DD144789A1 - METHOD FOR THE CATALYTIC REFORMATION OF HYDROCARBON MIXTURES - Google Patents

Abstract

The invention relates to a method for catalytic Reforming of hydrocarbon mixtures for the production of aromatic and high octane carburettor fuel components to 'bioder polymetallhaltigen catalysts with the aim of a constant high turnover and a consistently high yield of target products to reach. According to the invention, the goal is achieved in that the Process at temperatures of 723 to 833 K, a pressure of 0.49 to 1.96 MPa, a load of 1 to 4 v / vh and a Hydrogen / carbon black to water ratio of 4.5 to 10 moles / mole in the presence of a catalyst consisting of metals and / or their Compounds of the 8th subgroup of ΡΞΕ in combination with metals and / or their compounds the ö..und 7 '. Subgroup and the 4. Main group in connection with AlumoSilikaten or Aluminosilicate Al 2 O 3 mixtures or fluorinated Alumina is carried out, wherein the catalyst, basic Nitrogen compounds, such as amines or ammonia, before Reaktiorisbeginn and / or during the operating period in such an amount be that a ^ constant Aktxvitätszustand the catalyst is achieved.

Description

A process for catalytic reforming of coal hydrogen mixtures

C 10 G 35/04

Field of application of the invention

The invention relates to a process for the catalytic reforming of hydrocarbon mixtures for the production of aromatic hydrocarbons and high-octane gasoline fuel components on bi- or poly-metallic catalysts.

Characteristic of the known technical solutions

Processes for the preparation of aromatic hydrocarbons and high octane carburettor kraft component by heterogeneous catalytic conversion of hydrocarbon mixtures are known and have proven themselves on an industrial scale (DOS 2 443 976, DOS 2,527,972, DOS 2,534,905, US-P 3,940,329, US-P 3,956,107, PR-PS 2,160,269, Barbier, J.C., Berthelin, M., Jonchere, J.P., et al., IPP, Prank, et al.).

In catalytic reforming, hydrorefined gasoline fractions are obtained under conventional conditions at temperatures of about 773 K and pressures of 2.94-3.5 MPa. used in modern reforming plants at temperatures of 773 838 K and pressures of 0.78-1.47 MPa on bifunctional mono-, bi- and polymetallic catalysts

The catalysts have a hydrogenation / dehydrogenation function, which are brought about by metals and / or compounds of the VIII, VI, VIIe subgroup and the PU group of the PSE.

-ζ-

The acidic (or also cracking) puncture of the catalyst is attributed to an acidic material, such as halogenated alumina. These catalysts have a balance of hydrogenation / dehydrogenation and cracking activity to produce the desired target products under the appropriate process conditions ·

In the development of the reforming process, the approach to the most favorable thermodynamic conditions has served as the fundamental objective both of the process design and of the catalyst development. In this development, the reforming process has become increasingly technically complicated and more complicated in terms of process control. Under these conditions, the following waxy parts result for the above-mentioned catalyst system:

The increased temperature level and the constant temperature increase to maintain activity level lead to increased cleavage, coke deposition on the catalyst, surface damage of the catalyst and deterioration of the acidity.

To maintain high catalyst activity and stability, the hetero-compounds present in the feedstock, such as S, IST and O compounds must be removed by hydrorefining processes. Thus, B. 3 for feedstocks for Rheniform S contents of 0.5 1 ppm (Blue, E.M., Gould, GD "Production of Aromatic Hydrocarbons by Low-Pressure Rheniforming", Oct. 21, 1975), Technical Sales Seminar in the GDR, Cecil, Rc Re, Kmak, WS and others Oil and Gas Journal, Aug. 7, 1972, 50-53) and nitrogen contents of 0.5-1 ppm (Oil and Gas Journal, March 26, 1973, 83-92). As an acceptable H ₂ O content, values of 10 to 15 ppm are required in the starting material (DOS 2 047 873, DOS 1 770 412, Oil and Gas Journal, March 15, 1971, 62-68 ) »-

- During the operating periods, the presence of traces of water leads to Haiogenaustrag and thus to the reduction of the catalyst activity (Hydrocarbon Processing, Febr · 1971, 89-94) * In the simultaneous presence of nitrogen compounds there is formation of NH ^ Cl-ITiederschläge in the reactor and the downstream equipment (Oil and Gas Journal, March 26, 1973 »87-92) and corrosion problems · To compensate for the continuous loss of halogen, halogen and / or halogen compounds are added«

The catalysts must be continuously regenerated and reactivated in relatively short intervals due to the tightened process conditions in order to regain their initial activity in plague bed processes, and in moving bed processes.

