Catalyst for dehydrogenation of isopentane and isopentane-isoamylene fractions and method of preparing said catalyst

FIELD: chemistry.

SUBSTANCE: invention relates to organic chemistry and petrochemistry, particularly to designing and using catalysts. Described is a catalyst for dehydrogenation of isopentane and isopentane-isoamylene fractions based on platinum and tin, deposited on a carrier - zincalume spinel. The catalyst is distinguished by that, the carrier is in form of nanocrystalline particles with average crystal size of 22-35 nm with components in the following ratio, wt %: platinum - 0.05-2.0, tin - 0.1-6.0, zincalume spinel - the rest. Also described is a method of preparing said catalyst, involving grinding and mixing oxygen-containing zinc and aluminium compounds, gradual addition of water until obtaining a homogeneous pasty mass, stirring and moulding, drying the granules at room temperature and calcination, subsequent saturation of the formed carrier with an aqueous solution of platinum and tin compounds, final drying of the catalyst mass in air; the method is distinguished by that, the carrier is calcined while gradually raising temperature to 800-900°C at a rate of 10-200°C/hour, and then for 5-40 hours at 850-1000°C, while constantly controlling size of the formed crystals until formation of nanocrystalline particles with average crystal size of 22-35 nm.

EFFECT: increased efficiency of dehydrogenation process due to increased output of isoprene, with high selectivity on dehydrogenation products, as well as due to longer inter-regeneration period of the catalyst.

3 cl, 1 tbl, 14 ex

 

The invention relates to the field of organic chemistry and petrochemicals, in particular to the development and use of catalysts for the dehydrogenation of paraffin hydrocarbons fraction C3-C5and the corresponding olefinic hydrocarbons to obtain a diene hydrocarbons, in particular isoprene.

Processes for the dehydrogenation of paraffin hydrocarbons are the most large-scale in the technology of petrochemical and organic synthesis, allow to obtain unsaturated compounds used as monomers for the production of synthetic rubbers, plastics, high-octane components of fuels and other valuable products.

The reaction of dehydrogenation of paraffins with the formation of mono - and diolefins proceeds in the presence of catalysts at temperatures above 500°C. the Process is governed by thermodynamic equilibrium and is carried out in two ways, which are based on the principle of shifting the equilibrium by reducing the partial pressure of the source components by either vacuum or dilute raw materials inert gas.

Known catalyst, developed by Gudri used during single-stage vacuum dehydrogenation of isopentane or isopentane-isoamylene fractions [OGO S. Kaliev, Idlis G.S. isoprene Production. L.: Chemistry. 1973, S-171; US 3088986, A1, 193.05.07]. The catalyst is a tablet with a size of 4×4 mm consisting of aluminum oxide impregnated with 20 wt.% oxide of chromium. In the presence of this catalyst, the process occurs at a temperature 535-650°C, the pressure of 0.16 to 0.21 MPa. After each cycle carry out the restoration of the hydrogen within 5-9 minutes Yield of isoprene on missed raw materials (isopentane) is 12.8 wt.% when selectivity of about 52% and a conversion of 30%.

The main disadvantage of this catalyst is that the prescribed life span of only 6 months. After unloading from the reactor, the catalyst must be disposed of, and the presence of toxic substances in the form of chromium compounds in the catalyst retains the problem of ecological danger. A significant drawback is the short cycle of the catalyst (5-9 minutes), after which it needs to regenerate. In addition, the process is conducted under vacuum conditions, which significantly complicates the process flow and has low yields of isoprene, selectivity and conversion.

To reduce coke formation and reducing the proportion of adverse reactions proposed a catalyst comprising the oxide of chromium, where the media use aluminium spinel [EN 2188073, C2, 2002.08.27]. The catalyst has the following content of components in terms of oxides, wt.%: Cr2O 10,0-30,0, ZnO 30,0-45,0, Al2O3the rest of it.

To improve the efficiency of the process of dehydrogenation of paraffin hydrocarbons, such as isobutane and propane, a catalyst which additionally contains active components in the form of tin oxide and platinum [EN 2183988, C1, 2002.06.27], having the following composition, wt.%: Cr2O310,0-30,0, ZnO 30,0-45,0, SnO20,1-3,0, Pt Of 0.005 To 0.2, Al2O3the rest of it. Media produced by long (2-16 hours) mixing the oxides of aluminum and zinc oxalate or tin oxide and water in a ball or bead mill at a temperature of 20-50°C with subsequent heat treatment of the formed suspension for 6 hours at 120°C and annealing for 3-4 hours at 1050-1100°C in a stream of air. Next, obtain catalysts with a particle diameter of 5-250 microns by spray-drying the suspension, consisting of media, oxide of chromium (VI)solution of hexachloroplatinic acid and water under stirring for 2-5 hours at a temperature of 20-50°C. the Catalyst is subjected to heat treatment consisting of annealing at 680-760°C for 3-5 hours in a stream of air.

The disadvantage of the above catalysts is their content of toxic compounds Cr2O3which is a source of environmental pollution.

Known use is as a catalyst for dehydrogenation of paraffin hydrocarbons at atmospheric pressure in the environment of water vapor of platinum-containing catalysts, obtained by applying compounds of platinum and tin on spinel media [SU 1001545 A1, 2000.08.27; SU 1103405 A1, 2000.05.27; SU 1511894 A1, 1999.10.20; SU 665625 A1, 2001.06.10; SU 635652 A1, 2001.04.10].

To improve the activity and selectivity towards formation of diene and olefin hydrocarbons at the stage of mixing aluminum hydroxide with zinc oxide in the catalyst is injected compounds of the alkali metal in the form of ortho - or pyrophosphate potassium or cesium [SU 1001545 A1, 2000.08.27]. A mixture of aluminium hydroxide with zinc oxide is carried out in the presence of water to education plastic mass, then hold its formation, air-dried and calcined, followed by impregnation of the support with an aqueous solution of hexachloroplatinic acid and inorganic compounds of tin with final drying of the catalyst mass in the air.

Known catalyst of similar composition with increased strength and activity [SU 1103405 A1, 2000.05.27], the distinguishing feature of which is the introduction at the stage of formation of spinel burnable media supplements of polydivinylbenzene or copolymer of styrene and divinylbenzene.

A similar effect was obtained using the process of dehydrogenation catalyst platinum source on Galvalume ® media prepared using as a zinc-containing component is a mixture of zinc oxide and chlorite is and zinc in a ratio of from 1:1 to 20:1 [SU 635652 A1, 2001.04.10].

