RU2361667C1 - Catalyst for dehydrogenating olefin hydrocarbons - Google Patents

Abstract

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

Description

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

A known catalyst for the dehydrogenation of olefinic hydrocarbons of the following composition, wt.%: Zirconium dioxide 1.0-3.0; potassium oxide 10.0-20.0; rubidium or cesium oxide 0.1-5.0; silicon dioxide 0.5-1.2; alumina 0.1-5.0; chromium oxide 2.0-5.0; iron oxide - the rest (RF patent No. 1608917 from 09.20.88 publ. B.I. No. 25.1996, B01J 23/86, C07C 5/333).

Closest to the proposed is a catalyst for the dehydrogenation of olefinic hydrocarbons, containing, wt.%: Zirconium dioxide 1.0-3.0; potassium oxide - 10.0-20.0; rubidium or cesium oxide 0.1-5.0; silicon dioxide 0.5-1.7; alumina 0.1-5.0; chromium oxide 2.0-5.0; magnesium oxide and / or calcium 1.0-10.0; copper oxide 0.05-2.0; iron oxide - the rest, (RF patent No. 21116830 from 04/18/1997, publ. 08/10/98, B.I. No. 22, B01J 23/86).

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 and selectivity of the catalyst.

A catalyst is proposed for the dehydrogenation of olefinic hydrocarbons based on iron oxide, including potassium compounds, chromium oxide and additionally containing molybdenum oxide, cerium oxide and Portland cement in the following ratio, wt.%:

potassium compounds (in terms of potassium oxide) 10.0-25.0 chromium oxide 0.5-7.0 molybdenum oxide 0.7-7.0 cerium oxide 1.0-15.0 Portland cement 0.5-13.0 iron oxide 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 .

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 and the prototype is the additional content of cerium oxide, molybdenum oxide and Portland cement 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;

- 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 and selectivity 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 finely ground oxides or compounds of iron, molybdenum, and cerium that decompose to oxides. 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 1.5-3.0 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 use to prepare the catalyst at the stage of mixing the dry components. 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 molded by extrusion into cylindrical or three to 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 O ₃ ), molybdenum oxide, cerium oxide, Portland cement, chromium 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 115 ° C and calcined at 650 ° C for 3 hours.

Get the catalyst composition, wt.%: Fe ₂ O ₃ - 62.5; K ₂ O - 19.0; Cr ₂ O ₃ - 2.5; MoO ₃ - 1.0; CeO ₂ - 9.0; Portland cement - 6.0.

Tests of the catalyst are carried out in the reaction of dehydrogenation of isoamylenes to isoprene at a temperature of 620 ± 20 ° C, a feed rate of liquid isoamylenes of 0.5-1.5 l / l of catalyst per hour and mass dilution of the feedstock with steam 1: 4-6. The test data of the catalyst are shown in table 1.

Example 2

The catalyst is prepared analogously to example 1, but instead of a solution of potassium carbonate, a solution of potassium alkali KOH is used and the ratio of components is changed.

Get the catalyst composition, wt.%: Fe ₂ O ₃ - 54.5; K ₂ O - 25.0; Cr ₂ O ₃ - 3.5; MoO ₃ - 1.0; CeO ₂ - 10.0; Portland cement - 6.0.

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 the ratio of components is changed.

Get the catalyst composition, wt.%: Fe ₂ O ₃ - 68.5; K ₂ O - 8.0; Cr ₂ O ₃ - 2.5; MoO ₃ - 7.0; CeO ₂ - 1.0; Portland cement - 13.0;

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 the ratio of components is changed.

Get the catalyst composition, wt.%: Fe ₂ O ₃ - 71.5; K ₂ O - 8.0; Cr ₂ O ₃ - 0.7; MoO ₃ - 7.0; CeO ₂ - 2.8; Portland cement - 10.0.

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 the ratio of components is changed.

