JPH0258314B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to hydrocarbon conversion processes. More particularly, this invention relates to an improved process for the hydrogenation of olefinic and aromatic compounds. More particularly, the present invention relates to an improved method for producing jet fuels and white oils which comprises pretreating a hydrocracking catalyst with a nitrogen-containing organic compound for a period of time sufficient to suppress the cracking activity of the catalyst. , and then heat the treated catalyst to about 232.2°C to about 382.2°C (about 450°C
for use in the hydrogenation of jet fuels and white oil distillates at temperatures within the range of 720°C to about 720°C. It is already known in the industry to improve the quality of various petroleum-based products by catalytic hydrogenation. Typically, prior art catalyst systems consist of an amorphous refractory metal oxide, such as alumina, and a hydrogenation component, the hydrogenation component being a metal (or oxide or sulfide). The metals mainly used are oxides of nickel, cobalt, molybdenum and tungsten. However, these prior art methods generally use harsh conditions of temperature and pressure and/or require multiple steps. Another type of hydrogenation catalyst known in the art is
It would be one of the group noble metals, such as platinum, deposited on a porous support such as alumina. This type of catalyst is often preferred due to its high hydrogenation activity, relatively low loss of feed to significantly lower boiling products, and relatively mild operating conditions. . However, this type of catalyst was easily deactivated by small amounts of sulfur contained in the feed. It would be desirable to have a hydrogenation process that is more economically attractive for a variety of purposes, such as the production of white oils and white oil bases, or the improvement of jet fuel properties. The principal objective of the present invention is therefore to develop a process for the hydrogenation of olefins and aromatics in jet fuels and white oils, which operates under relatively mild conditions and which It has a high level of hydrogenation activity, ie, a low ability to convert its feed to significantly lower boiling point products, and is not poisoned by sulfur-containing feeds. One aspect of the invention is a method of hydrogenating olefins and aromatics present in a hydrocarbon feedstock, which comprises hydrogenating the feedstock from about 204.4 to
Under hydrogenation conditions including temperatures between 382.2°C (approximately 400 and 720°C) (1) an amorphous base component, (2) a silica/alumina molar ratio comprising 5 to 70% by weight of the total catalyst and having a silica/alumina molar ratio of at least 2.5. and (3) contacting with hydrogen in the presence of a catalyst comprising a mixture of a crystalline aluminosilicate component having an alkali metal content of not more than about 2.0% by weight as alkali oxides per total aluminosilicate component, and (3) a hydrogenation component. the catalyst is heated for a period sufficient to suppress the cracking activity of the catalyst before it is used to hydrogenate the feedstock, i.e.
At least as a nitrogen-containing organic compound for 200 hours
Pretreated with a hydrocarbon stream containing 100 ppm nitrogen. The process of the present invention hydrogenates a hydrocarbon stream containing olefins and aromatics and having an initial boiling point (at atmospheric pressure) above about 93.3° C. (i.e. 20
weight% or less). It has been found to be particularly useful in the production of white oils and white oil bases and in improving the properties of jet fuels. In a preferred embodiment of the invention, the feed will be substantially nitrogen-free (ie, substantially 100 ppm or less). An important aspect of the present invention is to provide carbonization containing a relatively high concentration of a nitrogen-containing organic compound or an ammonia precursor for a sufficient period of time to suppress the cracking activity of the catalyst before using the catalyst to hydrogenate a feedstock. The catalyst is pretreated with a stream of hydrogen. This type of catalyst is basically a cracking catalyst, but treating the catalyst with relatively high amounts of nitrogen as a nitrogen-containing organic compound suppresses its hydrocracking activity and makes it resistant to sulfur and nitrogen. It has been found that a catalyst with relatively high hydrogenation activity can be obtained. Catalysts subjected to such treatment are therefore typically associated with the use of such zeolite-containing catalysts, resulting in unacceptably low yields of oil or jet fuel to lower boiling products (e.g. gasoline). It is a sulfur and nitrogen resistant hydrogenation catalyst useful in producing white oils and jet fuels without depletion. Any petroleum distillate hydrocarbon stream containing organic nitrogen compounds can be used in the treatment of this catalyst, but preferably the stream contains at least 100 ppm nitrogen and no more than 5 ppm metals. By organic nitrogen compounds or nitrogen-containing organic compounds is meant a group of nitrogen compounds that naturally occur in petroleum distillate streams, such as, but not limited to, pyridines, pyrroles and their associated compounds. The catalyst may be treated by contacting it with the organic nitrogen-containing hydrocarbon simultaneously with the feedstock or prior to catalyst-feedstock contact.
