JPS646817B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a catalyst for converting organic compounds and a method for converting organic compounds using the same.
In particular, it relates to a catalyst with a novel composition that methylates toluene to produce p-xylene with high selectivity, and a method for using the same. Production of p-xylene from toluene and methylating agents such as methyl alcohol; Production of olefins from methyl alcohol, dimethyl ether, etc. in the presence of aromatic compounds such as benzene and toluene; Disproportionation of alkylbenzenes such as toluene; Mixed xylenes Isomerization of dialkylbenzene to p-dialkylbenzene; Various catalysts are always used in reactions such as: Among these reactions, when producing p-xylene, which is an extremely useful raw material industrially, by methylation of toluene, a molecular sieve such as ZSM-5 zeolite with distributed micropores of a certain size and shape is used. It is known that when a functional crystalline aluminosilicate is used as a catalyst, p-xylene is produced with high selectivity. In addition, if aluminum, which is a skeletal element in this crystalline aluminosilicate, is replaced with other metals such as chromium, beryllium, and titanium, it is possible to isomerize o-, m-xylene or disproportionate toluene, resulting in an overall p - It is known to improve the selectivity of xylene (see JP-A-55-7598). However, none of the above-mentioned catalysts has a sufficiently high selectivity for p-xylene and is still unsatisfactory, and furthermore, they have the disadvantage that their catalytic activity deteriorates in a relatively short period of time. The present invention eliminates these drawbacks and provides a catalyst and a novel composition that are useful in conversion reactions of various organic compounds, and in particular can significantly improve the selectivity of p-xylene when used in toluene methylation reactions. The purpose is to provide instructions on how to use it. The catalyst of the present invention is characterized by comprising a phosphorus compound supported on crystalline borosilicate, and the conversion method of the present invention is characterized by bringing an organic compound into contact with the phosphorus-supported catalyst under conversion conditions. It is. First, the catalyst of the present invention has a skeleton of crystalline borosilicate, which will be described later, and supports a phosphorus compound, which will be described later. As crystalline borosilicate, for example, JP-A-53-
55500, JP 55-7598, JP 56
Examples include those described in JP-A-84313, JP-A-57-123817, JP-A-57-129820, and the like. Among these crystalline borosilicate, for example, ammonium type ones are generally prepared by the following method. That is, first, an aqueous solution (solution A) containing boric acid, concentrated sulfuric acid, and tetrapropylammonium bromide, silicon dioxide,
Aqueous solution of water glass consisting of sodium oxide and water (solution B) and aqueous sodium chloride solution (solution C)
After preparing each solution, solution A and solution B are added dropwise to solution C and mixed. If necessary, the pH of this mixture is adjusted to 9 to 10, and the temperature is 100% under self-generated pressure.
Heat in an autoclave at ~200 °C.
Thereafter, it is cooled, washed, dried, and fired at a temperature of 400 to 600°C to obtain crystalline borosilicate powder. If this powder is then treated with, for example, an aqueous ammonium nitrate solution, ammonium-type crystalline borosilicate can be obtained. In preparing the catalyst of the present invention, crystalline borosilicate may be applied in the form of a powder as it is, but it may also be applied as a molded body of a predetermined shape by adding an appropriate amount of alumina sol as a binder to the crystalline borosilicate. You can also do it. The phosphorus compounds supported on the crystalline borosilicate carrier include phosphoric acid, ammonium phosphate, sodium phosphate, potassium phosphate; alkyl phosphate esters such as methyl phosphate, ethyl phosphate, and butyl phosphate; Phosphorus oxychloride, phosphorus trichloride, phosphorus pentachloride; alkyl phosphites such as methyl phosphite and ethyl phosphite; metaphosphoric acid; pyrophosphoric acid; polycondensed phosphoric acid; aluminum hydrogen phosphate, sodium hydrogen phosphate, Examples include hydrogen phosphates such as potassium hydrogen phosphate and ammonium hydrogen phosphate. The supported amount of the phosphorus compound is 0.1 to 40 parts by weight, preferably 1 to 20 parts by weight, in terms of phosphorus pentoxide (P ₂ O ₅ ), based on 100 parts by weight of crystalline borosilicate.
