The method of hydrogenation of unsaturated cyclic compounds

 

(57) Abstract:

The invention relates to an improved method of hydrogenation of unsaturated cyclic compounds such as benzene and aniline, or cyclohexylaniline and dicyclohexylamine, obtaining, for example, cyclohexylaniline or cyclohexane. The method is carried out in the liquid phase in the presence of a hydrogenation catalyst in the shape of the distillation bridge, having a structure suitable for distillation, and which is a metal supported on a carrier of alumina in the reaction-rectifying column. The method includes the following stages: a)feeding to the column a first stream containing cyclic or polycyclic compounds, and a second stream containing hydrogen; b) introducing the contact unsaturated cyclic compounds and hydrogen at 37-190oC, partial pressure of hydrogen of less than 7,031 kg/cm2(less than 345 kPa), preferably less than 4,922 kg/cm2and the excessive pressure in the upper part of the distillation column from 1,0547 kg/cm2to 8,437 kg/cm2(from 101 to 929 kPa) in the presence of the above catalyst layer, with a part of unsaturated cyclic compounds reacts with part of the hydrogen with the formation of react is undergoing cyclic compounds; C) maintaining the pressure in the reaction-distillation column (I) so that the column was present in the vapor phase and a certain amount of the liquid phase and ensure continuous irrigation, whereupon the reaction mixture is boiling, which occurs in the catalyst bed, and (II) for condensing part of the vapors in the reaction system, resulting in the fraction of aromatic and other unsaturated cyclic and polycyclic compounds condensed on the catalytic structure; g) removing gateopener unsaturated cyclic compounds, gateopener saturated cyclic compounds and hydrogen in the form of the top ring of the reactive distillation column; d) the condensation of substantially all unsaturated cyclic compounds and saturated cyclic compounds removed as the top product from the reaction-rectifying columns; (e) the return part of the condensed unsaturated cyclic compounds and saturated cyclic compounds in the reaction-rectifying the column in the form of phlegmy; (e) removing from the reaction-rectifying column of liquid product containing saturated cyclic compounds and unreacted unsaturated cyclic is worn to the hydrogenation of unsaturated cyclic and polycyclic compounds. More specifically, the invention relates to a method, in which the hydrogenation of unsaturated cyclic and polycyclic compounds, and separating the product by distillation carried out simultaneously in the reactor-distillation column. More specifically, the method relates to the hydrogenation of benzene to obtain cyclohexane and to a method for cyclohexylamine by hydrogenation of aniline.

Prior art

Cyclohexane is the main raw material for producing products of nylon, and a great need for it remains. Cyclohexane was initially received a direct fractional distillation of suitable streams from refineries processing crude oil. Currently the main part of the cyclohexane get direct hydrogenation of benzene.

In U.S. patent 2, 373, 501 Peterson (Peterson) describes a liquid-phase method of hydrogenation of benzene to cyclohexane, in which there is a temperature difference between the top layer of the catalyst, which serves benzene, and output, where selected essentially pure cyclohexane. The temperature difference caused by the change of the exotherm of the liberated heat of reaction, as fewer and fewer benzene exposed Pribram Aksana. Inside the reactor is placed a coil for temperature control, in order to maintain the temperature difference, if the exothermic heat of reaction is insufficient, or in order to cool the layer, if you produce too much heat. Peterson acknowledges that while a lot of reaction occurs in the liquid phase, a portion of the benzene and cyclohexane is evaporated, especially near the top of the reactor where the concentration of benzene maximum conversion and higher. In order to condense able to condense the material and return it to the reactor, there is a reverse refrigerator. Thus, a substantial portion of the heat of reaction is removed by condensation reagents, evaporated during the entire reaction.

In U.S. patent 5, 189, 233 Larkin (Larkin) and others describe other liquid-phase method of hydrogenation of benzene to cyclohexane. However, Larkin and others use high pressure (175,8 kg/cm2, wt. 2500 pounds per square inch, wt.) in order to maintain the reactants in the liquid state. In addition, Larkin and others, describes the use of the catalyst with increasing activity as the concentration of benzene is reduced, in order to regulate the temperature and unwanted side reacts the n special catalyst. Reported catalyst is a Nickel deposited on a mixture of titanium dioxide and zirconium dioxide.

Hydrogenation of benzene is also useful to remove an aromatic compound of the threads of gasoline. One example of this method described Hsi (Hsieh and others in the U.S. patent 5, 210, 348, where the hydrogenation of the benzene fraction is used by itself or in combination with alkylation. In some schemes the recovery of aromatic compounds in gasoline the final boiling point 90% of the distillate AS TM D -86 set such that the aromatic and unsaturated cyclic and polycyclic compounds are removed from the tank for additives additives to gasoline. This is called intermediate gasoline T-90, which has the desired final boiling point 90% distillation according to ASTM. The obtained residual T-90+, which are largely unsaturated cyclic and polycyclic compounds must be eliminated, and an attractive alternative is their hydrogenation to obtain a lighter and more saturated compounds of the tank with gasoline.

A typical problem in the hydrogenation of benzene to cyclohexane are adverse reactions. In particular, neelathamara ring, leading to unwanted C5and more light products.

In the past, cyclohexylamine were obtained using several methods, including amination of cyclohexanol and hydrogenation of aniline. The main difficulty encountered in the hydrogenation of aniline is education changing the number byproduct of dicyclohexylamine.

It is known that catalysts promoting the hydrogenation of aniline are metals of group VIII of the periodic table. Previously, the tendency to form dicyclohexylamine was evaluated in a series of ruthenium < rhodium < PD = platinum, from least likely to most likely. Used substrates for metals are carbon, barium carbonate, alumina, barium sulfate and calcium carbonate. The substrate also affect the formation of dicyclohexylamine in the sequence charcoal>barium carbonate > alumina > barium sulphate > calcium carbonate.