The catalyst is preferably treated prior to its contact with the feedstock, in which case the catalyst is said to be pretreated. There are three different ways to treat or pre-treat the catalyst. One method is by pretreating the catalyst with a high nitrogen-containing hydrocarbon stream, such as a petroleum distillate, other than the feedstock to be hydrogenated. Another method is to add an organic nitrogen-containing compound to the feed for a sufficient time to suppress the cracking activity of the catalyst if the feed typically contains less than 100 ppm nitrogen. Of course, after the cracking activity of the catalyst has been suppressed, the catalyst will perform its function of hydrogenating the feed and it will no longer be necessary to add nitrogen compounds to the feed. Yet another method is to reduce its cracking activity by contacting the catalyst in its neat form as a nitrogen-containing organic compound with a feed to be hydrogenated containing nitrogen at a relatively high concentration (i.e. >100 ppm). It is to suppress the In this case, the hydrocracking activity of the catalyst will be severely inhibited by the initial contact with the feedstock, but then the catalyst will act to hydrogenate the feed and subsequent During hydrogenation, hydrocracking conversion of the feed to low boiling products is kept to a minimum (ie, below 20% by weight). Another important aspect of the present invention is that the hydrogenation salinity of the feed is reduced to about 382.2°C (about 720°C) in order to limit hydrocracking to significantly lower boiling products to less than about 20% by weight. This is related to the finding that the limit should not be exceeded. The highest hydrogenation temperature meeting these requirements is a function of the crystalline aluminosilicate content of the catalyst, approximately 5% by weight in the catalyst.
The maximum temperature for crystalline aluminosilicate is 382.2℃
(720〓) was found to correspond. The term low boiling product means a product that boils below approximately the initial boiling point of its feed. if,
Corresponding to 5 and 30% by weight of the crystalline aluminosilicate content of the catalyst, respectively, the hydrogenation temperature is approximately
Above 382.2°C (approximately 720〓) and 371.1°C (700〓), substantial amounts of feed are hydrocracked to low-boiling products even in the presence of high nitrogen-containing feeds. I understood. This phenomenon is illustrated by the accompanying figure. The figure shows the conversion of high nitrogen content feed to products boiling below the initial boiling point of that feed, respectively.
Figure 2 is a plot of hydrogenation temperature as a function of hydrogenation temperature over two catalysts useful in this invention containing 30% by weight faujasite and detailed in Example 5. The catalyst can be treated or pretreated, fixed bed, fluidized bed,
Or it can be used as an ebulating bed. The following conditions have been found to be suitable for treating or pretreating the catalyst with an organic nitrogen compound-containing feed.

Concentrations of Table 1 The process of the invention can be applied to the hydrogenation of all hydrocarbon streams containing olefins and aromatics.
It is particularly useful in the production of industrial white oils and white oil bases and in improving the properties of jet fuels. The following are hydrogenation conditions operable and suitable for the process of the invention.

[Table] Catalyst activity may decrease after 60 days of continuous use or more. However, the catalyst can be regenerated by removing deactivation deposits from the catalyst surface by conventional methods including, for example, controlled combustion. Feed materials suitable for use in the process of the invention include hydrocarbons, mixtures of hydrocarbons, especially hydrocarbon fractions, the major part of which is at about 93.3°C.
The following initial boiling points are included: Unless otherwise specified, boiling points are at atmospheric pressure. Non-limiting examples of useful feedstocks for this process include crude oil distillates from paraffinic and naphthenic crude oils;
Included are deasphalted residual oils, fractions of catalytic cracking cycle oils, coker distillates, pyrolysis oils, hydrocracking oils, and/or solvent refinements. These fractions can be derived from petroleum crude oil, shale oil, tar sands oil, coal hydrogenation products, and the like.
Suitable feedstocks for jet fuel production range from 93.3 to
Initial boiling point within the range of 204.4℃ (200~400〓) and 260
Indicates a final boiling point in the range of ~315.6°C (500-600〓). Suitable feedstocks for technical white oils and white oil bases include crude and/or semi-refined distillates from naphthenic or paraffinic crude oils. For white oil production, the viscosity and specific gravity of the product are key specifications that determine the feedstock. The process of the invention may be carried out using conventional or other convenient methods under the reaction conditions described above and by contacting the catalysts described in more detail below. For example, the feed stock can be preheated and loaded into a high pressure vessel used as a hydroprocessor.