Most preferably it is 2 to 10 parts by weight. If the supported amount is less than 0.1 parts by weight, the catalytic activity of crystalline borosilicate will not be sufficiently increased, and the selectivity in converting toluene to p-xylene will be low, and conversely if it exceeds 40 parts by weight, Undesirable phenomena such as phosphoric acid groups supported on crystalline borosilicate are eluted during molding using alumina sol and reduce binder strength occur. The phosphorus compound is supported by a method of mixing the above-described phosphorus compound and crystalline borosilicate in predetermined amounts, respectively;
After applying a method of impregnating a crystalline borosilicate powder or molded body with a predetermined amount of a solution of a phosphorus compound, or an ion exchange method when preparing modified zeolite,
This can be easily done by firing at a temperature of 500 to 1000°C. When a powder is used as the crystalline borosilicate, after supporting a phosphorus compound, if necessary, a binder such as alumina sol can be added and molded. The catalyst of the present invention enables the production of p-xylene from toluene and a methylating agent such as methyl alcohol;
Production of olefins from methyl alcohol, dimethyl ether, etc. in the presence of aromatic compounds such as benzene and toluene; Disproportionation of alkylbenzenes such as toluene; Isomerization of dialkylbenzenes such as mixed xylenes to p-dialkylbenzenes;
It can be used as a catalyst in a method for converting organic compounds such as, but it is particularly useful as a catalyst for increasing the selectivity in the production of p-xylene by the reaction of toluene and a methylating agent.
Here, the methylating agent includes methyl alcohol, dimethyl ether, methyl chloride, methyl bromide, etc., but methyl alcohol and dimethyl ether are particularly preferred. When producing p-xylene from toluene and methyl alcohol using the catalyst of the present invention, the reaction conditions may be selected appropriately, but the reaction temperature is usually 200-700°C, preferably 400-650°C, most preferably 400-650°C. Preferably 550 to 600°C, pressure is normal pressure to 100Kg/cm ² G,
Preferably normal pressure ~ 10Kg/cm ² G, most preferably normal pressure ~ 3Kg/cm ² G, weight hourly space velocity (WHSV) 0.1
-1000(hr) ^-1 , preferably 1-200(hr) ^-1 , most preferably 2-10(hr) ^-1 . In addition, the molar ratio of toluene and methyl alcohol used in the reaction is toluene/methyl alcohol = 20/1 to 1/10.
Preferably 10/1 to 1/2, most preferably 5/
It may be set to 1 to 1/1. Note that it is preferable to coexist hydrogen gas in the reaction atmosphere because the catalyst activity can be maintained for a longer period of time. Furthermore, when the catalyst of the present invention is further supported with at least one metal of group A of the periodic table, such as beryllium, magnesium, calcium, strontium, barium, and radium, in the form of an oxide, p-
The selectivity of xylene is increased, the carbonization phenomenon of organic compounds on the catalyst surface is suppressed, and the catalyst life is extended. The oxides of the metals mentioned above include inorganic salts of these metals such as nitrates, sulfates, and chlorides, specifically salts such as calcium sulfate and magnesium nitrate; calcium acetate, magnesium acetate, calcium formate, magnesium formate, etc. Organic acid salts; furthermore, hydroxides such as magnesium hydroxide and calcium hydroxide are mixed, impregnated, and supported by ion exchange in the same manner as the method applied to support phosphorus compounds, and then fired to a predetermined temperature. It can be generated by The supported amount of these metal oxides is based on 100 parts by weight of crystalline borosilicate.
It is preferably 0.1 to 20 parts by weight. As described above, the catalyst of the present invention is excellent as a catalyst for converting various organic compounds, especially for producing p-xylene from toluene, and can be applied to industrial fields such as oil refining and petrochemistry. Useful. The present invention will be explained in more detail below based on examples. Example 1 1 Preparation of comparative catalyst 1.34 g of boric acid, 17.68 g of concentrated sulfuric acid, and 26.32 g of tetrapropylammonium bromide were added to 250 ml of water.
Solution A added to water glass (composition: 28.95% by weight of silicon dioxide, 9.40% by weight of sodium oxide,
Solution B was prepared by adding 211.1 g of water (61.65% by weight) to 250 ml of water. Next, solution A and solution B were simultaneously added dropwise to a solution of 79.0 g of sodium chloride dissolved in 122 ml of water at room temperature over a period of 10 minutes. The resulting mixed solution was adjusted to pH 9.5 using sulfuric acid. Furthermore, this solution was placed in an autoclave and the reaction temperature was 170℃ for 20 minutes.
Heat treated for hours. After cooling, the contents of the autoclave were filtered and the resulting solids were washed.
