JP2856383B2 - Methylamine production using shape-selective chabazite - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing methylamine from methanol or dimethyl ether and ammonia using a microporous composition as a catalyst.

[0002]

BACKGROUND OF THE INVENTION The reaction of methanol and ammonia to produce methylamine, which is a mixture of mono-, di- and trimethylamine, is a well-known reaction. 350 ° C temperature, 1
Atmospheric pressure and an ammonia to methanol ratio of 3.5 (N /
R), the reaction product is about 35% by weight of monomethylamine (MMA), 27% by weight of dimethylamine (DM
An equilibrium mixture consisting of A) and 38% by weight of trimethylamine (TMA). Substantial process attempts have been made with product candidates (pr.
oduct slate). Process variables affecting product candidates include, but are not limited to, time, ammonia to methanol molar ratio and temperature. The change of the product candidates is mainly performed using a shape-selective catalyst such as zeolite.

Representative patents describing various processes for the production of methylamine reaction products having non-equilibrium amounts of MMA, DMA and TMA by the reaction of methanol with ammonia are as follows: US Pat. No. 485,261 introduces a mixture of methylamine and ammonia into a porous solid acid catalyst consisting of silica, alumina, Y and X zeolites, thereby producing an initial reaction product and then the reaction product A methylamine reaction product rich in DMA and low in TMA, comprising subjecting at least a part of the reaction product to a catalytic reforming reaction in the presence of ammonia and a crystalline aluminosilicate having a pore size of 3 to 8 °. Is disclosed. Various catalysts having a pore size of 3 to 8 mm are described, and these catalysts include clinoptilolite, erionite,
Includes mordenite, chabazite and various synthetic zeolites. US Patent 4,2
No. 05,012 describes a process for the preparation of amines by the reaction of alkanols and ammonia, such as FU in which essentially all sodium cations are replaced by divalent or trivalent cations.
Discloses the production of methylamine by the reaction of methanol and ammonia in the presence of -1 zeolite.

US Pat. No. 4,602,112 discloses acidic H-
Disclosed is a method for producing DMA with high selectivity by reacting methanol or dimethyl ether with ammonia in the presence of a ZSM-5 zeolite catalyst.

US Pat. No. 3,384,667 discloses a dehydrated, naturally occurring crystalline aluminosilicate catalyst having a pore size that absorbs primary and secondary amine products but not tertiary amine products. Disclosed below is the alkylation of ammonia. Examples of natural zeolites include ferrierites, chabazite, erionite and mordenite.

US Pat. No. 4,737,592 each discloses a geometric selectivity in greater than about 3.
dex; GSI) to produce a DMA-rich reaction product by the reaction of methanol and / or dimethyl ether with ammonia in the presence of an acidic zeolite catalyst selected from the group consisting of natural H-exchanged and M-exchanged chabazite. A method is disclosed. Alkali metal ions suitable for exchange include sodium, potassium, rubidium and cesium.

US Pat. Nos. 4,458,092 and 4,3
Nos. 98,041 and 4,434,300 disclose a process for producing methylamine by reaction using a zeolite type catalyst. U.S. Pat. No. 4,458,092 discloses the use of rare earth exchanged highly acidic dehydrated aluminosilicate catalysts or Y-zeolites in which hydrogen has been exchanged for metal ions. US Patent No. 4,434,300
Discloses the preparation of amines using large porous H-chabazite-erionite as the preferred amination catalyst. Anaconda chabazite-erionite was used as the specific catalyst, and the catalyst system achieved high methanol conversion with minimal TMA formation.

US Pat. Nos. 4,254,061 and 4,313,003 each disclose MMA (the '061 patent).
And the preparation of methylamine rich in DMA ('003 patent). The '061 patent discloses the reaction of methanol with ammonia in the presence of mordenite, erionite, clinoptilo lit, etc. to produce MMA, while the' 003 patent discloses the catalyst of the '061 patent. Reacting MMA with ammonia in the presence of DM
It discloses the production of A-rich reaction products.

US Pat. No. 4,082,805 discloses ZSM-
5, the presence of ZSM-11 or a crystalline aluminosilicate having a ZSM-21 structure, C ₁ -C ₅ - discloses the preparation of amines by reaction of an alcohol or ether with ammonia.

