RU2285560C1 - Catalyzer for dehydrogenation of the alkyl-aromatic hydrocarbons - Google Patents

Abstract

FIELD: chemical industry; catalyzers for dehydrogenation of the alkyl-aromatic hydrocarbons.

SUBSTANCE: the invention presents the catalyzer used for dehydrogenation the alkyl-aromatic hydrocarbons of the following composition (in mass%): potassium compounds (in terms of potassium oxide) - 8.0-25.0; magnesium compounds and-or calcium compounds (in terms of magnesium oxide and-or calcium oxide) - 0.2-7.0; molybdenum oxide - 0.7-7.0; cerium oxide - 1.0-15.0; Portland cement - 0.5-12.0; lanthanum oxide and-or neodymium oxide - 0.01-7.0; iron oxide - the rest. The technical result of the invention is the increase of activity, selectivity of the catalyzer, as well as the thermal stability, which increases the catalyzer service life.

EFFECT: the invention ensures the increase of activity, selectivity, thermal stability and the service life of the catalyzer.

4 cl, 20 ex, 2 tbl, 2 dwg

Description

The invention relates to the production of catalysts, and in particular to the production of catalysts for the dehydrogenation of alkyl aromatic hydrocarbons.

A known catalyst for the dehydrogenation of ethylbenzene of the following composition, wt.%: Zirconium dioxide 0.5-2.5; potassium carbonate 13.0-25.0; potassium silicate 0.5-3.0; rubidium or cesium oxide 0.5-5.0; molybdenum oxide 0.5-1.5; cerium oxide 2.0-6.0; iron oxide - the rest (RF patent No. 1267657, 1984).

Closest to the proposed is a catalyst for the dehydrogenation of alkylaromatic hydrocarbons, containing, wt.%: Fe ₂ O ₃ - 45-90; K ₂ O - 5-40; MgO - 4-30; CeO ₂ 0-10; MoO ₃ - 0-10; WO ₃ - 0-10; CaO - 0-15, pore-forming, binding and forming agent (Application of Germany No. 3442636, 1986).

The disadvantages of these catalysts are their relatively low activity, selectivity and service life.

The problem solved by the present invention is to increase the activity, selectivity of the catalyst, as well as thermal stability, which, in turn, will increase the service life.

A catalyst is proposed for the dehydrogenation of alkyl aromatic hydrocarbons of the following composition, wt.%: Potassium compounds (in terms of potassium oxide) 8.0-25.0; magnesium compounds and / or calcium compounds (in terms of magnesium oxide and / or calcium oxide) 0.2-7.0; cerium oxide 1.0-15.0; molybdenum oxide 0.7-7.0; Portland cement 0.5-12.0; additionally, lanthanum oxide and / or neodymium oxide 0.01-7.0 and iron oxide - the rest.

As a potassium compound, the catalyst may contain potassium polyferrites of the composition K ₂ O • 5Fe ₂ O ₃ and / or K ₂ O • 11Fe ₂ O ₃ .

Additionally, the catalyst may contain zirconium oxide, tin oxide and tungsten oxide in an amount of 0.01-1.0 wt.% Each.

Preferably, the catalyst is molded in the form of three to five petal granules (FIG. 1 and FIG. 2).

The difference between the proposed catalyst from the prototype is the additional content of lanthanum oxide and / or neodymium oxide and a new ratio of components (qualitative and quantitative).

Additional differences are:

- the content in the proposed catalyst as a compound of potassium potassium polyferrites;

- the content of zirconium oxide, tin oxide and tungsten oxide in an amount of 0.01-1.0 wt.% each;

- molding the catalyst in the form of three to five petal granules.

In the proposed catalyst, a new combination of all components can significantly increase the activity, selectivity and thermal stability of the catalyst. The shape of the catalyst improves its performance by reducing the hydraulic resistance of the catalyst layer in an industrial reactor.

The proposed catalyst is prepared by mixing in a predetermined ratio of carefully ground oxides or decomposed to oxides compounds of iron, molybdenum, cerium, lanthanum and / or neodymium, compounds of magnesium and / or calcium. The alkaline promoter is introduced in the form of an aqueous solution of potassium compounds, as well as in the form of potassium polyferrites.