It is known that the dehydrogenation of acyclic hydrocarbons to increase the activity of the catalyst containing aluminium spinel, platinum, zinc oxide and tin dioxide, additionally injected manganese oxide in the following ratio, wt.%: platinum is 0.1-0.5; zinc oxide 0.5 to 10; tin dioxide of 0.3-5; oxide of manganese, from 0.3 to 5; aluminium spinel else [SU 1511894 A1, 1999.10.20].

The closest analogue to the catalyst is the catalyst for dehydrolase paraffin and olefin hydrocarbons on the basis of platinum, tin and compounds of alkali or alkaline-earth metal on the carrier - Galvalume ® or alumomagnesium spinel, where as compounds of alkali or alkaline-earth metal it contains silicate or chloride in the following ratio of components: platinum 0,1-5,0; tin, 0.1 to 5.0; a silicate or a chloride of alkali or alkaline-earth metal is 0.1 to 5.0; Galvalume ® or alumomagnesium spinel else [SU 665625 A1, 2001.06.10].

The closest analogue of the method of obtaining the claimed catalyst is a method in accordance with SU 1001545 "Method of producing catalyst for dehydrogenation and dehydrocyclization acyclic hydrocarbons", MPK7 B01J 37/04, 27/18, SS 5/32, publ. 27.08.2000. In accordance with the specified method, the catalyst is obtained by mixing the hydroxide of aluminum oxide qi is ka in the presence of water to education plastic mass, its formation, air drying and calcination followed by impregnation of the formed carrier with an aqueous solution of hexachloroplatinic acid and the introduction of inorganic compounds tin with final air drying the catalyst mass.

The disadvantage in the use of these platinum-tin catalysts obtained by the above described methods, is the low efficiency of the process of dehydrogenation of isopentane, due to both high intensity and low yield of isoprene and insufficiently high selectivity for dehydrogenation products, which leads to a significant consumption of raw materials and energy when carrying out dehydrogenation. In addition, this catalyst quickly sakakawea, which leads to frequent regenerations, therefore, to additional energy costs of regeneration.

The objectives of the present invention is the development of:

the catalytic dehydrogenation of paraffin hydrocarbons, in particular isopentane and isopentane-isoamylene fractions, which can increase the efficiency of the process by increasing the output of diene hydrocarbons, in particular isoprene, with high selectivity for dehydrogenation products, as well as by increasing mezhregionalnogo period of the catalyst;

the way to obtain this effective ka is alistor.

The tasks are solved:

1. The development of a catalyst for the dehydrogenation of isopentane and isopentane-isoamylene fractions on the basis of platinum and tin supported on a carrier containing aluminium spinel, which feature is the media, representing the nanocrystalline particles with an average size of crystallites 22-35 nm at the following content, wt.%:

platinum 0,05-2,0

tin 0,1-6,0

aluminium spinel else

2. The method of obtaining the claimed catalyst comprising grinding and mixing oxygen-containing compounds of zinc and aluminum, the gradual addition of water until a homogeneous pasty mass, mixing and forming, drying the granules at room temperature and annealing, subsequent impregnation of the formed carrier with an aqueous solution of compounds of platinum and tin, the final air drying the catalyst mass, which feature is conducting drying granules media at 100-200°C for 1-10 hours after drying at room temperature, the annealing medium is carried out in the mode of a gradual rise of temperature up to 800-900°C with a speed of 10-200°C/h, then for 5-40 hours at 850-1000°C under constant control of the particle size of the formed crystallites of the medium before the formation of nanocrystalline frequent the C with an average crystallite size 22-35 nm, and calcining the obtained catalyst at 400-500°C for 1-5 hours after drying.

The technical result of the invention is determined by the structural characteristics of the obtained catalyst: nanocrystalline structure of the media can effectively intercalated in the interlayer space, and securely fastened to the surface components of the catalyst, which determines its high activity and selectivity under given conditions of temperature, pressure, velocity flows of raw material dehydrogenation process, and also provides resistance to coking of the catalyst during the process of dehydrogenation in a long time, which leads to an increase mezhregionalnogo period and, accordingly, reduction of steam consumption and reduce energy costs in the process of dehydrogenation.

The average size of nanocrystallites or the average size of coherent scattering regions D(OKP) calculated from the data of x-ray on the broadening of the diffraction peak using the formula Selyakova-sherrer:

nm

where λ is the wavelength of x-rays, nm, β is the integral width of the diffraction line profile, or physical broadening happy. [X-ray and electron-optical analysis. Sagarai, Waskow, LN. Rastorguev.: The textbook. The settlement of the manual for high schools. - 4th ed. Dope Rev.):MISA. 2002. - 360 S.].

The phase composition of the medium is determined by the method of x-ray diffraction. Taking radiographs performed using long-wave radiation CuKαand a graphite monochromator on the diffracted beam. The range of entry angles 2θ scale is from 5 to 95 deg.

The media claimed catalyst has a value of external specific surface area of more than 1 m2/year

The total specific surface area and pore volume determined by the method of low-temperature nitrogen adsorption (BET). The essence of the method of determining the parameters of the porous system described in the method of ASTM D 3663-99 "Standard method of investigation of the surface area and pore volume of catalysts and catalysts carriers".

The catalyst has a bulk density in the range of 0.80-1.10 g/cm3. Bulk density of the catalyst is determined according to THE 2173-075-00206457-2007 "the Catalyst for the dehydrogenation of light paraffin hydrocarbons (CBI)".

The process of dehydrogenation of C3-C5paraffin hydrocarbons with the use of the inventive catalyst is carried out at a temperature of 560-620°C, flow rate of feed 300-500 h-1in the presence of hydrogen and water vapor. The ratio of raw materials:hydrogen:steam is 1:0.5 to 2.0:5-20 mol:mol:mol. The process is carried out in a reactor with a fixed bed of catalyst. PR is the process cycles are: dehydration - the regeneration. The regeneration is carried out vapor mixture at a temperature of 600-640°C until the content of carbon dioxide CO2in the regeneration gases will not decrease to a value of not more than 0.1 wt.%. Contact gas (outlet gas from the reactor after dehydrogenation) analyze by gas chromatography. According to the results of chromatographic analysis calculate the yield of the target isoprene and isoamylene (missed and decomposed paraffin - activity and selectivity of the catalyst, respectively).

According to the results of chromatographic analysis calculate the mass content of CO2, which is then converted to volumetric content of CO2using the correction factor.

Catalytic indicators: yield of isoprene on missed raw materials (EAP) and the yield of isoprene on the decomposed raw material (BP) is calculated on the basis of chromatographic analysis of the raw materials and reaction products.