[0010]

The present invention provides a non-equilibrium amount of TM
An improved process for preparing a methylamine reaction product having A. One of the basic processes for producing a methylamine reaction product with good conversion of methanol / dimethyl ether and reduced trimethylamine content is to convert methanol / dimethyl ether to ammonia, monomethylamine, dimethylamine and dimethylamine in the presence of a zeolite-based catalyst. Reacting with trimethylamine. Alternatively, another method of producing a reaction product enriched in methylamine relies on the reforming of a monomethylamine-containing feedstock over a catalyst.
Some of the improvements in the basic process for the production of reaction products in which the amount of trimethylamine is reduced and the conversion of methanol / dimethyl ether is good are the shape selectivities (sh
ape selectivity index (SSI), the use of a zeolite having a GSI of less than 3 and a 1-propanol sorption value of greater than 0.5 mmol / g, preferably a zeolite catalyst consisting essentially of chabazite. . Shape selective zeolites or synthetic chabazite are typically exchanged for alkali metal ions such as sodium, potassium, rubidium and cesium. A second part of the improvement in the basic process consists in passing a feed containing monomethylamine over such a catalyst, thereby reforming such monomethylamine to a dimethylamine-rich product candidate.

There are several significant advantages that can be achieved by using zeolites and synthetic chabazite having SSI and propanol sorption rates as described above, and examples of these advantages include: trimethylamine A reduced amount of mono- and dimethylamine-rich reaction products can be produced; methylamine can be produced by amination of methanol with good conversion; methylamine with good methanol conversion A reaction product having a non-equilibrium fraction of mono, di and trimethylamine distribution can be produced; amination of methanol for a considerable time without deactivation of the catalyst The process can be performed; and It can result in product candidates of nonequilibrium recirculated monomethylamine containing feedstock over the catalyst with.

One of the basic routes for producing alkylamines is by amination of alkanols and alkyl ethers. The route of production of methylamine generally depends on the available materials and the desired product candidates under conditions sufficient to effect the amination.
H) and / or reacting dimethyl ether (DME) with ammonia, monomethylamine (MMA), dimethylamine (DMA) or trimethylamine (TMA). Typically, the nitrogen / carbon (N / R) molar ratio is in the range of about 0.2 to about 10, preferably 1 to 5, and the reaction temperature is about 225C to 450C, preferably 250C. ３375 ° C. The reaction pressure may vary, but at a total feed space velocity of about 200-8000 hr ^-1 , preferably 500-5000 hr ^-1
Typically 50-1000 psig, preferably 150-5
Within the range of 00 psig. "Space velo
The term "city)" or GHSV is defined as the ratio of gas feed rate (cm ³ ) to catalyst bed volume (cm ³ ) at STP / hr.

The conversion of methanol and / or DME to methylamine is generally about 50% to 100% (based on moles of methanol), the overall selectivity to methylamine is greater than 95% by weight, and Low TMA is 2
0% by weight or less, generally less than 15% by weight. Typically, the weight percentage of MMA in the reaction product is 36-50% by weight and the D
The weight percentage of MA is 25-60% by weight.

Another suitable feedstock for carrying out the process is that comprising monomethylamine. Monomethylamine is reformed on the catalyst to a dimethylamine-rich product candidate. Optionally, ammonia and other components such as trimethylamine may be present in the feed. However, the incorporation of trimethylamine into the feed does not show the distinct advantages of the product candidates.

The key to the amination process that results in low TMA production, high conversion and excellent conversion has a geometric selectivity (GSI) of less than 3, a shape selectivity (SSI) of greater than about 5, and 1 g of catalyst. At least about 0.5 per
It consists in using a catalyst system containing a microporous catalyst that sorbs millimoles of 1-PrOH (3% by weight of 1-PrOH). A preferred catalyst system consists of synthetic chabazite having an SSI of about 7-25. The term “shape selectivity (SSI)” is defined by the following equation: SSI = 20 ° C. and 0.5
Divided by the amount of 1-PrOH sorbed by the amount of 2-PrOH sorbed by the catalyst over a period of 24 hours at a relative pressure P / P ₀ . The sorption rate is expressed in weight%, i.e. in grams of sorbate per 100 g of zeolite catalyst.