These regeneration and reactivation processes (DOS 1 645 792, DOS 2 255 497, DD-PS 80 133, DD-PS 1 206 689, DD-PS 121 716, DOS 2 346 858, GB-PS 1 364 616) are complicated , time-consuming and lead under high temperature load to the catalyst damage and Katalyeatordesaktivierung (Birke, P., Engels, S · Z · Chem · 18 (1), 1977, 37-38).

Also known catalysts for hydrocarbon conversion, in addition to metal components of crystalline and. amorphous alumino silicate-ene and / or mixtures of alumino-silicates, and refractory inorganic oxides, such as _e B "exist, AIpOo as acidic components *" These types of catalysts differ öich of the Metal / AIPO, -. catalyst 'types by an altered ratio of Hydrogenation / dehydrogenation activity for cracking activity ·

In this case, metals of VIII., VII., VI. and I. Subgroup, the IV "main group and also as a single metal component or combinations of different metals on crystalline aluminosilicate and / or SiO / AlgO ^ mixtures used (DOS 1 251 892, DOS 1 217 929, DOS 2 400 448, DOS 2 162 442, DOS 1 920 546, DOS 1 76-464) · In order to increase the catalyst activity, the addition of organic nitrogen compounds is claimed (DOS 1 445 396).

Despite all advantages, such. As insensitivity to HeteroVerbindungen and HpO, low reaction temperature compared to reforming with conventional catalysts, waiving reactivation, these types of catalysts on an industrial scale in the reforming of hydrocarbon mixtures did not prevail · The causes are the extremely high cracking activity of aluminosilicate catalysts, so that When using these catalyst systems by increased coke deposition only very short periods of operation can be achieved.

Object of the invention

The aim of the invention is to find a process for catalytic reforming which makes it possible to achieve a constantly high conversion and a consistently high yield of aromatic hydrocarbons and high-octane gasoline fuel components.

Presentation of the essence of the invention

The object of the invention is to make the process for the production of aromatic hydrocarbons and hochoktanigen gasoline fuel components so that with little effort on reconstructions using existing facilities and using a catalyst in the process, which is characterized by high activity, stability and selectivity , a technologically advantageous solution is achieved

According to the invention, the conversion of hydrocarbons takes place mixtures for the production of aromatic hydrocarbons and hochoktanigen gasoline fuel components in the presence of catalysts which have a non-typical for the processes of high acidity and an unusual ratio of hydrogenation / dehydrogenation and acidity and by exposure to basic N compounds be specifically influenced to achieve high yields of target products over long periods of time by adjusting a differentiated acidity across the individual reactors ·

The catalyst for the conversion process consists of a combination of bimetal or polymetals and inorganic oxides. The hydrogenation-dehydrogenation function is accompanied by metals and / or metal oxides of the FSE metalloid and metals and / or their compounds of the VI b * transition group, optionally in Combination with metals and / or their compounds of VII b · subgroup and / or IV _e main group causes, while the acidity (or acidic) puncture on aluminosilicates and / or fluorinated aluminas is realized · This aluminosilicates have a SiO ₂ Proportion of> 60 Ma * -% and aluminum oxides having a Pluoranteil of 0.2 - 4 "Μα · .-% proved to be advantageous for achieving a high acidity of the catalysts of the invention · The aluminosilicate content in the total catalyst is in this case preferably 1-30 Ma» -%.

As a measure of the acidity of the chemisorption is JJH-by the method of dynamic KH -, - using chemisorption, which in Mol HH_ / g catalyst is indicated · The acidity of the catalysts of the invention is (3 - 8). X 10 ~ ⁵ mol KH ₃ / g support, preferably (5 - 6). mol NIL x 10 ^"5 · Präger!.

