The way to obtain olefinic hydrocarbons

 

(57) Abstract:

Usage: petrochemistry. Paraffin hydrocarbons digitalout at a temperature of from 450 to 800oC, a pressure of from 0.1 to 3 ATM. abs. and flow rate of gas from 100 to 1000 h-1in the presence of a catalyst having the composition, wt. %: (preferred) Cr2O36,0 - 30,0 (13 - 25), Sn 0 0,1 - 3,5 (0,2 - 2,8), MeO 0,4 - 3,0 (0,5 - 2,5), SiO2of 0.08 to 3.0 (0,08 - 3,0), Al2O3else, where Me is an alkali metal, preferably potassium. The method allows to increase the yield of the target product. 8 C.p. f-crystals, 2 tab. 1 Il.

The invention relates to the field of production of olefinic hydrocarbons, in particular olefinic hydrocarbon, C2-C20, the dehydrogenation of paraffin hydrocarbons.

Olefins are important intermediate substances for the production of chemical products, with a wide distribution, such as polypropylene, high-octane additives (methyl-tertiary-butyl ether (MTBE), a fuel with a high octane number, alkylacrylate and many other products.

Despite the growing demand for these products, the expansion of their production is often impossible due to the limited availability of olefins, such as isobutylene for Mtber, cracking). Among them, the source, which is becoming more and more important is the reaction of dehydrogenation of light paraffin hydrocarbons. This reaction is simple from the point of view of stoichiometry, has problems in terms of thermodynamics and kinetics. The reaction is endothermic and is governed by thermodynamic equilibrium. This leads to the necessity of creating a temperature above 500oC for the dehydrogenation of C2-C20paraffins to produce economically profitable conversions per pass. In addition, there is a need to provide a system warmth.

Despite the high operating temperatures, the rate of dehydrogenation of low and therefore it is necessary to use an appropriate catalyst. The latter must be thermally stable and able to guarantee a high selectivity to the desired olefin while keeping to a minimum adverse reactions isomerization, cracking, coke formation and flavoring and provide suitable industrial value conversion.

The inevitable formation of coke on the catalyst causes the progressive loss of catalytic activity, and therefore it is necessary to conduct periodic regeneration.

And, as a result, the catalytic composition of the AI.

Known methods for producing olefinic hydrocarbons by dehydrogenation at elevated temperatures corresponding paraffin hydrocarbons in the presence of catalytic compositions based on noble metals (U.S. Patent N 3531543, 4786625, 4886928 and Europe. patent N 351067), and also on the basis of metal oxides in the presence of promoters, in most cases, this is caused Cr2O3(U.S. patent N 2945823, 2956030, 2991255 and the United Kingdom patent N 2162082).

However, both groups of these compounds have drawbacks. The formulations based on noble metals require special processing at the stage of regeneration with the aim of preserving dehydrating activity of metal components, for example post-processing chlorine-containing substances with subsequent restoration (U.S. Patent N 4438288). Structures on the basis of chromium oxide supported on alumina, silica, silica - alumina, etc. are characterized by the fact that they have low selectivity to olefins due to their acidic nature, which causes parasitic reactions, such as isomerization, cracking, coke formation and aromatization, which are typical acid-catalyzed reactions.

The selectivity to olefins increasing slotnik properties.

However, in the literature it is reported (Jiurnal of Physical Chemistry, volume 66, 1962) that the addition of large quantities of alkali metal oxides to improve the selectivity endangering the catalytic properties of compositions: a strong interaction with the chromium oxide suppresses dehydrating activity, while the residual chromium in oxidized state with a valence of more than +3 cannot be restored because it is such a large stable loading of the alkali metal.

Closest to the proposed is a method for olefin hydrocarbons by dehydrogenation of the corresponding paraffin hydrocarbons at elevated temperatures in the presence of a catalyst composition (wt.%):

Cr2O3- 12,2

K2O - 1,4

SiO2- 2

Al2O3- Rest

(RF patent N 1366200, publ. B. I. N 2, 15.01.88 g).

The output of the olefin used in this method is not high enough due to lack of high selectivity of the catalyst.

The problem solved by the present invention is to increase the yield of olefinic hydrocarbon. We propose a method of obtaining olefinic hydrocarbons by dehydrogenation of the corresponding paraffin up up to 1000 h-1in the presence of a catalyst composition (wt. %):

Cr2O3- 6,0 - 30,0

SnO - 0,1 - 3,5

Me2O - 0,4 - 3,0

SiO2- 0,08 - 3,0

Al2O - Rest

where Me is an alkaline metal.

