DE4006884C2 - Catalysts for the production of high octane gasolines, their production and their use - Google Patents

Description

The invention relates to novel, highly selective catalysts ren, especially for the production of gasoline with high Octane number through naphtha reforming, as well as for dehydration tion, dehydrogenative ring cleavage and isomerization of Naphthenes and paraffins, especially for aromatics lung.

There are already various catalysts for naphtha re formation known from metals of groups IV A and VIII B of the periodic table exist and at the same time continuous or gradual impregnation of a carrier with Complex compounds or by coagulating one or more rer metals in the manufacture of supports the. The carrier material can be made from a natural or artificial oxide or a corresponding oxide mixture stand, for example made of aluminum oxide, aluminum silica magnesium oxides, bentonite, diatomaceous earths, silica the or zeolite crystals.  

Reforming is generally moderate in the presence acidic catalysts performed. This limits the out choice of carrier materials; the usual carriers materials are therefore magnesium oxide and aluminum oxide, especially in highly pure form and in the form of γ- or η- Modification.

Previously used metals from Group IV A of Periodensy stems are tin, germanium and lead; from group VIII B So far mainly cobalt, nickel, ruthenium, Rhodium and palladium as well as osmium, iridium and platinum used.

US 3 883 419 A relates to a method of manufacture of a platinum-tin catalyst for hydrocarbon Change in the reforming of naphtha by successive changes subsequently impregnating a support with platinum and tin in an inert gas and methanol atmosphere, drying, baking NEN and activation of the catalyst obtained.

US 3 994 832 A relates to a method of manufacture of a platinum-tin catalyst for catalytic reform mation of hydrocarbons to produce Ben High octane gasoline or aromatics where the the catalytically active metals on a heat resistant nigen, inorganic oxide can be applied as a carrier. The carrier material is pre-chelated treated.

FR 20 240 is a catalyst for reforming and Isomerization of hydrocarbons to produce High octane gasoline known from platinum, Tin, chlorine and a metal from groups IA and IIA  of the periodic table and by double imprints nation of a carrier material from, for example, a inorganic oxide is produced.

US 4,529,505 A is a process for the manufacture of a Catalyst for reforming hydrocarbons the extraction of petrol with a high octane number made of platinum, tin and indium and by tin coagulation with an aluminum trichloride solution under Carrier formation, impregnation of the carrier from γ-aluminum oxide with an acidic platinum solution and subsequent Drying and burning is made.

FR 2 545 380 A relates to a manufacturing process of an acidic catalyst for reforming coal water materials for the production of petrol and aromatic Hydrocarbons made from platinum, tin, germanium and There is lead and in which the tin is matched by a de Organometallic compound is introduced.

Finally, a method for de Hydrogenation and ring cleavage of hydrocarbons known low pressure, in which a catalyst from Pla tin, tin and rhodium is used by impregnation tion, coagulation and coprecipitation of the metals on egg nem inorganic carrier is produced.

From DE 37 20 522 A1 platinum and tin and halogen-containing catalysts were known, which by impregnating a carrier, for. B. made of aluminum oxide, with a tin salt solution and a platinum salt solution and a halogen bond. The halogen can be introduced both in the form of the corresponding metal halides and in the form of hydrohalic acid. The tin content of the known catalysts is 0.05 to 3 mass%, the platinum content 0.01 to 2 mass% and the halogen content 0.1 to 15 mass%.

The invention has for its object catalysts, which in particular for the production of petrol with high Octane number due to naphtha reforming and dehydration tion, dehydrogenative ring cleavage and isomerization of Naphthenes and paraffins are suitable, as well as processes specify their manufacture and use, whereby the catalytically active metals as fine as possible on the Carrier surface should be distributed; the catalysts should be regenerable continuously or discontinuously be and in reforming Naphtha and the Dehy dration, the dehydrogenative ring cleavage and the isomeri High selectivity of naphthenes and paraffins have. Furthermore, an increased yield of aromati hydrocarbons and therefore a higher ok number of corresponding gasoline can be achieved. The Kataly sators should also have high stability in their physi and chemical properties to a repeated use under the difficult conditions to allow for naphtha reforming.

The task is solved according to the independent claims. The subclaims relate to advantageous embodiments concept of invention.

