DE1156533B - Process for hydroforming raw gasoline - Google Patents

Description

Two types of hydroforming are known, hydroforming with quiescent bed and hydroforming are referred to as fluidized beds. In the former method, this is usually done with hydrogen-rich gas mixed raw gasoline sequentially through a series or group of Reaction chambers passed, the reaction mixture being heated again each time before entering a reaction chamber. Usually three or four reaction spaces working in series are used and the process is carried out carried out regeneratively, semi-regeneratively or non-regeneratively. The hydroforming process with fluidized beds has only one reaction space, and the finely divided catalyst particles are required to circulate Maintain reaction space and regenerator. The method of the invention can be used both use for hydroforming processes with quiescent bed as well as for those with fluidized bed.

When reforming under normal conditions, coke is formed, which is uneconomical to produce and is harmful in that it lowers the yield of valuable products and affects the Catalyst particles settle, making them less active and therefore requires regeneration. In the normal Hydroforming process is hydrogen or hydrogen-rich recycle or in the reaction Process gas is added to reduce this build-up of coke on the catalyst. These Hydrogenated olefins are for the most part gaseous and there is a significant loss of liquid products occurs when the product is later separated from the light gases.

It has now been found that higher yields of a gasoline with a higher octane number can be achieved if a crude gasoline in the presence of added butane from the boiling range between 60 and 204 ° C with hydrogen in the presence of an alumina-platinum catalyst at 455 to 595 ° C and hydroformed to a total pressure of 21 to 57.8 atmospheres, the chlorine content of the catalyst being kept at about 0.3 percent by weight and, instead of hydrogen, additionally so much butane being added that the hydrogen partial pressure is between 10.5 and 24.9 kg / cm ² is, while the hydrocarbon partial pressure of the butane plus the hydroforming gasoline is higher. The addition of the butane results in a type of alkylation in which the butane reacts with the olefins formed during the reaction. Instead of the formation of light gases by hydrogenation of these olefins and the resulting lower yield, the processes are used for hydroforming
of raw gasoline

Applicant:

Esso Research and Engineering Company,
Elizabeth, NJ (V. St. A.)

Representative: Dr. W. Beil, A. Hoeppener
and Dr. HJ Wolff, lawyers,
Frankfurt / M.-Höchst, Antoniterstr. 36

Roger M. Butler, Sarnia,

and John A. Bichard, Point Edward (Canada),

have been named as inventors

Olefins alkylated by the butanes and the yields of liquid products and their quality improved.

In the present invention, alkylation takes place simultaneously during the hydroforming reaction of olefins instead, which is achieved by the fact that the amount of hydrogen in relation to the hydrocarbon is limited, with the shortage of hydrogen by a corresponding amount of butane is replaced. In the process according to the invention, the hydrogen partial pressure is kept very low compared to the butane and hydrocarbon partial pressure; In addition, care must be taken that a lower chlorine content is maintained in the platinum-aluminum catalyst used than is usual in normal hydroforming reactions. Through this specific way of working, namely that between the butane or isobutane and the olefins which are formed during the hydroforming reaction be formed, a reaction takes place, an additional amount of liquid becomes Obtained hydrocarbons.

It has already been described in the literature to add butane to hydroforming, however, this addition did not serve to react with those formed during hydroforming

309 730/310

Olefins. This mode of operation has only been made possible by the present method, in which in addition to the ratio of hydrogen to hydrocarbon, the type of catalyst and the Chlorine levels in the catalyst are critical.

The procedure according to the process according to the invention also differs from the usual one Recirculation of gaseous hydrocarbons in the hydroforming zone, as this is essential larger amounts of butane or isobutane are added than would be required during a normal hydroforming process happens. The reaction chambers can either be those with quiescent beds or those with a moving bed or fluidized bed be. According to the invention, a group or a series of reaction spaces can also be used Quiescent bed can be used, each with an oven for reheating between the reaction chambers are built in.

