DE1271871B - Process for the catalytic hydrocracking of a nitrogenous petroleum-hydrocarbon feed - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

Clog

German class: 23 b -1/04

Number:
File number:
Registration date:
Display day:

P 12 71 871.7-44 (U 7869)

March 16, 1961

4th July 1968

The invention relates to a method for the catalytic hydrocracking of naturally occurring ones Nitrogen compounds contaminated petroleum hydrocarbon feed, namely one such feed whose boiling range is above 318 ° C and at least predominantly above 338 ° C whose nitrogen impurities are particularly harmful to the hydrocracking catalyst.

According to the German Auslegeschrift 1 072 341, a nitrogenous petroleum distillate is refined of a low octane number with the formation of a gasoline with a relatively high octane number in that the distillate together with a hydrogen-rich gas over a catalyst a hydrogenation-dehydrogenation component on an active cracking catalyst support to an isomerization cracking zone at a temperature of 315 to 455 ° C, a pressure of at least 42 at and one Space velocity between 0.5 and 15 is performed, from the products of this zone an essentially ammonia-free hydrogen-free gas stream and a product gasoline fraction of proportionately recovered high oc number and the gas stream is returned to the isomerization cracking zone. Around To obtain optimal benefits, it is considered appropriate to use a cycle oil in a boiling range between about 125 and 400 ° C and a content of about 3 to 5 ppm nitrogen to be used. From the numerical data in the publication it follows that with a nitrogen content of the fresh Catalytic cycle oil feed of 50 ppm the largest increase in conversion per Operation is achieved.

For the upgrading of a light catalytic circulating oil with a nitrogen content of 600 ppm and a boiling range of 220 to 283 ° C, Auslegeschrift 1 072 341 describes a two-stage process in which the nitrogen content of the feed is initially determined by hydrofining with excess hydrogen in the presence of a metal from the group VI and an iron group metal of Group VIII of the Periodic Table on an inert, refractory metal oxide support containing hydrorefining catalyst, the material obtained is fractionated to remove hydrogen sulfide and ammonia gas and the ammonia-free hydrocarbon feed in the presence of hydrogen at elevated temperature under pressure on a metal of the group VIII of the Periodic Table on an acidic hydrocracking catalyst containing an active support as a cracking catalyst in lower-boiling, nor-process for catalytic hydrocracking
a nitrogenous one
Petroleum hydrocarbon feed

Applicant:

Universal Oil Products Company,
Des Piaines, JIl. (V. St. A.)

Representative:

Dr. HH Willrath, patent attorney,
6200 Wiesbaden, Hildastr. 18th

Named as inventor:
Charles Henry Watkins,

Arlington Heights, JIl. (V. St. A.)

Claimed priority:
V. St. ν. America of March 16, 1960 (15 301)

Sometimes liquid products are converted. The hydro-refined, the catalytic hydrocracking In this case, the circulating oil supplied contains 100 ppm nitrogen.

This two-step process was obviously unsatisfactory because it came from the same source the proposal to further improve the catalytic conversion of normally liquid, Hydrocarbons containing nitrogen compounds, especially with regard to elongation the effective catalyst durability at a relatively low temperature to achieve that there is a special one between the first hydro refining stage and the final hydrocracking stages Treatment stage incorporated (see German Auslegeschrift 1131 346). This particular level of treatment is that at least a portion of the normally liquid hydro-refined product in an intermediate zone with a silicon-containing cracking catalyst at temperatures below those in which a cracking of the product takes place, is brought into contact.