The yield of isoprene on missed isopentane (EAP wt.%) calculated by the formula

where C(iC5H8)to/gas- mass fraction of isoprene in the contact gas, wt.%;

(IC5H12)raw materials- mass fraction of isopentane in the feed, wt.%;

C(iC5H8)raw materials- mass fraction of isoprene in raw materials, wt.%.

The output of isoamylenes on missed isopentane (BP, wt.%) calculate formula

where C(iC5H10)to/gas- mass fraction of isoamylenes in contact with gas, wt.%;

(IC5H10)raw materials- mass fraction of isoamylenes in raw materials, wt.%;

(IC5H12)raw materials- mass fraction of isopentane in the feed, wt.%;

(IC5H12)to/gas- mass fraction of isopentane in the contact gas, wt.%.

The output of unsaturated hydrocarbons (isoprene + isoamylene) for missing feedstock - isopentane (EAP unintended., wt.%) calculated by the formula

where C(iC5H8)to/gas- mass fraction of isoprene in the contact gas, wt.%;

C(iC5H10)to/gas- mass fraction of the sum of isabelino in contact with gas, wt.%;

(IC5H12)raw materials- mass fraction of isopentane in the feed, wt.%.

The output of unsaturated hydrocarbons (isoprene + isoamylene) on the decomposed raw material - isopentane (BPunintentionally, wt.%) calculated by the formula

where C(iC5H8)to/gas- mass fraction of isoprene in the contact gas, wt.%;

C(iC5H10)to/gas- mass fraction of the sum of isoamylenes in contact with gas, wt.%;

C(iC5H12)raw materials- mass fraction of isopentane in the feed, wt.%;

C(iC5H12)to/gas- mass fraction of isopentane in the contact gas, wt.%.

Conversion (deep transformation) (K, %) as the ratio of the yield of isoprene on missing and decomposed raw materials are calculated according to the formula

The invention is confirmed by examples of specific performance, which together with the obtained results are shown in the table.

Example 1

For the preparation of catalyst No. 1 carefully grind in a mortar 78,08 g of zinc oxide (0.96 mol) and 400,0 g of aluminum hydroxide content (Al2O3)=0,00241 mol/g (0.96 mol), followed by stirring gradually add 70 ml distillirovannoi water until a homogeneous pasty mass. The resulting mass ekstragiruyut, the result of the granules of cylindrical shape with a diameter of 2.0 mm and a length of 5.0 mm, the Obtained granules are dried at room temperature for 20 hours, and then calcined in a muffle furnace in the mode of a gradual rise of temperature up to 900°C at 50°C/hour. Thereafter calcined sample for another 20 hours at 900°C and 15 hours at 950°C.

The resulting carrier has the following characteristics: bulk density of 0.95 g/cm3the size of nanocrystallites of 31.5 nm.

25,00 g of the obtained carrier is impregnated with a solution consisting of 11 ml of a solution of hexachloroplatinic acid (H2PtCl6(T(Pt)=0,01138 g/ml) and 15.0 ml of a solution of tin chloride SnCl2(T=0,028917 g/ml). Received catalysis is Thor dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 0.50 wt.%, Sn of 0.91 wt.%, aluminium spinel with the size of the nanocrystals to 31.5 nm 98,59.

The process of dehydrogenation of isopentane and isopentane-isoamylene fractions is carried out in a flow quartz tubular reactor at the reaction temperature of 580°C, space velocity of the hydrocarbon 400 h-1, molar ratio of raw materials: hydrogen:steam = 1:1:12,5.

In the reaction of dehydrogenation of isopentane and isopentane-isoamylene fractions obtained the following results: PG(isoprene) = 16,49 wt.%, EAP(isoamylene) = 27,08 wt.%, BP(isoprene + isoamylene) = 86,63 wt.%, conversion 46.81 / bbl%.

Example 2

The carrier for catalyst No. 2, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 800°C at 50°C/hour. Thereafter calcined sample 10 h at 800°C and 10 h at 900°C. the resulting carrier has the following characteristics: bulk density of 0.85 g/cm3the size of the nanocrystallites 26,0 nm.

The carrier impregnated conduct similar to that described in example 1 method. The catalyst after drying, calcined at 400°C for 5 hours.

The resulting catalyst has the composition: Pt 0.50 wt.%, Sn of 0.91 wt.%, aluminium spinel with the size of the nanocrystallites 26,0 the m 98,59.

The dehydrogenation process is conducted under the conditions described in example 1, the results are given in the table below:

EAP(isoprene) = 18,30 wt.%, EAP(isoamylene) = 33,70 wt.%, BP(isoprene + isoamylene) = 84,05 wt.%, conversion 61,87%.

Example 3

The carrier for catalyst No. 3, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 800°C at 50°C/hour. Thereafter calcined sample 10 h at 800°C and 20 hours at 900°C.

The resulting carrier has the following characteristics: bulk density of 0.95 g/cm3the size of nanocrystallites of 28.3 nm.

The carrier impregnated conduct similar to that described in example 1 method. The resulting catalyst is dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 0.50 wt.%, Sn of 0.91 wt.%, aluminium spinel with the size of the nanocrystallites 28,3 nm 98, 59.

The dehydrogenation process is conducted under the conditions described in example 1, the results are given in the table below:

EAP(isoprene) = 16,36 wt.%, EAP(isoamylene) = 39,20 wt.%, BP(isoprene + isoamylene) = 83,90 wt.%, conversion 66,27%.

Example 4

The carrier for catalyst No. 4, obtained as described in example 2 method has the following characteristics: bulk density of 0.85 g/cm3that size is of nanocrystallites 26,0 nm.

25,00 g of the obtained carrier is impregnated with a solution consisting of 11,0 ml H2PtCl6(T(Pt) = 0,01138 g/ml) and 25.0 ml of a solution of SnCl2(T=0,028917 g/ml). The resulting catalyst is dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 0.50 wt.%, Sn of 1.52 wt.%, aluminium spinel with the size of the nanocrystallites 26,0 nm 97,98.

The dehydrogenation process is conducted under the conditions described in example 1, the results are given in the table below:

EAP(isoprene) = 15,65 wt.%, EAP(isoamylene) = 25,65 wt.%, BP(isoprene + isoamylene) = 83,82 wt.%, conversion 49,10%.

From these results it follows that for catalysts with the size of the nanocrystallites 26,0 nm with the increasing content of promoter (tin) catalytic activity remains high.

Example 5

The carrier for catalyst No. 5, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 800°C at a rate of 10°C/hour. Thereafter calcined sample 10 h at 800°C and 30 hours at 850°C.

The resulting carrier has the following characteristics: bulk density of 0.85 g/cm3the size of nanocrystallites of 27.7 nm.