After the stage of dehydrogenation catalyst is sent for regeneration.

Preferred are embodiments of the new method:

- use a catalyst containing Al2O3in the Delta, theta, Delta and theta, theta, and alpha or Delta, theta and alpha phases;

-use the catalyst composition, wt.%:

Cr2O3- 13 - 25

SnO - 0,2 - 2,8

MeO - 0,5 - 2,5

SiO2- 0,08 - 3,0

Al2O3- Rest

where Me is an alkaline metal,

as the alkali metal in the catalyst used potassium;

in the catalyst used Al2O3with a specific surface area less than 150 m2/g;

the dehydrogenation and regeneration is carried out in a fluidized bed of catalyst;

the dehydrogenation in a fluidized bed of catalyst is carried out at a temperature of from 450 to 650oC, atmospheric or slightly higher pressure, flow rate of gas from 100 to 1000 h-1and residence time of the catalyst in the zone pseudois the cation of the catalyst is from 10 to 15 minutes;

when carrying out dehydrogenation and regeneration in the fluidized bed catalyst regeneration is carried out in the presence of air or oxygen or other gas that supports combustion at a temperature above the average temperature of the dehydrogenation and atmospheric or slightly higher pressure, flow rate of gas from 100 to 1000 h-1and residence time of the catalyst is from 5 to 60 minutes.

Use in the claimed method dehydrogenation catalyst, to which was added tin oxide, significantly improves the selectivity to the desired olefin, because additive tin dramatically reduces the formation of the products formed in the acid-catalyzed side reactions.

Process for the catalytic system used in the new method, consists mainly of dispersion of chromium compounds, alkali metal and tin on a medium consisting of aluminum oxide and silicon oxide. Listed below are the techniques of such dispersion. It should be understood that the invention is not restricted by them.

The dispersion can be carried out by impregnation of the specified carrier with a solution containing precursors of the oxides of chromium, potassium and tin, with subsequent drying and calcination, the group given the impregnation according to the method "initial humidity" media solution containing all predecessors of active elements.

As for tin, are other techniques by which it can be added to the catalytic system:

- the addition of tin to the media before dispersing the precursors of the oxides of chromium and potassium;

treatment of solids containing the oxides of chromium and potassium solution containing compounds of tin, ion exchange, impregnation, etc.

- deposition of tin using parasitemia media to Supplement predecessors of chromium oxide and potassium oxide, using a volatile compound substances, which are deposited;

- deposition of tin using parasitemia solid substance containing: oxide of aluminum, chromium oxide, potassium oxide, using a volatile compound substances, which are deposited.

Among the above methods are preferred saprobity carrier with a solution containing the precursors of the active elements: oxides of chromium, potassium and tin, and parasitemia tin.

Both inorganic and organic salts of tin or ORGANOMETALLIC derivatives can be used as precursors of the oxides of divalent and/or tetravalent tin.

solution values that affect their solubility.

Use of ORGANOMETALLIC derivatives, dissolved in organic solvents, in the catalytic system according to the procedures described above.

Regeneration of the catalyst and the proposed method is carried out in an atmosphere of air and/or oxygen with increasing temperature the catalytic system to the corresponding values, for example, by combustion of a suitable fuel. For regeneration must follow the recovery phase of catalyst in order to restore the catalyst to restore the hexavalent chromium formed at the stage of regeneration.

The claimed process can be applied to any dehydrogenation in a fixed, fluidized or moving bed of the catalyst.

Preferably, the process should be carried out in a fluidized bed system in a main part consisting of a reactor, where the reaction and the regenerator, where the catalyst is regenerated by burning on the surface of coke formed on the reaction stage.

In the system of the reactor-regenerator catalyst in a fluidized condition circulates continuously MEA account of the regenerated catalyst, which enters the reactor at a temperature that is above average reaction temperature. In the reactor the catalyst is maintained in fluidized condition by using a reaction gas that enters the catalytic layer from the bottom through a special distribution system.

The reacted gas leaves the reactor from the top after passing system of cyclones or other appropriate systems Department powdery substances; the gas is then routed to a heat exchanger for heating of supply of raw materials, and then in section separation, which allocated the resulting olefins, whereas the unreacted paraffins can be returned to the stage of synthesis, and by-products are separated and can be used in the regenerator as a fuel gas.

