Isoprene production process

FIELD: industrial organic synthesis and petrochemistry.

SUBSTANCE: isoamylenes are subjected to dehydrogenation in presence of overheated water steam and catalyst containing, wt %: potassium oxide and/or lithium oxide, and/or rubidium oxide, and/or cesium oxide, 10-40; cerium(IV) oxide 2-20; magnesium oxide 2-10; calcium carbonate 2-10; sulfur 0.2-5; and ferric oxide - the rest.

EFFECT: increased isoamylene dehydrogenation degree due to increased catalyst selectivity with regard to isoprene and prolonged service time of catalyst.

2 tbl, 22 ex

 

The invention relates to the chemical and petrochemical industry, namely the production of diene hydrocarbons, in particular the production of isoprene, which is a monomer for the production of synthetic rubbers.

A known method of producing isoprene by degidrirovanie of isoamylenes upon dilution with water vapor at a stationary catalyst bed consisting of 10-20 wt.% of potassium oxide, 0.1-5 wt.% oxide of rubidium or cesium oxide, 0.5-1.2 wt.% silicon oxide, 2-5 wt.% magnesium oxide and/or calcium oxide, 0.05-2 wt.% copper oxide and iron oxide - rest (RF Patent No. 2116830, IPC 01 J 23/86, publ. 1998.08.10).

However, the retrieval of isoprene in this way is characterized by a lack of selectivity due to high kekirawa activity generated in the catalyst orthoferrite rubidium or cesium, and the high rate of coke formation on the surface of the formed catalyst magnetite, metasilicate iron and solid solutions of iron in the crystal lattice of chromite.

Closest to the present invention is a method of producing isoprene by dehydrogenation of isoamylenes when diluted raw water vapor on samoreguliruetsja the catalyst having the following composition: 3.5-6 wt.% chromium oxide (3), 19-25 wt.% potassium carbonate, 2-2 .6 wt.% silicate of potassium, 2.4-3 wt.% zirconium oxide (4), 0.05-0.6 wt.% magnesium oxide, 0.005-0.05 the AC.% sulfur, iron oxide (3) - the rest (AS the USSRâ„–1415684, IPC C 07 C 11/18, publ. 1999.10.12).

The process of production of isoprene in this way is characterized by insufficient meregenerasikan cycle due to the high speed supervivencia the catalyst surface due to the metastability of the active phase of the catalyst, which during operation and regeneration of transformed with the formation of magnetite.

The objective of the invention is to develop a method of producing isoprene, allowing a deepening of the process of dehydrogenation of isoamylenes by increasing selectivity for isoprene and increase mezhregionalnogo cycle of operation of the catalyst (the life of the catalyst).

The task is solved by providing a method of producing isoprene by dehydrogenation of isoamylene in the presence of superheated water vapor and catalyst containing the oxides of potassium and/or lithium oxide and/or oxide of rubidium and/or cesium oxide, cerium oxide, magnesium oxide, calcium carbonate, sulfur, and iron oxide in the following ratio, wt.%:

The oxide of potassium and/or lithium oxide and/or oxide of rubidium

and/or cesium oxide 10-40

The cerium oxide (4) 2-20

Magnesium oxide 2-10

Calcium carbonate 2-10

Sulfur 0.2-5

Iron oxide (3) - rest

When comparing essential features of the invention with those of the prototype was is revealed, they are new and are not described in the prototype, so we can make conclusion on the conformity of the proposed technical solution the criterion of "novelty".

The introduction of new distinctive characteristics in combination with the achieved result indicates an inventive step of the invention.

The present invention meets the criterion of "industrial applicability"because it can be used in industry, as evidenced by examples of specific embodiment of the invention.

The catalyst is prepared by mixing iron oxide, magnesium oxide, potassium oxide and/or lithium oxide and/or oxide of rubidium and/or cesium oxide or compounds listed metals, decompose with the formation of oxides of these elements, as well as calcium carbonate. In the resulting catalyst mass is added the compound of cerium, subsequently giving the cerium oxide and a sulfur containing compound, decomposing with the formation of elemental sulfur. The resulting catalyst mass is formed by extrusion, dried and calcined. The finished granules of the catalyst are in the form of extrudates with a diameter of 2.5-3.0 mm, a length of 5-10 mm as an indicator of the lifetime of the catalyst, take the time during which there is a decrease in activity (missed isoamylene) by 1%. Data on mainegeneral the th cycle of the catalysts are shown in table 2.

As sources of formation of iron oxide can be used iron hydroxide goethite, iron oxides hematite, maghemite, magnetite, and mixtures thereof, iron carbonate, iron oxalate, iron nitrate, nitrite, iron, iron chloride, iron bromide, fluoride, iron, iron sulfate, iron sulfide, iron sulfite, chlorate iron, iron thiosulfate, iron acetate or mixtures of these salts, as well as salesonline alum, Gelezinkeliai alum.