25,00 g of the obtained carrier is impregnated with a solution consisting of 2.4 ml of a solution of H2PtCl6(T(Pt)=0,01138 g/ml), 3,9 the l solution of SnCl 2(T=0,028917 g/ml) and 10.0 ml of water. The resulting catalyst is dried at 130°C for 5 hours, then calcined at 500°C for 2 hours.

The resulting catalyst has the composition: Pt of 0.10 wt.%, Sn of 0.18 wt.%, aluminium spinel with the size of the nanocrystallites of 27.7 nm 99,72.

The process of dehydrogenation of isopentane and isopentane-isoamylene fractions is carried out in a flow quartz tubular reactor at the reaction temperature of 600°C, space velocity of the hydrocarbon 500 h-1, molar ratio of raw materials:hydrogen:steam = 1:1,5:10. The results are given in the table below:

EAP(isoprene) = 15,42 wt.%, EAP(isoamylene) = 28,98 wt.%, BP(isoprene + isoamylene) = 83,90 wt.%, conversion 52,92%.

From the above results show that catalysts with the size of the nanocrystallites of 27.7 nm even when the reduction in the content of the active component (platinum) 5 times the catalytic activity remains high.

Example 6

The carrier for catalyst No. 6, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 1100°C at 50°C/hour. Thereafter calcined sample 10 hours at 1100°C.

The resulting carrier has the following characteristics: bulk density of 1.10 g/cm3the size of nanocrystallites of 47.1 nm.

The carrier impregnated spend Ana is ogino described in example 1 method.

The resulting catalyst is dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst had a composition: Pt 0.50 wt.%, Sn of 0.91 wt.%, aluminium spinel with the size of the nanocrystallites of 47.1 nm 98,59.

The dehydrogenation process is conducted under the conditions described in example 1, the results are given in the table below:

EAP(isoprene) = 0,05 wt.%, EAP(isoamylene) = 0,40 wt.%, BP(isoprene + isoamylene) = a 90.0 wt.%, conversion of 0.50%.

This example demonstrates that when the crystallite size is more than 35 nm, the catalytic activity is not present.

Example 7

The carrier for catalyst No. 7, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 800°C at 50°C/hour. Thereafter calcined sample 20 hours at 800°C.

The resulting carrier has the following characteristics: bulk density of 1.00 g/cm3the size of the nanocrystallites 21,8 nm.

The carrier impregnated conduct similar to that described in example 1 method.

The resulting catalyst is dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 0.50 wt.%, Sn of 0.91 wt.%, aluminium spinel with the size of the nanocrystallites 21,8 nm 98,59.

The dehydrogenation process is conducted under the conditions described the data in example 1, the results are given in the table below:

EAP(isoprene) = 10,37 wt.%, EAP(isoamylene) = 12,05 wt.%, BP(isoprene + isoamylene) = 91,89 wt.%, conversion 25,08%.

As can be seen from the given data, the crystallite size of less than 22 nm, the catalytic activity decreases.

Example 8

The carrier for catalyst No. 8, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 800°C at 50°C/hour. Thereafter calcined sample 10 h at 800°C and 10 hours at 850°C. the resulting carrier has the following characteristics: bulk density of 0.80 g/cm3the size of nanocrystallites of 20.5 nm.

The carrier impregnated conduct similar to that described in example 1 method. The resulting catalyst is dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 0.50 wt.%, Sn of 0.91 wt.%, aluminium spinel with the size of the nanocrystallites of 20.5 nm 98,59.

The dehydrogenation process is conducted under the conditions described in example 1, the results are given in the table below:

EAP(isoprene) = 12,37 wt.%, EAP(isoamylene) = 19,81 wt.%, BP(isoprene + isoamylene) = 76,65 wt.%, conversion 62,10%.

As can be seen from the above results, when the crystallite size is less than 22 nm decreases not only the catalytic activity, but the selectivity for dehydrogenation products.

Example 9

The carrier for catalyst No. 9, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 900°C at a rate of 10°C/hour. Thereafter calcined sample 14 h at 900°C and 10 hours at 950°C. the resulting carrier has the following characteristics: bulk density of 0.92 g/cm3the size of nanocrystallites of 30.7 nm.

The carrier impregnated carried out with a solution consisting of 11 ml H2PtCl6(T(Pt)=0,01138 g/ml) and 10.0 ml of a solution of SnCl2(T=0,028917 g/ml). The resulting catalyst is dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 0.50 wt.%, Sn and 0.61 wt.%, aluminium spinel with the size of the nanocrystallites of 30.7 nm 98,89.

The dehydrogenation process is conducted under the conditions described in example 1, the results are given in the table below:

EAP(isoprene) = 16,19 wt.%, EAP(isoamylene) = 31,76 wt.%, BP(isoprene + isoamylene) = 83,86 wt.%, conversion 57,18%.

Example 10

The carrier for catalyst No. 10 obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 800°C at a rate of 10°C/hour. Thereafter calcined sample 10 hours at 800°C and 15 hours at 850°C.

Received but Italy has the following characteristics: bulk density of 0.90 g/cm 3the size of nanocrystallites of 35.0 nm.

The carrier impregnated conduct similar to that described in example 1 method.

The resulting catalyst is dried at 130°C for 3 hours, then calcined at 500°C for 3 hours.

The resulting catalyst has the composition: Pt of 0.05 wt.%, Sn 0.10 wt.%, aluminium spinel with the size of the nanocrystallites of 35.0 nm of 99.85.

The dehydrogenation process is conducted under the conditions described in example 1, the results are given in the table below:

EAP(isoprene) = 15,65 wt.%, EAP(isoamylene) = 25,71 wt.%, BP(isoprene + isoamylene) = 83,81 wt.%, conversion 49,35%.

From the above results show that catalysts with the size of the nanocrystallites of 35.0 nm even when the reduction in the content of the active component (platinum) 10 times the catalytic activity remains high.

Example 11

For the preparation of catalyst No. 11 carefully grind in a mortar 78,08 g of zinc oxide (0.96 mol) and 400,0 g of aluminum hydroxide content (Al2O3)=0,00241 mol/g (0.96 mol), followed by stirring gradually add 70 ml of distilled water to obtain a homogeneous pasty mass. The resulting mass ekstragiruyut, the result of the granules of cylindrical shape with a diameter of 2.0 mm and a length of 5.0 mm, the Obtained granules are dried at room temperature for 10 hours, and then calcined in a muffle furnace at p is the bench gradual rise in temperature to 900°C at a rate of 100°C/hour. Thereafter calcined sample for another 20 hours at 900°C and 20 hours at 950°C.

The resulting carrier has the following characteristics: bulk density of 0.95 g/cm3the size of nanocrystallites of 29.3 nm.

