CS207173B1 - Synthetic aluminosilicate catalyzer for the catalythic conversion of hydrocarbon and method of making the same - Google Patents

Description

The invention relates to a synthetic aluminosilicate catalyst for the catalytic conversion of hydrocarbons and to a process for its production.

Catalytic conversion of hydrocarbons in the present invention is understood to mean catalytic cracking, alkylation, de-alkylation, disproportionation, isomerization, and similar types of hydrocarbon conversions through the mechanisms of carbene ions in the presence of acid catalysts.

In many chemical processes, natural or synthetic aluminosilicates which are either amorphous or crystalline are used as catalysts. Crystalline aluminosilicates are in most cases more active than amorphous. Synthetic crystalline aluminosilicates are among the most active and selective catalysts in processes such as catalytic cracking, alkylation, de-alkylation, disproportionation, isomerization and similar types of catalytic conversion.

The synthetic aluminosilicate catalyst of the present invention is a layered aluminosilicate whose crystalline structure contains, in addition to silicon and aluminum, some metals whose presence substantially enhances the catalytic activity of the catalysts of the present invention in the hydrocarbon conversions occurring by the meohanism of carbenium ions. The novel type catalysts described in the present invention have a summary empirical formula

207 173

207 173 m SiOg t n AlgO ^ i p QO i Dit in which it means

SiOg silicon dioxide

AlgO4 aluminum oxide

QO of metal heated by copper, beryllium, zinc, nickel, cobalt and mixtures thereof

D equivalent of an anion selected from the group consisting of hydroxyl anion, fluoride anion, oxygen anion and mixtures thereof

M equivalent of a replaceable cation selected from the group consisting of hydrogen, ammonium, alkali metal, alkaline earth metal cations and mixtures thereof,

m my value from 2.01 to 3.97 n my value from 0.02 to 2.96 P my value from 0.03 to 3.50 with my value from 0.03 to 1.00

The catalysts of the present invention are prepared by hydrothermal synthesis of an aqueous slurry containing silica, alumina, divalent metal cations (mecl, beryllium, zinc, nickel, cobalt), alkali metal, alkaline earth metal or ammonium hydroxides and fluorides, and their relative to each other. mixture.

The hydrothermal synthesis is carried out in a pressure vessel, autoclave, at a temperature of from 160 ° C to 350 ° C at an autogenous pressure of water vapor. Effective mixing of this aqueous suspension is very advantageous and contributes to the reduction of the time required to form synthetic crystalline aluminosilicate. After completion of the synthesis, the contents of the autoclave are cooled and the resulting crystalline product is separated from the mother liquor by filtration, sedimentation or centrifugation. The separated synthetic aluminosilicate may be washed with distilled or deaiineralized water and / or ammonium hydroxide solution. The material which has been synthesized in the presence of alkali or alkaline earth metal hydroxides and fluorides is preferably subjected to ion exchange with ammonium salt solutions such as ammonium nitrate or ammonium chloride. using other ammonium salts gives similar results.

The crystalline aluminosilicate thus obtained is dried and calcined at a temperature of from 250 ° C to 750 ° C. The ammonium ion decomposes to give a product in a hydrogen form, which is catalytically very effective in the conversion of hydrocarbons occurring by the mechanism of carbenium ions such as catalytic cracking, alkylation, disproportionation, isophthalization and the like.

The following examples illustrate the preparation method and catalytic activity of the catalysts prepared according to the present invention without limiting the scope of the present invention in any way.

207 173

Example 1

A 2 liter vessel was charged with 135 g of silica hydrosol, 500 ml of demineralized water and 30.2 g of aluminum chloride hexahydrate dissolved in 500 ml of demineralized water. Under vigorous stirring, a 14% ammonium hydroxide solution was added until the pH of the mixture reached 10. The aluminum and silicon passed into a gel which was filtered off and washed with demineralized water until the reaction to chloride ions disappeared in the filtrate.