For example, amines or WH- are added to the reaction zone as basic nitrogen compounds for the purpose of selectively influencing the acidity of the catalyst. The addition takes place before the beginning of the reaction and / or during the reaction period. In technical installations, the addition of basic nitrogen compounds into the starting material and / or into the reaction mixture Hydrogen gas in front of the 1 × reactor and / or the input product stream of each reactor, the staggered addition of NH ~ having proved to be advantageous for the course of the reaction.

Use products for the process are complex hydrocarbon mixtures in the boiling range of 323-513 K, for example straight-run fractions, fractions of thermal and catalytic cracking, etc. A significant advantage of the process according to the invention is in contrast to conventional processes (DOS 2 255 497, DOS 2 360 504, US Pat. No. 2,952,611, US Pat. No. 3,447,777, US Pat. No. 3,474,026, US Pat. No. 3,649,524) disclose the reduced purity requirements of the product entering the reaction zone and the hydrogen gas or · the hydrogen-rich gas · water contents in the feedstock up to the saturation limit do not lead to a reduction in the activity of the catalysts · This makes it possible to dispense with technically complex product and gas drying equipment, as required in modern low-pressure moving bed processes. · Basic nitrogen compounds have according to the method of the invention no catalyst damaging effect. Therefore, removal of such compounds from the feedstock by hydrorefining processes is not required.

m. 7 -

With respect to sulfur, the process according to the invention is also insensitive up to the concentration of about 100 ppm in the feedstock.

The process according to the invention operates in the presence of hydrogen or hydrogen-rich gases in the temperature range of 723-833 K, a load of 1-4 v / vh, a pressure of 0.49-1.96 MPa and a hydrogen / hydrocarbon ratio of 4, 5 -. 10. mol / mol ·

embodiments Example 1

Catalysts A and B, the following composition

respectively

A B

(Data in% by mass)

Pt 0.51 0.35

Re - 0.30

SiO.sub.o proportion based on

Total catalyst 22.3 23.7

be to convert a Kohlenwasserstoffgemischos in a test pressure reactor with gas circulation under the following experimental conditions

Pressure MPa 2 _f 45

Load v / vh 3

Cycle gas / ^ ^

Prod "ratio nri.N / nr 800 j 1 is charged with an input product of the following composition (% by mass):

C _K paraffins 10.65

n-hexane 21,13

i-hexane 19,86

a ~ heptane 8.95

i-Heptane 12:25

Cg paraffins 1.43

S-content 9 ppm

cyclopentane 1.43 4.17 Methylcyclopentane 7.71 9.53 Gyclohexan 0.64 Co-Iiaphthene 1.61 Co * Haphthene 0.64 benzene toluene

- p

The catalysts were 'each with 0.48 Ma _e before the product injection - loaded% IHO (based on built-in catalyst quantity) · During the trial, was in reactors by HH - a constant dosage Mi, -. Set Uiveau "

Catalyst A B

Test time (h) 40 120 240 40 122 240 402 ..

experimental

temperature (K) 753 752 754 753 755 751 756

Yields, based on EP

Liquid-

product (wt%) 92.6 93.0 93, -8 92.1 92.0 92.2 92.3

Reaction gas (Ma, - <£) 7.4 7.0 6.0 7.2 7.8 8.0 7.8 7 ₁ 7

Benzene yield (Ma.-SO 11.4 10.9 9.4 11.7 11.9 11.9 11.5

NHL Conc. in recycle gas

(VoI, ppm) 16 14 t5 17 18 16 17

activity

characteristic number ^x; 1056 1088 938 1170 1187 1190 1150

As can be seen from the example given above, the bimetallic catalyst B achieves an approximately constant benzene yield over the entire experimental period in comparison to the monometallic catalyst A. The better performance of the catalyst B is shown by the activity index.