Many of the conventional methods in which amination of methanol is carried out in the presence of a chabazite catalyst system use naturally occurring chabazite. The secret to the success of natural chabazite is US Patent 4,7
No. 37,592, the geometric selectivity (G
SI), where the GSI must be greater than about 3. The geometric selectivity was determined by the following equation: GS
1-P measured by exposure to sorbent vapor for 20 hours at I = 25 ° C. and relative pressure P / P ₀ of 0.1-0.5
The value obtained by dividing the net sorption amount of methanol (MeOH) by the net sorption amount of rOH (n-PrOH). The sorption rate is expressed in% by weight, i.e. in grams of sorbate per 100 g of zeolite.

It has been found that GSI is not at all predictable in determining the effectiveness of a catalyst in terms of selectivity or activity. In particular, synthetic chabazite catalysts do not follow this selectivity and activity parameter. It has been found that the activity and shape selectivity of zeolites as catalysts, especially chabazite, can be more accurately predicted using a parameter called shape selectivity (SSI) and other related 1-propanol sorption rates. SSI can assign the size and shape of a hole opening or cavity, while GSI evaluates cavity size using molecular packing. As the SSI value increases, the size and / or shape of the microporous structure preferentially excludes 2-PrOH over 1-PrOH to a significant extent.

SSI uses the branched-chain alcohol 2-PrOH as opposed to the straight-chain alcohol,
It accounts for both effects, but emphasizes the size and shape of the catalyst pore openings much more than the cavities. GS
Since I uses a linear alcohol in its measurement, it is more useful to assess how molecules fill into the microporous cavity and reactants or products from within the cage structure of the catalyst. Shows no ability to penetrate objects.
The correlation between these two concepts is evident when the catalysts differ by the size of the cavity due to cation occupancy or lattice constant changes.

The requirement for the catalyst to minimize the 1-propanol sorption value is due to the high methanol conversion of the catalyst, eg, 50% at operating temperature and space velocity.
The above gives a measure of the ability to achieve a conversion that generally results in a conversion of 75% or more. Catalysts with high SSI or GSI, but with low propanol sorption, give shape selectivity, but also generally show poor methanol / dimethyl ether conversion.

The metal cations in the zeolite structure affect both the SSI and activity of the catalyst. Large metal cations limit the sorption capacity of the zeolite framework and reduce its ability to sorb 2-propanol.
Cations such as H, for example, are not located within the framework of the zeolite or do not occupy sufficient spacing, resulting in an equilibrium distribution of zeolite and methylamine with low SSI values. The cation should be selected such that the zeolite or chabazite has an SSI within the preferred ranges and an acidity sufficient to maintain activity. Representative cations that can be used include H, Li, Na,
K, Rb, Cs, Mg, Ca, Ba, Al, Ga, F
e, Sr, La, Cu, Zn, Ni, B, Ce, Sn and Ru. Of these, alkali metal K
And Na are preferred.

Methods for producing such chabazite materials are known and are disclosed, for example, in US Pat. No. 4,925,460, which is incorporated herein by reference. After production, the chabazite is preferably heated to a temperature of at least 375 ° C. to calcine the catalyst system. Both unfired and calcined catalyst systems can be used to perform the methanol amination step,
The calcined chabazite provides a higher methanol conversion than the uncalcified chabazite catalyst system, and the calcined synthetic chabazite catalyst system provides a further reduced amount of TMA.

For all shape-selective catalysts, there is the potential to "exceed" the shape selectivity provided by the catalyst.
When that happens, the product candidates approach an equilibrium distribution. Shape selectivity decreases as catalysis changes from a zeolite cavity network to surface catalysis. There are many factors that can result in an equilibrium distribution of the methylamine product with a shape-selective catalyst, including extreme temperatures, low space velocities, and coking of the catalyst. In particular,
The reaction temperature is an important means for changing the product candidates from those having a shape-selective distribution to those having an equilibrium distribution. Various embodiments of the present invention are described in detail using the following examples and compared with the prior art. Unless otherwise specified, all percentages are expressed as weight percentages.

