54358 describes the use of crystalline aluminosilicate with an Si/Al atomic ratio of 500 or more and the amount of acid outside the pores below a specific value, or crystalline metallosilicate with an St/metal atomic ratio of 500 or more as a catalyst. An example is shown. The selectivity of this product is considerably improved compared to the conventional silica-based catalyst technology, and is further improved in JP-A No. 62-2818.
No. 56 discloses that the selectivity can be improved by treating the surface of crystalline zeolite with an organometallic compound.

Means for Solving the Problems> In view of the current situation, the present inventors investigated a gas phase Beckmann rearrangement reaction using a solid acid catalyst that is superior to the conventional method. The reaction rate of cyclohexanone oxime can be increased to, for example, substantially 100% by coexisting a lower alcohol with
%, it was found that ε-caprolactam could be obtained with extremely high selectivity, and the life of the catalyst was also significantly improved, leading to the completion of the present invention.

That is, the present invention provides a method for producing C-caprolactam from cyclohexanone oxime using a solid acid catalyst, which is characterized by allowing a lower alcohol to coexist in the reaction system.

The present invention will be explained in detail below.

In the present invention, a solid acid is used as a catalyst. Among solid acids, silicon oxide-containing catalysts, especially crystalline metallosilicates, are preferred, especially the St/Me atomic ratio (where Me is AI, Ga, Fe).

B, Zn, Cr, Be, Co, La, Ge, Ti.

Zr, Hf, V, Ni, Sb, B
A crystalline metallosilicate in which one or more metal elements selected from L, Cu, Nb, etc.) is 5 or more is more preferable, and a crystalline silicate consisting of silicon dioxide that does not substantially contain Me acid component is preferred. is also more preferable.

The Si/Me atomic ratio can be determined by conventional analytical means such as atomic absorption spectrometry and fluorescent X-ray analysis.

Moreover, these catalysts are manufactured by known methods. Although various crystal forms of these crystalline metallosilicates and crystalline silicates are known, those belonging to the so-called pentasil type structure are particularly preferred.

In the present invention, a lower alcohol is allowed to coexist with cyclohexanone oxime in the reaction system, and the alcohol used here is preferably a lower alcohol having 6 or less carbon atoms. For example, methanol, ethanol, n-propanol, isopropanol, n-butanol, 5e
One or more of c-butanol, isobutanol, n-amyl alcohol, n-hexanol, 2,2,2-trifluoroethanol, etc. can be used. In particular, it is more preferable to use one or more of methanol, ethanol, n-propanol, isopropanol, and n-butanol, as this is highly effective in improving the selectivity of ε-caprolactam and catalyst life. Among them, methanol or ethanol exhibits remarkable effects and is the most preferred from an industrial standpoint.

Further, in the present invention, a molecular oxygen-containing gas can be allowed to coexist with a lower alcohol in the reaction system.

It is economical and preferable to use air as the molecular oxygen-containing gas.The concentration of zero molecular oxygen is preferably outside the explosive composition range.

Furthermore, the present invention is typically carried out at atmospheric pressure or at reduced pressure below atmospheric pressure.

Next, a reaction method for carrying out the present invention will be described.

The reaction is carried out by a gas phase contact reaction using a normal fixed bed method or fluidized bed method.The raw material cyclohexanone oxime is reacted in a gaseous state with the catalyst layer, but the lower alcohol is premixed with the cyclohexanone oxime in a gaseous state. Alternatively, it may be supplied to the reactor separately from cyclohexanone oxime. In the case of a fixed bed reaction, it is preferable that the cyclohexanone oxime and the lower alcohol pass through the catalyst bed in a sufficiently mixed state, or in the case of a fluidized bed reaction. The cyclohexanone oxime and the lower alcohol do not necessarily need to be mixed in advance; they can be supplied separately, and the lower alcohol can also be added in portions. Furthermore, in the case of a fluidized bed reaction, the lower alcohol may be added upstream of the cyclohexanone oxime.

Furthermore, the molecular oxygen-containing gas can be supplied in a mixture with a lower alcohol, cyclohexanone oxime, or mixed with a lower alcohol, or the molecular oxygen-containing gas can be added upstream of the cyclohexanone oxime.

The amount of lower alcohol allowed to coexist in the reaction system is usually 0.1 to 20 times, preferably 10 times or less, and most preferably 0.1 to 20 times the weight of cyclohexanone oxime. A range of 3 to 8 times is preferable.