The drawing shows a scheme of the process in which a hydroflnated via line 2 Raw gasoline fraction with a boiling point between 60 and 204 ° C is fed. At the same time be over a line 4 hydrogen or hydrogen-rich recycle gas and via a line 5 butane into the line 2 initiated. The mixture flows through line 2 into furnace 3, where it is heated to about 540 ° C will.

The heated mixture passes from the furnace 3 through the line 6 into the reaction chamber 7, in which it is with comes into contact with a quiescent bed of an alumina-platinum catalyst. The in the reaction chamber 7 The prevailing temperature, pressure and other working conditions are set so that the Hydroforming is guaranteed.

The hydroformed mixture leaves the reaction space 7 via line 8 and is in the device 9 cooled and partially condensed. The hydroformat passes from the cooler 9 via the line 10 in the separator 11, where the hydrogen-containing gas, which escapes overhead, from the remaining Mixture or liquid product is deposited. The hydrogen-containing gas leaves the separator via line 12 and is via line 13, line 4 and circulation pump 14 in the line 2 returned. Excess hydrogen-containing treatment gas is by means of the Line 15 withdrawn.

The liquid product in the separator 11 flows via the line 16 to the depropanizing device 17, in which the propane and the lighter substances are drawn off as the top fraction by means of line 19. The liquid product remaining in the depropanizing device 17 flows through the line 18 in the debutanizing device 20. In this, the butane is separated and, if necessary, via the Lines 21 and 5 and the circulation pump 22 are fed back into line 2. With the line 23 can fresh butane can be added or withdrawn. The debutanized liquid product leaves the debutanizer 20 down through line 24.

It will be understood that butane circulation is not a necessary feature of the invention and that butane used does not need to be separated from the end product.

The; Hydroforming conditions are in the following Table compiled:

area to 595 Preferred Temperature, ⁰ C ... 455 up to 70 485 to 595 Pressure, atü 14th 21 to 42 Loading speed, until 10 Weight / hour / weight ... I. 2 to 6 Hydrogen circulation speed, to 214.2 1000 l / hl 17.9 so much that one Partial pressure from 10.5 to 24.9 kg / cm ² arises Butane speed speed, 10001 / hl (Ge velvet loading of the reaction to 214.2 vessel) 17.9 sufficient, to the Ab fallbutane in the refiner plant on to 5355 to need Butane consumption, l / hl until

A raw gasoline fraction that boils between 60 and 204 ° C is used as the starting product. she can from unprocessed, cracked or paraffirüschem Consist of raw gasoline. At least one starting product which is hydrofined is preferably used the sulfur content of the feed should be kept low enough that the platinum catalyst does not interfere will.

The catalyst consists of platinum on acid alumina as a carrier. The level of acidity of the carrier is about 0.3 percent by weight chlorine, based on the total catalyst. In normal In hydroforming processes, a catalyst is usually used that is 0.001 to 2.0 percent by weight Contains platinum and 0.5 to 1.5 percent by weight chlorine, the remainder being an adsorbent alumina finishing agent consists. The amount of chlorine from 0.5 to 1.5 percent by weight is the chlorine content at the usual use of platinum hydrochloric acid in the preparation of the catalyst. A catalyst that has already been used in a hydroforming process is part of it has lost its chlorine content and its chlorine content is now in the required range extremely well suited for the process according to the invention. The catalyst can according to known Process can be produced, but when using it, the acidity must be within the specified range.

example 1

A starting product of 50% cyclohexane and 50% normal heptane was made under normal hydroforming conditions hydroforms at a ratio of about 116.025 l / hl hydrogen and one Previously used hydroforming platinum-alumina catalyst, the 0.6 percent by weight platinum and 0.6 contained up to 1.0 percent by weight of chlorine. The catalyst

Sator had previously been used in hydroforming processes and its chlorine content was prior to use has been reduced so far in this experiment that the actual chlorine content is about 0.3 percent by weight fraud.