The washed gel was diluted with 1000 ml of demineralized water and 77.8 g of nickel acetate tetrahydrate dissolved in 500 ml of water was added with stirring. After homogenization of the resulting mixture, a solution of 2.04 g of ammonium fluoride and 10 ml of a 20% ammonium hydroxide solution was added. The reaction gel thus prepared was transferred to an autoclave where it was subjected to a hydrothermal synthesis for 72 hours at 250 ° C and the autogenous water vapor pressure.

The hydrothermal synthesis product was filtered from the mother liquor and washed with 2500 ml of 10% ammonium hydroxide solution. After drying at 120 ° C, the product was calcined at 500 ° C for 5 hours. The catalyst obtained was designated as SAN.

Part of the material was subjected to X-ray before calcination. diffraction analysis, which showed it to be a crystalline layered aluminosilicate having a baseline of _Q0 = 1.3 nm, at 60% relative humidity. humidity.

Example 2

In a 2 L flask was added a solution of 12 g of aluminum chloride hexahydrate, a solution of 28 g of beryllium sulfate tetrahydrate, and 88 g of silica hydrosol. The resulting mixture was made up to 1000 ml with distilled water and concentrated ammonium hydroxide solution was added under vigorous stirring until the pH of the mixture reached 10. The resulting goal was filtered off and washed with distilled water until the reaction to chloride and sulfate ions disappeared in the filtrate.

The filtered gel was diluted to 1000 ml with distilled water and, with stirring, successively added concentrated solutions of nickel acetate tetrahydrate (58.4 g), 2.1 g ammonium fluoride, 1.45 g sodium hydroxide and 10 ml ammonium hydroxide / 20 ml. The resulting reaction mixture, to which 800 ml of distilled water was added, was transferred to an autoclave where it was subjected to hydrothermal synthesis at 285 ° C for 44 hours.

The hydrothermal synthesis product was filtered from the mother liquor, then dispersed in 3000 ml of a 20% ammonium hydroxide solution, where it was subjected to ion exchange for 12 hours. at 25 ° C. After filtration and drying at 120 ° C, the product was calcined at 700 ° C. This product has been designated SABN,

Part of the material was subjected to X-ray before calcination. diffraction analysis, which showed it to be a layered crystalline aluminosilicate having a baseline of? qq => 1.26 nm at 60% relative humidity.

207 173

Example 3

192 g of silica hydrosol was mixed with a solution of 41.7 g of aluminum chloride hexahydrate and the volume of the mixture was made up to 500 ml with distilled water. With vigorous stirring, concentrated ammonium hydroxide was added to pH 10. The resulting gel was homogenized for 3 hours, then filtered and washed with distilled water. 3.7 g of ammonium fluoride, a solution of 105 g of copper acetate monohydrate and 15 ml of ammonium hydroxide solution were then added to the gel. The resulting mixture was made up to 2300 mL with water and subjected to hydrothermal synthesis at 295 ° C for 36 hours. The hydrothermal synthesis product was dispersed in 4500 ml of 10% ammonium hydroxide solution, filtered off and dried at 110 ° C. The dried material was calcined at 510 ° C for 2 hours and the resulting catalyst was designated SAM,

Example 4

To a hydrous sol of 220 g of silica was added 500 ml of a solution in which 23 g of aluminum chloride hexahydrate was dissolved and the mixture was precipitated with 10% ammonium hydroxide solution to pH 10. The resulting gel was filtered, washed with distilled water and then 500 ml was added. solution in which 40.5 g of sodium fluoride was dissolved. 900 ml of a solution containing 120 g of zinc nitrate was gradually added to this mixture with vigorous stirring. Finally, 25 ml of concentrated ammonium hydroxide solution was added and the resulting mixture was quantitatively transferred to an autoclave where it was subjected to synthesis at 310 ° C for 36 hours. The hydrothermal synthesis product was treated by ion exchange with 0.5 N ammonium nitrate solution at 80 ° C. The crystallized material so treated was dried at 105 ° C and calcined in the presence of air at 520 ° C for 3 hours. The catalyst obtained was designated SAZ.

Example 5

In a 4 L aa flask was added 200 g of silica hydrosol and a solution of 45.2 g of aluminum chloride hexahydrate was added so that the total volume of the mixture was 0000 ml.