The carrier impregnated conduct similar to that described in example 1 method.

The resulting catalyst is dried at 110°C for 4 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 2.0 wt.%, Sn 6.00 wt.%, aluminium spinel with the size of the nanocrystallites of 29.3 nm 92,0.

The process of dehydrogenation of isopentane and isopentane-isoamylene fractions is carried out in a flow quartz tubular reactor at the reaction temperature of 580°C., space velocity of the hydrocarbon 400 h-1, molar ratio of raw materials:hydrogen:steam = 1:0,5:20.

In the reaction of dehydrogenation of isopentane and isopentane-isoamylene fractions obtained the following results: PG(isoprene) = 16,30 wt.%, EAP(isoamylene) = 25,65 wt.%, BP(isoprene + isoamylene) = 84,10 wt.%, conversion 49,88%.

Example 12

For the preparation of catalyst No. 12 carefully grind in a mortar 78,08 g of zinc oxide (0.96 mol) and 400,0 g of aluminum hydroxide content (Al2O3) = 0,00241 mol/g (0.96 mol), followed by stirring gradually add 70 ml of distilled water to obtain a homogeneous pasty mass. Continue stirring another is 30 minutes The resulting mass ekstragiruyut, the result of the granules of cylindrical shape with a diameter of 2.0 mm and a length of 5.0 mm, the Obtained granules are dried at room temperature for 20 hours, and then calcined in a muffle furnace in the mode of a gradual rise of temperature up to 900°C at 50°C/hour. Thereafter calcined sample for another 20 hours at 900°C for 25 hours at 950°C. and 5 hours at 1000°C.

The resulting carrier has the following characteristics: bulk density of 0.95 g/cm3the size of the nanocrystallites 32,0 nm.

The carrier impregnated conduct similar to that described in example 1 method.

The resulting catalyst is dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 0.5 wt.%, Sn of 0.91 wt.%, aluminium spinel with the size of the nanocrystallites 32,0 nm 98,59.

The process of dehydrogenation of isopentane and isopentane-isoamylene fractions is carried out in a flow quartz tubular reactor at the reaction temperature of 580°C, space velocity of the hydrocarbon 400 h-1, molar ratio of raw materials:hydrogen:steam = 1:1:12,5.

In the reaction of dehydrogenation of isopentane and isopentane-isoamylene fractions obtained the following results: PG(isoprene) = 16,03 wt.%, EAP(isoamylene) = 27,12 wt.%, BP(isoprene + isoamylene) = 85,13 wt.%, conversion 50,69%.

Example 13

The media was pushing the jam No. 13, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 800°C at 50°C/hour. Thereafter calcined sample 10 hours at 800°C and 10 hours at 850°C.

The resulting carrier has the following characteristics: bulk density of 0.95 g/cm3the size of the nanocrystallites 22 nm.

The carrier impregnated conduct similar to that described in example 1 method.

The resulting catalyst is dried at 130°C for 1 hour, then calcined at 500°C for 3 hours.

The resulting catalyst has the composition: Pt 0.5 wt.%, Sn of 0.91 wt.%, aluminium spinel with the size of the nanocrystallites of 22.0 nm 98,59.

The dehydrogenation process is conducted under the conditions described in example 1, the results are given in the table below:

EAP(isoprene) = 14,61 wt.%, EAP(isoamylene) = 26,84 wt.%, BP(isoprene + isoamylene) = 84,50 wt.%, conversion 49,04%.

Example 14

The carrier for catalyst No. 14, obtained as described in example 1, after drying at room temperature and calcined in a muffle furnace in the mode of a gradual rise of temperature up to 900°C at a rate of 10°C/hour. Thereafter calcined sample 14 h at 900°C and 10 hours at 950°C. the resulting carrier has the following characteristics: bulk density of 0.92 g/cm3the size of nanocrystallites of 30.7 nm.

<> The carrier impregnated carried out with a solution consisting of 11,0 ml H2PtCl6(T(Pt)=0,01138 g/ml) and 10.0 ml of a solution of SnCl2(T=0,028917 g/ml). The resulting catalyst is dried at 130°C for 2 hours, then calcined at 500°C for 1 hour.

The resulting catalyst has the composition: Pt 0.50 wt.%, Sn - 0,61 wt.%, aluminium spinel with the size of the nanocrystallites of 30.7 nm 98,89 wt.%.

The dehydrogenation process is conducted in the following conditions: a reaction temperature of 600°C., space velocity of the hydrocarbon 300 h-1, molar ratio of raw materials:hydrogen:steam = 1:2:5, the results are given in the table below:

EAP(isoprene) = 15,61 wt.%, EAP(isoamylene) = 26,00 wt.%, BP(isoprene + isoamylene) = 84,02 wt.%, conversion 49,52%.

As seen from the above examples, the proposed catalyst for the dehydrogenation of isopentane and isopentane-isoamylene fractions allows to increase the efficiency of the process due to more complete conversion of the original paraffins with high selectivity diolefin hydrocarbons.

Increased activity. catalyst due to the optimization of the structural characteristics of the catalyst. The use of a catalyst with an optimum structure can reduce the energy cost of the process due to the longer cycle of dehydrogenation.

Thus, a new the th catalyst for the dehydrogenation of isopentane and isopentane-isoamylene fractions, and how to obtain it. As a result of use of the inventive catalyst in the dehydrogenation of paraffin hydrocarbons, the process is more efficient, which is reflected in (1) increasing the yield of diene and olefin hydrocarbons due to the use of highly active and selective catalyst from the dense packing of nanocrystalline particles in the granules aluminium spinel carrier; (2) the decrease of expenditure norms of raw materials due to the increase of the yield of the target products; (3) reduction in energy costs due to the increased period between regenerations, due to the stable operation of the catalyst and more resistant to coking.

1. Catalyst for dehydrogenation of isopentane and isopentenyladenosine fractions on the basis of platinum and tin supported on a carrier - aluminium spinel, characterized in that the carrier is a nanocrystalline particles with an average size of crystallites 22-35 nm at the following content, wt.%:

2. A method of producing a catalyst for dehydrogenation of isopentane and isopentenyladenosine fractions, including grinding and mixing oxygen-containing compounds of zinc and aluminum, the gradual addition of water until a homogeneous pasty mass, mixing and forming, drying the granules at room temperature and annealing, subsequent impregnation of the formed carrier with an aqueous solution of compounds of platinum and tin, the final air drying the catalyst mass, characterized in that the calcination of the carrier is carried out in the mode of a gradual rise of temperature up to 800-900°C with a speed of 10-200°C./h, then for 5-40 hours at 850-1000°C under constant control of the particle size of the formed crystallites to formation of nanocrystalline particles with an average size of crystallites 22-35 nm at the following content, wt.%:

platinum0,05-2,0
tin0,1-6,0
aluminium spinelrest
platinum0,05-2,0
tin0,1-6,0
aluminium spinelrest

3. The method according to claim 2, characterized in that after drying the obtained catalyst was held by annealing at 400-500°C for 1-5 hours



 

Same patents:

FIELD: chemistry.