The invention has set itself the task of a method for catalytic Hydrocracking of a petroleum hydrocarbon feed containing harmful nitrogen compounds with a boiling range above 318 ° C and at least predominantly above 338 ° C, like white oil with a boiling range of 336 to 468 ° C

809 568/496

3 4

or a mixture of light and heavier carriers, especially when they are with a metal, Vacuum gas oils with boiling range from 318 to metal oxide or a metal compound of 532 ° C, in known two-stage handling group VI, such as tungsten oxide or chromium oxide, curtain with catalytic hydrorefining and catalyzed, preferably molybdenum, in a form of molybdate table hydrockracking which are now combined by 5 or thiomolybdate and as refractory Ammonia-free hydrocarbon feed carrier zirconium oxide, magnesia, titanium oxide, kieselohne the above-mentioned intermediate treatment acid, cerium oxide, thorium oxide and preferably clay a silicon-containing catalyst in an intermediate or a mixture of toning agents with a zirconium zone the conversion to lower boiling oydx or magnesia included. The preferred liquid hydrocarbon products, despite the use of catalysts, contain 2 to about 30, in particular nitrogen sensitive hydrocracking catalysts at about 5 to about 20% iron group metal and 1 to mild working conditions while maintaining about 20% molybdenum metal or molybdenum compound hydrocracking activity of the catalyst over the elimination of refractory metal oxide, extended periods of time without reactivation and without the temperature It is necessary to gradually increase the temperature, preferably at 343 to about 427 ° C, and to carry out water. The invention is based on a substance with a pressure of about 34 to about catalytic hydrofining pretreatment with water 204 at, preferably from about 68 to about 136 at, excess oxygen passed at a temperature between 315. The speed is particularly important, and 482 ° C under a pressure in the region of 34 at which the feed is passed over the catalyst up to 204 ° C. ao will, d. H. the residence time on the catalyst. This The above-mentioned object is according to the is the conversion of nitrogen compounds into Invention achieved in that the ammonia normally achieve, in what form the nitrogen liquid hydrocarbon fraction of the hydro refining easily from the hydro refined product as being light Product with a nitrogen content of less than recoverable gas can be removed to a 1 ppm immediately after ammonia removal in 25 liquid space velocity of no more than the 2.0 volumes of feed per volume of catalyst at a temperature between 260 and 538 ° C under a pressure in the range of 34 to 204 atmospheres per hour, preferably less than 1.5 and occurring Hydrockracking is introduced. Advance up to about 0.5 to result. The ammonia dissolves preferably, that from the nitrogen-free petroleum is partly in the liquid portion of the treated hydrocarbon feed through the hydro refinery 30 feed and is partly contained in the normally liquid feed gas obtained from hydrogenation.

kung fraction with less than 1 part by weight Da of the Kataje used in the hydrocracking stage Million decreased nitrogen content of the hydrolyzer contains ingredients that work against nitrogen cracking are sensitive to a palladium or nickel on a bonds, had to be annealed in the usual way Carriers of silica and alumina are used to compensate for the loss of catalyst-holding agents Hydrocracking catalyst in the presence of activity during hydrocracking the treatment up to 534 normal liters of hydrogen per liter of the flow conditions made progressively more severe, d. H. sigen hydrocarbon content at a temperature, the temperature and / or the pressure increases and the between 315 and 427 ° C. Residence time on the catalyst can be increased to

Since in the known two-step process, a 40 to compensate for this loss. Although those among the

Charge with 100 ppm nitrogen used and stricter conditions converted amount

in the one-stage process 3 to 4 ppm nitrogen as feed rises, the proportion of un-

were viewed particularly favorably, there were no desirable light, gaseous constituents in the

look that the lengthening of the effective product increases, the higher the conversion rate.

the same catalyst durability in the case of hydrocracking, and the proportion of desired, normal

reactions at a relatively low temperature wise liquid components in the product is dem-

instead of engaging a special handset, it is considerably reduced. If you have a

could be achieved by the fact that the feed used previously according to the invention

Nitrogen content of the hydro refining product based on a total nitrogen content of no more

less than 1 ppm is decreased. Further, a 50 has been refined as 1 ppm hydro, the hydro

A particular advantage is that it is at a high value according to the cracking activity of the catalyst

the invention is possible to keep from particularly high boiling under mild working conditions, and the

the petroleum hydrocarbon feeds with high conversion of valuable, normally liquid

Nitrogen content in long operating periods. Product is at a height above 80%

Hold oden without interruption to regenerate the 55. Furthermore, the hydrocracking catalyst can over

Catalyst valuable gasoline products in long periods of time without reactivation and without increasing

to get loot. of the temperature, the pressure and / or the

For the process of the invention, the dwell time of the feed on the catalyst is

raw materials feed from the middle distillate boiling point. The hydrocracking catalyst contains

range and above, such as luminous oil fractions, gas oil 60 a hydrogenating component and a cracking component

fractions, lubricating oils and white oils, high boiling points in a uniform mixture.