As a source of potassium oxide can be applied potassium carbonate, potassium hydroxide, potassium nitrate, potassium nitrite, potassium sulfate, potassium permanganate, potassium oxalate, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, persulfate potassium chlorate potassium or mixtures thereof.

As a source of lithium oxide can be used lithium carbonate, lithium hydroxide, lithium nitrate, lithium nitrite, lithium sulfate, lithium oxalate, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, persulfate lithium chlorate lithium or mixtures thereof.

As the source of oxide of rubidium can be used rubidium carbonate, rubidium hydroxide, rubidium nitrate, nitrite, rubidium, rubidium sulfate, oxalate rubidium, rubidium fluoride, rubidium chloride, rubidium bromide, rubidium iodide, persulfate rubidium, rubidium chlorate, or a mixture thereof.

As a source of cesium oxide can be used cesium carbonate, cesium hydroxide, nitrate is Asia, nitrite, cesium, cesium sulfate, cesium oxalate, cesium fluoride, cesium chloride, cesium bromide, cesium iodide, persulfate cesium, cesium chlorate, or a mixture thereof.

As a source of magnesium oxide can be used magnesium oxide, magnesium hydroxide, magnesium carbonate, magnesium sulfate, magnesium acetate, or a mixture thereof.

As a source of cerium oxide can be used cerium oxide (3), cerium oxide (4), cerium nitrate, cerium hydroxide, cerium carbonate, oxalate of cerium or mixtures thereof.

As a source of sulfur can be applied magnesium sulfate, potassium sulfate, calcium sulfate, iron sulfate (2) or ferrous sulfate (3), ammonium sulfate, sulfuric acid, hydrogen sulfide, elemental sulfur, organic sulfur-containing compounds.

Example 1

The reaction of dehydrogenation of isoamylenes carried out in a laboratory reactor at 40 cm3granules of catalyst size 2×3 mm at 600, 610 and 615°C, the dilution of the raw water vapor in a molar ratio of 1:20 and the space velocity of the hydrocarbon feedstock 1 h-1. After 20 h dehydrogenation select and analyze time sample gas contact. Used catalyst has the following composition:

To2O - 15%, Fe2About3- 66.5%SEO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment (the catalyst activity and selectivity to isoprene) and meregenerasikan CEC is the work of the catalyst are listed in tables 1 and 2.

Example 2

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

K2O - 15%, Fe2About3- 66.6%, CeO2- 6%, caso3- 10%, MgO - 2%, S - 0.4%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 3

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2O - 14%, Fe2About3- 65.5%SEO2- 6%, caso3- 10%, MgO 2%, and the S - 2.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 4

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2About - 13.5%, Fe2O3- 64%, CeO2- 5.5%, caso3- 10%, MgO - 2%. S - 5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 5

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2O - 15%, Fe2About3- 66.6%, CeO2- 6%, caso3- 10%, MgO - 2%, S - 0.4%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables is x 1 and 2.

Example 6

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2About 25%, and Fe2About3- 56%SEO2- 5.5%, caso3- 10%, MgO - 3%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation is shown in tables 1 and 2.

Example 7

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2O - 12%, Fe2About3- 68%SEO2- 12.5%, caso3- 4%, MgO - 3%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 8

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2O - 12%, Fe2About3- 68%SEO2- 5%, caso3- 5.5%, MgO - 9%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 9

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2O - 9%, Cs2O - 3%, Fe2About3- 68%SEO2- 5%, caso3- 5.5%, MgO - 9%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst described in that the faces 1 and 2.

Example 10

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

Li2O - 12%, Fe2About3- 69.5%SEO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 11

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

Rb2O - 10%, Fe2About3- 70.5%, CeO2- 7%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 12

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

Cs2O - 15%, Fe2About3- 66.5%SEO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 13

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2About 9 percent, Li2O - 1%, Cs2O - 2%, Rb2O - 3%, Fe2About3- 66.5%, CeO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan qi is Lou operation of the catalyst are listed in tables 1 and 2.

Example 14

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

Li2O - 15%, Cs2O - 2%, Rb2O - 3%, Fe2About3- 61.5%SEO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 15

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

Cs2O - 12%, Rb20 - 3%, Fe2O3- 66.5%, CeO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 16

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2O - 10%, Cs2O - 2%, Rb2O - 3%, Fe2About3- 61.5%SEO2- 11%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 17

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2O - 10%, Cs2O - 4%Li2O - 1%, Fe2About3- 61.5%, CeO2- 11%, caso3- 10%, MgO - 2%, S - 0.5%.