When a molecular oxygen-containing gas is allowed to coexist with the lower alcohol, the appropriate amount of molecular oxygen is usually 0.1 to 10 times the molar ratio of cyclohexanone oxime. More preferably, it is 0.3 to 5 times.

In the present invention, a vapor of a compound inert to the reaction such as benzene, cyclohexane, toluene, etc., or an inert gas such as nitrogen, carbon dioxide, etc. may be allowed to coexist in the reaction system as a diluent gas.

The reaction temperature of the present invention is generally preferably in the range of 250°C to 500°C; at temperatures below 250°C, the reaction rate is insufficient and the selectivity of ε-caprolactam tends to decrease. On the other hand, if the temperature exceeds 500°C, the thermal decomposition of cyclohexanone oxime cannot be ignored, so the selectivity of ε-caprolactam tends to decrease. A particularly preferred temperature range is 300°C to 450°C, and the most preferred temperature range is 300°C to 400°C.

The space velocity of the raw material cyclohexanone oxime is WH3V
=0.1 to 40 hr-' (i.e. cyclohexanone oxime feed rate per kg of catalyst 0.1 to 40 k
g/hr), preferably 0.2 to 20 hr-', more preferably 0. Selected from the range of 5 to 10 hr-'.

Separation of ε-caprolactam from the reaction mixture can be carried out by a conventional method. For example, the reaction product gas is cooled and condensed, and then purified ε-caprolactam can be obtained by extraction, distillation, crystallization, etc.

The lower alcohol added to the rearrangement reaction system can be separated and recovered from the reaction product and reused.

Further, a catalyst whose activity has decreased due to long-term use can be easily reactivated to its original performance by firing in a stream of air, and can be used repeatedly.

<Effects of the Invention> As detailed above, according to the present invention, even under conditions where the reaction rate of cyclohexanone oxime is substantially around 100%, ε-caprolactam is extremely effective.

produced with high selectivity. Also, in the process of the present invention, the lifetime of the catalyst is significantly improved compared to conventional processes. Furthermore, since the alcohol added to the reaction system can be recovered, it can be used again.

<Examples> The present invention will be specifically described below with reference to Examples, but the present invention is not limited thereto.

Reference Example 1 (Preparation of Catalyst A) 1.5j! Tetraethyl orthosilicate (S i (QC!H5) 4, A
224.0 g of a 10% aqueous tetra-n-propylammonium hydroxide solution and 214 g of ethanol were charged and stirred vigorously for 30 minutes.

The pH of the mixed solution was 13. After tightening the lid of the autoclave, place it in an oil bath and keep the internal temperature at 1'05"C.
Hydrothermal synthesis was carried out for 120 hours while stirring at a rotation speed of 00 r, p, m or more. During this time, the pressure inside the autoclave reached 2-3 kg/cd. The pH at the end of the hydrothermal synthesis was 11.8. The white solid product was filtered off and then washed successively with distilled water until the pH of the filtrate was around 7. 500-53 after drying white solid
The mixture was calcined at 0° C. for 4 hours under air circulation to obtain 27 g of powdery white crystals. As a result of analyzing the crystal by powder X-ray diffraction,
It was identified as pentasil type zeolite. In addition, as a result of elemental analysis using atomic absorption spectroscopy, the St/A+ atomic ratio was 14.
It was 7000.

Add 100g of 5% ammonium chloride aqueous solution to this crystal log.
was added and subjected to ion exchange treatment at 50 to 60°C for 1 hour, followed by filtration. After performing this ion exchange treatment four times, the crystals were washed with distilled water until no CI- ions were detected. Subsequently, the crystals were dried at 120°C for 16 hours. The obtained ammonium salt type crystals were pressure-molded and then sieved into a 24-4B mesh. Further, the crystals were calcined at 500°C for 1 hour under nitrogen gas flow to obtain a catalyst. This catalyst is referred to as a catalyst.

Reference Example 2 (Preparation of Catalyst B) Tetraethyl orthosilicate (S i (OCzHs)-) 10 was placed in a 1.5 f stainless steel autoclave.
0 g, 224 g of a 10% aqueous tetra-n-propylammonium hydroxide solution, and 60 g of ethanol were charged and thoroughly stirred. Add 48g of aluminum sulfate aqueous solution (Alz(SO4)s・18H!0) to this mixed solution.
20 mg/48 g of water) was added and stirred vigorously for 30 minutes. Note that the pH of the mixed solution was 13. After tightening the lid of the autoclave, immerse it in an oil bath and keep the internal temperature at 105°C for 400 r.