[0023]

【Example】

Example 1 Preparation of Synthetic Potassium Chabazite Potassium chabazite samples were prepared according to the general procedure described in Coe and Gaffney, US Pat. No. 4,925,460. More specifically, 48 g of an ammonium-Y zeolite, an LZY62 extrudate from UOP, were calcined at 500 ° C. for 2 hours, then cooled and wetted. Next, 189 g of colloidal silica (14% Si
O _2), and added to the premix solution of 1M KOH in 672Ml, and digestion. Nine such digestions were performed simultaneously in separate Nalgene bottles. The mixture was held at 95-100 ° C for 96 hours. The solid was collected and washed with deionized water until pH 7. Elemental analysis gave the following composition as weight percent oxide: 17.80% K ₂ O, 0.02% Na ₂ O,
24.30% Al ₂ O ₃ and 56.50% SiO ₂ .
The volume Si / Al ratio is 1.97 and the frame structure Si / Al ratio is 2.4 by ²⁹ Si MAS NMR.
Met. X-ray diffraction spectroscopy showed that the product was free of any Y-zeolite contaminants and was spectroscopically pure chabazite. The ratio of (K + Na) to the total Al content is about 8
It was shown that 0% of Al was in the zeolite framework.

[Example 2]
Manufacture of Na-chabazite An ammonium-exchanged chabazite sample was prepared using K
-Produced by ion exchange of a portion of chabazite sample. hydration
30% by weight of K-chabazite_FourNO_Three1 g in solution
Of chabazite in a proportion of 2 ml of solution, then 95-10
Heat to 0 ° C., hold for 2 hours, and collect and decant solid
Washed thoroughly with deionized water. This replacement and cleaning operation
Repeated five more times. After drying at 110 ° C., 450
g of NH _FourThe chabazite product was recovered. The remaining K is about 11
% Ion exchange capacity.

Example 3 95% potassium exchanged
Preparation of Synthetic Chabazite Potassium-exchanged chabazite sample was prepared using NH prepared in Example 2._Four
-Produced by ion exchange of a portion of chabazite sample. 30
g of dry NH_Four-Moisten chabazite, 300 ml of 1M
KNO_ThreeAdd to the solution at 95-100 ° C over 2 hours,
The solid was recovered and washed with deionized water. This exchange
The washing operation was repeated once more. Elemental components of the product
The analysis gave the following composition as weight percent of oxide: 17.1
7% K_TwoO, less than 0.02% Na_TwoO, 24.6% A
l_TwoO_ThreeAnd 56.60% SiO _Two. The K component of the sample is about
It had an ion exchange capacity of 94.5%.

Example 4 Preparation of 58% Sodium-exchanged Synthetic Chabazite A sodium-exchanged chabazite sample was prepared using NH prepared in Example 2.
_{The 4-} chabazite sample was produced by ion exchange. 5
Wet 0 g of dry NH ₄ chabazite and add 300 ml of 1M
Added to the NaNO ₃ solution at 95-100 ° C. over 2 hours,
The solid was then collected and washed with deionized water. This exchange and washing operation was repeated once more. Elemental analysis of the product gave the following composition as% by weight of oxide: 1.3
2% K ₂ O, 7.63% Na ₂ O, 27.20% Al
₂ O ₃ and 64.20% SiO ₂ . Na and K of sample
The components had ion exchange capacities of about 57.5% and 6.5%, respectively.

Example 5 Production of Synthetic Chabazite Exchanging More Than 99% of Sodium A sodium-exchanged chabazite sample was prepared from NH prepared in Example 2.
_{The 4-} chabazite sample was produced by ion exchange. 3
Wet 0 g of dry NH ₄ chabazite and add 1000 ml of 1
Added over 2 hours at 95 to 100 ° C. in M NaNO ₃ solution, then the solid was collected and washed with distilled deionized water. This exchange and washing operation was repeated five more times.
Elemental analysis of the product gave the following composition as weight percent of oxide: 0.05% K ₂ O, 12.66% Na ₂ O, 2,
5.80% of Al ₂ O ₃ and 61.20% of SiO _2. The Na and K components of the sample were slightly over 99% and 0.
It had an ion exchange capacity of 5%.