Temperature, ⁰ C

Pressure, kg / cm ²

Feed rate, wt / hour / wt. ..

Hydrogen velocity, l / hl

Isobutane velocity,
l / hl

Hydrogen partial pressure,
kg / cm ²

Isobutane partial pressure,
kg / cm ²

C ₅₊ yield, weight percent

Yield of aromatic
Links,
Weight percent

Research octane number (unleaded)

Butane consumption, weight percent

Hydrogen alone

485 31.5

2.18 116.025

0 25.4

0.14 88.6

44.8

84.6

-3.9 *

Hydrogen + butane

485 31.5

2.18 42.840 48.192 11.5 14.8 97.6

64.4 92.6 14.1

* Butanes were produced at 3.9 percent by weight of the raw gasoline charge.

The above example shows the results obtained when some of the hydrogen is replaced with isobutane. From the fact that an amount of butane equal to 14% by weight of the raw gasoline feed was consumed and that a very high yield of C ₅ + hydrocarbons was achieved, it is evident that alkylation has taken place. Experience with this example shows that by reducing the hydrogen rate and adding isobutane to the hydroforming charge, greater yields of liquid products and a higher octane product are obtained. The addition of isobutane according to the present invention gave a 97.6 weight percent yield with a research octane number (unleaded) of 92.6 compared to an 86.6 weight percent yield with an octane number (unleaded) of 84.6 when hydroforming in the conventional manner .

ao The butane added in the process can either be normal butane, isobutane, or a mixture of both. This is shown in the next example.

Example 2

The same starting product as in Example 1 was made using a 0.6 percent by weight platinum catalyst hydroformed. The catalyst originally contained 0.6 percent by weight chlorine, this content had been reduced to an actual chlorine content of about 0.3 weight percent. While During the experiment, no chlorine treatment was used to raise the chlorine content.

attempt All in all H ₂ Pressure atü iC ₄ No. 32.5 26.2 0 1 57.4 23.1 21.4 2 57.8 24.9 I.
I. 0 3 I.

nC ₄

₊ Yield
LV ¹ Vo

Octane number
(unleaded)

21.2

84.2
90.0
90.5

84.0
86.2
85.8

The hydrogen partial pressures were generated for all 45 and in the past 90 working hours

these attempts same. Has been treated with isobutane and with chlorine three times and now refused

paint butane are about the same advantageous chlorine content of about 1 to 2 percent by weight

Results have been achieved. on. The following results were achieved:

Example 3

A hydrogen feed containing 50% cyclohexane and 50% normal heptane was fed under normal Hydroforming conditions (485 ° C and 31.5 atmospheres) hydroformed. The catalyst persisted each test made from 0.6 weight percent platinum-alumina; however, the condition of the catalyst was different with each attempt. The results obtained in Example 1 where a spent platinum-alumina catalyst was used (here called Catalyst A and having a chlorine content of 0.4 weight percent) were used with the results compared that with a fresh catalyst and a catalyst treated with chlorine, which had a higher chlorine content than the catalyst of Example 1 were achieved.

Catalyst B was a fresh platinum-alumina catalyst that was about 0.6 percent by weight Contained chlorine; Catalyst C was brisk

50 Hydrogen circulation speed 1 A. catalyst C. capacity, 1000 l / hl B. 55 isobutane velocity, 42.84 33.92 1000 l / hl 62.48 Loading speed 48.20 42.84 speed, weight / weight / hour, 42.84 C ₅₊ product ⁶⁰ octane number (unleaded) .... 2.18 2.00 C ₅₊ volume percent 92.6 2.07 83.2 C ₊ weight percent 90.9 93.3 77.1 Butane consumption, weight 97.6 80.6 81.2 65 percent 87.0 14.1 4th 11.0

In these comparative tests, the unexpected and unpredictable results were again obtained

clearly achieved when using a catalyst with limited chlorine content. Using of the catalyst A there was an increased alkylation, as from the increased butane consumption emerges. According to the invention, by using catalyst A, a yield was achieved which 10 to 16 percent by weight was higher than the other examined catalysts and an octane number (unleaded) comparable to that obtained with fresh Catalyst B and that obtained with Catalyst C scored is far superior.