Summary of the invention

The present invention includes a hydrocarbon feed stream containing aromatic and other unsaturated cyclic and polycyclic compounds, particularly benzene, together with a stream of hydrogen at ensuring the 10,55 kg/cm2, wt. (150 pounds per square inch, gage. ), preferably less than 7,031 kg/cm2, wt. (100 lbs/square inch, wt.), for example, less 4,922 kg/cm2abs. (70 lbs/sq. inch, abs.), more preferably less than 3,516 kg/cm2, abs. (50 pounds/square inch, abs.), in the interval from 0,141 kg/cm2, abs. (2 pound per square inch, abs.) to 1,758 kg/cm2abs. (25 lb/square inch, abs. ), in the reactor-distillation column containing a hydrogenation catalyst, which is a component framework for distillation and hydrasuit part of aromatic and other unsaturated cyclic and polycyclic compounds.

In the present invention in the hydrogenation of aniline is distilled from the catalyst, in order to gain an advantage due to the condensation of the distillate within the reaction zone by distillation reactor-distillation column. Real separation can only be viewed again. The reactor distillation column leads both to liquid and to vapour phase within the reaction zone by distillation. A significant part of the vapor is hydrogen and ammonia, although the part is aniline vapor. Within the reaction zone by distillation there is an inner irrigation and fluid from the external irrigation, which a cooling gap is hedgehogs

Fig.1 is a block diagram of one variant of the invention with the hydrogenation of benzene.

Fig. 2 is a block diagram of one variant of the present invention by hydrogenation of aniline.

Detailed description of the invention

In order to provide control of the desired temperature and residence time, it is proposed a method and apparatus in which the reaction liquid is boiling inside the reactor distillation column. The top straps are removed and condensed, and a portion of the condensate returned to the reactor-distillation column in the form of phlegmy. The advantage of this method is that due to continuous irrigation part of aromatics and other unsaturated cyclic and polycyclic compounds always condenses on the structure of the catalyst.

Without limiting the scope of the invention it is assumed that the mechanism behind the effectiveness of this method is the condensation of part of the vapors in the reaction system, when the condensed liquid is absorbed sufficient hydrogen to achieve the desired close contact between hydrogen and benzene in the presence of a catalyst that privode of the heat of reaction. As the fluid in the reactor is at the boiling point by applying pressure to regulate the temperature. Increasing the pressure increases the temperature and reducing the pressure reduces the temperature.

Used herein, the terms "cyclic" and "polycyclic" compounds include organic compounds with 2-50 carbon atoms, and oxygen, nitrogen, sulfur, and combinations thereof.

A preferred class has the structure of formula:

< / BR>
where each R is independently selected from hydrogen, alkyl, alkenyl, alkylaryl, NH2saturated and unsaturated cyclic structures formed by two R containing C, O, N, S or combinations thereof.

Some specific compounds include benzene, toluene, xylene, ethylbenzene, diethylbenzene, cumene, diisopropylbenzene, phenol, durene, pentamethylbenzene, naphthalene, 1,2,3,4-tetrahydronaphthalene, 1-methylnaphthalene, difenilmetana, 2,2', 3,3', 4,4', 5,5', 6-monomethylethanolamine, hexamethylbenzene, 1,2,4,5,6,8-hexamethyltetraline, pentamethylene, duranol, mesitol, methyldiphenylamine, pentamethylene, 1,1-dinaphthyl, 1,2,3,4-tetrahydronaphthalen (tetralin), 4,4'-dimethyl-1,1'-dinaphthyl, triphenylmethyl, p-dibenzoylbenzene, tetramethyldisilane, furan, thiophene, pyrrole, isopera, triazine, 1,3,2-oxazin, 1,2,5-oxathiazine, azepin, inden, benzofuran, indole, benzoxazole, coumarin, hinayaan, phenanthrene, benzonate, fluoran, xanthene, acridine, fixed, terpenes and naphthenes.

These hydrogenations can be carried out in order to get fully saturated compounds corresponding to the source material, or, in some cases, compounds with low unsaturation in relation to the original material. Often hydrogenation leads to rupture of the ring structure and to some cracking.

This hydrogenation processes are exothermic reactions. In the past the temperature was regulated by rapid cooling to important locations within the reactor by adding cold hydrogen. The addition of hydrogen also acted to maintain a molar excess of hydrogen inside the reactor, to prevent coking and other undesirable side reactions. We believe that in this reaction distillation with catalyst advantageous, first, because the reaction proceeds prototechno by distillation, and the initial reaction products and other flow components are removed from the reaction zone as quickly as possible, which reduces the probability of Bobov system, because all of the components boil. Heat of reaction just creates more boiling, and raise the temperature at a given pressure.

According to the present invention the method is carried out in full catalyst column, which, as you can see, contains a vapor phase and a certain amount of the liquid phase, as in any distillation. Reactor-distillation column operates at such pressure that the reaction mixture boils in the catalyst bed. This method of hydrogenation of benzene is carried out at a pressure in the upper part of the reactor-distillation column in the interval from 0 to 24,61 kg/cm2wt. (350 psi wt.), preferably 17,58 kg/cm2wt. (250 lbs/sq. inch. wt.), or less are eligible from 2,461 kg/cm2wt. (35 psi wt.) to 8,437 kg/cm2wt. (120 psi wt.), and when the temperature in the bottom zone of the specified reaction with distillation in the range of from 37,78o(100oF) to 260,0o(500oF), preferably from 65,56o(150oF) to 204,44o(400oF), for example from 100,00o(212oF) to 190,0o(374oF) when the required partial pressures of hydrogen.