Residues from fractionation towers, of catalytic one of the preferred acidic catalyst supports as

Crackers, so-called heavy cycle oils, the cracking component is a mixture of 5 to 20%

Fuel oils and other hydrocarbon materials Silica with a refractory metal oxide such as

low market value of high boiling point, the 65 alumina, zirconium oxide, magnesia, thorium oxide or

Contain pyrroles, amines or indoles, into consideration. Ceria, especially a mass of silica and

Suitable catalysts for hydro refining alumina, which together as gel oxides from their alumina

are iron group metals are precipitated as oxides or sulfides on salts. Another suitable, pissed off

active carrier consists of alumina or zirconium oxide with a non-volatile metal halide, z. B. a portion of the carrier in the form of its halide salt. The hydrogenation component can also dem Carrier in the form of a halide can be added. For example, if the hydrogenation component is platinum or palladium, the latter can be combined with the support in the form of a platinum or palladium chloride will. Other platinum group metals such as ruthenium, rhodium, iridium and osmium can also be used in amounts of preferably about 0.01 to about 1 percent by weight are combined with the carrier in the form of the metal itself or as its oxide or sulfide. Iron, cobalt and nickel are also suitable as free metals or Oxides or sulfides, also mixtures of one or more metals, such as a mixture of nickel and Cobalt.

If an iron group metal is used, the catalyst should preferably also be 0.1 to about Contains 10 percent by weight of molybdenum as free metal, oxide or as molybdate or thiomolybdate.

example

In the following series of runs, a gas oil feed was found with the properties listed below and a high nitrogen content under various reaction conditions and at different Severity levels hydrorefined to differentiate the nitrogen content of the treated mass To reduce heights, and then subjected to hydrocracking to reduce the influence of the diminution the nitrogen content of the starting mass

25th

30th

determine the life and activity of the hydrocracking catalyst. The nitrogen content of the hydro-refined mass was gradually reduced in order to clearly indicate the value of the nitrogen content at which hydrocracking becomes ineffective. The feed consisted of a mixture of light and heavy vacuum gas oils that are obtained from Wyoming- and West Texas crudes to those given in Table I below Eigenschäften in which Hydroraffinierstufe over a catalyst from 2,2 ⁰ Zo nickel and 6, 5% molybdenum was passed on annealed alumina.

Table I.
Properties of the vacuum gas oil blend

Specific gravity at 15.6 ° C 0.9440

Initial boiling point in ° C 318

10% over 415

30% over 459

50% over 487

70% over 517

90% over 526

Final boiling point in ° C 532

Total nitrogen in ppm 1810

Basic nitrogen in parts per million 625

The mixed gas oil feed was sent to the hydrorefining downstream through a reaction tube led, which is filled with the catalyst and from a salt bath of the desired conversion temperature was surrounded (see Table II below). The reaction conditions and properties of the product are listed below:

Table II

Hydro refining of gas oil mixtures under various conditions and using a nickel-molybdenum-alumina catalyst

2 Attempt no. 4th 5 1 399 3 399 399 399 204 399 170 204 102 890 102 89 890 890 1.0 890 0.25 0.25 1.0 199 0.25 151 143 196 357 160 337 333 354 11 343 0.9 0.2 108 98.5 5.3 98.5 98 99 99