The mixture was heated to 60 ° C with stirring, then 20% ammonium hydroxide solution was slowly added until the pH of the mixture reached 10. The resulting gel was filtered and washed with demineralized water until the positive reaction to chloride ions disappeared. The filtered gel was dispersed in demineralized water and 120 g of cobalt acetate tetrahydrate dissolved in a minimum of water was added with stirring, followed by a solution of 4.9 g of ammonium fluoride and finally 28 ml of a 26% ammonium hydroxide solution were added. The resulting mixture was transferred to an autoclave where it was synthesized at 310 ° C for 15 hours. The product obtained was washed with 3500 ml of 10% ammonium hydroxide solution and dried at 110 ° C for 2 hours. calcined at 280 ° C. The product was designated SAK. Its X-ray. diffraction analysis showed it to be a layered crystalline material with a baseline of Qq = 1.07nm. Example 6

The catalytic activity of the catalysts of the present invention was monitored using a conventional type flow apparatus on a model reaction. conversion of toluene, which in the reaction zone of the reactor is de-alkylated to benzene, disproporoionizes to benzene and xylenes, which

207 173 further isomerize. This model type of reaction provides data on the de-alkylated-alkylation, disproportionation and isomerization activity of the investigated catalysts.

The reaction products were analyzed by gas chromatography. The toluene conversion was calculated according to the conversion = 100 -% unconverted toluene /% mol /

Table 1 summarizes the results of measurements of the catalytic activity of the catalysts of the present invention and also compares the catalytic activity of a cracking catalyst based on decationized Y-type zeolite.

Table 1

Toluene conversion at 500 ° C catalyst conversion mol% selectivity conversion SAN 49.90 94.22 Sabnie 43,15 95.16 SAK 42.92 97.08 ON MY OWN 44.38 83.51 SAZ 47.54 93.56 Y-zeolite 45,34 94.85

The selectivity of the conversion was calculated according to the ratio of selectivity - 100 $ ^m ? A · ^ énu + + ff.mol.xylenes% mole conversion

As shown experimentally in Table 1, the catalysts of the present invention have a high catalytic activity and at the same time a very good selectivity.

Claims (4)

OBJECT OF THE INVENTION 1. Synthetic aluminosilicate catalyst for the catalytic conversion of hydrocarbons such as catalytic cracking, alkylation, de-alkylation, isomerization, disproportionation and similar types of hydrocarbon conversion through a carbene ion mechanism, characterized in that it consists of a synthetic layered alumina silicate AlgO 2: p QO t DM in which is Si0 ₂ silicon dioxide AlgO ^ j aluminum oxide w A metal oxide heated by the group consisting of honey, beryllium, zinc, nickel, cobalt and mixtures thereof, D equivalent of an anion selected from the group consisting of hydroxyl anion, fluoride anion, oxygen anion, and mixtures thereof, M equivalent of a replaceable cation selected from the group consisting of ammonium hydrogen, alkali metal, alkaline earth metal and mixtures thereof, m having a value of from 2.01 to 3.97 n having a value of from 0.02 to 2.96 p having a value of from 0.03 to 3.50 b is from 0.03 to 1.00 2. A process for the production of a synthetic aluminosilicate catalyst for the catalytic conversion of hydrocarbons according to claim 1, characterized in that the mixture of starch materials, preferably in aqueous solutions containing alumina, silica, divalent metal cations selected from the group consisting of honey, beryllium, zinc cobalt, nickel, and mixtures thereof, together with anions selected from the group consisting of hydroxyl anion, fluoride anion, oxygen anion, and mixtures thereof, are subjected to hydrothermal synthesis at temperatures from 160 ° C to 350 ° C at the corresponding water vapor pressure. 3. A process for producing a synthetic aluminosilicate catalyst for the catalytic conversion of hydrocarbons according to items 1 and 2, characterized in that the synthesized catalyst is subjected to an ion exchange with ammonium salt or ammonium hydroxide solutions. 4. Synthetic aluminosilicate catalyst for the catalytic conversion of hydrocarbons according to items 1, 2 and 3, characterized in that it is subjected to a heat treatment by heating to temperatures in the range of 280 ° C to 75 ° C, preferably 450 ° 0 to 650 ° C.