If the production after the installation dehydrogenation is the installation of esterification, the section division is used only to remove by-products.

In the reactor the catalyst in the fluidized state moves countercurrent with respect to the gas phase: the gas enters the catalytic layer from the bottom through a distributor, which distributes it to the surface layer. The catalyst exits reachim diameter of the reaction zone, where the gas between the particles, moves and desorbed with the introduction of nitrogen or methane from below, so that displaced or desorbed gas re-enters the reactor, preventing loss of reactants or products.

The catalyst in the fluidized state, then sent pneumatically in the regenerator.

In the reactor in the fluidized bed is preferable to have the following operating conditions:

- maintaining the temperature at 450oC to 650oC using a flow rate of regenerated catalyst, depending on the processed paraffin or mixtures thereof;

- atmospheric pressure or slightly above;

- the volumetric rate of from 100 to 1000 h-1(N liters of gas per hour and liter of catalyst), most preferably from 150 to 200;

- the residence time of the catalyst in the zone of fluidization from 5 to 30 minutes, preferably from 10 to 15 minutes, and in the area of desorption from 0.2 to 10 minutes.

Lattice with a free area of from 10 to 90%, preferably from 20 to 40%, can be installed horizontally inside the reactor at a distance of from 20 to 200 cm from each other.

These grilles are installed to prevent back mixing of gas and Kemaliye conversion of paraffins and selectivity to the desired olefin.

In particular, the selectivity can be increased by using the axial thermal profile, which is placed on the layer of catalyst at high temperature in the upper part, where does the regenerated catalyst, and the minimum temperature at the bottom: the difference in temperature in the layer is preferably from 15 to 65oC.

To optimize the axial thermal profile, you can distribute the regenerated catalyst, changing the height of the catalytic layer. The conveyor system from the reactor to the regenerator consists of a transport line with at least one zone in which the catalyst has a movement in a downward direction and which is supported by the intermediate terms of the minimum fluidization to a minimum the formation of bubbles, by introducing an appropriate quantity of gas at the correct height, and the area where the catalyst has an upward movement until, until it reaches the upper part of the catalyst layer of the regenerator, by introducing a gas into the base, which significantly reduces the density of the fluid.

Preferably, the regenerator of the same size as the reactor.

Appropriate raspredelitel neratzia occurs within the layer due to the burning of coke, deposited on the catalyst, and heating of the catalyst occurs when combustion of methane or fuel gas in the presence of air or oxygen or other fuel gas at a temperature that is above average reactor temperature.

Prior to the filing of the regenerated catalyst to the reactor it is subjected to restoration processing at temperatures from 650 to 680oC for a period of from 0.2 to 10 minutes in order to remove hexavalent chromium, which is formed during the combustion of coke.

In the regenerator the movement of gas and solids is countercurrent: air is supplied to the bottom of the catalytic layer, whereas the fuel gas is supplied to the corresponding height layer.

The gas leaving the regenerator consisting of nitrogen and combustion products can pass through cyclones or other systems located in the upper part of the apparatus for the separation of the accumulated powder, and then after the regenerator can be sent to the heat exchanger for heating air intended for combustion.

Prior to release into the atmosphere, these gases are passed through a system of filters or other devices to reduce the dust content up to several tens of milligrams on the tion of carbon monoxide and nitrogen oxides in the exhaust gas such that does not require further purification.

The operating pressure in the reactor preferably either atmospheric or slightly higher volumetric rate from 100 to 1000 h-1and the residence time of solids in the range of 5 to 60 minutes, most preferably from 20 to 40 minutes.

The regenerated catalyst is passed to the reactor in the same manner as depleted catalyst in the regenerator.

The system of the reactor-regenerator, is designed allows you to maintain constant operating parameters and characteristics during the entire period of the operation and maintenance of installation.

Aliquot share of the catalyst is periodically unloaded from the system and replaced with an equal aliquot shares of fresh catalyst without interrupting the plant operation.