Potassium polyferrites are prepared by mixing in a predetermined ratio of iron oxide and an aqueous solution of potassium carbonate or potassium hydroxide for 1.0-3.0 hours. The resulting paste is formed by extrusion into cylindrical granules with a diameter of 2.0-6.0 mm, dried at a temperature of 100-150 ° C and calcined at a temperature of 650-1000 ° C. Then grind and injected into the catalyst. It is also possible to obtain potassium polyferrites by calcining the catalyst itself at a temperature of 800-1100 ° C.

Portland cement is introduced at the stage of mixing the dry catalyst components.

The catalyst mass is stirred for 0.5-5.0 hours until a homogeneous mass is obtained, then formed by extrusion into cylindrical or three-five-petal granules, dried at 100-200 ° C and calcined at 550-850 ° C.

The invention is illustrated by the following examples.

Example 1

The estimated amount of dry catalyst components: iron oxide (α-Fe ₂ About ₃ ), molybdenum oxide, cerium oxide, Portland cement, magnesium oxide, lanthanum oxide are mixed for 1 hour. An aqueous solution of potassium carbonate is added. The catalyst mass is stirred for 1.5 hours to obtain a homogeneous mass, then formed by extrusion into cylindrical granules with a diameter of 3.0 mm, dried at a temperature of 120 ° C and calcined at 650 ° C for 3 hours.

Get the catalyst composition, wt.%: Fe ₂ About ₃ - 65,99; K ₂ O - 16.0; MgO - 5.0; MoO ₃ - 1.0; CeO ₂ - 4.0; Portland cement - 8.0; La ₂ O ₃ - 0.01.

Tests of the catalyst are carried out in the reaction of dehydrogenation of ethylbenzene to styrene at a temperature of 620 ± 20 ° C, a feed rate of liquid ethylbenzene of 0.5-1.5 l / l of catalyst per hour and mass dilution of the feed with water vapor 1: 2-3. The test data of the catalyst are shown in table 1.

Example 2

The catalyst is prepared analogously to example 1, but instead of lanthanum oxide, the calculated amount of neodymium oxide is used and the ratio of components is changed.

Get the catalyst composition, wt.%: Fe ₂ About ₃ - 66.09; K ₂ O - 8.0; MgO - 7.0; MoO ₃ - 5.4; CeO ₂ - 7.0; Portland cement - 6.5; Nd ₂ O ₃ - 0.01.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 3

The catalyst is prepared analogously to example 1, but additionally use the estimated amount of neodymium oxide and change the ratio of components.

Get the catalyst composition, wt.%: Fe ₂ About ₃ - 72.3; K ₂ O - 14.0; MgO - 0.2; MoO ₃ - 5.0; CeO ₂ - 1.0; Portland cement - 0.5; La ₂ O ₃ - 6.0; Nd ₂ O ₃ - 1.0.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 4

The catalyst is prepared analogously to example 1, but instead of magnesium oxide, the calculated amount of calcium oxide is used and the ratio of components is changed.

The composition of the obtained catalyst is as follows, wt.%: Fe ₂ O ₃ - 62.5; K ₂ O - 24.0; CaO - 1.0; MoO ₃ - 0.7; CeO ₂ - 4.3; Portland cement - 6.0; La ₂ O ₃ - 1.5.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 5

The catalyst is prepared analogously to example 1, but calcium oxide is added and the ratio of components is changed.

The composition of the obtained catalyst is as follows, wt.%: Fe ₂ About ₃ - 58.9; K ₂ O - 10.0; MgO - 1.0; CaO-1.0; MoO ₃ - 2.0; CeO ₂ - 15.0; Portland cement - 12.0; La ₂ O ₃ - 0.1.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 6

The catalyst is prepared analogously to example 1, but the ratio of components is changed.

The composition of the obtained catalyst is as follows, wt.%: Fe ₂ About ₃ - 66.0; K ₂ O - 14.0; MgO - 2.0; MoO ₃ - 6.0; CeO ₂ - 2.0; Portland cement - 3.0; La ₂ O ₃ - 7.0.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 7

The catalyst is prepared analogously to example 3, but the ratio of components is changed.