Example 6 Preparation of 66% Sodium-Exchanged Synthetic Chabazite Preparation of sodium-exchanged chabazite involved three steps. These steps are as follows: A potassium chabazite sample was prepared according to the general procedure of Example 1. The resulting 160 g LZY64 extrudate was calcined at 500 ° C. for 2 hours, then cooled and wetted. Next, the wet extrudate was added to a premixed solution of 630 g of Nalco® 2326 colloidal silica (14% SiO ₂ ) and 2240 ml of 1 M KOH and cooked. Three such digestions were performed simultaneously in separate Nalgene and bottles. The mixture was held at 95-100 ° C for 96 hours. The solids were collected, coalesced and washed with deionized water until pH 7, then dried at 110 ° C. (K +
The ratio of Na) to the total Al content indicated that 84% of the Al was in the zeolite framework.

B. Step A of ammonium exchanged chabazite sample
The K-chabazite sample synthesized by the above was manufactured by ion exchange. Moisten 50 g of dried NH ₄ -chabazite,
95-100 ° C. in 125 ml of 30% by weight NH ₄ NO ₃ solution
For 2 hours, then the solid was collected and washed thoroughly with deionized water. This replacement and cleaning operation is performed for an additional 5 minutes.
Repeated times.

C. Sodium exchanged chabazite was prepared by ion exchange of an NH ₄ -chabazite sample prepared according to Step B. All the hydrated NH ₄ -chabazite was added to 300 ml of a 1 M NaNO ₃ solution at 95-100 ° C. for 2 hours, then the solid was collected and washed with deionized water. This exchange and washing operation was repeated once more. Elemental analysis of the product gave the following composition as weight percent of oxide:
0.28% K ₂ O, 8.46% Na ₂ O, 25.20%
Al ₂ O ₃ and 66.10% SiO ₂ . The Na and K components of the sample had an ion exchange capacity of about 66% and 1.4%, respectively.

Example 7 Preparation of Potassium-Exchanged Synthetic Chabazite A potassium chabazite sample was prepared according to the cooking process of Example 6, except that a different lot of LZY64 was used. [Example 8] Production of 80% sodium-exchanged synthetic chabazite A sodium-exchanged chabazite sample was prepared from K-
Manufactured by ion exchange of a portion of the chabazite sample. 50g
Dry K-chabazite, 1665 ml of 1M N
ANO ₃ solution was added over a period of 2 hours at 95 to 100 ° C., then the solid was collected and washed with deionized water. This exchange and washing operation was repeated once more. Elemental analysis of the product gave the following composition as weight percent of oxide: 3.76
% K ₂ O, 10.02% Na ₂ O, 24.40% Al
₂ O ₃ and 62.00% SiO ₂ . Na and K of sample
The components had about 80% and 20% ion exchange capacity, respectively.

Example 9 Production of 99% Sodium-exchanged Synthetic Chabazite A sodium-exchanged chabazite sample was prepared from K-
Manufactured by ion exchange of a portion of the chabazite sample. 50g
Dry K-chabazite, 1665 ml of 1M N
ANO ₃ solution was added over a period of 2 hours at 95 to 100 ° C., then the solid was collected and washed with deionized water. This exchange and washing operation was repeated five more times. Elemental analysis of the product gave the following composition as weight percent of oxide: 0.23
% K ₂ O, 12.37% Na ₂ O, 24.50% Al
₂ O ₃ and 62.80% SiO ₂ . Na and K of sample
The components had about 99% and 1% ion exchange capacity, respectively.

Example 10 Calcination of Ammonium-Exchanged Synthetic Chabazite The ammonium-exchanged chabazite sample produced in Example 22 was calcined at 350 ° C. in air. The dried product from Example 2 was placed in a muffle furnace at 110 ° C. and then ramped at about 5 ° C./min to 350 ° C. where it was held for 2 hours. Elemental analysis of the calcined product gave the following composition as weight percent oxide:
2.46% K ₂ O, 0.02% Na ₂ O, 29.20%
Al ₂ O ₃ and 68.30% SiO ₂ .