The advantages of the system of the reactor with a fluidized bed of the regenerator can be summarized as follows:

optimal temperature profile in the reactor allows to maximize the yield of olefin;

- heat is transferred directly in the reaction with the regenerated catalyst: the absence of heat exchange surfaces and strong back-mixing fluid is R> - the process in pseudouridine layer does not require recyclo hydrogen which is harmful from a thermodynamic point of view, but necessary in other configurations for temperature control;

all other operations taking place in this process, continuous, and there is no need to modify the operating parameters throughout the life of the installation;

- with regard to the design capacity, the plant can operate with a wide range of flexibility, meaning production capacity:

- reaction and regeneration occur in physically separated areas, and there can be no mixing of hydrocarbon streams with streams containing oxygen:

the process takes place at atmospheric pressure or slightly higher: so the air from the outside cannot penetrate into the reaction zone:

- no special treatment required to reduce the emission of gas pollutants.

The drawing shows a possible use of the reaction-regeneration scheme, described below.

Hydrocarbons (1) are fed into the reactor (A) via the appropriate dispenser (certeze not shown), whereas the gases after the reaction are derived from line (4) of the reactor after por the CSOs layer, and exits the reactor (A), passing through desorber (B) where it comes into contact with desorbers gas (2). Then the catalyst is fed into the transport line (6), on which it is sent to the regenerator (D), specifically in the upper part of the catalytic layer.

In this case presents (3) on one input line, gas transport line. Catalyzatoroprovod stated here, is characterized by a U-shaped connection between the lower and upper part. The catalyst descends through the regenerator (D), enters the reducing agent (E), then in desorber (G), after the transport line (C), and then sent to the reactor. Regenerating air (8), gas combustion, the same as that for the recovery of catalyst (E), and deformirujuschij gas (10) are fed through the respective valves (not shown).

The gases after passing through the cyclones FDgo through (7).

Examples presented here should not be construed as limiting the invention.

Example 1 (comparative)

Microcrystalline pseudoboehmite with the addition of silicon oxide (1.2 wt.%) received size particle diameter of from 5 to 300 microns by spray-drying of a colloidal solution of hydrated aluminum oxide and the cation at a temperature of 450oC for one hour and the second at 1030oC for 4 hours in a stream of dry air.

The resulting product had a specific surface area of 100 m2/g, a porosity of 0.34 cm3/g and consisted mainly of Delta and theta transition alumina with a small amount of alpha alumina.

200 g of this alumina was impregnated, using the technique of "initial" moisture, aqueous solution (68 cm3containing 67,5 g CrO3(and 99.8 wt.%) and 6.4 KOH (90 wt.%) in deionized water at a temperature of 85oC. the Impregnated product was left at room temperature for 1 hour, then dried at a temperature of 90oC for 15 hours. The dried product was activated in a stream of dry air at a temperature of 750oC for 4 hours.

The catalyst having the composition, wt.%:

Cr2O3- 20

K2O - 1,87

SiO2- 1,25

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane in the temperature range of 540 to 580oC. conditions of implementation of the process described below. The results are shown in table 1.

Example 2.

200 g microspherical alumina, obtained as described/SUB> (and 99.8 wt.%) and 6,48 g KOH (90 wt.%) and 4.13 g SnC2O4(to 99.9 wt.%) in deionized water at the same temperature as in example 1.

The impregnated product was treated as described in example 1, obtaining a catalyst of the following composition, wt.%:

Cr2O3- 20

K2O - 1,89

SnO - 0,9

SiO2- 1,23

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane. The results are shown in table 1.

Example 3.

200 g microspherical alumina, obtained as described in example 1, was impregnated by the method described here previously, aqueous solution (68 cm3containing 68,8 g CrO3(and 99.8 wt.%) and 6,52 KOH (90 wt.%) and 5,61 g SnC2O4(to 99.9 wt.%) in deionized water at the same temperature as in example 1.

The impregnated product was treated as described in example 1, obtaining a catalyst of the following composition, wt.%:

Cr2O3- 20

K2O - 1,89

SnO - 1,4

SiO2- 1,22

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane. The results are presented in table 1.

Example 4.

200 g of microscopic on the rum (68 cm3containing 67,9 g CrO3(and 99.8 wt.%) and 6,44 g of KOH (90 wt.%) and 1.78 g SnC2O4(to 99.9 wt.%) in deionized water at the same temperature as in example 1.

The impregnated product was treated as described in example 1, obtaining a catalyst of the following composition, wt.%:

Cr2O3- 20

K2O - 1,89

SnO - 0,45

SiO2- 1,22

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane. The results are shown in table 1.

Example 5.