Hydrothermal synthesis was carried out for 120 hours while stirring at rotational speeds of 1, 2, m or more. During this time, the pressure inside the autoclave reached 2-3 kg/ci. The pH at the end of the hydrothermal synthesis was 11.8. Reference example 1 is a white solid product.
It was calcined in the same manner as above to obtain powdery white crystals. As a result of analyzing the if crystal by powder X-ray diffraction, it was identified as pentasil type zeolite. Further, as a result of elemental analysis by atomic absorption spectroscopy, the Si/At atomic ratio was found to be 7000.

Thereafter, this crystal was ion-exchanged and calcined in the same manner as in Reference Example 1 to obtain a catalyst. This catalyst is called catalyst B.

Reference example 3 (preparation of catalyst C) First, a raw material liquid having the following composition was prepared.

Solution A: 162g of distilled water, 16.7g of sulfuric acid, Alt(SO
a) s18Hzo 2.92g.

(n-Pr) 4NB r 20. 8 g Solution B: 119.7 g of distilled water, 186.3 g of No. 3 sodium silicate Solution C: 281.7 g of distilled water, 70.7 g of sodium chloride Added solutions A and B to the above solution C simultaneously while stirring vigorously. did. The pH at the end of mixing was 9.6. The mixture was placed in a 1.52 stainless steel autoclave.
Hydrothermal synthesis was carried out at 160° C. for 20 hours with stirring at a rotational speed of 400 r, p, m or higher. After cooling, it was filtered, and washing and filtration were repeated sufficiently with about 72 ml of distilled water until no Ct- ions were detected. Further, the obtained white solid was dried at 120°C for 16 hours.Then, this crystal was calcined at 500 to 550°C for 4 hours under air circulation to obtain white powdery crystals. As a result of analyzing the crystals by powder X-ray diffraction, they were identified as pentasil type zeolite. Further, as a result of atomic absorption analysis of this crystal, the Si/At atomic ratio was 50.

Thereafter, this crystal was ion-exchanged and calcined in the same manner as in Reference Example 1 to obtain a catalyst. This catalyst is called catalyst C.

Reference example 4 (preparation of catalyst) First, a raw material liquid having the following composition was prepared.

Solution A; 443 g of distilled water, 45 g of sulfuric acid, (n-Pr) aN B r 55. 8 g B solution;
320 g of distilled water, 53 g of No. 3 sodium silicate Solution C; 754 g of distilled water, 89 g of sodium chloride To the above Solution C, Solutions A and B were simultaneously added dropwise and mixed with vigorous stirring. The pH at the end of mixing was 9.5.The mixture was charged into a stainless steel autoclave No. 31.
350r, p for 20 hours at 0°C.

Hydrothermal synthesis was performed while stirring at a rotation speed of -9 or more. After cooling, it was filtered, and washing and filtration were repeated sufficiently with distilled water of about 152 ml until CI ions were no longer detected.

The obtained solid was calcined in the same manner as in Reference Example 1 to obtain white powdery crystals. As a result of analyzing the crystal by powder X-ray diffraction,
It was identified as pentasil type zeolite. Further, as a result of atomic absorption analysis of the crystal, the Si/Al atomic ratio was found to be 100.

Thereafter, this crystal was ion-exchanged and calcined in the same manner as in Reference Example 1 to obtain a catalyst. This catalyst is called a catalyst.

Reference example 5 (preparation of catalyst E) First, a raw material liquid having the following composition was prepared.

Solution A: 150 g of distilled water, (n-Pr) 4N,
B r81g1 colloidal silica (31-30) 118
．． 8g Solution B; 150g distilled water, 76.5g sodium hydroxide Solution B was added dropwise to the above Solution A and mixed. 1 mixture! The mixture was placed in a stainless steel autoclave, and hydrothermal synthesis was performed while stirring at 160°C for 24 hours.

After cooling, it was filtered and washed continuously with distilled water until the pH of the filtrate was around 7.

The obtained white solid was calcined in the same manner as in Reference Example 1 to obtain powdery crystals. As a result of analyzing the crystals by powder X-ray diffraction, they were identified as pentasil type zeolite. Furthermore, as a result of atomic absorption analysis of this crystal, the Si/Al atomic ratio was 140.
It was 0.

Thereafter, this crystal was ion-exchanged and calcined in the same manner as in Reference Example 1 to obtain a catalyst. This catalyst is called catalyst E.