It was dried at 120°C for 6 hours. By further baking at 550° C. for 8 hours, 50 g of crystalline sodium borosilicate was obtained. Next, 30 g of this crystalline sodium borosilicate was added to 5 times the weight of a 1N aqueous ammonium nitrate solution and refluxed for 8 hours. Thereafter, it was cooled and left to stand, and the supernatant liquid was removed by decantation. After repeating the reflux and decantation operations three times, the contents were filtered, washed, and dried at 120° C. for 10 hours to obtain 29.5 g of ammonium-type borosilicate powder. Alumina sol was added as a binder to the powdered ammonium borosilicate thus obtained so that the alumina content after firing was 20% by weight, and the mixture was molded, dried at 120°C for 4 hours, and then heated to 550°C.
It was baked for 6 hours. The composition of the obtained crystalline borosilicate was SiO ₂ /B ₂ O ₃ =50 (weight ratio). This borosilicate was designated as catalyst A. 2 Preparation of Example Catalyst Catalyst B 10 g of the ammonium-type crystalline borosilicate powder used in the preparation of the comparative example catalyst was added to a solution of 2.66 g of 85% phosphoric acid dissolved in 50 c.c. of water.
It was kept at 90°C for 16 hours and then evaporated to dryness. The obtained powder was dried at 120℃ for 16 hours and then dried at 550℃ for 6 hours.
Baked for an hour. Alumina sol was added as a binder to this fired powder so that the alumina content after firing was 20% by weight, and it was molded at 120°C.
After drying for an hour, it was fired at 550°C for 6 hours. The obtained fired body was designated as catalyst B. Catalyst C The ammonium type crystalline borosilicate powder used in the preparation of the comparative example catalyst was calcined at 550°C for 6 hours to obtain proton type crystalline borosilicate powder. 15 g of this powder was placed in a three-necked flask, heat-treated at 200° C. for 4 hours in an argon gas atmosphere, and then cooled to room temperature. Next, 100 g of phosphorous acid trimethyl ester was placed in the flask and heated at 112°C for 20 hours under an argon gas atmosphere.
The mixture was heated to reflux. After cooling, the contents were filtered, washed with dichloromethane and n-pentane, dried at 120°C for 6 hours, and then calcined at 550°C for 6 hours. Alumina sol was added as a binder to the obtained fired powder so that the alumina content after firing was 20% by weight, and it was molded, dried at 120°C for 6 hours, then fired at 550°C for 6 hours, and further fired at 900°C for 2 hours. did. The obtained fired body was designated as catalyst C. Catalyst D: Add 2.5 g of catalyst C to a solution of 0.51 g of magnesium nitrate dissolved in 50 c.c. of water, and heat at 90°C for 25 minutes.
After holding for an hour, it was filtered and washed. This was then dried at 120°C for 8 hours and then fired at 550°C for 6 hours. The obtained fired body was designated as catalyst D. Catalyst E 2.3 g of Catalyst C was added to a solution prepared by dissolving 0.47 g of calcium nitrate in 20 c.c. of water, held at 90° C. for 24 hours, and washed by filtration. This was then dried at 120°C for 8 hours and then fired at 550°C for 6 hours. The obtained fired body was designated as Catalyst E. 3. Production of p-xylene 2g of each of the above five types of catalysts were packed into an ordinary pressure fixed bed flow reaction tube, the reaction temperature was maintained at 600℃, and the weight hourly space velocity (WHSV) was 9.2 (hr) ^-1.
Then, toluene and methyl alcohol were introduced at a ratio of 4:1 (molar ratio), and the reaction was carried out for a predetermined time. The results are summarized in the table.

[Table] As is clear from the results in the table, it was found that the use of the catalyst of the present invention significantly increases the selectivity of p-xylene.

Claims (1)

[Scope of Claims] 1. A catalyst for converting organic compounds, comprising a phosphorus compound supported on crystalline borosilicate. 2 The supported amount of the phosphorus compound is the crystalline borosilicate
The catalyst according to claim 1, wherein the amount is 0.1 to 40 parts by weight per 100 parts by weight. 3. A method for converting an organic compound, which comprises bringing the organic compound into contact with a catalyst comprising a phosphorus compound supported on crystalline borosilicate under conversion conditions. 4. The method according to claim 3, wherein the conversion reaction is a reaction of reacting toluene with methyl alcohol or dimethyl ether to produce p-xylene. 5 1-20 moles of toluene and 10-20 moles of methyl alcohol
1 mole at a temperature of 200 to 700℃ and a pressure of normal pressure to 100℃.
0.1 to 100 parts by weight of crystalline borosilicate under conversion conditions of Kg/cm ² G, weight hourly space velocity of 0.1 to 1000 (hr) ^-1
5. The method according to claim 4, which comprises contacting a phosphorus-supported catalyst comprising 20 parts by weight of a phosphorus compound.