When applying aniline as the raw materials of the present method is carried out under pressure to the NT/square inch. wt.), preferably 14,06 kg/cm2wt. (200 psi wt.), more preferably from 1,0547 kg/cm2or most preferably from 2,461 kg/cm2wt. (35 psi wt.) to 8,437 kg/cm2wt. (120 psi wt.), and when the temperature in the bottom zone of the specified reaction with distillation in the range of from 65,56o(150oF) to 260,00o(500oF), preferably from 121,11o(250oF) to 232,22o(450oF), for example from 148,89o(300oF) to 204,44o(400oF) when the required partial pressures of hydrogen.

Average hourly feed rate (JCSS), by which we mean the number of units of weight of raw materials coming in an hour in a distillation column reactor, the number of units of weight of catalyst structures for distillation from the catalyst may vary within a very wide range in the number of other parameters, for example from 0.1 to 35. The hydrogenation conditions used for other unsaturated cyclic and polycyclic compounds, such as benzene, although some connections may require a higher temperature to vaporize the materials used in the process.

In this way the temperature of the reg is of the reaction mixture. Thus the exothermic heat of reaction is dissipated by the latent heat of vaporization of the mixture. The evaporated portion is taken as the upper straps, and is able to condense the material to condense and return to the column in the form of phlegmy.

The current down the liquid causes more condensation inside the reactor, which is normal in any distillation. Contact condensable fluid inside the column provides excellent mass transfer for dissolution of hydrogen within the reaction fluid and simultaneous transfer of the reaction mixture to catalytic centers. It seems that the condensing mode of operation leads to excellent conversion and selectivity of the present process, and gives the opportunity to work at lower partial pressures of hydrogen and the temperature of the reactor than those noted. An additional advantage that can be obtained for this reaction from distillation from the catalyst, is the rinsing effect of the catalyst provided by the internal irrigation, through which decreases the formation of polymers and coking. Internal irrigation may vary in the range from 0.2 to 20 L/D (the weight of the liquid immediately below the words is, at least stoichiometric amounts. The preferred ratio exceeds the molar ratio of hydrogen to unsaturated cyclic compound, for example aniline equal to 4:1. You can submit ammonia in order to suppress side reactions and promote getting cyclohexylamine. The molar ratio of ammonia to aniline is preferably at least 1:1. Hydrogen should be present in an amount such that the molar ratio of hydrogen to ammonia was about 4:1.

Thus, you can put that method in the case of aniline includes:

a) feeding a first stream containing aniline, and a second stream containing hydrogen, the reactor-distillation column;

b) contacting aniline and hydrogen at a partial pressure of hydrogen in the range of from about 0,0070 kg/cm2wt. (0.1 pound per square inch, wt.) to less 10,55 kg/cm2wt. (150 pounds per square inch, wt.), preferably less than 7,031 kg/cm2(100 lbs/square inch, wt.), in the presence of a hydrogenation catalyst obtained in the form of patterns for distillation with a catalyst, whereby a portion of the aniline reacts with part of the hydrogen with the formation of a reaction mixture containing cyclohexylamine, nepareiziem is Alenia, that reaction mixture is at its boiling point;

g) removing gaseous aniline, gaseous cyclohexylamine and hydrogen in the form of the upper straps of the reactor-distillation column;

d) condensation of essentially all of aniline and cyclohexylamine removed in the form of the upper straps of the reactor-distillation column;

(e) the return part of the condensed aniline and cyclohexylamine in the reactor-distillation column in the form of phlegmy and

g) removing from the distillation column downstream of the liquid product containing cyclohexylamine.

The catalyst was prepared in the form of patterns for distillation from the catalyst. More specifically, the hydrogenation catalyst is usually a metal supported on a carrier of alumina, in the form of extrudates or spheres. The extrudates or spheres are placed in a porous container and suitably supported in the reactor-distillation column, to allow vapor flow through the layer, while providing sufficient surface area for catalytic contact.

Among the metals, known as catalysts for hydrogenation reactions include platinum, rhenium, cobalt, molybdenum, Nickel, tungsten and palladium is nalivajut in active form or a reducing agent before use, any hydrogen in the source material during the application. At elevated temperatures these metals also catalyze other reactions, most notably the dehydrogenation. In addition, with the increase in time they can promote the reaction of olefinic compounds with each other or with other olefins, with the formation of dimers or oligomers.

One of the preferred options relates to the production of cyclohexane by hydrogenation of benzene. When the product is cyclohexane containing benzene feedstock is characterized in that it preferably contains at least 5 weight. % benzene to 100 wt.%. Other components are usually5C6and C7-hydrocarbons. So how can gidrirovaniya and other unsaturated compounds, their presence is harmful to the method, when the desired product is cyclohexane. Preferably, other unsaturated compounds were limited to at least 30% of the raw materials. The preferred diluent is cyclohexane, as it is the required product. However, valid other inert substances, such as other alkanes, for example WITH5-C9-alkanes.

The molar ratio of hydrogen to>As described, used in the process of hydrogenation catalytic material is in a form that serves as a distillation bridge. In a broad sense, the catalytic material is a component of a distillation system and functions as a catalyst and as a distillation bridge, i.e. the attachment of a distillation column is used for distillation, and as a catalyst.

The reaction system can be described as heterogeneous as the catalyst remains an excellent subject. You can use any suitable hydrogenation catalyst, for example with metals of group VIII of the Periodic table of elements as a main catalytic component, by itself or with activators and modifiers, for example, palladium/gold, palladium/silver, cobalt/zirconium, Nickel, preferably deposited on a substrate, such as alumina, refractory brick, pumice, coal, silica, resin, etc.

The preferred structure of the catalytic hydrogenation of benzene contains at least one set of flexible, semi-rigid tubular elements with open cells, and these elements are filled with a catalytic material in the form of particles (component-kata is supported by this sieve, and these tubular elements are arranged in rows at an angle to the longitudinal axis, thus forming a beam, and is described in detail in U.S. patent 5, 431, 890, included in the description of the invention.