[Examples 11 to 15] Calcination of cation-exchanged synthetic chabazite Samples of the cation-exchanged chabazite produced in Examples 4, 5, 6, 8 and 9 were respectively subjected to the general method of Example 10. It was fired at 450 ° C. according to the procedure. Table 1 shows the processing steps.

[0035]

[Table 1]

Examples 16-21 Geometric Selectivity and Shape Selectivity Several catalysts were measured for GSI and SSI according to the sorption method. More specifically, GSI is 2 ° C at 20 ° C.
Determined by measuring the sorption of methanol and 1-PrOH of the catalyst system when exposed to sorbent vapor for 0-24 hours. Measurement of geometric selectivity (GSI) is described in U.S. Pat.
The general procedure of 737,592 was followed. For shape selectivity (SSI) measurements, each catalyst sample was degassed in situ, raised to a temperature of 400 ° C. at a rate of 1 ° C./min, and held under a vacuum of 0.1 mTorr for 10-12 hours. Each catalyst sample was then cooled to 20 ° C. and exposed to the respective vapor at a relative pressure (P / P ₀ ) of 0.5 for about 24 hours. The sorption temperature of methanol, 1-PrOH and 2-PrOH was 20 ° C. The order of sorption for each catalyst system was 2-PrOH, 1-PrOH and methanol. After each exposure to the sorbent vapors, the test catalyst was degassed under vacuum at 400 ° C. overnight, and the catalyst samples were weighed to ensure that all sorbent vapors had been removed. If some sorbent vapor remained and did not reach the original dry weight of the catalyst system, the test catalyst was degassed again.
The corresponding index was calculated.

Table 2 below shows the synthetic and natural catalyst systems and their corresponding GSI and SSI values. Natural chabazite is used only as an illustration.
With respect to their intrinsic properties, minerals differ not only between natural deposits but also within one deposit.

[0038]

[Table 2]

Example 22 Amination of Methanol Using Chabazite Catalyst Amination of some methanol was carried out by reacting methanol with ammonia using various catalyst systems. Table 3 shows the origin and reaction conditions for the catalyst,
Table 4 shows the results of each reaction.

[0040]

[Table 3]

[0041]

[Table 4]

For comparison, FIG. 3 shows the geometric selectivity (GSI) versus the TMA selectivity for the synthetic chabazite catalyst. The plot shows that good selectivity and activity with respect to the production of methylamine can be achieved with low GSI.
Thus, SSI is a more useful parameter for the performance of the base catalyst.

Experiments 1 and 4 show the effect of cationic unfired catalyst on methanol conversion and TMA selectivity. Experiments 4 and 6 with a degree of cation exchange of more than 99%
This shows that the higher SSI value of the Na cation form gives higher conversion than the K cation form (Experiment 2). The Na and K exchanged catalysts have about 22 and 23 S, respectively.
It has an SI value and gives a TMA selectivity well below the equilibrium value of 35% by weight. The catalyst gave a GSI value lower than 3. As described above, when the SSI values are the same, the difference in the conversion rate reflects not the diffusion resistance of the pore but the type of the cation.

Experiments 1 and 2 show that the methanol conversion of the K cation type can be increased by partially exchanging NH ₄ ⁺ with K ⁺ even if the GSI is lower than 3. An S greater than about 7 for these unfired catalysts
By maintaining the SI value, the TMA selectivity remains very low. This effect was also seen for the Na cation form by comparing experiments 3 and 4 with TMA
Remains below 35% by weight, but the conversion has increased from 76% to 94%.

Runs 7 and 8 for 99% Na chabazite show that SSI values lower than 3 are undesirable in methylamine synthesis. Run 8 used a catalyst with a 1-PrOH sorption capacity of less than 0.5 mmol / g. In this case, the low SSI value results from significant elimination of both 1-PrOH and 2-PrOH, but the GSI of about 6 indicates that methanol is still very accessible. According to the prior art, this is an acceptable catalyst because its TMA selectivity is only 1% by weight, indicating that its activity is still dominated by the inner surface of the zeolite. However, its conversion (34%), ie less than 50% at 350 ° C., is ineligible.