200 g microspherical alumina, obtained as described in example 1, was impregnated by the method described here previously, aqueous solution (68 cm3containing 67,7 g CrO3(and 99.8 wt.%) and 6.42 per g of KOH (90 wt.%) and of 0.91 g SnC2O4(to 99.9 wt.%) in deionized water at the same temperature as in example 1.

The impregnated product was treated as described in example 1, obtaining a catalyst of the following composition, wt.%:

Cr2O3- 20

K2O - 1,89

SnO - 0,23

SiO2- 1,25

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane. The results are shown in table 1.

Example 6.

3containing 3,99 g dissolved dimethoxytrityl tin (CH3O)2(Sn(C4H9)2in nitrogen atmosphere.

The impregnated product was kept at room temperature for 1 hour, then dried at a temperature of 90oC until complete removal of methanol. The dried product was finally progulivali at 750oC for 4 hours in an atmosphere of dry air.

This was the catalyst composition, wt.%:

Cr2O3- 20

K2O - 1,89

SnO - 0,87

SiO2- 1,23

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane. The results are shown in table 1.

Example 7.

200 g of the catalyst obtained in example 6, modified tin, using methods of parasitemia. To this end, the sample media was loaded in a quartz reactor equipped with a pocket for a thermometer and a ceramic valve with calibrated porosity order to obtain a homogeneous distribution of nitrogen in the bottom layer. The reactor material was placed in a furnace with partial heating and applied nitrogen (40 - 45N l/h) through a porous distributor that supported the fluidization of the material. When dolefil layer, before applying the precursor of tin.

Making sure that the temperature of the homogeneous layer in the range of 1oC in relation to a given temperature, the layer was injected nitrogen, saturated dibutylaminoethanol (CH3O)2(Sn(C4H9)2with a speed of 10 to 15 N l/h and at a temperature of from 150 to 170oC. Saturated flow was applied on top of the reactor through a quartz tube and passed through the catalytic layer and the porous distributor, mixed in the lower part of the septum with nitrogen. The stream exiting the reactor was cooled to highlight unreacted dimetildisiloksana.

The quantity of tin was desirables by weight residual predecessor in the saturator. When the required number of predecessor spent on obtaining theoretical download tin, the work was stopped.

The temperature of the catalytic layer was increased to 750oC and maintained at this level for 4 hours to activate the material. The activated product was analyzed to determine percentage composition, in which the result was as follows, wt.%:

Cr2O3- 20

K2O - 1,89

SnO - 0,33

SiO2- 1,24

Al2O3

Example 8 (comparative)

100 g of the sample pseudoboehmite obtained as in example 1 was subjected to heat treatment as follows: first calcination at 450oC for 1 hour, the second calcination at 1000oC for 4 hours in a stream of dry air. The calcined product had a specific surface area of 130 m2/g, porosity of 0.49 cm3/g and consisted of Delta and theta transition alumina.

150 g of this alumina was impregnated, using the method of initial moisture content, aqueous solution (74 cm3containing 66,8 CrO3(and 99.8 wt.%) and are 5.36 g of potassium carbonate (45 wt.%./wt. KON) and kept at the same temperature as that in example 1. The impregnated product was left at room temperature for 1 hour, then dried at a temperature of 90oC for 15 hours. The dried product was activated in a stream of dry air at a temperature of 750oC for 4 hours.

Got the catalyst composition, wt.%:

Cr2O3- 25

K2O - 1

SiO2- 1,8

Al2O3- Rest

The catalyst used in the process of dehydrogenation of propane at a temperature of from 560 to 600oC. the Results are shown in table 2.

Example 9.

150 the methanol (74 cm3containing 3.75 g dimethoxytrityl tin (CH3O)2(Sn(CH4H9)2.

The impregnated product was kept for 1 hour, then dried at a temperature of 90oC until complete removal of methanol. The dried product was finally progulivali at 600oC for 2 hours in an atmosphere of dry air. The calcined product was impregnated according to the method described in example 8, an aqueous solution (74 cm3containing 67,6 g CrO3(and 99.8 wt.%) and 5.42 g of potassium carbonate (45 wt. %./wt. KON) and kept at the same temperature as in example 1. The resulting catalyst had the following composition, wt.%:

Cr2O3- 25

K2O - 1

SnO - 0,84

SiO2- 1,18

Al2O3- Rest

The catalyst used in the process of dehydrogenation of propane. The results are presented in table 2.