Reference Example 6 (Preparation of Catalyst F) A 10% aqueous solution of tetra-n-propylammonium hydroxide was placed in a 1.51 mm stainless steel autoclave.
5g, 214g of ethanol, 2d of aqueous solution containing 64.2cm of zirconium oxynitrate, 100g of high purity tetraethyl orthosilicate (Si(OCgHs)4)
were added in this order and thoroughly stirred for 1 hour. Hydrothermal synthesis was then carried out for 48 hours while maintaining the internal temperature at 105°C and stirring at a rotational speed of 400 r, p, m or more. The resulting white solid was filtered and washed continuously with distilled water until the pH of the filtrate was around 7. The obtained crystal was rotated at 120°
It was dried at C for 16 hours. Add 50 more of these dried crystals.
The mixture was calcined at 0 to 550° C. for 4 hours under air circulation to obtain 27 g of white powdery crystals. As a result of powder X-ray diffraction analysis of the crystals, it was identified as a zirconosilicate having a structure similar to that of pentasil-type zeolite. Further, as a result of atomic absorption analysis of the crystal, the Si/Zr atomic ratio was found to be 2,400.

Thereafter, this crystal was ion-exchanged and calcined in the same manner as in Reference Example 1 to obtain a catalyst. This catalyst is called catalyst F.

Reference Example 7 (Production of Catalyst G) A white powder was obtained by hydrothermal synthesis, filtration, and calcination in accordance with Reference Example 6, except that 1.414 g of titanium tetraisopropoxide was used in place of zirconium oxynitrate. As a result of analyzing the powder by powder X-ray diffraction, it was identified as a crystalline silicate having a structure similar to that of pentasil-type zeolite.

Further, as a result of atomic absorption analysis of the crystal, the Si/Ti atomic ratio was 90. Subsequently, ion exchange was performed in the same manner as in Reference Example 1, and the catalyst was calcined to obtain a catalyst. This catalyst is called catalyst G.

Reference Example 8 (Preparation of Catalyst H) Vanadium trichloride 30 instead of zirconium oxynitrate
．． A white powder was obtained by hydrothermal synthesis, filtration, and calcination according to Reference Example 6, except that 2■ was used. As a result of analyzing the powder by powder X171 diffraction, it was found that it was pentasil type zeolite and FA4Q.
It was identified as a crystalline silicate with the following structure. Also,
As a result of atomic absorption analysis of the crystal, the S i /V atomic ratio was 2300.

Subsequently, ion exchange and calcination were performed in the same manner as in Reference Example 1 to obtain a catalyst. This catalyst is called catalyst H.

Reference Example 9 (Preparation of Catalyst ①) In a 1.51 stainless steel autoclave, 45.0 g of Aerosil (high purity amorphous silica), 45.73 g of N-propylammonium bromide, and 10.8 g of sodium hydroxide were placed in a 1.51 stainless steel autoclave. After charging 375.81 g of distilled water and tightening the lid of the autoclave, the autoclave was vigorously stirred at 20°C for 120 hours. The pH of the mixed solution was 12.8.

Thereafter, hydrothermal synthesis was carried out for 96 hours while maintaining the internal temperature at 105° C. and stirring at a rotation speed of 400 r, p, m0 or more. The white solid product was filtered off and the pH of the filtrate
It was washed continuously with distilled water until the temperature was around 7. The white solid product was calcined in the same manner as in Reference Example 1 to obtain powdery white crystals. As a result of analyzing the crystals by powder X-ray diffraction, they were identified as pentasil type zeolite. Furthermore, as a result of atomic absorption analysis of the crystal, the Si/A+ atomic ratio was 360.

Thereafter, this crystal was ion-exchanged and calcined in the same manner as in Reference Example 1 to obtain a catalyst. This catalyst is called catalyst (2).

Reference Example 10 (Preparation of Catalyst J) 1.5! Tetraethyl orthosilicate (St(QCOHs) 4) 104.
17g, 10% aqueous tetra-n-propylammonium hydroxide solution 232.85g, ethanol 62.3g
3g of distilled water and 50.44g of distilled water were added and vigorously stirred for 30 minutes.

Note that the pH of the mixed solution was 12.5. After tightening the lid of the autoclave, it was immersed in an oil bath and hydrothermal synthesis was carried out for 96 hours while maintaining the internal temperature at 105°C and stirring at a rotation speed of 400 r, p or more. During this time, the pressure inside the autoclave reached 2-3 kg/c-.