Flexible, semi-rigid tubular member with open cells, filled with a catalytic material in the form of particles, preferably has fastening means every 2,54-30.48 cm (1 to 12 inches) along the length of the tube with the formation of patterns for distillation with a catalyst, which given the shape with numerous connections. Connection formed by the fixing means can be arranged uniformly or irregularly.

Structure for distillation with a catalyst in the form of a beam formed by placing at least one tubular element on top of the wire sieve, such as a grid of drop entrainment, in a diagonal manner so that when the wire mesh roll, folded structure leads to a new and improved structure for distillation from the catalyst. Additional options include mnohopocetny build a temporary wire sieves and tubular elements, which roll in a new structure for distillation with a catalyst in the form of a beam. Tubular elements on peremezhaya peresekayutsya. Each tubular element to define a spiral inside the beam.

Component, the catalyst may be in several forms. In the case of catalytic material in the form of particles, powder (particle size) is usually from 60 mm to about 1 mm enclosed in a porous container, such as wire mesh or plastic mesh. Used for the manufacture of the container material must be inert to the reagents and the conditions in the reaction system. Wire mesh can be made from aluminum, steel, stainless steel, etc., Polymeric mesh may be nylon, Teflon, etc., the Number of sieves or the number of threads per 2.54 cm (inch) material used for the manufacture of the container is such that the catalyst was kept in it do not pass through holes in the material. Although you can use the catalyst particles size of about 0.15 mm or powders in containers you can use particles with a diameter up to about 0,635 cm (1/4 inch).

In Fig.1 depicts a block diagram of a variant of the invention for benzene. Benzene is served by lines 1 and hydrogen - line 2, and both of them connect in line 3, from which hydrogen and benzene do the following structure for distillation with catalyst 12 contained in the reactor-distillation to what I started and balancing process, provide circulation flow VAT residue 4 through the reboiler 50 and the return line 5. Benzene boils down to the catalyst layer, where it is partially reacts with hydrogen with formation of a reaction mixture containing cyclohexane as the reaction product, unreacted benzene and unreacted hydrogen. Exothermic heat of reaction causes additional boiling of the reaction mixture and evaporated part exits the column as the top straps through the conveyor line 7. At the top shoulder straps also there is unreacted hydrogen. Gaseous top shoulder straps containing benzene, cyclohexane and hydrogen, is passed through the condenser 30 where it condenses essentially all of the benzene and cyclohexane. Then thread the top straps through the receiver/separator 40 where the separated gas, which is mostly hydrogen, and collect the liquid. Through the line 9, the gas is removed to return to repeat the cycle, or it is used later in the process.

Part of the condensed fluid returns in the form of phlegmy in a distillation column, where it provides additional cooling and condensation inside the column. VAT residue containing benzene and cyclohexane, removing the of abovich products not selected. The flow downstream of the liquid product in the end is passed through the conveyor line 6 in odnotsiklovoy reactor with a porous layer 20 containing a fixed bed of hydrogenation catalyst 14, where essentially all unreacted benzene hereroense in cyclohexane. In the second reactor 20 via flow line 13 serves hydrogen, which can conveniently be selected from the outlet opening 9 of the upper receiver of a shoulder strap 40, if required. This method allows the use of much lower partial pressure of hydrogen and a slightly lower temperature than in conventional ways.

In Fig.2 shows a block diagram of one variant of the invention. Aniline is available on line 101 in the reactor-distillation column 110 in place over the catalyst layer 112 containing structure for distillation from the catalyst. Via flow line 102 serves hydrogen, and via flow line 103 serves ammonia, which are connected in a flow line 104 and serves lower layer 112. The upper shoulder straps containing cyclohexylamine and unreacted aniline and hydrogen are selected via flow line 105 and passed through the reflux condenser 120, where it is condensed able to condense the material. After that, the upper straps are collected in receiver/separator is on the production line 111 for recycling (not shown) in the feed hydrogen or place under a layer of catalyst. The product is taken on the production line 115 and a portion of the condensed top straps return to the reactor-distillation column 110 in the form of phlegmy on production line 113.

Distillation residues are taken via flow line 106 and a portion is passed through the reboiler 140 to balance the heat to the column 110. Distillation residues containing heavy by-products, including cyclohexylaniline and dicyclohexylamine. Part of the VAT residue can be recycled to the original material on the production line 107 to become cyclohexylamin. In order to prevent the formation of high-boiling substances, a drainage VAT residue on the production line 108.

Reactor-distillation column fitted with a distillation section 114 for separating unreacted aniline from the product and evaporating section 116 to ensure that no amount of aniline or product was not removed in the form of VAT residue.

In examples 1-3 was used reactor-distillation column with a diameter of 2.54 cm (1 inch). The above-described structure of the catalyst was placed in the upper part of the reactor length 3,962 m (13 ft). The bottom part of the length of 2,134 m (7 feet) filled with inert distillation packing. Individually reached the required temperature difference between the top and bottom, set the flow rate and included a stream of hydrogen. Once at the top of the receiver was observed level, the flow of cyclohexane is stopped and the device is operated at full irrigation for two hours before he started feeding benzene/cyclohexane. In order to balance the column was installed drainage products - liquid substances the top of a shoulder strap.

Example 1

400 g of Nickel catalyst supported on alumina in the form of spheres of the size of 1.5875 mm (1/16 inch) (54 wt.% Ni), loaded in the tubular elements turned into the beam, as previously described, and placed in the reactor-distillation column. Conditions and results are given in table. I.

Example 2

280 g of a platinum/palladium catalyst supported on alumina (0.3 weight. % Pt, 0.5 wt.% Pd), was loaded into the tubular elements turned into the beam, as previously described, and placed in the reactor-distillation column. Conditions and results are given in table. II.