The catalysts of the invention comprise a support made of aluminum oxide, contain 0.34 to 0.39% by mass of tin and 0.33 to 0.39% by mass of platinum and halogen and are  by impregnating the support with a solution of a Tin compound and an aqueous solution of a Platinum compound in the presence of a hydrogen halide acid available; they are ge according to the invention indicates that they are available through

• (A) impregnating the support with an aqueous solution of
  • (a) tin (II) chloride and / or tin (IV) chloride as tin compounds,
  • (b) hydrofluoric acid, hydrochloric acid and / or hydrobromic acid as Halogenwas serstoffsäurischen
    and
  • (c) citric acid and / or oxalic acid as organic acids in an amount of 0.01 to 20% by mass and in particular 0.1 to 15% by mass, based on the mass of the carrier used, in an inert gas atmosphere or in air,
• (B) stabilizing the impregnated support in one Inert gas atmosphere or in the air during a Time from 10 min to 5 h and in particular 0.5 to 3h,
• (C) drying the impregnated support at 100 to 150 ° C and especially at 110 to 130 ° C during a time of 1 to 5 hours,  
• (D) firing the product from step (c) at 450 to 650 ° C and especially at 500 to 600 ° C during one Time from 2 to 10 hours and especially 3 to 8h,
• (E) impregnating the product from step (D) with an aqueous solution of
  • (a) Chloroplatinic acid and / or ammonium chloroplatinate as platinum compounds
    and
  • (b) hydrofluoric acid, hydrochloric acid and / or hydrobromic acid as Halogenwas serstoffsäurischen
    in a CO₂ atmosphere
• (F) stabilizing the impregnated product from step (E) in a CO₂ atmosphere,
• (G) drying at 50 to 150 ° C and especially at 90 to 130 ° C for a period of 1 to 15 h and especially 2 to 6 h
• (H) firing the product from step (G) in an oxidizing atmosphere at 300 to 600 ° C and in particular 400 to 550 ° C for a time of 1 to 6 h and in particular 1 to 5 h
  and
• (I) activate the catalyst obtained in reduced render atmosphere, especially a hydrogen atmosphere, at 350 to 600 ° C for a period of 1 to 6 h.

The process according to the invention for producing this kata Lysators is equivalent through the above procedure steps (A) to (I) marked.

In step (A), citric acid or Oxalic acid is used, with citric acid being preferred.

In the context of the invention, the impregnation of the carrier with the tin compound in step (A) in the presence of the Ha hydrochloric acid and citric acid and / or oxal acid made; this is a particularly fine Ver division of the catalytically active metals achieved.

The tin content of the catalysts is preferably 0.35 up to 0.38% by mass.

The platinum concentration of the catalysts is preferred 0.35 to 0.38 mass%.

The carrier material is generally an aluminum oxide, with γ- and η-alumina are preferred.

The halogen compound is advantageously used in step (A) in an amount used which is 0.1 to 80% and preferably 20 to 80% of the halogen required for the catalyst delivers.  

The aqueous solution used in step (A) as well as the Im used for impregnation in step (E) impregnation solution represent aqueous solutions that partially produced with deionized water.

The impregnation solution used in step (E) contains the Halogen compound in an amount that is 20 to 100% and preferably 30 to 80% of that required for the catalyst supplies halogens.

The individual process steps of the invention Process can be at atmospheric pressure as well against higher or lower pressures will; it is also within the scope of the concept of the invention possible, individual steps at atmospheric pressure and others re steps at higher or lower Perform printing.

The specific surface area used in step (A) Carrier is advantageously 100 to 500 m² / g and above preferably 150 to 250 m² / g. The inventive method leads to practically no relevant change in the specific surface of the carrier used.

The same applies to the pore volume of the used Support or the resulting catalysts, the 0.3 to 1.0 ml / g and preferably 0.4 to 0.7 ml / g wearing.

The catalysts of the invention are notable for high activity and high selectivity from what in particular re in naphtha reforming and dehydration, the  dehydrogenative ring cleavage and the isomerization of Naphthenes and paraffins for the production of beating solid petrol with a high octane number and aromatics can be exploited.

The catalysts of the invention also lead to high Turning hydrocarbons into high-quality substances (High octane gasolines, aromatics such as benzene, toluene and xylenes, as well as ethylbenzene and liquid petroleum gases).

The catalysts of the invention have favorable physi potash and chemical properties, especially ho he physical and chemical stability, and can be regenerated, which is discontinuous as well as con can be done continuously. The high regenerability rests particularly on the low thermal expansion and the high mechanical resistance of the catalytic converter gates correspondingly at temperatures up to about 550 ° C, for example for naphtha reforming can be set. Even with continuous rain cheap mechanical and catalytic remain Get properties.

Due to the special manufacture of the catalysts impregnation twice under the Be specified above conditions and in the presence of a compensating agent that during the impregnation process at the right time and is added in the appropriate amount, a particular achieves fine metal distribution on or in the carrier, which in turn with the high catalytic effectiveness kor is relatable.  

The invention is described below with reference to exemplary embodiments play explained with reference to the figures; it demonstrate:

Figure 1 shows the dependence of the octane number of gasolines obtained by catalytic reforming of naphtha on the working temperature for 3 catalysts of the invention.