The pH at the end of the hydrothermal synthesis was 11.7. The white solid product was calcined in the same manner as in Reference Example 1 to obtain powdery white crystals. As a result of analyzing the crystals by powder X-ray diffraction, they were identified as pentasil type zeolite.

Further, as a result of atomic absorption analysis of the crystal, the St/Al atomic ratio was 9000.

Thereafter, this crystal was ion-exchanged and calcined in the same manner as in Reference Example 1 to obtain a catalyst. This catalyst is called catalyst J.

Reference Example 11 (Preparation of catalyst) A white powder was obtained by hydrothermal synthesis, filtration, and calcination according to Reference Example 6, except that germanium tetraisopropoxide (98.9 cm) was used instead of zirconium oxynitrate. . As a result of analyzing the powder by powder X-ray diffraction, it was identified as pentasil type zeolite and a crystalline silicate having the structure of [(jl).In addition, as a result of atomic absorption analysis of the crystal,
The Ge atomic ratio was 1800. Subsequently, ion exchange was performed in the same manner as in Reference Example 1, and the catalyst was calcined to obtain a catalyst. This catalyst is called a catalyst.

Example 1 0.3 of catalyst A was placed in a quartz glass reaction tube with an inner diameter of 1 cm.
g (0,51d) and preheated at 350'C for 1 hour under nitrogen flow. Then cyclohexanone oxime/methanol/benzene weight ratio -1/2.3/11.5
A mixed solution of
r-', and the temperature of the catalyst layer (reaction temperature) was 350° C. One reaction product was collected every hour under water cooling and analyzed with a gas chromatograph.

Note that methanol was recovered with a recovery rate of 98% or more in all analyses.

The analysis results are shown in Table 1.

In Table 2, the space velocity WH3V is a value calculated using the following equation, and the reaction rate of cyclohexanone oxime and the selectivity of ε-caprolactam are calculated using the following equations.

W HS V (hr-') U hexanone oxime (Co-supply rate (kg/hr
) /M Charge fi (kg) Reaction rate of cyclohexanone oxime (%) - ((X-Y
) /

X - Number of moles of raw material cyclohexanone oxime supplied Y - Number of moles of unreacted cyclohexanone oxime Z - Number of moles of ε-caprolactam in the product Examples 2 to 9 The catalyst described in the reference example was prepared in the same manner as in Example 1. After heat treatment, the reaction was carried out using 0.3 g (0.5 m) of each, and the weight ratio of cyclohexanone oxime/methanol/benzene, the feeding rate of the mixed solution, and the reaction temperature were the same as in Example 1. It is shown in Table 2.

Table Comparative Examples 1 to 9 A mixed solution of cyclohexanone oxime/benzene weight ratio = 1/11.5 was prepared without methanol coexisting in the reaction system.
It was supplied to the reaction tube at a supply rate of 1.5 g/hr, and the reaction was carried out at a reaction temperature of 350°C. The rest was carried out in the same manner as in Example 1.

The reaction results are shown in Table 3.

Table 3 In order to confirm the reproducibility of catalyst preparation and cyclohexanone oxime rearrangement reaction, a catalyst was prepared again using the same method as Catalyst A of Reference Example 1 (this catalyst is hereinafter referred to as Catalyst A*.S
The i/A+ atomic ratio was 147,000. ), catalyst A*
0. The reaction was carried out under the same conditions as in Example 1 using 3 g (0,51R1).

The reaction results are shown in Table 4.

Table 4 Comparative Example 10 Using the same amount of catalyst A* as in Example IO, the reaction was carried out under the same conditions as in Comparative Example 1 without methanol coexisting in the reaction system.

The reaction results are shown in Table 5.

Example 10 Table 5 Example 11 The reaction was carried out in the same manner as in Example 1, except that benzene was not present in the reaction system. In addition, the same amount of catalyst A* as in Example 10 was used as a catalyst, and a mixed solution of cyclohexanone oxime/methanol weight ratio=1/2 (7) was mixed with 3. Og/h
The mixture was supplied to the reaction tube at a supply rate of r and allowed to react. W at this time
HS V is 3.3hr” and the reaction temperature is 350°
It was C.

The reaction results are shown in Table 6.

Table 6 Using * to the same amount of catalyst as in Example 10, a mixed solution of cyclohexanone oxime/methanol weight ratio -1/13 was added to 1
The mixture was supplied to the reaction tube at a supply rate of 1.7 g/hr for reaction. WH3V at this time is 2. Bhr-' and the reaction temperature was 350°C.