The composition of the obtained catalyst is as follows, wt.%: Fe ₂ About ₃ - 69.0; CaO - 12.5; MgO - 3.0; MoO ₃ - 2.2; CeO ₂ - 5.5; Portland cement - 7.0; La ₂ O ₃ - 0.70; Nd ₂ O ₃ - 0.10.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 8

The catalyst is prepared analogously to example 1, but as a potassium compound, pre-prepared potassium polyferrite is also used.

Get the catalyst composition, wt.%: Fe ₂ About ₃ - 65,99; K ₂ O - 14.5; potassium polyferrite (calculated as K ₂ O) - 1.5; MgO - 5.0; MoO ₃ - 1.0; CeO ₂ - 4.0; Portland cement - 8.0; La ₂ O ₃ - 0.01.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 9

The catalyst is prepared analogously to example 1, but at the stage of mixing the dry components, the calculated amount of zirconium oxide, tin oxide and tungsten oxide is additionally introduced.

The composition of the obtained catalyst is as follows, wt.%: Fe ₂ About ₃ - 66.5; K ₂ O - 16.0; MgO - 2.0; MoO ₃ - 1.0; CeO ₂ - 4.0; Portland cement - 6.0; La ₂ O ₃ - 1.5; ZrO ₂ - 1.0; SnO ₂ - 1.0; WO ₃ - 1.0.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 10

The catalyst is prepared analogously to example 9, but the ratio of components is changed. The composition of the obtained catalyst is as follows, wt.%: Fe ₂ About ₃ - 69.47; K ₂ O - 16.0; MgO - 2.0; MoO ₃ - 1.0; CeO ₂ - 4.0; Portland cement - 6.0; La ₂ O ₃ - 1.5; ZrO ₂ - 0.01; SnO ₂ - 0.01; WO ₃ - 0.01.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 11

The catalyst is prepared analogously to example 9, but the ratio of components is changed.

The composition of the obtained catalyst is as follows, wt.%: Fe ₂ O ₅ - 69.48; K ₂ O - 12.0; MgO -2.5; MoO ₃ - 2.0; CeO ₂ - 5.0; Portland cement - 6.0; La ₂ O ₃ - 1.5; ZrO ₂ - 1.0; SnO ₂ - 0.5; WO ₃ - 0.02.

The catalyst was tested analogously to example 1. The test data for the catalyst are shown in table 1.

Example 12

The catalyst is prepared analogously to example 1, but formed into three-petal granules with d ₁ = 3.0 mm; d ₂ = 1.9 mm (Fig. 1). The catalyst was tested in the dehydrogenation reaction of ethylbenzene under the conditions described in example 1. The test data for the catalyst are shown in table 1.

Example 13

The catalyst is prepared analogously to example 1, but is formed into five-petal granules d ₁ = 3.1 mm; d ₂ = 1.6 mm (figure 2). The catalyst was tested in the dehydrogenation reaction of ethylbenzene under the conditions described in example 1. The test data for the catalyst are shown in table 1.

Example 14

The catalyst is prepared analogously to example 4, but it is tested in the dehydrogenation reaction of isopropylbenzene to alpha-methylstyrene at a temperature of 560 ± 20 ° C, the feed rate of liquid isopropylbenzene is 0.5-1.5 l / l of catalyst per hour and mass dilution of the feed with 1: 3 steam . Test data are shown in table 1.

Example 15

The catalyst is prepared analogously to example 11, but is tested in the dehydrogenation reaction of isopropylbenzene to alpha-methylstyrene under the conditions described in example 14. The data on the catalyst tests are shown in table 1.

Example 16

The catalyst is prepared analogously to example 12, but is tested in the dehydrogenation reaction of isopropylbenzene to alpha-methylstyrene under the conditions described in example 14. The data on the catalyst tests are shown in table 1.

Example 17

The catalyst is prepared analogously to example 4.