Get the catalyst composition, wt.%: Fe ₂ O ₃ - 67,0; K ₂ O - 20.0; Cr ₂ O ₃ - 7.0; MoO ₃ - 0.7; CeO ₂ - 4.8; Portland cement - 0.5.

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.

Get the catalyst composition, wt.%: Fe ₂ O ₃ - 70.8; K ₂ O - 18.0; Cr ₂ O ₃ - 0.7; MoO ₃ - 2.0; CeO ₂ - 3.5; Portland cement - 5.0.

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 1, but as a potassium compound, pre-prepared potassium polyferrite is also used. Get the catalyst composition, wt.%: Fe ₂ O ₃ - 59.00; K ₂ O - 19.5; potassium polyferrite (based on

K ₂ O) - 1.5; Cr ₂ O ₃ - 5.0; MoO ₃ - 1.0; CeO ₂ - 7.0; Portland cement - 7.0.

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 3, but the ratio of components is changed. The composition of the obtained catalyst is as follows, wt.%: Fe ₂ O ₃ - 69.0; K ₂ O - 11.5; Cr ₂ O ₃ - 0.5; MoO ₃ - 1.0; CeO ₂ - 15.0; Portland cement - 3.0.

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 3, but the ratio of components is changed. The composition of the obtained catalyst is as follows, wt.%: Fe ₂ O ₃ - 69.0; K ₂ O - 10.0; Cr ₂ O ₃ - 0.5; MoO ₃ - 1.0; CeO ₂ - 12.0; Portland cement - 7.5.

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 3, but the ratio of components is changed. The composition of the obtained catalyst is as follows, wt.%: Fe ₂ O ₃ - 68.5; K ₂ O - 21.5; Cr ₂ O ₃ - 1.5; MoO ₃ - 2.0; CeO ₂ - 1.0; Portland cement - 5.5.

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 1, but is formed into three-petal granules with d ₁ = 3.0 mm; d ₂ = 1.9 mm (Fig. 1). The catalyst was tested in the isoamylene dehydrogenation reaction under the conditions described in Example 1. The catalyst test data are shown in Table 1.

Example 12

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

Example 13

The catalyst is prepared analogously to example 1, but it is tested in the dehydrogenation reaction of n-butylenes in butadiene at a temperature of 620 ± 20 ° C, a feed rate (by gas) of 600 h ^-1 and a molar dilution of the feed with steam of 1:13. The test data of the catalyst are shown in table 1.

Example 14

The catalyst is prepared analogously to example 2, but is tested in the dehydrogenation reaction of n-butylene to butadiene under the conditions described in example 11. The catalyst test data are shown in table 1.

Example 15

The catalyst is prepared analogously to example 3, but is tested in the dehydrogenation reaction of n-butylene to butadiene under the conditions described in example 11. The test data for the catalyst are shown in table 1.

Example 16

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 ), magnesium oxide, reprecipitated aluminum hydroxide, copper oxide, chromium oxide, calcium oxide are mixed for 1 hour. An aqueous solution of potassium and cesium carbonates and potassium silicate are added. The catalyst mass is stirred for 2.0 hours until a homogeneous mass is obtained, 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 O ₃ - 68.6; K ₂ O - 12.0; Cs ₂ O - 1.6; MgO - 5.0; Cr ₂ O ₃ - 3.5; СuО - 1.0; SiO ₂ - 1.2; ZrO - 1.0; Al ₂ O ₃ - 2.6; CaO - 3.5.

The catalyst is tested analogously to example 1.

The test data for the catalyst are shown in table 1.

Claims (3)

1. The catalyst for the dehydrogenation of olefinic hydrocarbons based on iron oxide, including potassium compounds, chromium oxide, characterized in that it further comprises molybdenum oxide, cerium oxide and Portland cement in the following ratio, wt.%:
potassium compounds (in terms of potassium oxide) 10.0-25.0 chromium oxide 0.5-7.0 molybdenum oxide 0.7-7.0 cerium oxide 1.0-15.0 Portland cement 0.5-13.0 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.

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