Example 10.

150 g of aluminum oxide used in example 9, was soaked by the method of initial moisture content, as in the example 9, a solution of methanol (74 cm3containing 7,63 g dimethoxytrityl tin (CH3O)2(Sn(C4H9)2. The calcined product under the conditions described in example 9, was soaked by the method described in example 8, water rasri the same temperature, as in example 1. The resulting catalyst had the following composition, wt.%:

Cr2O3- 25

K2O - 1

SnO - 1,68

SiO2- 1,17

Al2O3- rest

The catalyst used in the process of dehydrogenation of propane. The results are shown in table 2.

Example 11.

150 g of the aluminum oxide used in example 9, was soaked by the method of initial moisture content, as in the example 9, a solution of methanol (74 cm3containing to 11.61 g dimethoxytrityl tin (CH3O)2(Sn(C4H9)2. The calcined product under the conditions described in example 9, was soaked by the method described in example 8, an aqueous solution (74 cm3containing 69,2 g CrO3(and 99.8 wt. %) and 5.55 g of potassium carbonate (45 wt.%./wt. KOH) and kept at the same temperature as in example 1. The resulting catalyst had the following composition, wt.%:

Cr2O3- 25

K2O - 1

SnO - 2,52

SiO2- 1,14

Al2O3- Rest

The catalyst used in the process of dehydrogenation of propane. The results are shown in table 2.

Example 12.

150 g of the aluminum oxide used in example 8 was impregnated with an aqueous solution (74 cm3), rbonate potassium (45 wt. %./wt. KOH) and 5.35 g SnC2O4(to 99.9 wt.%./wt.). Drying and activation were performed according to the method described in example 1. The resulting catalyst had the following composition, wt.%:

Cr2O3- 25

K2O - 1

SnO - 1,68

SiO2- 1,5

Al2O3- Rest

The catalyst used in the process of dehydrogenation of propane. The results are shown in table 2.

Example 13.

150 g of the catalyst obtained by the method described in example 8, was soaked with a solution of methanol (39 cm3containing 3.03 g (CH3O)2(Sn(C4H9)2according to the technique described in example 6. The catalyst after activation was analytically to determine its composition and used in the reaction of dehydrogenation of propane. The resulting catalyst had the following composition, wt.%:

Cr2O3- 24,8

K2O - 0,99

SnO - 0,91

SiO2- 1,17

Al2O3- Rest

The results are shown in table 2.

Example 14.

235 g of catalyst was obtained by the method described in example 2, the impregnation 200 grams of aluminum oxide, the same as example 2, an aqueous solution (68 cm3containing 37,2 g CrO3(and 99.8 wt.%) and by 5.87 g KOH (90 wt.%) and 3.26 the left, wt.%:

Cr2O3- 12

SiO2- 1,36

K2O - 1,89

SnO - 0,9

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane. The results are shown in table 1.

Example 15 (comparative)

200 g of aluminum oxide with a specific surface area of 104 m2/g and a porosity of 0.34 cm3/g, obtained by annealing the sample pseudoboehmite according to the method described in example 1, but without the silica was impregnated with an aqueous solution (68 cm3containing 68,3 g CrO3(and 99.8 wt.%) and 6,48 g KOH (90 wt.%) and 4.13 g SnC2O4(99,9%). The resulting catalyst had the following composition, wt.%:

Cr2O3- 20

K2O - 1,89

SnO - 0,9

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane. The results are presented in table 1.

Example 16.

A sample of the catalyst was obtained as in example 2, with the same aluminum oxide, and had the following composition, wt.%:

Cr2O3- 20

K2O - 3

SnO - 0,9

SiO2- 1,22

Al2O3- Rest

The catalyst used in the process of dehydrogenation of isobutane. The results are shown in table 1.