Temperature in ⁰ C

Pressure in at

Hydrogen flow rate in 1/1

Liquid space velocity per hour

Properties of the liquid product

Beginning Kp. in ° C

End-Kp. in ° C

Nitrogen content in ppm

Yield of liquid product in% C ₅ +

It should be noted that the nitrogen content can be reduced to zero in hydrofinishing, without sacrificing any of the yield of the liquid product and the nitrogen content of the product depends on the severity of the hydro refining. For example, the nitrogen content of the Product to less than 1 ppm by hydrofining pretreatment at 399 ° C by either reducing the hydrogen pressure or increase the residence time of the feed on the catalyst during the conversion. The alternately Interchangeability of space velocity and reaction pressure and the resulting Reduction in nitrogen content is also illuminated by the fact that a product formed with 10 ppm residual nitrogen at 102 atmospheres pressure and at a space velocity of 0.5 can be. The product is essentially similar to what you get under one Maintains a pressure of 204 atm at a space velocity of 1.0.

With the same feed as in the previous runs, the influence of the hydrofining temperature is found on the nitrogen content of the product while maintaining the pressure (204 at) and the space velocity (1.0) at practically constant reaction conditions according to the following Table III.

Table ΙΠ

Influence of temperature on nitrogen removal from gas oil with 1680 ppm nitrogen at constant pressure and constant space velocity on a nickel-molybdenum-alumina catalyst

6th ^7th Attempt no.
8th 9 10 Temperature in ° C 329 343 371
204
0.5
534 399 427 Pressure in at 380 209 140 10 __ Space velocity Hydrogen flow rate
in normal liters / l 1 Properties of the liquid product
Total nitrogen in ppm

The ammonia formed by the hydraulic refining of the gas oil charge under the specified conditions was removed from the liquid product by bubbling through an inert gas at about 30 ^° C. until the gas stream exiting was free of ammonia. Various inert gases such as hydrogen, methane, and carbon monoxide were tested and each was found to remove ammonia to a satisfactory degree. The liquid product was free of ammonia after bubbling hydrogen through it for 15 to 20 minutes at room temperature.

Each hydro-refined gas oil product of the run was after removal of the ammonia with hydrogen at overpressure on a hydrocracking catalyst, which is more effective on the basis of tests Catalyst was selected. It is a cracking catalyst made from a calcined mixture of 63% alumina and 37% by weight Silica, impregnated with a palladium salt and then calcined, so that the catalyst is 0.4% Contained palladium. The catalyst was placed in a vertical reaction tube in an upright position Reaction temperature maintained salt bath used. The same reaction conditions were used in each experiment adjusted to the effect of the nitrogen content of the feed on the degree of conversion to investigate. The reaction temperature was maintained at 357 ° C and the hydro refined Gas oil was fed at a liquid space velocity of 1.5 parts by volume of liquid feed each Volume catalyst passed through per hour, and hydrogen was together simultaneously in the Ratio of 267 normal liters / l of feed introduced below 204 at. The products were from the head removed, and in a high-pressure separator, the gas portion at the reaction pressure was from the liquid Share separated. The latter was fed into a distillation column that worked under atmospheric pressure and wherein the light, below isopentane (about 30 ° C) boiling gases from the remaining liquid product were distilled off. The residue was then distilled to obtain a fraction with a final boiling point to be separated from 204 ° C, on which the percentage conversion and the evaluation of the Loading were related. The following table IV shows the observed values.

Table IV
Hydrocracking of hydro refined gas oils, influence of nitrogen content on feed

1 2 feed
Attempt no.
3 4th 5 Nitrogen content in ppm. 108
10 11
24 5.3
30th 0.9
100 0.2
100 Conversion period
Hours in the stream - ² )
0 - ² )
28 75
41 75
67 76
74 Conversion ¹ ) at the beginning of the run
Conversion ¹ ) at the end of the period ...

*) Conversion is measured by the volume percent of the feed mass, which is converted into liquid product from the gasoline boiling point.

range (21 ° C initial to 204 ° C final boiling point). ² ) Catalyst activity fell too quickly to allow conversion to be measured.