FIG. 2 shows the relationship between yield and octane number for the 3 catalysts according to the invention from FIG. 1;

Fig. 3 shows the dependence of the octane number on the working temperature for a catalyst according to the invention in new condition and after regeneration and

Fig. 4 shows the relationship between yield and octane number for the catalyst of Fig. 3 in new condition and after regeneration.

example 1

Using spheres made of high-purity γ-aluminum oxide with an average diameter of 1.77 mm, a specific surface of 199 m² / g and a pore volume of 0.49 ml / g as a support material, a catalyst was produced as follows:
A solution of 0.7036 g SnCl₂ · 2 H₂O and 0.4395 ml hydrochloric acid (36.5 - 37.5%) containing 0.25 g / ml citric acid was mixed with 98.26 g of the carrier material for the first impregnation brought together. The product was stabilized in air at room temperature for 1 hour. Then it was dried at temperatures in the range of 100 to 150 ° C and baked at a temperature in the range of 450 to 550 ° C for 3 to 6 hours.

The product obtained was then washed with water impregnated solution, the 0.779 g chloroplatinic acid and contained 0.4395 ml of hydrochloric acid. Get that The product was dried with 120 ° C hot air and 1 h at a temperature in the range of 450 to 550 ° C ge burns. After the analysis, the catalyst was in a Hydrogen atmosphere reduced and thus activated.

In this way, a catalyst A with a very high hen obtained degree of dispersion of the metal, the 0.37 mass% Platinum, 0.37 mass% tin and 0.98 mass% chlorine contained. The specific surface was 199 m² / g, the pore volume men 0.489 ml / g.

Example 2

From 0.7036 g tin (II) chloride, 0.44 ml HCl (36.5- 37.5%) and 65 ml of deionized water, an Im pre-made solution. It became the same dream germ material as in Example 1 under a nitrogen atmosphere impregnated. The product was under nitrogenate for 20 min stabilized and then dried at 120 ° C and Fired at 450 to 550 ° C.

The product was then simulated as in Example 1 impregnated, dried and burned.

In this way, a catalyst B was obtained with the following properties:
0.36 mass% platinum; 0.36 mass% tin; 0.97 mass% chlorine; specific surface area 199 m² / g; Pore volume 0.49 ml / g.

Example 3

Using a carrier material made of γ-aluminum oxide in the form of spheres with a specific surface of 193 m² / g and a pore volume of 0.679 ml / g 100 g of a catalyst according to the procedure of Example 1 manufactured.

The catalyst C obtained had the following properties:
0.386 mass% platinum; 0.337 mass% tin; 0.89% by mass of chlorine; specific surface 190 m2 / g; Pore volume 0.673 ml / g.

Example 4

This example relates to the investigation and loading evaluation of the kata prepared in Examples 1 to 3 Analyzers A, B and C in a pilot plant in a continuous Nuclearly operated fixed bed reactor.

The following product was launched:
Material: naphtha
Sulfur: 0.87 ppm
Density (20/4 ° C): 0.7283 g / ml
Initial boiling point: 50 ° C
Final boiling point: 195 ° C.

The tests were carried out at 490 to 520 ° C and under a pressure of 10.2 bar; the Raumge speed of the liquid (LHSV) was 2.2 h ^-1 , the molar ratio H₂ / hydrocarbons 3.7.

The results obtained are shown in FIGS. 1 and 2 for the three catalysts A, B and C. The results show that the catalysts of the invention have high activity and selectivity in the conversion of paraffin and naphthenic hydrocarbons in naphtha reforming for the production of petrol with a high octane number.

Example 5

Based on the test results shown in FIGS . 1 and 2, the catalyst A was selected in order to investigate its regenerative capacity. The test conditions were as in Example 4.

The reaction conditions were:
Temperature: 450 ° C
Pressure: 4.9 bar
O₂ concentration: 2 vol.%.

The results obtained are shown in FIGS. 3 and 4. It can be seen from this that the activity of the catalyst was practically completely restored after the regeneration.

Tables 1 and 2 contain the analytically determined ones Properties of the investigated catalysts according to the invention gates A, B and C shown.  

Table 1

Table 2

Properties of the new and regenerated catalyst A

Claims (9)

1. Catalysts, especially for the production of high octane gasolines by naphtha reforming and for dehydration, dehydrogenative ring cleavage and isomerization of naphthenes and paraffins, the 0.34 to 0.39% by weight of tin and 0.33 to 0.39 % By mass of platinum and halogen on aluminum oxide as carrier and are obtainable by impregnating the carrier with a solution of a tin compound and an aqueous solution of a platinum compound in the presence of a hydrohalic acid, characterized in that they are obtainable by