Experiments 3 and 5, and 4 and 6, show the effect of firing. In experiments 3 and 5, unfired and fired 58% N
a The GSI value of chabazite remains below 3, but SSI increased from 7 to 9 by calcination reduces TMA selectivity from 33% to 15% by weight. On the other hand, the conversion increased from 94% to 98%. Experiment 3 shows that the unfired catalyst is very active but has less selectivity for TMA than the fired type. At very high SSI values, for example, greater than 25, the diffusion resistance of the pores is a measure of the conversion and TM
It limits both A selectivity, catalysis is limited to surface catalysis, and product candidates are expected to approach those of the equilibrium distribution. In experiments 4 and 6, the catalyst had more than about 99% Na of its ion-exchangeable cations, its SSI values were 22 and 15, respectively, and calcination at 450 ° C. resulted in a conversion or TMA selectivity. Has little or no effect.

Runs 5, 6 and 7 show the effect of cation exchange on a series of calcined catalysts having GSI values lower than 3 and SSI values in the range of 7-15. When the Na cation exchange is reduced from 99% to 66%, the conversion is 73%.
To 99% and TMA selectivity from 4% to 13% by weight.
Weight percent. In addition, the Na exchange was reduced from 66% to 58
%, There is no improvement in conversion under the above process conditions and the TMA selectivity increases slightly from 13% to 15% by weight.

FIGS. 1 to 3 were prepared on the basis of data obtained from the above experiments in order to evaluate SSI as a means for predicting a product candidate for amination. Figure 1 shows Table 3.
FIG. 5 is a plot consisting of a plot of the data from FIGS. It shows that for many chabazite catalysts there is no correlation between SSI and GSI. FIG. 2 shows the SSI and T
5 is a plot of MA selectivity and SS in TMA selectivity for both calcined and unburned chabazite catalysts.
This shows the opposite effect of I. From FIG. 2, it can be seen that as the SSI value increases, the size and / or shape of the microporous structure preferentially excludes 2-PrOH over 1-PrOH to a greater extent. Thus, a green catalyst having an SSI of about 7 or greater gives a TMA selectivity of 35% by weight or less. Calcined catalysts having an SSI of about 3 or greater give similar results.

Example 23 Amination of methanol:
Comparative and Base Treatment Experiments For comparison, a series of methanol aminations were performed by reacting methanol with ammonia using various catalyst systems.

Base treated chabazite was prepared by placing a 20 g sample of K-chabazite in 200 ml of 0.5 M KOH and heating to 100 ° C. for 2 hours without stirring. The solution flowing out of the solid was washed with deionized water for about 5 minutes.
The process was repeated, except that the mixture was kept at 100 ° C. for 16 hours. After washing with distilled water and drying, the sample was analyzed to find 21.2% Al ₂ O ₃ , 57.7% Si
It was found containing O ₂ and 17.37% of K ₂ O.

The sample was then wetted by placing it in a closed vessel equipped with a water-filled Petri dish for 16 hours. The sample was placed at 100 ° C. for 1 hour with 30% NH ₄ Cl (10 m
l / g) three times. After each treatment, the sample with H ₂ O 10
Washed for minutes. The exchanged sample was dried at 110 ° C. and calcined at 450 ° C. for 2 hours.

Table 5 shows the origin of the catalyst and the results of each reaction. Unless otherwise noted, all experiments were 35
Performed at 0 ° C., GHSV = 1000 hr ⁻¹ , N / R = 3.5 and pressure = 250 psig.

[0053]

[Table 5]

Experiments 1 and 2 in Table 5 show that amorphous silica
Comparative data is shown for an alumina catalyst and H-type AW500 natural chabazite. The H-type natural chabazite has a high 1-PrOH sorption rate of 2.39 mmol / g. Therefore,
Although this data shows that the natural chabazite in form H gives an improved conversion over amorphous catalysts (which are more active) or certain synthetic chabazite at GSI lower than 3 and SSI lower than 5, experiments 1 Gives the same TMA selectivity as that of the amorphous catalyst.

Experiments 2 and 3 in Table 5 are comparative examples showing that similar high conversions and non-selective methylamine distributions are obtained for both the natural and synthetic chabazite of form H. No shape selectivity has been introduced. Runs 4 and 5 use a shape-selective H-type base treatment catalyst.
It has H ⁺ ions located in the framework for increased reaction and shape selectivity.