Example 3

400 g of tablets with Nickel supported on alumina size 0.2931 mm (3/26 inch) (54 wt.% Ni), loaded in the tubular elements turned into the beam, as previously described, and placed in the reactor-distillation column. Conditions and results are given in table. III.

Predpochetaet and also the hydrogenation of any thread containing cyclic and polycyclic unsaturated compounds, for example the residue of gasoline T-90+. Such unsaturated compounds include aromatic compounds, polynuclear aromatic compounds and cyclic alkenes, such as naphthenes.

In the following examples used the reactor-distillation column height of 7.62 m (twenty-five feet) and a diameter of 2.54 cm (one inch). The catalyst is Calsicat E-475 SR, 56% Nickel on alumina in the form of spheres of size 4.7623 mm (3/16 inch). The catalyst was Packed in the above-described "sausages" length of 15.24 cm (six inches) and a diameter of 1.905 cm (0.75 inches), folded with a stainless steel sieve with openings 100 mesh.

Example 4

In this example, 0.2994 kg (0.66 lb) Calsicat E-475, obtained as described above was loaded in the middle part of the length of 3.048 m (10 ft) reactor-distillation column. The top and bottom of the length 2.286 m (7,5 feet) were filled ceramic saddle-shaped nozzles. Conditions and results are summarized in table. IV. The data indicate that the pressure (and thus temperature in the zone of catalyst) had the biggest influence on performance, which ranged from -0.15 kg/kg of catalyst (lb/lb kata the square inch, wt.). Selectivity for cyclohexylamino was in the range of 65-75%, and the main by-products were cyclohexylaniline and dicyclohexylamine.

Example 5

In this example 0.454 kg (1.0 lb) Calsicat E-475, obtained as described above was loaded in the lower part of the length 4.572 m (15 ft) reactor-distillation column. The top part of the length of 3.048 m (10 ft) Nabil ceramic saddle-shaped nozzle. Conditions and results are given in table. V. During part of the experience (from approximately 250 hours or more), the product of heavy VAT residue containing cyclohexylaniline and dicyclohexylamine returned to repeat the cycle with a flow rate equal to 20% of the fresh raw material.

1. The method of hydrogenation of unsaturated cyclic compounds in the liquid phase in the presence of a hydrogenation catalyst, wherein the hydrogenation is carried out in the reaction-distillation column, including the following stages: a) feeding to the column a first stream containing unsaturated cyclic or polycyclic compound and a second stream containing hydrogen; b) introducing the contact unsaturated cyclic compounds and hydrogen at a temperature of from 37 to 190oC, partial pressure of hydrogen of less than 7,031 kg/cm2(mininni columns from 1,0547 kg/cm2to 8,437 kg/cm2(from 101 to 929 kPa) in the presence of a layer of a hydrogenation catalyst in the shape of the distillation bridge, having a structure suitable for distillation, and represents a metal supported on a carrier of alumina, with some unsaturated cyclic compounds reacts with part of the hydrogen with the formation of a reaction mixture containing saturated cyclic compounds, unreacted hydrogen and unreacted cyclic compounds; C) maintaining the pressure in the reaction-distillation column (1) such that the column was present in the vapor phase and a certain amount of the liquid phase and ensure continuous irrigation, resulting reaction mixture is boiling, which occurs in the catalyst layer (11) and for condensing part of the vapors in the reaction system, resulting in the fraction of aromatic and other unsaturated cyclic and polycyclic compounds condense on the catalytic structure; g) removing gaseous unsaturated cyclic compounds, gaseous saturated cyclic compounds and hydrogen in the form of the top ring of the reactive distillation column; d) condensation, by creatures who's fire from the reactive distillation column; (e) the return part of the condensed unsaturated cyclic compounds and saturated cyclic compounds in the reactive distillation column in the form of phlegmy; g) removing from the reaction-distillation column of liquid product containing saturated cyclic compounds and unreacted unsaturated cyclic compounds of the condensed top straps.

2. The method according to p. 1, characterized in that the excess pressure in the upper part of the reactive distillation column is to 24,61 kg/cm2.

3. The method according to p. 1, characterized in that the excess pressure in the upper part of the reactive distillation column is from 2,461 to 8,437 kg/cm2.

4. The method according to p. 1, characterized in that the partial pressure of hydrogen is from 0,0070 to 3,516 kg/cm2.

5. The method according to p. 3, characterized in that the partial pressure of hydrogen is from 0,141 to 1,758 kg/cm2.

6. The method according to p. 1, characterized in that the unsaturated cyclic compounds are used aniline with obtaining a saturated cyclic compound is a cyclic compound cyclohexylamine.

7. The method according to p. 6, characterized in that mo is together with the incoming hydrogen or in another location below the catalyst bed.

8. The method according to p. 6, characterized in that the reaction mixture as byproducts cyclohexylaniline and dicyclohexylamine.

9. The method according to p. 6, characterized in that the reaction-distillation column serves ammonia in the form of the third stream.

10. The method according to p. 8, characterized in that cyclohexylaniline and dicyclohexylamine removed from the specified reactive distillation column in the form of VAT residue.

11. The method according to p. 8, in which the part of the said VAT residue recyclist as raw material in the reaction-distillation column together in aniline, to convert part of cyclohexylaniline and dicyclohexylamine in cyclohexylamin.

12. The method according to p. 6, characterized in that the excess pressure in the upper part of the column is to 24,61 kg/cm2.

13. The method according to p. 12, characterized in that the temperature inside the catalyst layer is in the range from 65,56 to 260,0oC.

14. The method according to p. 1, characterized in that the unsaturated cyclic compounds are used benzene, and the benzene and hydrogen is introduced into contact at a partial pressure of hydrogen of less than 4,922 kg/cm2obtaining as on the e pressure in the upper part of the reactive distillation column is to 24,61 kg/cm2.