During hydroforming, the chlorine content in the platinum catalyst has two effects. Which is an effect advantageous because it increases the activity of the catalyst, while the second is bad because it increases the activity of the catalyst Deactivation rate of the catalyst increased. Example 4 shows this.

Example 4

The 0.6 percent by weight platinum catalyst used in this experiment had been pretreated in such a way that that it contained different amounts of chlorine. The catalyst of experiment 1 was previously at 2 percent by weight Treated with chlorine and therefore had the highest chlorine content at the time of the experiment. the Catalysts of experiments 2 and 3 were treated with steam in such a way that from the Catalyst of experiment 2 a large part of the chlorine and from the catalyst of experiment 3 all of it Chlorine was removed. The feed consisted of hydrofined raw gasoline with a boiling point between 4 and 165 ° C. The feed rate was 1.5 w / w / h. and the hydrogen circulation rate 10 710 l / hl.

Attempt no.
2

Catalyst pretreatment

Average activity

Temperature, ⁰ C

C ₅₊ yield LV% at an octane number of 99

Relative deactivation speed

2 percent by weight Cl ₂

30 501

68.5 high weak treatment
of the stream

15th
516

73.2
middle

strong treatment of electricity

17th

527

71 low

If the chlorine content is reduced according to the invention, the speed of the catalyst is reduced this also results in - as the last example shows - and therefore higher temperatures at lower temperatures game can be seen - the advantage that the deactivation disadvantageous effects are possible.

Example 5

In this experiment, the same weight percent loading has been reduced, and no treatment of the catalyst and 2 was used during and the same catalyst as in Examples 1 experiment. The chlorine content of the catalyst with chlorine. The pressure was kept at 31.5 kg / cm ² to an actual level of about 0.3.

temperature
⁰ C Recycle gas
1000 IM Butane addition
1000 l / hl hydrogen
kg / cmä Volume percentage
liquid usboot
Weight
percent Octane number
(unleaded) 471
485
494 46.41
57.34
69.62 37.49
41.06
42.84 12.6
12.9
14.4 78.9
80.0
78.7 83.5
86.3
85.5 87.5
92.5
97.9

This experiment shows that at temperatures of 485 ° C. and more, the yield of valuable end product and the octane number can be increased.

The invention thus shows an improved process for hydroforming in the presence of Butanes. The improvement consists in regulating the chlorine content of the platinum-alumina catalyst. Limiting the chlorine content results in unexpected and unpredictable results, which result in better yields, products with a higher octane number and lower catalyst deactivation show at higher temperatures.

Claims (3)

Claims: 1. A process for the hydroforming of raw gasoline boiling range between 60 and 204 ° C with hydrogen in the presence of an alumina-platinum catalyst at 455 to 595 ° C and a total pressure of 21 to 57.8 aiii, characterized in that the Keeps the chlorine content of the catalyst at about 0.3 percent by weight and, instead of hydrogen, additionally supplies so much butane that the hydrogen ^{partial pressure is between 10.5 and 24.9 kg / cm 2} , while the hydrocarbon partial pressure of the butane plus of the raw gasoline subjected to hydroforming is higher. 2. The method according to claim 1, characterized in that the ratio of the hydrogen partial pressure at which butane partial pressure is maintained between about 164: 212 and 355: 303. 3. The method according to claim 1, characterized in that the volume of the supplied 10 Butane is at least about the same as that of hydrogen. Considered publications: French Patent Nos. 1108 002, 1132042;
Chemisches Zentralblatt, 1952, pp. 4082, 4083. 1 sheet of drawings