<> The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 18

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

K2O - 10%Li2O - 2%, Rb2O - 3%, Fe2O3- 61.5%, CeO2- 11%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 19

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

Li2O - 10%, Cs2O - 2%, Fe2About3- 69.5%, CeO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 20

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

Li2O - 10%, Rb2O - 2%, Fe2About3- 69.5%, CeO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 21

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

Li2O - 10%, K2 O - 2%, Fe2About3- 69.5%, CeO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

Example 22

The reaction of dehydrogenation of isoamylenes carried out as described in example 1, using a catalyst of the following composition:

To2O - 15%, Rb2O - 2%, Fe2About3- 64.5%SEO2- 6%, caso3- 10%, MgO - 2%, S - 0.5%.

The results of the experiment and data meregenerasikan cycle of operation of the catalyst are listed in tables 1 and 2.

As seen from the above examples, the proposed method of producing isoprene can improve the selectivity of the dehydrogenation of isoamylenes, as well as to increase the activity and the period between regenerations operation of the catalyst.

Increased activity and selectivity of the catalyst may be due to partial deactivation of the most strong Lewis sites of acid centers - cations of iron, Fe3+localized on the surface of the crystallites of iron oxide, which has a higher kekirawa activity.

Table 1
# exampleThe reaction temperature dehydrogenation, °The activity of the catalyst on the missed isoamylene, %The selectivity of the process is sa for isoprene, %
160041.91of 92.7
61051.0887.07
61553.7188.25
260042.092.0
61551.289.0
360028.085.0
61031.487.3
61536.086.0
460026.076.0
60530.682.4
560042.092.0
660045.381,9
760038.089.0
860038.590.0
960039.287.1
106003890
1160040.593
1260045.585
1360040.390.1
146003.2 89.9
1560043.789
1660039.990
1760042.290.5
186003990
1960049.887
2060042,689.1
216004193.05
226004493

71
Table 2
# exampleTime to reduce the activity of the catalyst at 1%an hour.Period between regenerations work catalyst, h
1150850
2137850
392730
458560
5155850
660560
7102780
8101780
9113785
10600
1174600
1265560
13103780
1499780
1575600
16140850
17115785
18115785
1962500
2060500
21150850
22135850
(T=600°C; volumetric ratio of raw materials:steam=1:20; υabout=1 h-1)

A method of producing isoprene by dehydrogenation of isoamylene in the presence of superheated water vapor and catalyst containing the oxides of potassium and/or lithium oxide and/or oxide of rubidium and/or cesium oxide, cerium oxide, magnesium oxide, calcium carbonate, sulfur, and iron oxide in the following ratio, wt.%:

The oxide of potassium and/or lithium oxide, and/or
the oxide of rubidium and/or cesium oxide10-40
The cerium oxide (4) 2-20
Magnesium oxide2-10
Calcium carbonate2-10
Sulfur0,2-5
Iron oxide (3)Rest



 

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The invention relates to catalytic chemistry, in particular to catalysts for the synthesis of olefins from monohalogenated paraffins, and may find application in the disposal of chlorinated organic wastes, as well as in the production of synthetic rubber

The invention relates to the preparation of heterogeneous catalysts used in the processes of oxidative chlorination of hydrocarbons

The invention relates to the field of oil refining and petrochemical industries, in particular, to a method of obtaining a mixture of gaseous hydrocarbons, dominated in its composition olefinic hydrocarbon, C2-C4that can be used in the process of obtaining the appropriate polymers and other petrochemical products

The invention relates to catalytic chemistry, in particular to methods for khrommagnievogo catalyst gas-phase fluorination of kalogeropoulou, including for the synthesis of halocarbons

FIELD: inorganic synthesis catalysts.

SUBSTANCE: passivation of ammonia synthesis catalyst is accomplished via consecutively treating reduced iron catalyst with oxidant at elevated temperatures and process flow rates. Treatment of catalyst with oxidant is commenced with water steam or steam/nitrogen mixture at 150-300°C while further elevating temperature by 50-200°C, after which temperature is lowered to 150-300°C, at which temperature water steam or steam/nitrogen mixture is supplemented by air and treatment of catalyst is continued with resulting mixture while elevating temperature by 50-200°C followed by reduction of catalyst temperature in this mixture to 150-300°C and cooling of catalyst with nitrogen/oxygen mixture at initial ratio not higher than 1:0.1 to temperature 30°C and lower until nitrogen/oxygen mixture gradually achieves pure air composition.

EFFECT: prevented self-inflammation of ammonia synthesis catalyst when being discharged from synthesis towers due to more full oxidation.

6 cl, 1 tbl, 5 ex

FIELD: petrochemical process catalysts.