CONDITIONS OF REALIZATION OF PROCESSES OF PRODUCTION OF OLEFINIC HYDROCARBONS

The catalysts obtained in examples 1-17 were used in the fluidized bed in a quartz reactor equipped with a distributor, also made of quartz, with calibrated porosity. The expander is placed on the upper part of the reactor and the function of the braking of the thread, causing small particles to fall back to the catalyst bed. The catalytic cycle that simulates the behavior of an industrial reactor consists of a reaction phase, in which the hydrocarbons are served within 15 minutes; the clean phase when nitrogen is passed for the liberation of the catalyst from the adsorbed products, within 10 minutes; phase regeneration when the regeneration gas (air) is served within 30 minutes (in these experiments); phase washing with nitrogen for at least 10 minutes, with subsequent reaction phase for 15 minutes. Specifications industrial process dehydrogenation in a fluidized bed e regeneration and restoration was carried out at 650oC, whereas the reaction was carried out in the temperature range from 560 to 600oC for the dehydrogenation of propane and from 540 to 580oC in the case of dehydrogenation of isobutane.

Space velocity of the reactants has a value of 400 l/cat. hour. When first using each catalyst to the reaction dehydrogenation restored according to the described method.

The reagent is directed into the reactor, dotirovala weight.

Flows originating from the reactor during the reaction and the clean phase, is passed first through a cold trap for trapping heavy products, weight, carbon and hydrogen % of which was determined, and then collected in multilayer soft tank for samples that have no affinity to hydrocarbons. The contents of the reservoir measured volumetrically pump and analyzed by gas chromatography.

And finally after 10 minutes of cleaning with nitrogen, the sample of catalyst is taken to determine the number of formed coke. The data thus obtained were entered into a personal computer to calculate the material balance conversion and selectivity of various products.

1. The way to obtain olefinic hydrocarbons by dehydrogenation of courzieu, characterized in that the use of the catalyst composition, wt.%:

Cr2O3- 6,0 - 30,0

SuO - 0,1 - 3,5

MeO - 0,4 - 3,0

SiO2- 0,08 - 3,0

Al2O3- Rest

where Me is an alkaline metal,

and the dehydrogenation is carried out at a temperature of from 450 to 800oC, a pressure of from 0.1 to 3 ATM.abs. and flow rate of gas from 100 to 1000 h-1.

2. The method according to p. 1, characterized in that the use of catalyst containing Al2O3in the Delta, theta, Delta and theta, theta, and alpha or Delta, theta and alpha phases.

3. The method according to p. 1, characterized in that the use of the catalyst composition, wt.%:

Cr2O3- 13 - 25

SuO - 0,2 - 2,8

Me2O - 0,5 - 2,5

SiO2- 0,08 - 3,0

Al2O3- Rest

where Me is an alkaline metal.

4. The method according to p. 1, characterized in that the use of catalyst containing as an alkali metal is potassium.

5. The method according to p. 1, characterized in that the use of Al2O3with a specific surface area less than 150 m2/,

6. The method according to p. 1, characterized in that the dehydrogenation and regeneration is carried out in a fluidized bed of a catalyst.

7. The method according to p. 6, characterized in that degidrirovanie the STI gas from 100 to 1000 h-1and residence time of the catalyst in the zone of fluidization from 5 to 30 minutes

8. The method according to p. 7, characterized in that the volumetric rate of gas from 150 to 200 h-1, and the residence time of the catalyst in the zone of fluidization 10 to 15 minutes

9. The method according to p. 6, characterized in that the regeneration of the catalyst is carried out in the presence of air, oxygen or other gas that supports combustion at a temperature above the average temperature of the dehydrogenation and atmospheric or slightly higher pressure, flow rate of gas from 100 to 1000 h-1and residence time of the catalyst in the regeneration zone from 5 to 60 minutes

 

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The invention relates to chromium catalysts for the trimerization and/or polymerization of olefins

The invention relates to the production of catalysts for processing of hydrocarbon raw materials and can be used in the process of hydrodealkylation benzene-toluene-xylene (BTX) fraction allocated from the pyrolysis condensate fraction in the pyrolysis of hydrocarbons
The invention relates to the field of cooking chromium catalysts used for a wide range of catalytic processes, for example, conversion, digidrive, origene, polymerization and other

The invention relates to the production of a heterogeneous catalyst, in particular for the catalyst of liquid-phase biocatalytic oxidation of sulfur and organic compounds, and can be used for wastewater treatment in biological treatment stage in the refining, petrochemical, gas and pulp and paper industries

The invention relates to catalysts for the polymerization of olefins containing inorganic chromium compound on a carrier of silica gel

The invention relates to catalytic chemistry, in particular to catalysts for deep oxidation of hydrocarbons, and can be used in the chemical and petrochemical industry

The invention relates to a process for the preparation of cyanopyridines oxidative ammonolysis of alkylpyridine
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