16. The method according to p. 15, characterized in that the excess pressure in the upper part of the reactive distillation column is from 2,461 to 8,437 kg/cm2.

17. The method according to p. 14, wherein spend the additional step of hydrogenation of the head of liquid product containing cyclohexane and unreacted benzene, together with hydrogen in odnotsiklovoy the reactor with a fixed bed containing a hydrogenation catalyst, for degidrirovaniya essentially all unreacted benzene with hydrogen in order to obtain additional quantities of cyclohexane.

18. The method according to p. 16, characterized in that the temperature of the VAT residue in the distillation column is from 100,0 up 190,0oC.

19. The method according to p. 14, characterized in that during the hydrogenation of benzene submit benzene and hydrogen at a molar ratio of hydrogen to benzene from 1.5: 1 to 41: 1; support the excess pressure in the upper part of the reactive distillation column from 2,461 to 8,437 kg/cm2in such a way that the reaction mixture is at its boiling point and the partial pressure of hydrogen is from 0,141 to 1,758 kg/cm2abs. ; and conduct additional step gidrirovanny aciclovir reactor with fixed bed, containing the catalytic hydrogenation, dehydrogenation essentially all unreacted benzene with hydrogen in order to obtain additional quantities of cyclohexane.

20. The method according to p. 19, wherein the first stream is supplied to the hydrogenation of the raw material, includes an unsaturated cyclic or polycyclic compounds and contains 5-36 wt. % benzene.

Priority points:

06.03.1995 - PP. 1-8, 17-20;

14.03.1995 - PP. 9-16.

 

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FIELD: chemistry.

SUBSTANCE: invention describes a catalyst where atomic ratio of nickel to magnesium ranges from 5 to 75. Particularly, the invention concerns a catalyst including nickel, silicon dioxide, aluminum oxide and magnesium, with atomic ratio of nickel to silicon (Ni/Si) ranging from 2 to 30, atomic ratio of nickel to alumiunum (Ni/Al) ranging from 9 to 40, and atomic ratio of nickel to magnesium (Ni/Mg) ranging from 5 to 75. Additionally the invention concerns method of obtaining such catalyst and method of hydration of non-saturated fatty substance.

EFFECT: improved activity of the catalyst for oil hydration and streamlined technology of catalyst obtaining.

9 cl, 1 tbl, 8 ex

FIELD: chemistry.

SUBSTANCE: invention relates to production of catalysts and can be used in chemical industry and in production of medications. Described is method of preparing modified platinum catalyst for enantioselective hydration of esters of alfa-ketacarboxylic acids which includes impregnation of hexachloroplatinic acid from solution into pores of prepared carrier, as such supersewn polystyrene is used, by water-absorbing capacity from solution tetrahydrofurane : methanol : water with ratio 4:1:1, mixture of hexachlorplatinic acid and carrier is kept during 10-15 minutes mixed, after which it is dried at 70-75°C, washed with Na2CO3 solution with further reduction of hexachlorplatinic acid, filtering, washing and drying of catalyst and modification with cinchonidine solution.

EFFECT: reduction of time of catalyst preparation, increase of catalyst activity, enentioselectivity and stability.

4 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to selective heterogeneous nickel catalysts for hydrogenation of unsaturated hydrocarbons and sulphur removal and methods for production and use thereof. Described is a selective heterogeneous catalyst containing nickel on a support which is a diatomite powder having the following physical properties: BET surface area 20-50 m2/g, particle size less than 10 mcm - no more than 15 wt %, greater than 71 mcm - no more than 40 wt %, 10-71 mcm - the balance, or crushed shale taurite, having the following physical properties: BET surface area 12-16 m2/g, particle size less than 10 mcm - no more than 40 wt %, or a mixture thereof in ratio of 50:50. The catalyst has the following composition, wt %: nickel 52.0-54.0, aluminium oxide 2.5-3.8, iron oxide 1.3-1.7, sodium oxide 0.5-1.5, calcium oxide 0.1-0.6, magnesium oxide 0.25-0.8, sulphide sulphur 0.1-0.5, silicon dioxide - the balance. Also described is a method of producing said catalyst by mixing a support with 5-6% aqueous nickel sulphate solution, adding to the obtained suspension 25-27% calcined soda solution until achieving molar ratio of calcined soda to nickel sulphate of 1.6-1.7:1.0, at medium pH 9.0, or in two steps: at the first step to molar ratio calcined soda to nickel sulphate of 0.8-0.9:1.0, at medium pH 6.0-7.0, at the second step to molar ratio calcined soda to nickel sulphate of 1.6-1.7:1.0, at medium pH 9.0-10.0. Further, the method includes steps of filtering, washing, drying and pelletising without steps of reducing with hydrogen and passivation with a nitrogen-air mixture. Before use, activation of the fresh catalyst or recovery of the catalyst after 1500-3000 hours of contact thereof with the material is carried out directly in the hydrogenation reactor in a current of circulating hydrogen at 230-500°C for 5-50 hours. Also described is a method of using said catalyst.

EFFECT: achieving high activity, selectivity and stability of hydrogenating unsaturated hydrocarbons and sulphur removal.

6 cl, 6 tbl, 9 ex

FIELD: chemistry.

SUBSTANCE: invention refers to a catalyst element used in hydration processes. The presented catalyst element contains a noble metal, which represents palladium, and an element of lanthanide group. which represents europium coating a carrier containing a substantially nonporous glass-containing substrate. The above glass-containing substrate has a specific surface measured by S.A.N2-BET method based on N2 heat adsorption/desorption or S.A.Kr-BET method based on Kr heat adsorption/desorption, within the range of 0.01 m2/g to 10 m2/g, and a rate of specific surface change by sodium chemical absorption SACRNa≤0.5. Palladium and europium each present in an amount of 10 portions per million by weight to 1 % by weight, on account of the catalyst element weight. The invention also refers to a method for feed stream hydration in the presence of the above catalyst element and to a method for producing the above catalyst.