'Activity index: Liquid yield χ Aromatic content

in the reaction product

Example 2

The catalyst B is charged under the conditions given in Example 1 and the feedstock during the experiment with different amounts of UEL · The dependence between NHL concentration in the reaction zone (measured in the recycle gas) and the liquid yield is monitored «

catalyst B 758 758 757 Temperature (K) 16 30 HBL concentration in the recycle gas (ppm) 83.5 90.2 95.1 Liquid product (% by mass) 19.7 20.1 19.4 γΛ aromatics yield ^J Γ970 2010 1940 Activity code AKZ

based on Einsatzprcdukt

Example 3

Catalyst B and an alumina-based catalyst having a composition of 0.42 Ma "-% Pt, 1.4 Ma" -% Cl, balance AlpO- (Designation C) _s are at a pressure of 1.96 MPa , a load of 2 v / vh and a cycle gas / product ratio of 1000; 1 (nri.If./iir) charged with the feedstock mentioned in Example 1 · The feedstock of the catalyst B was to achieve a benzene content of 13 Ma. % added over the entire operating period of 1,180 hours of ethylenediamine in decreasing concentration

- 40 -

Catalysis t or

Test time (h) 200 450 800 1180 210 460 810 1180 Temperature (K) 748 754 753 755 7.63 768 776 '

lEL concert

Cycle gas.

(Ppm by volume) 42 27 22 18 - -

Flüssigaus-

prey (2fe .-? Q 87.1 91.6 92.0 91.4 89.7 88.4 87.9 87.2

Benzene content. '

(Ma.-90 12.4 13.2 13.0 13.3 13.3 t3.2 13.2 13, C

Code AKZ 1193 1210 1200 1220 1190 1167 1160 1134

With the exception of the start phase, in which the catalyst B shows its high cleavage activity despite the high NIL content in the cycle gas, the targeted addition of ethylene diamine results in a constant activity with high liquid yields over the operating period, which is above the values of the catalyst C.

Example 4

Of the catalysts used in Example 3, the carbon content was determined after completion of the long-term test.

Catalyst 3 Q

Carbon content (% by mass) 5.5. 10.3

The bimetallic aluminosilicate catalyst B, which was charged with WEL (in the form of ethylene diamine) during the operating mode, has a carbon content which is about 50 % lower. This effectively means an extension of the operating period of the catalyst.

'A4 hat

With the application of the method according to the invention, the following technical / economic advantages result over conventional methods:

Setting of a constant activity by the controlled NEL metering at a constant temperature in the reaction zone. This results in a constantly high conversion and a constant high yield during the operating period of the catalyst.

· - Improvement of aromatics formation reactions

- Improvement of isomerization reactions

Lowering of the temperature level in the reaction zone compared to conventional methods with the same performance. Thus, the application of the method according to the invention in existing reforming plants offers itself without costly reconstruction measures.

- Reduction of the split rate

«Reduced coke deposits on the catalyst. · Extension of operating periods

- Extension of the catalyst life

- Waiver of expensive drying facilities for the feedstock and the hydrogen gas

Claims (1)

- 4L- Claim of invention . 1 # Process for the catalytic reforming of hydrocarbon mixtures for the production of aromatic hydrocarbons and high octane gasoline fuel components in the presence of hydrogen-rich gases, characterized in that the process takes place at temperatures of 723-833 K, a pressure of 0.49-1.96 MPa, a load of 1-4 v / vh and a hydrogen / hydrocarbon ratio of 4.5 to 10 mol / mol in the presence of a catalyst consisting of metals and / or their compounds of the 8 · lifting group of the PSE in combination with metals and or their compounds of the 6 · and 7 · lifting group and the 4 · main group is carried out in conjunction with aluminosilicates or aluminosilicate AlpO ^ mixtures or fluorinated aluminum oxides, wherein the catalyst basic nitrogen compounds such as amines or ammonia before the reaction and / or during Operating period are metered in such an amount that a constant state of activity of the catalys ators is achieved · 2 · Method according to item 1, characterized in that the Alurno
on v / eist. the aluminosilicate has an SiO 2 content of> 60 Ma _e -9 43 - 3 Process according to items 1 and 2, characterized in that the aluminosilicate content relative to the total catalyst is 1 to 30% by mass. Process according to items 1 to 3, characterized in that the dosing of the basic nitrogen compound into the input product stream and / or the hydrogen gas takes place upstream of the 1-reactor and / or the product stream of each reactor. Process according to item 4, characterized in that the basic nitrogen compound, depending on the activity state of the catalyst, is present in the recycle gas in concentrations of 1 to 200 ppm by volume, measured as HEU.