SUBSTANCE: invention relates to production of C3-C5 hydrocarbons through dehydrogenation of corresponding paraffin hydrocarbons n reactors with a fluid bed of micro-spherical chromia-alumina catalyst. Method is described for dehydrogenating C3-C5 paraffin hydrocarbons in fluid catalyst bed, containing oxides of chrome, potassium and a promoter, deposited on an alumina support which contains boehmite and up to 10 wt % hydrargillite, which is an aggregate in form of regular, including mimetic, and irregular double aggregates, consisting of hexagonal scaly crystals with size greater than 20 mcm.

EFFECT: increased efficiency of the process of dehydrogenating C3-C5 paraffin hydrocarbons, increased output of C3-C5 olefin hydrocarbons, reduced abrasive action on elements of a two-reactor installation for dehydrogenation when using chromia-alumina catalyst in a fluid bed.

5 cl, 2 tbl, 11 ex, 1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to catalyst production, particularly to production of catalysts for dehydrogenating olefin hydrocarbons. Described is a catalyst based on iron oxide, containing potassium compounds, chrome oxide, molybdenum oxide, ceric oxide and portland cement with the following ratios of components, wt %: potassium compounds (in terms of potassium oxide) 10.0-25.0; chrome oxide 0.5-7.0; molybdenum oxide 0.7-7.0; ceric oxide 1.0-15.0; portland cement 0.5-13.0; the rest is iron oxide.

EFFECT: increased selectivity of catalyst.

3 cl, 1 tbl, 2 dwg, 16 ex

FIELD: chemistry.

SUBSTANCE: proposed method of producing branched olefins involves dehydrogenation of an isoparaffin composition, containing 0.5% or less quaternary aliphatic carbon atoms, on a suitable catalyst. The above mentioned isoparaffin composition contains paraffins with 7 to 35 carbon atoms. These paraffins, or at least part of their molecules, are branched. The average number of branches per paraffin molecule ranges from 0.7 to 2.5, and the branches include methyl and, optionally, ethyl branches. The above mentioned isoparaffin composition is obtained through hydroisomerisation of paraffin, and the above mentioned branched olefins contain 0.5% quaternary carbon atoms or less. The paraffins are produced using Fischer-Tropsch method. The invention also relates to the method of producing a surface active substance from olefins, obtained using the method described above.

EFFECT: improvement of operational characteristics.

5 cl, 4 tbl, 11 ex

FIELD: chemistry.

SUBSTANCE: description is given of a method of obtaining an active phase of a heterogeneous catalyst based on oxides or mixed oxides of transition metals, chosen from a group containing Mo, V, Te, Nb, through successive mixture of aqueous solutions of molybdenum tellurate, vanadium sulphate and niobium oxalate. An aqueous solution of vanadium sulphate is added to the molybdenum tellurate solution first, obtaining a suspension after mixing, which is then added to niobium oxalate. The obtained mixture is further intensively stirred for 10 minutes, kept in an autoclave at 175°C for 50 hours and after filtration and washing, roasted at 600°C in a stream of inert gas. The heterogeneous catalyst for oxidative dehydrogenation of gaseous mixtures of hydrocarbons is a composite material in form of a mechanical mixture of solid dispersion powders obtained from an active phase and an inactive phase with specific surface area of 1-10 m²/g, relative the active dispersion matrix. The method of obtaining the catalyst involves mechanical mixture of powders of active and inactive phases with subsequent pressing, crushing and grading the particles through sieving. Described also is a method of oxidative dehydrogenation of ethane, in which a gas mixture, containing oxygen and ethane in ratio ranging between 1:2.5 and 1:3.5, is fed at pressure of 1 atm and bulk speed of 500-30000 h-1 into a flow reactor with a stationary layer of the heterogeneous catalyst described above, heated to 380-420°C.

EFFECT: increased output of the dehydrogenation process, while maintaining high conversion and selectivity.

11 cl, 1 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to an improved method of producing at least one product of partial oxidation and/or ammoxidation of a hydrocarbon, chosen from a group containing acrolein, acrylic acid, methacrolen, methacrylic acid, acrylonitrile and methacrylonitrile. At least one saturated hydrocarbon is subjected to heterogeneous catalysed dehydrogenation in a gas phase, obtaining a gas mixture, containing at least one partially dehydrogenated hydrocarbon. Components of the gas mixture except saturated hydrocarbon and partially dehydrogenated hydrocarbon are left in the mixture. Alternatively, the extra gas mixture obtained is partially or completely separated, and the gas mixture and/or extra gas mixture are used for obtaining another gas mixture, containing molecular oxygen and/or molecular oxygen and ammonia. This gas mixture is subjected to at least single heterogeneous catalysed partial oxidation and/or ammoxidation of at least one partially dehydrogenated hydrocarbon contained in the gas mixture and/or extra gas mixture. The gas mixture, extra gas mixture and/or the other gas mixture, before at least one partial heterogeneous catalysed oxidation and/or ammoxidation, are subjected to at least a single mechanical separation, aimed at separating particles of solid substance contained in the above mentioned gas mixtures.

EFFECT: reliable and continuous realisation of the process for relatively long periods of time.

6 cl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention refers to method of producing final isoprene-rich and purified C5-fraction from initial C5-fraction "FCC" to be used for selective polymerising isoprene, and method of producing isoprene homopolymer from polymerising medium containing isoprene and, at least, one methyl butene, such as specified isoprene-rich and purified C5-fraction "FCC". Method of producing final fraction from initial C5-fraction involves: catalytic hydrogenation reaction of specified initial C5-fraction with palladium catalyst, leading to intermediate C5-fraction containing n-pentenes in mass fraction less than 0.1 % and methyl butenes, dehydrogenation reaction applied to intermediate C5-fraction containing methyl butenes and made of initial fraction, and purification of final fraction received in such a manner to produce purified final fraction practically recovered from disubstituted alkynes, true alkynes and cyclopentadiene. Mass fraction of methyl butenes in intermediate fraction is less than 30%.

EFFECT: provided efficiency of selective polymerising isoprene ensured by scavenging.