EFFECT: presented catalyst element possesses selective and stable activity in the hydration processes.

8 cl, 3 dwg, 5 ex

FIELD: chemistry.

SUBSTANCE: describes the non-activated Renei catalyst on the carrier. The catalyst comprises an organic polymeric carrier material and Renei alloy particles. The Renei alloy particles are supported on a polymeric carrier material, where substantially all the particles are partially embedded in the carrier material. In this case, the particles of the Renei alloy are distributed unevenly in the catalyst and the concentration of particles in the surface portion of this carrier is greater than the concentration of the particles of the Renei alloy in the middle part of this carrier. Activation of the catalyst is carried out by activating a non-activated supported catalyst with a caustic aqueous solution.

EFFECT: preparation of Renei catalyst with high activity, good selectivity and easy extraction of metal.

17 cl, 2 dwg, 3 tbl, 10 ex

FIELD: industrial organic synthesis.

SUBSTANCE: isopropyl alcohol production process comprises hydrogenation of starting acetone including from 0.01 to 10000 ppm benzene in presence of hydrogen and catalyst to give isopropyl alcohol and benzene hydrogenation products, acetone and benzene contained in feedstock being hydrogenated simultaneously. In its second embodiment, isopropyl alcohol production process comprises product separation stage. Process of producing phenol and isopropyl alcohol containing benzene hydrogenation products comprises stages: alkylation of benzene with isopropyl alcohol and/or propylene to form cumene, oxidation of resulting cumene into cumene hydroperoxide, acid cleavage of cumene hydroperoxide to produce phenol and acetone including from 0.01 to 10000 ppm benzene, preferably concentration of produced benzene-polluted acetone, and catalytic hydrogenation of benzene-polluted acetone into isopropyl alcohol containing benzene hydrogenation products, hydrogenation of benzene and acetone proceeding simultaneously.

EFFECT: enhanced process efficiency.

3 cl, 1 dwg, 1 tbl

FIELD: chemistry.

SUBSTANCE: invention concerns single-stage method of obtaining fructopiranose sulfamate derivatives of the general formula (I) , where X is selected out of CH2 or O; R3, R4, R5 and R6, each selected independently out of hydrogen or low-grade alkyl, then X is CH2, R5 and R6 can be alkene groups linked with formation of benzene ring, then X is O, R3 and R4 and/or R5 and R6 together can be methylenedioxy group of the formula: , where R7 and R8 are equal or different and denote hydrogen, low-grade alkyl, or are an alkyl and are linked together to form cyclopentyl or cyclohexyl ring; , involving reaction of compound of the formula (II) with sulfuryldiamide at high temperature in the presence of 0 to ca. 10% of water, resulting in obtaining of respective compound of the formula (I); and method of obtaining compound of the formula (1a).

EFFECT: development of a single-stage method for obtaining fructopiranose sulfamate derivatives.

29 cl, 10 tbl, 10 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a copper-modified nickel catalyst for hydrogenation of an aromatic compound to obtain a hydrogenated cyclic compound containing from 4 to 10 wt % Ni and from approximately 0.2 to 0.9 wt % Cu, deposited on a support made from transition aluminium oxide with BET specific surface area from approximately 40 to 180 m2/g and pore volume from approximately 0.3 to approximately 0.8 cm3/g, where the catalyst contains one or more modifying components selected from a group consisting of Ag and Ru. The invention also relates to a method of hydrogenating aromatic compounds in a reaction stream which uses the catalyst given above.

EFFECT: increased efficiency of the method of hydrogenating aromatic compounds.

19 cl, 6 tbl, 6 ex

FIELD: explosives.

SUBSTANCE: invention relates to method for hydrogenation of benzene in adiabatic reactor of shelf type by means of benzene contact with catalyst placed on shelves, at higher temperature and pressure in presence of hydrogen-containing gas supplied to reactor together with benzene in upper part, and also in space between layers of catalyst, characterised by the fact that 50-70 wt % are supplied to upper part of reactor, from initial benzene together with 40-70% of overall volume of hydrogen-containing gas, and remaining part of benzene and hydrogen-containing gas is evenly distributed and supplied together in space between layers of catalyst.

EFFECT: improved efficiency of process, increased volume speed of raw materials feed, production of cyclohexane of high extent of purity or high-octane component of commercial petrol with minimum content of benzene.

3 cl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to two versions of a method for synthesis of aromatic compounds, on of which involves: a methanation step involving contact between a hydrogen-containing gas and carbon monoxide and/or carbon dioxide in the presence of a catalyst which causes reaction of hydrogen contained in the gas with carbon monoxide and/or carbon dioxide and conversion of these components to methane and water; and a step for synthesis of an aromatic compound with reaction of lower hydrocarbon with methane obtained at the methanation step in the presence of a catalyst to obtain a gaseous reaction product containing aromatic compounds and hydrogen, where the aromatic compounds are separated from the gaseous reaction products obtained at the aromatic compound synthesis step, and the remaining hydrogen-containing gas is taken to the methanation step. The invention also relates to a method for synthesis of hydrogenated aromatic compounds obtained using methods described above.

EFFECT: possibility of obtaining aromatic compounds through catalytic reaction of lower hydrocarbons.

14 cl, 13 tbl, 3 ex, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to versions of a method of hydrogenating benzene, mixture of benzene and toluene, mixture of benzene and xylene or isomeric mixture of xylene or mixture of benzene, toluene and xylene or isomeric mixture of xylene containing sulphur aromatic compounds, in one of which at the first step, in the presence of hydrogen if necessary, content of sulphur aromatic compounds is reduced in the presence of a desulphonation agent containing copper and zinc in atomic ratio between 1:0.3 and 1:10 (step a), and at the second step benzene, mixture of benzene and toluene, mixture of benzene and xylene or isomeric mixture of xylene or mixture of benzene, toluene and xylene or isomeric mixture of xylene is hydrogenated in the presence of a ruthenium catalyst containing 0.01-30 wt % ruthenium in terms of total weight of the catalyst deposited on a support, in the presence of hydrogen (step b). The invention also relates to a desulphonation method using the same desulphonation agent.