The reaction results are shown in Table 7.

Table 7 Examples 13 to 17 The reaction was carried out at the same feed rate and reaction temperature as in Example 1, except that the same amount of catalyst A* as in Example 10 was used and the alcohol shown in Table 8 was used instead of methanol. Ta.

The reaction results are shown in Table 8.

Example 12 Similar to Example 11, no benzene was used, and Example 1
8-19 Using the same amount of catalyst A* as in Example 10, the feed ratio of cyclohexanone oxime/methanol/benzene (heavy fit
), and the reaction was carried out using the same feed rate and reaction temperature as in Example 1.

The reaction results are shown in Table 9.

Example 20 Catalyst A* was placed in a quartz glass reaction tube with an inner diameter of 1.1.
A mixed solution of cyclohexanone oxime/methanol/benzene with a weight ratio of -1/1°1/10.4 was charged at 5.8 g/hr and preheated in the same manner as in Example 1. The mixture was fed to the reaction tube at a feeding rate and allowed to react. At this time, WH3■ is 0. 9 hr-' and the reaction temperature was 350°C.

The reaction results are shown in Table 1O.

Table 10 Example 21 Catalyst in a quartz glass reaction tube with an inner diameter of 1 cm! 0.3
Filled with 48g (0.58m) and heated at 350°C under nitrogen flow.
It was preheated for 1 hour.

Next, under a nitrogen stream (4.24!/hr), a mixed solution of cyclohexanone oxime/methanol weight ratio -1/1.86 was supplied to the reaction tube at a supply rate of 8.0 g/hr to cause a reaction. WH3V at this time was 8. 0 hr-' and the reaction temperature was 350° C. The reaction product was collected every hour under cooling with a dry ice-methanol solution and analyzed by gas chromatography.

The reaction results are shown in Table 11.

Table 11 Comparative Example 11 Toluene was coexisted in the reaction system instead of methanol, and a mixed solution of cyclohexanone oxime/toluene weight ratio -1/1.86 was supplied to the reaction tube at a supply rate of 8.0 g/hr, and the reaction temperature was 350. The reaction was carried out at ℃. WH3V at this time was 8. It was 0hr-1. The rest was carried out in the same manner as in Example 21.

The reaction results are shown in Table 12.

Table 12 Example 22 0.9 g of catalyst l was placed in a quartz glass reaction tube with an inner diameter of lCw.
(1,5rd) filled with 350 ml under reduced pressure (30 Torr)
The first one was preheated at °C for 1 hour and then the pressure was adjusted to 80 Torr.
A mixed solution of cyclohexanone oxime/methanol weight ratio=115 was supplied to the reaction tube at a feeding rate of 4.8 g/hr to cause a reaction. At this time, WH5V is 0
．． 9 hr-' and the reaction temperature was 350°C.
The reaction products were collected every hour under water cooling and analyzed using a gas chromatograph.

The reaction results are shown in Table 13.

Table 13 Comparative Example 12 Toluene was allowed to coexist in the reaction system instead of methanol, and a mixed solution of cyclohexanone oxime/toluene weight ratio of -115 was supplied to the reaction tube at a supply rate of 4.8 g/hr, and the reaction temperature was 350°C. I reacted with The rest was carried out in the same manner as in Example 22.

The reaction results are shown in Table 14.

Table 14 Comparative Example 13 The reaction was carried out in the same manner as in Comparative Example 12 except that Catalyst (■) was changed to Catalyst (J).

The reaction results are shown in Table 16.

Example 23 A reaction was carried out in the same manner as in Example 22, except that Catalyst (1) was changed to Catalyst (J).

The reaction results are shown in Table 15.

Table 15 Example 24 Catalyst A* was placed in a quartz glass reaction tube with an inner diameter of 1 cta at a concentration of 0. It was filled with 3 g (0,5I11) and preheated in the same manner as in Example 1. Then under air circulation (11/hr)
, 11.4 g/h of a mixed solution of cyclohexanone oxime/methanol/benzene weight ratio -115,6/9.9
The mixture was supplied to the reaction tube at a supply rate of r and allowed to react. W at this time
H3V is 3, Ohr-' and the reaction temperature is 35
It was 0°C.

The reaction results are shown in Table 17.

Table 17

Claims (1)

[Claims] 1. A method for producing ε-caprolactam from cyclohexanone oxime under gas phase reaction conditions using a solid acid catalyst, the method comprising allowing a lower alcohol to coexist in the reaction system.