33 cl, 10 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: group of inventions refers to supports (alumina support), to methods for making supports of catalysts activated in aerated layer and chrome-alumina catalyst for dehydrogenation of C3-C5 paraffin hydrocarbons to related olefines being monomers used for manufacturing of chemical rubbers, polymers, blending fuels. There is disclosed alumina support of boehmite morphology, specific surface 80 to 250 m2/g, pore size at least 0.2 cm3/g, microcrystallite size by coherent scattering region 500 to 3000 A. It contains interlayer water in amount corresponding to mole ratio aluminium oxide to water 0.8 to 1.2. There is described method for making support by high-temperature processing of hydrargillite in inert gas and/or ammonia, and/or carbon oxide medium at temperature 100 to 300°C and pressure 0.1 to 150 kgs/cm2 and following drying. Besides, there is disclosed method for making dehydrogenation catalyst of C3-C5 paraffin hydrocarbons by impregnation of support produced as described above with precursor solutions of chrome oxide, potassium oxide and activating agent representing, at least, one oxide chosen from the group: copper oxide, zinc oxide, manganous oxide, tin oxide, boron oxide, zirconium oxide, there after dried and baked at temperature 600 to 900°C.

EFFECT: production of alumina support, development of production methods and methods for making dehydrogenation catalyst on this support of high mechanical strength, low abrasiveness and high activity and selectivity in dehydrogenation of propane, isobutane and isopentane.

7 cl, 2 tbl, 10 ex

FIELD: chemistry.

SUBSTANCE: present invention pertains to obtaining catalysts, particularly catalysts for dehydrogenation of paraffin hydrocarbons into olefins. Description is given of a catalyst for dehydrogenation of C3-C5-paraffin hydrocarbons into olefins, containing, in wt %: chromium (III) oxide - 8.0-23.0; alkali metal oxide - 0.5-3.5; zirconium oxide or a mixture of oxides of zirconium, hafnium and titanium with mass ratio of 1:(0.01-0.3):(0.001-0.05)-0.05-5.0; carrier - rehydrated oxygen-containing aluminium compound with general formula: Al2O3-x(OH)2x·nH2O, where x=0.1-0.5, n=0.7-1.5, with an x-ray amorphous structure, containing 10-50% pseudo boehmite.

EFFECT: increased catalytic activity and stability due to reduced loss during attrition.

5 cl, 2 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: offered invention refers to method of propylene production through propane thermal or oxidising dehydration including supply of propane or mixed propane and air to reactor, interaction of the later with solid catalyst and discharge of dehydration products from reactor, characterised by that propane in thermal dehydration or mixed propane and air in oxidising dehydration is delivered through fixed-bed catalyst layer represented with woven silicate fibre glass carrier with deposited catalytically active component and stabiliser. Carrier is positioned in reactor in the form of layer assembly containing 1 to 10 layers through which propane or mixed propane and air are injected at temperature in reaction zone of within 500 to 600°C and catalyst contact time 0.3 to 3 seconds. Besides offered invention refers to catalyst applied in offered method, and to propane thermal dehydration reactor and to propane oxidising dehydration reactor where catalyst mentioned above is used.

EFFECT: simplified and intensified propane dehydration method, for simplified reactor designs and optimised propane dehydration catalyst.

1 ex, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to group of inventions. Hydrogen is obtained by dehydration of organic substrate on the basis of naphtene hydrocarbons in contact with catalyst, containing platinum on carbon carrier (Pt/C). In carrying out dehydration process, catalyst is heated in electrodynamically coordinated resonance mode of electromagnetic field of SHF resonator, excited by fluctuations of "ТМ"01p type, where p is integer, catalyst Pt/C being placed into reactor made in form of quartz tube, which is placed co-axially with SHF resonator in area of maximal electric field. Device contains system of hydrated organic substrate supply, continuous reactor with Pt/C catalyst in form of granules or powder, SHF resonator, co-axial cable with loop coupler for resonator excitation, fibre-optic sensor, controlling catalyst temperature, amplifier of SHF resonator power, master oscillator, electrically switched over in frequency of electromagnetic SHF fluctuations in band of SHF resonator power amplifier, sensor of control through directional coupler and detector section of SHF resonator power, reflected from inlet into resonator, for automatic resonance SHF resonator tuning, attenuator, electrically controlled for regulating outlet SHF resonator power and supporting optimal catalyst temperature, programme device for controlling process in required modes of obtaining hydrogen.

EFFECT: reduction of energy consumption, increase hydrogen output.

7 cl

FIELD: chemistry.

SUBSTANCE: present invention pertains to perfection of the method of obtaining at least, one product of partial oxidation and/or ammoxidising of propylene, chosen from a group, comprising propylene oxide, acrolein, acrylic acid and acrylonitrile. The starting material is raw propane. a) At the first stage, raw propane, in the presence and/or absence of oxygen, is subjected to homogenous and/or heterogeneous catalysed dehydrogenation and/or oxydehydrogenation. Gas mixture 1, containing propane and propylene is obtained. b) If necessary, a certain quantity of the other components in gas mixture 1, obtained in the first stage, besides propane and propylene, such as hydrogen and carbon monoxide is separated and/or converted to other compounds, such as water and carbon dioxide. From gas mixture 1, gas mixture 1' is obtained, containing propane and propylene, as well as other compounds, besides oxygen, propane and propylene. c) At the third stage, gas mixture 1 and/or gas mixture 1' as a component, containing molecular oxygen, of gas mixture 2, is subjected to heterogeneous catalysed partial gas-phase oxidation and/or propylene, contained in gas mixture 1 and/or gas mixture 1', undergoes partial gas-phase ammoxidising. Content of butane-1 in gas mixture 2 is ≤1 vol.%. The method increases output of desired products and efficiency of the process.

EFFECT: increased output of desired products and efficiency of the process.

72 cl, 10 ex

FIELD: chemistry.

SUBSTANCE: invention pertains to modification of the Houdry method of dehydrogenation of aliphatic hydrocarbons. Description is given of the method of dehydrogenation of aliphatic hydrocarbons, defining the cycle, which includes the following stages: (a) loading the dehydrogenation catalyst into the reactor with obtaining of a catalyst layer, where the layer sets the boundary of the upper section, middle section and the lower section; (b) evacuation of the catalyst layer; (c) restoration of the catalyst layer through hydrogen and evacuation of the catalyst layer; (d) introduction of the aliphatic hydrocarbon into the zone of the catalyst layer in the form of gaseous product with a given speed of flow and in such a way that, the initial product comes into contact first in the upper section and come out after contact in the lower section, after the dehydrogenation of the hydrocarbon; (e) blowing out the vapour and regeneration of the catalyst layer; (f) repetition of stages (b)-(e); duration of stages (b)-(e) is controlled by a device for regulating the sequence of the cycles, differentiated by that, (1) the duration of the cycle increases due to delays, at least, in the form of one preliminarily defined time interval, of at least one stage of the cycle; and (2) hydrogen gas is introduced at percentage molar concentrations of up to 7% H2 in the reaction during stage (d). The method of dehydrogenation of aliphatic hydrocarbons (alternatives) is also given.