It can be seen that as the nitrogen content of the hydrorefine feed increases, hydrocracking occurs drops rapidly over time. So at 180 ppm the catalyst was quickly deactivated, and he did not retain activity long enough to have a measurement of conversion to product 204 ° C end point to be able to measure. At 5.3 ppm nitrogen, the catalyst was also deactivated rapidly. Although the catalyst was capable of 75 Vo of the feed in the initial period mass to convert to a 204 ° C endpoint product was activity after only 30 hours dropped to a level where the catalyst was only 41% of the feed to product from Endpoint would convert 204 ° C. Even if the nitrogen level is reduced to only 0.9 ppm the activity gradually fell from the original 75% to 67% over 100 hours. However, if the nitrogen content of the hydro refined feed was reduced to 0.2 ppm,

it fell only slowly over a period of 100 hours of operation to 74% compared to 76% at the beginning away. These results clearly demonstrate the adverse effect of nitrogen pollution of the feed on the hydrocracking activity of the catalyst and clearly show the suitability the removal of the nitrogen contamination from the feed to the fullest possible extent.

Following each of the above treatment periods, the temperature was increased by the activity of the hydrocracking catalyst to the initial value of 75%. When loading with 108 ppm nitrogen it was necessary to raise the transition temperature to 399 ° C, and the Activity again fell rapidly with continued use of a feed with the above nitrogen content. With the feed adequately refined to a nitrogen content of only 0.2 ppm the activity of the catalyst was increased to a value of 76% after 100 hours in the flow of 74% ao only increased by the fact that the temperature was increased by an additional 5.8 ° C.

Other hydrocracking catalysts, e.g. B. with cobalt and / or nickel or their sulfides in combination with molybdenum on a silica-alumina carrier or a catalyst made from a platinum group metal, such as palladium on alumina with bound halogen, e.g. B. fluorine and / or chlorine, show the same sensitivity to nitrogenous Compounds in the feedstock added to the hydrocracking process. In any case it was it is necessary to raise the conversion temperature of the hydrocracking reaction to a level at that an excess of gaseous products was formed when the catalyst was used during the hydrocracking process remained in the stream.

Claims (2)

Patent claims: 1. A process for the catalytic hydrocracking of a petroleum hydrocarbon feed contaminated with naturally occurring nitrogen compounds which are harmful to the hydrocracking catalyst and having a boiling range above 318 ° C and at least predominantly above 338 ° C, in which the nitrogen content of the feed is initially obtained by hydrofining with excess hydrogen at a temperature between 315 and 482 ° C under a pressure in the range from 34 to 204 at in the presence of a metal of Group VI and an iron group metal of Group VIII of the Periodic Table on an inert, refractory metal oxide support containing hydrorefining catalyst, which frees the refined hydrocarbon feed from ammonia, and the ammonia-free hydrocarbon feed in the presence of hydrogen at elevated temperature under pressure on a Group VIII metal on an acidic cracking catalyst door Ager-containing hydrocracking catalyst is converted into lower-boiling, normally liquid products, characterized in that the normally liquid hydrocarbon content of the hydrofinishing product with a nitrogen content of less than 1 ppm immediately after the ammonia removal is at a temperature between 260 and 538 ⁰ C under a pressure in the range hydrocracking is introduced from 34 to 204 atm. 2. The method according to claim 1, characterized in that from the nitrogen-free Petroleum hydrocarbon feed obtained from hydro refining, normally liquid Feed portion with the nitrogen content reduced to less than 1 part per million by weight hydrocracking on a palladium or nickel on an annealed support of silica and alumina containing hydrocracking catalyst in the presence of 89 to 534 normal liters of hydrogen per liter of the liquid hydrocarbon content at one temperature between 315 and 427 ° C. Considered publications: German Patent No. 933 826; German interpretative document No. 1 072 341; British Patent Nos. 798 395, 781 706; Italian Patent No. 386 026; U.S. Patents Nos. 2,585,337, 2,619,450, 676,907, 2,715,603, 2,734,019, 2,846,356,
882 221; Chemisches Zentralblatt, 1943, I, pp. 356/57. A priority document was displayed when the registration was announced. 809 568/496 6.68 © Bundesdruckerei Berlin