EFFECT: use of present method enables to obtain alicyclic compounds or their mixture with high selectivity and output.

24 cl, 3 ex, 14 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing a compound of general formula (I), involving steps in accordance with the following scheme:

, where at separate steps: a) a compound of formula (IX) is converted to a compound of formula (V) in the presence of an enzyme selected from lipase B from Candida antarctica, b) the compound of formula (V), in the presence of an acid catalyst through effect of a compound which can form a protective group Z3 which is stable in alkaline medium and labile in acidic medium, is converted to a compound of formula (VIII) and c) the compound of formula (VIII) is converted to a compound of formula (II) in the presence of a nucleophilic agent; d) in the presence of a base B1, the compound of formula (II) is converted through effect of a compound of formula (VI) to a compound of formula (IIIa); e) the compound of formula (IIIa) is converted to a compound of formula (IVa), where the corresponding conversion is carried out through effect of an alcohol in the presence of an acid catalyst; f) through the effect of the compound (VII), the compound (IVa) is converted to a compound of formula (Ia) in the presence of a base B1 and g) if needed, the compound (Ia) is hydrolysed or hydrogenolysed to a compound of formula (I), if R3 denotes H; wherein the compound (IX) is a pure cis-isomer or a mixture of cis/trans-isomers, respectively; variables and substitutes assume the following values, respectively: ring A is C3-C8cycloalkyl, R1, R2, R4 and R5 independently denote , F, CI, Br, C1-C6alkyl or -O-(C1-C6alkyl); R3 denotes H, C1-C6alkyl; R6 denotes C1-C6alkyl or benzyl; X denotes C1-C6alkyl; Y denotes C1-C6alkyl; Z1 denotes a protective group which is stable in acidic medium; Z2 denotes a protective group which is stable in acidic medium; Z3 denotes a protective group which is stable in alkaline medium and labile in acidic medium; Z4 denotes a leaving group; Z5 denotes a leaving group; B1 denotes a tertiary alcoholate of an alkali-earth metal, a tertiary alcoholate of an alkali metal, an amide of an alkali-earth metal, an amide of an alkali metal, a silazide of an alkali-earth metal, a silazide of an alkali metal or a hydride of an alkali metal. The invention also relates to a method of producing a compound of general formula (I), involving steps in accordance with the following scheme:

, where at separate steps: a2) through at least one acyl group donor and in the presence of an enzyme selected from lipase B from Candida antarctica, the compound of formula (X) is converted to a compound of formula (V); steps b) - g) are described above, wherein the compound (X) is a pure cis-isomer or a mixture of cis/trans-isomers respectively. The invention also relates to a compound of general formula (IIIa), where ring A is cyclohexyl, where the X-containing and Z3-containing substitutes are in the cis-1,3-position of the cyclohexyl fragment; R1, R2 and R4 independently denote H, F, Cl, C1-C3alkyl or -C(O)-(C1-C6alkyl); Z3 denotes tetrahydropyranyl; X denotes methyl, and to a compound of general formula (VIII), where ring A is cyclohexyl, wherein the Z1-containing and Z3-containing substitutes are in the cis-1,3-position of the cyclohexyl fragment; Z1 denotes -C(O)CH3; Z3 denotes tetrahydropyranyl.

EFFECT: efficient method of obtaining the said compound.

14 cl, 5 dwg, 2 tbl, 27 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing cyclohexane from unsaturated hydrocarbons, characterised by that a mixture of acetylene and natural gas in ratio of 46-48:52-54 mol % undergoes mechanical activation at temperature 20°C for 3-10 minutes in the presence of crystalline quartz.

EFFECT: present method enables to obtain cyclohexane in a single step, without additional pressure and at low temperatures.

2 cl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of controlling water washing of oxidate in production of caprolactam, which is carried out in a fractionation column while feeding a reaction mixture, controlling temperature conditions using an external heat exchanger and removing the distillate and bottom product through condensers. The method is characterised by that it further includes a pump for feeding oxidate, which is connected to the first input of the oxidate heat exchanger, the second input of which is connected to a cyclohexane container; the first output of the oxidate heat exchanger is connected to the first input of a mixer, the second input is connected to a pump for feeding water-organic distillate into the container, and the first output is connected to the first input of the main separation vessel, the second output of which is connected through the mixer to the first input of an additional separation vessel, its second input is connected to a pump for feeding condensate from a collector having a flow sensor and a valve, and its first output is connected to a pump for feeding a water-acid layer into a pipe for feeding the water-organic distillate into the mixer and into a feeding pipe having a flow sensor and a valve from the mixer into the additional separation vessel having a level sensor and a valve, its second output is connected through the valve to a concentration pipe, and the third output is connected to an oxidate neutralisation pipe. The first output of the main separation vessel having a pressure sensor, a level sensor and a valve is connected through a filter to a heat exchanger for stripping organic matter, having a vapour flow sensor and a valve and with a fractionation column. There are also pipes for connecting a hydraulic gate with a distillate collector, which are connected to condensers, wherein the first output of the condensate collector is connected by a pipe to the top of the fractionation column having a vapour flow sensor and a valve, and the second and third outputs of the distillate collector feed the distillate through the pipes to the next processing steps.

EFFECT: use of the present invention improves control of separating cyclohexanol and cyclohexanone, and reduces caprolactam loss and alkali consumption.

4 cl, 1 tbl, 1 dwg

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