• (A) impregnating the support with an aqueous solution of
  • (a) tin (II) chloride and / or tin (IV) chloride as tin compounds,
  • (b) hydrofluoric acid, hydrochloric acid and / or hydrobromic acid as hydrohalic acids
    and
  • (c) citric acid and / or oxalic acid in an amount of 0.01 to 20% by mass and in particular 0.1 to 15% by mass, based on the mass of the carrier used, in an inert gas atmosphere or in air,
• (B) stabilizing the impregnated carrier in an inert gas atmosphere or in air for a period of 10 minutes to 5 hours and in particular 0.5 to 3.0 hours,
• (C) drying the impregnated support at 100 to 150 ° C. and in particular at 110 to 130 ° C. for a period of 1 to 5 hours,
• (D) firing the product from step (C) at 450 to 650 ° C. and in particular at 500 to 600 ° C. for a period of 2 to 10 h and in particular 3 to 8 h,
• (E) impregnating the product from step (D) with an aqueous solution of
  • (a) Chloroplatinic acid and / or ammonium chloroplatinate as platinum compounds
    and
  • (b) hydrofluoric acid, hydrochloric acid and / or hydrobromic acid as hydrohalic acids
    in a CO₂ atmosphere,
• (F) stabilizing the impregnated product from step (E) in a CO₂ atmosphere;
• (G) drying at 50 to 150 ° C. and in particular at 90 to 130 ° C. for a time of 1 to 15 h and in particular 2 to 6 h,
• (H) firing the product from step (G) in an oxidizing atmosphere at 300 to 600 ° C and in particular 400 to 550 ° C for a time of 1 to 6 h and in particular 1 to 5 h
  and
• (I) activating the catalyst obtained in a reducing atmosphere, in particular a hydrogen atmosphere, at 350 to 600 ° C. for a period of 1 to 6 hours.

2. Catalysts according to claim 1, characterized by γ-aluminum minium oxide and / or η-aluminum oxide as a carrier. 3. Catalysts according to claim 1 or 2, characterized by a specific surface in the range of 100 to 500 m² / g and preferably 150 to 250 m² / g. 4. Catalysts according to claims 1 to 3, characterized by a pore volume of 0.3 to 1.0 ml / g and preferably 0.4 to 0.7 ml / g. 5. Process for the preparation of the catalysts according to claims 1 to 4 by impregnating the support from aluminum oxide with a solution of a tin compound and an aqueous solution of a platinum compound in the presence of a hydrohalic acid, characterized in that

• (A) the carrier with an aqueous solution of
  • (a) tin (II) chloride and / or tin (IV) chloride as tin compounds,
  • (b) hydrofluoric acid, hydrochloric acid and / or hydrobromic acid as hydrohalic acids
    and
  • (c) citric acid and / or oxalic acid in an amount of 0.01 to 20% by mass and in particular 0.1 to 15% by mass, based on the mass of the carrier used, impregnated in an inert gas atmosphere or in air,
• (B) the impregnated carrier is stabilized in an inert gas atmosphere or in air for a period of 10 minutes to 5 hours and in particular 0.5 to 3.0 hours,
• (C) the impregnated carrier is dried at 100 to 150 ° C. and in particular at 110 to 130 ° C. for a period of 1 to 5 hours,
• (D) the product from step (C) is fired at 450 to 650 ° C. and in particular at 500 to 600 ° C. for a period of 2 to 10 hours and in particular 3 to 8 hours,
• (E) the product from step (D) with an aqueous solution of
  • (a) Chloroplatinic acid and / or ammonium chloroplatinate as platinum compounds
    and
  • (b) hydrofluoric acid, hydrochloric acid and / or hydrobromic acid as hydrohalic acids
    impregnated in a CO₂ atmosphere,
• (F) stabilizing the impregnated product from step (E) in a CO₂ atmosphere,
• (G) dried at 50 to 150 ° C. and in particular at 90 to 130 ° C. for a time of 1 to 15 h and in particular 2 to 6 h,
• (H) the product from step (G) in an oxidizing atmosphere at 300 to 600 ° C and in particular 400 to 550 ° C for a period of 1 to 6 h and in particular 1 to 5 h burned
  and
• (I) the catalyst obtained is activated in a reducing atmosphere, in particular a hydrogen atmosphere, at 350 to 600 ° C. for a period of 1 to 6 hours.

6. The method according to claim 5, characterized, that γ-alumina and / or η-alumina as a carrier in Step (A) can be used. 7. The method according to claim 5 or 6, characterized, that the alumina in step (A) has a specific upper area of 100 to 500 m² / g and preferably 150 to 250 m² having. 8. The method according to claims 5 to 7, characterized, that the alumina in step (A) has a pore volume of 0.3 to 1.0 ml / g and preferably 0.4 to 0.7 ml / g. 9. Use of the catalysts according to claims 1 to 4 for Manufacture of high octane gasolines by naphtha Reforming and / or for dehydration, dehydrating ring cleavage and / or isomerization of naphthenes and paraffi nen, especially in fixed bed reactors.