EFFECT: increased lifetime of the catalyst; increase in its activity and selectiveness; maintenance of the output of the desired olefins.

17 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: catalyst for dehydration of alcylaromatic hydrocarbons containing oxides of iron, alkaline-earth metals, cerium (4), molybdenum, titanium and/or vanadium and potassium is described. The diffraction pattern of said catalyst contains reflexes of potassium polyferrite and hematite phase related to iron (3) oxide in α-form. The relative intensities of said reflexes are (1÷40) and 100% respectively. Catalyst component ratio may be as follows: potassium oxide 5-30 Wt%; oxides of alkaline-earth metals 1-10 Wt%; cerium (4) oxide 5÷20 Wt%; molybdenum oxide 0.2-5 Wt%; titanium and/or vanadium oxide 0.2-5 Wt%; iron (3) oxide - the rest. Additionally catalyst can contain up to 30 Wt% of rubidium oxide and/or cesium oxide. The catalyst is prepared by calcinating at temperatures 500-750°C during 1-3 hr and 800-900°C during 0.5-1.5 hr. Bulk density of catalyst is in the range 0.95-1.5g/sm2.

EFFECT: development of catalyst providing high conversion and selectivity in relation of end products in the process of alcylaromatic hydrocarbons dehydration; increasing of catalyst service cycle.

5 cl, 1 tbl, 15 ex

FIELD: hydrogenation and dehydrogenation catalysts.

SUBSTANCE: catalyst according to invention is composed of, wt %: potassium and/or lithium, and/or rubidium, and/or cesium compound 5-30, magnesium oxide 0.5-10, cerium(IV) oxide 5-20, calcium carbonate 1-10, molybdenum oxide 0.5-5, ferric oxide - the balance. Catalyst is characterized by loose density at least 1.0 g/cc but not higher than 2.00 g/cc and apparent density at least 2.0 g/cc but not higher than 3.5 g/cc. Starting ferric oxide has loose density 1.0-1.5 g/cc.

EFFECT: increased selectivity and strength of catalyst.

1 tbl, 13 ex

FIELD: hydrogenation-dehydrogenation catalysts.

SUBSTANCE: invention relates to production of alkylaromatic hydrocarbon dehydrogenation catalysts and can be employed in chemical and petrochemical industries. Catalyst according to invention comprising molybdenum oxide MoO2, ferrous oxide F2O3, cerium dioxide CeO2, and iron, potassium, calcium , and magnesium compounds is characterized by containing solid solution of potassium ferrites and, additionally, cesium and/or rubidium ferrites MFeO2 and M2Fe10O16, where M=K+Contains and/or Rb, and also ferrite Ca2(MgZn)1Fe2O3 Catalyst may be granulated in the form of trefoil with holes in each foil, which are shifted toward the center of granule, or it may be in the form of circle with three, four, or five internal spokes. Catalyst preparation process and a process of dehydrogenation of alkylaromatic hydrocarbons in presence of indicated catalyst are also described.

EFFECT: enabled preparation of strong catalyst showing high activity and selectivity, and ensuring reduced pressure in reactor owing to lowered hydraulic resistance.

11 cl, 4 tbl, 10 ex

FIELD: industrial organic synthesis.

SUBSTANCE: in two-stage isoprene production process via dehydration of isopentane, contact gas produced in each stage is condensed and non-condensed hydrocarbons are absorbed and then desorbed. Hydrocarbon condensate is separated by rectification to give low-boiling hydrocarbon distillate fraction and bottom product. The latter is separated with the aid of extractive rectification to give isopentane and isoamylene fractions after the first dehydration stage and isoprene and isoamylene fractions after the second dehydration stage. Non-condensed low-boiling hydrocarbon vapors recovered after rectification are combined with non-condensed hydrocarbons from the first dehydration stage, preliminarily compressed, separated, and subjected to absorption.

EFFECT: maximized utilization of C5-hydrocarbons leading to reduced consumption of isopentane.

2 dwg, 4 tbl

FIELD: petrochemical process catalysts.

SUBSTANCE: catalyst contains, wt %: potassium oxide and/or rubidium oxide, cesium oxide 10-40, magnesium oxide 2-10, cerium(IV) oxide 2-20, sulfur 0.2-5, and ferric oxide the rest.

EFFECT: increased selectivity and mechanical strength of catalyst.

1 tbl, 17 ex

FIELD: petroleum chemistry.

SUBSTANCE: olefin hydrocarbons are obtained by dehydration of paraffin hydrocarbons in presence of catalyst. Claimed method includes: preparation of mixture from direct and recycled paraffin hydrocarbon streams; vaporization; vapor heating; and overheating in oven before feeding into reactor; cooling of contact gas in disposal boiler and scrubber with water by using two circulating contours with different water temperature and air cooling of water; followed by tree-step contact gas compression with intermediate condensation; condensation; absorption of uncondensed hydrocarbons; and recovery of paraffin-olefin cut by fractionation of obtained hydrocarbon condensate. Temperature of contact gas fed into compression is stabilized on predetermined level by alteration of contact gas temperature on wet scrubber input and temperature of circulating water fed into top of wet scrubber, while said circulating water is cooled in one or two steps according to contact gas temperature on wet scrubber input; and circulating water temperature is changed either using or without air cooling.

EFFECT: decreased losses of raw material and catalyst, increased utilization coefficient of contact gas heat, and improved process stabilization.

2 cl, 1 dwg, 10 ex

The invention relates to the field of petrochemicals

The invention relates to a chemical reactor and method using a chemical reactor, which is used with the installation of the heat transfer walls, inside the reactor, which will maintain the temperature inside the reactor at the desired intervals during the reaction

FIELD: physics.

SUBSTANCE: invention relates to micro- and nanoelectronics, and specifically to memory devices made using micro- and nano-electronic methods. The memory cell includes two electrodes with a dielectric layer placed between them. The dielectric layer has defects which provide electrical conduction by tunneling carriers in the defects, and contains semiconductor material impurities near one of the electrodes which provide for acquisition, storage and removal of electric charge, which blocks current from flowing in the defects of the dielectric layer.

EFFECT: design of a two-electrode nonvolatile reprogrammable memory cell with reproducible parametres, using the effect of electrical charge storage.

6 dwg

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