SUBSTANCE: invention is dealing with catalyst applicable in saturated hydrocarbon ammoxidation process resulting in corresponding unsaturated nitrile. Catalyst composition of invention comprises complex of catalytic oxides of iron, bismuth, molybdenum, cobalt, cerium, antimony, at least one of nickel and magnesium, and at least one of lithium, sodium, potassium, rubidium, and thallium and is described by following empirical formula: AaBbCcFedBieCofCegSbhMomOx, wherein A represents at least one of Cr, P, Sn, Te, B, Ge, Zn, In, Mn, Ca, W, and mixtures thereof; B represents at least one of Li, Na, K, Rb, Cs, Ti, and mixtures thereof; C represents at least one of Ni, Mg, and mixtures thereof; a varies from 0 to 4.0, b from 0.01 to 1.5, c from 1.0 to 10.0, d from 0.1 to 5.0, e from 0.1 to 2.0, f from 0.1 to 10.0, g from 0.1 to 2.0, h from 0.1 to 2.0, m from 12.0 to 18.0, and m is a number determined by requirements of valences of other elements present. Ammoxidation processes for propylene, ethylene, or their mixtures to produce, respectively, acrylonitrile, methacrylonitrile, or their mixtures in presence of above-defined catalytic composition is likewise described.

EFFECT: increased olefin conversion.

9 cl, 1 tbl

FIELD: nitric acid production.

SUBSTANCE: invention relates to decomposition of N2O from nitric acid production emission gases. N2O is decomposed by contacting N2O-containing emission gas escaping absorption column with catalyst containing at least one cobalt oxide compound and at least one magnesium oxide compound under conditions favoring formation of N2O into nitrogen and oxygen gases, content of said cobalt oxide compounds ranging between 0.1 and 50% and that of magnesium oxide compounds between 50 and 99.9% based on the total weight of catalyst. At least 30% of cobalt in catalyst are in trivalent state. Preparation of catalyst envisages dry mixing of cobalt oxide and magnesium oxide compounds or corresponding precursors followed by compaction of the mixture under anhydrous conditions such that resulting catalyst has desired volume density.

EFFECT: enabled high degree of N2O decomposition at low temperatures and without disadvantages for nitric acid production process.

20 cl, 2 dwg

FIELD: catalyst manufacture technology.

SUBSTANCE: invention relates to carbon monoxide-water steam conversion to form nitrogen-hydrogen mixture that can be used in ammonia synthesis. Preparation of catalyst comprises precipitation of iron hydroxide from iron nitrate solution with ammonia-containing precipitator, washing of iron hydroxide to remove nitrate ions, mixing with copper compound, granulation, and drying and calcination of granules. Invention is characterized by that iron hydroxide is mixed with copper and calcium oxides at molar ratio Fe2O3/CuO/CaO = 1:(0.03-0.2):(1.0-2.0), after which mechanical activation is performed. Resulting catalyst is 1.8-2.0-fold stronger and by 11.0-15.4% more active than prototype catalyst.

EFFECT: increased strength and catalytic activity.

1 tbl, 3 ex

FIELD: chemical industry.

SUBSTANCE: the invention is pertinent to the field of chemical industry, in particular to production of a catalysts and processes of oxidation of ammonia in production of a weak nitric acid. The invention offers an ammonia conversion catalyst on the basis of the mixture of oxides of unitized structure and a method oxidation of ammonia in production of weak nitric acid. The catalyst represents a mixture of oxides of the over-all formula (AxByO3Z)k (MmOn)f, (NwPgvOv)r where: A - cation of Ca, Sr, Ba, Mg, Be, Ln or their mixtures; B - cations of Mn, Fe, Ni, Co, Cr, Cu, V, A1 or their mixtures; x=0-2, y=1-2, z=0.8-l.7; M - A1, Si, Zr, Cr, Ln, Mn, Fe, Co, Cu, V, Ca, Sr, Ba, Mg, Be or their mixtures; m=l-3, n=l-2; N - Ti, Al, Si, Zr, Ca, Mg, Ln, W, Mo or their mixtures, P - phosphorus, O - oxygen; w=0-2, g=0-2, v=l-3; k, f and r - mass %, at a ratio (k+f)/r=0-l, f/r=0-l, k/f = 0-100. The catalyst is intended for use in a composition of a two-stage catalytic system generated by different methods, also in a set with the trapping platinoid screens and-or inert nozzles. The technical result ensures activity, selectivity and stability of the catalyst to thermocycles at its use in two-stage catalytic system with a decreased loading of platinoid screens.

EFFECT: the invention ensures high activity, selectivity and stability of the catalyst to thermocycles at its use in two-stage catalytic system with a decreased loading of platinoid screens.

8 cl, 1 tbl, 5 ex

The invention relates to a catalyst and process for the oxidation of ammonia in the production of weak nitric acid
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