The calcined synthetic chabazite having an SSI of 5 to 25 gave the highest methanol conversion and essentially the lowest TMA selectivity. In contrast, GS greater than 3
Chabazite with I was effective but not catalytically active.

In particular, the importance of SSI values, whose number is greater than about 5, demonstrates the importance of SSI with respect to methanol / dimethyl ether conversion and TMA selectivity.
For example, in synthetic chabazite having an SSI near the lower end of the range, for example, unfired synthetic chabazite, the TMA selectivity is substantially increased, and the catalyst remains highly active.

Example 24 Modification of Monomethylamine Feedstock The procedure of Example 23 was repeated except that methanol was replaced by a feedstock containing monomethylamine as the feedstock. One feed contained about 30% monomethylamine in ammonia and the other contained pure monomethylamine. The catalyst used for the reaction was a hydrogen / potassium exchange chabazite similar to the base treated chabazite of Example 23. Table 6 shows the reaction conditions and results.

[0059]

[Table 6]

The above results show excellent conversion of monomethylamine to dimethylamine and excellent selectivity on chabazite catalyst. The results show that the addition of ammonia to the monomethylamine feed did not significantly reduce the conversion.

[Brief description of the drawings]

FIG. 1 is a plot showing the correlation between SSI and GSI for a number of chabazite catalysts, including calcined and uncalcined catalysts.

FIG. 2. For both calcined and unburned chabazite catalysts,
9 is a plot showing a relationship between a shape selectivity (SSI) and a TMA selectivity.

FIG. 3 is a plot of geometric selectivity (GSI) versus TMA selectivity for a synthetic chabazite catalyst as compared to a natural chabazite catalyst.

──────────────────────────────────────────────────の Continued on the front page (72) Inventor Thomas Richard Gaffney, Pennsylvania, USA 18103. Allentown. Clear View Circle 1211 (72) Inventor Gene Evelard Paris 1853. Pennsylvania, USA. Revere. Brownstone Road. P.O. Box 21 (72) Inventor Brent Allen Aufdemblink 18229, Pennsylvania, USA. Jim Thorpe. Porter Drive 1064 (58) Field surveyed (Int. Cl. ⁶ , DB name) C07C 209/00-211/65 B01J 29/04 C07B 61/00 300

Claims (6)

(57) [Claims] 1. A presence of microporous catalyst, monomethylamine by catalytic reaction between the feedstock and the ammonia consisting of methanol and dimethyl ether, a process for the preparation of non-equilibrium mixture of methylamines comprising dimethylamine and trimethylamine, from 3 small geometric selectivity, less the shape selectivity of <br/> and also 5 and at least 0.5 mmole /
increase the methanol or dimethyl ether conversion by using a catalyst having 1 g of 1-PrOH sorption,
The above method wherein the formation of trimethylamine in the methylamine reaction product is reduced. 2. The process of claim 1 wherein the microporous catalyst consists essentially of synthetic chabazite and methanol and ammonia are used in the reaction. 3. The method according to claim 1 , wherein the reaction is carried out at a temperature in the range of 250 to 375 ° C. and an N / R ratio of 0.2 to 10 . 4. The cation in the synthetic chabazite is H, Li, N
a, K, Rb, Cs, Mg, Ca, Ba, Al, Ga,
Fe, Sr, La, Cu, Zn, Ni, B, Ce, Sn
The method according to claim 2 , which is a mixture of cations selected from the group consisting of and Ru. 5. A calcined chabazite catalyst having an SSI in the range of 7-25, and the reaction is carried out at a temperature of 250-375 ° C., a pressure of 150-500 psig, a N / R of 1-5.
The method of claim 1, wherein performed in GHSV of and 500~5000hr ^-1. 6. A process for producing a mixture of monomethylamine, dimethylamine and methylamine containing trimethylamine by catalytic reforming of a feedstock containing monomethylamine in the presence of a catalyst, wherein the geometric selectivity is less than 3 .
And by performing the reforming in the presence of a microporous catalyst also has a 1-PrOH sorption rate of 0.5 mmol / g is also 5 a shape selectivity and less of less generation of trimethylamine in the reaction product The method as defined above.