To assess the life of the catalyst, an artificial aging method is used, consisting in the fact that the catalyst sample is subjected to heat treatment at a temperature of 800 ° C for 3 hours. The catalyst sample is tested both before and after heat treatment in the ethylbenzene dehydrogenation reaction under the conditions described in example 1.

The test data are shown in table 2.

Example 18

The catalyst is prepared analogously to example 8.

The catalyst is subjected to artificial aging and experience analogously to example 17.

The test data for the catalyst are shown in table 2.

Example 19

The catalyst is prepared analogously to example 10.

The catalyst is subjected to artificial aging and experience analogously to example 17.

The test data for the catalyst are shown in table 2.

Example 20

For comparison, a catalyst sample is prepared according to the prototype: the estimated amount of dry catalyst components: iron oxide (α-Fe ₂ O ₃ ), molybdenum oxide, cerium oxide, magnesium oxide, tungsten oxide, Portland cement are mixed for 1 hour. An aqueous solution of potassium carbonate is added. The catalyst mass is stirred for 1.5 hours to obtain a homogeneous mass, then formed by extrusion into cylindrical granules with a diameter of 3.0 mm, dried at a temperature of 120 ° C and calcined at 650 ° C for 3 hours.

Get the catalyst composition, wt.%: Fe ₂ About ₃ - 64.5; K ₂ O - 12.0; MgO - 6.0; CeO ₂ - 6.0; MoO ₃ - 1.5; WO ₃ - 1.0; CaO - 3.0; Portland cement - 6.0.

The catalyst is subjected to artificial aging and experience analogously to example 17.

The test data for the catalyst are shown in table 2.

Table 1 Index / Example No. Hydrocarbon conversion selectivity Index / Example No. Hydrocarbon conversion selectivity one ethylbenzene 82.5 94.5 eleven ethylbenzene 82.6 95.2 2 ethylbenzene 82.7 94.4 12 ethylbenzene 83.3 94.6 3 ethylbenzene 82.6 94.4 13 ethylbenzene 84.0 94.4 four ethylbenzene 82.7 94.5 fourteen isopropylbenzene 78.1 94.6 5 ethylbenzene 82.7 94.6 fifteen isopropylbenzene 78.7 96.4 6 ethylbenzene 83.0 94.4 16 isopropylbenzene 79.2 96.1 7 ethylbenzene 82.8 94.4 8 ethylbenzene 82.7 95.5 9 ethylbenzene 82.9 94.4 10 ethylbenzene 83,2 94.7

table 2 Index / Example No. Hydrocarbon Activity before artificial aging Activity after artificial aging Conversion,% of the mass. Selectivity,% mass Conversion,% of the mass. Selectivity,% mass 17 ethylbenzene 82.5 94.5 79.7 94.5 eighteen ethylbenzene 82.7 94.4 80.1 94.3 19 ethylbenzene 82.6 94.4 81.3 94.6 twenty ethylbenzene 81.2 94.2 77.3 94.0

Claims (5)

1. The catalyst for the dehydrogenation of alkylaromatic hydrocarbons, including iron oxide, potassium compounds, magnesium compounds and / or calcium compounds, molybdenum oxide, cerium oxide and Portland cement, characterized in that it further comprises lanthanum oxide and / or neodymium oxide in the following ratio of components, wt.%: Potassium compounds (in terms of potassium oxide) 8.0-25.0 Compounds of magnesium and / or calcium compounds (in terms of magnesium oxide and / or calcium oxide) 0.2-7.0 Molybdenum oxide 0.7-7.0 Cerium oxide 1.0-15.0 Portland cement 0.5-12.0 Lanthanum oxide and / or neodymium oxide 0.01-7.0 Iron oxide Rest 2. The catalyst according to claim 1, characterized in that as a potassium compound it contains potassium polyferrites. 3. The catalyst according to claim 1 or 2, characterized in that it is molded in the form of three to five petal granules. 4. The catalyst according to claim 1 or 2, characterized in that it further comprises zirconium oxide, tin oxide and tungsten oxide in an amount of 0.01-1.0 wt.% Each. 5. The catalyst according to claim 4, characterized in that it is molded in the form of three to five petal granules.

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