The feedstock can be mixed with hydrogen before being loaded into the hydroprocessor, or alternatively, the feedstock and hydrogen can be loaded as separate, separate streams into the hydroprocessor. Preferably,
The catalyst is arranged in one or more fixed beds within the reaction zone of the hydroprocessor and the feedstock and hydrogen are charged in contact therewith as an upper stream and/or a lower stream. The effluent from the hydroprocessor is cooled and separated into a cold liquid hydrogenation product and a cold gaseous stream. The stream, which is gaseous at ambient temperature, consists primarily of hydrogen and can optionally be recycled to the hydroprocessor as part of the hydrogen load. Alternatively, a portion of the gas stream may be vented to maintain hydrogen purity within the hydroprocessor. In some applications, it is necessary to remove low-boiling components from the hydrogenation product, which is liquid at room temperature, by atmospheric pressure or vacuum stripping in order to bring the product into compliance with flash point and/or viscosity specifications. . The catalyst to be treated according to the present invention consists of a mixture of (1) an amorphous component, (2) a crystalline aluminosilicate component ranging from 5 to 70% by weight (based on total catalyst), and (3) a hydrogenation component. This type of catalyst is disclosed in US Pat. No. 3,547,807 and US Pat.
No. 3,304,254, which is exemplified and more fully described. Preferably, the catalyst comprises (1) a primary component consisting of an amorphous support having deposited thereon in the form of oxides of nickel and/or molybdenum, (2) a silica/alumina molar ratio of about 2.5 or greater and a final an alkali metal content of not more than 2.0% by weight (as alkali metal oxide) per aluminosilicate composition, and one or more transition metal hydrogenation components deposited or exchanged thereon, i.e. It consists of a mixture of minor components consisting of crystalline aluminosilicate zeolites containing oxides of nickel and/or molybdenum. The amorphous component (support) of the catalyst can consist of one or more of a number of inorganic non-crystalline materials with high porosity. Typical porous materials that may be used include metals and metal alloys; sintered glasses; bricks; kea algae; inorganic refractory oxides; metal phosphates such as boron phosphate, calcium phosphate, and zirconium phosphate; metals Included are sulfides such as iron sulfide and nickel sulfide; inorganic oxide gels, etc. Suitable inorganic oxide support materials include -A of the periodic table;
-A and one or more metal oxides selected from the group. Non-limiting examples of such oxides include aluminum oxide, titania, zirconia, magnesium oxide, silicon oxide, titanium oxide, silica stabilized alumina, and the like. Suitable hydrogenation components that can be added to this porous support are oxides of transition metals, the metals being nickel and molybdenum. The metal oxides can be added to the carrier alone or in combination. The hydrogenation component is added to the support in a small proportion ranging from about 1 to 25 weight percent based on the total amorphous content of the catalyst. Preferably, the initial catalyst composition consists of a silica/alumina support containing molybdenum trioxide and nickel oxide hydrogenation components. Silica in an amorphous carrier/
The alumina weight ratio is 20:1 to 1:20, preferably 1:
It can range from 4 to 1:6. The weight ratio of molybdenum trioxide/nickel oxide in the amorphous carrier is 1:25.
-25:1, preferably 6:1 to 4:1. Finally, the weight ratio of support to hydrogenation component may be about 20:1 to 1:20, preferably 4:1 to 8:1. The amorphous component of the catalyst may be produced in any suitable manner. Thus, for example, when using silica/alumina, the silica and alumina may be mechanically mixed or chemically hybridized with the metal oxide, such as by co-gelation. The silica or alumina may have one or more metal oxides deposited thereon before being mixed with the others. Alternatively, the silica and alumina may be mixed first and then impregnated with the metal oxide. The crystalline aluminosilicate (fluid component) used to prepare the crystalline component of the catalyst consists of one or more natural or synthetic zeolites. Examples of particularly suitable zeolites are zeolite X, zeolite Y, zeolite L, phaujasite and mordenite. Synthetic zeolites are generally described in US Pat. Nos. 2,882,244, 3,130,007 and 3,216,789. The silica/alumina molar ratio of useful aluminosilicates is greater than or equal to 2.5, preferably in the range of about 2.5 to 10. Most preferably, this ratio will range between about 3 and 6. These materials are essentially dehydrated forms of crystalline hydrated silicic zeolites containing varying amounts of alkali metals and aluminum with or without other metals. The alkali metal atoms in the zeolite, silicon, aluminum and oxygen, are arranged in the form of an aluminosilicate with a consistent, conformable crystalline structure. This structure includes a large number of small cavities interconnected by a large number of smaller holes or passageways. These voids and passageways are uniform in size. The pore diameter of the crystalline aluminosilicate may range from 5 to 15 Å, preferably from 5 to 10 Å. The aluminosilicate component can include sieves of one particular pore diameter or a mixture of sieves of various pore diameters. Thus, for example, a mixture of 5 Å and 13 Å sieves can be used as the aluminosilicate component. Synthetic zeolites such as Y-type phaujasite are preferred and are made by well known methods such as those described in US Pat. No. 3,130,007. The aluminosilicate can be of the hydrogen type, polyvalent metal type, or mixed hydrogen-polyvalent metal type. The polyvalent metal or hydrogen forms of the aluminosilicate components can be prepared by all known methods described in the literature. Typical of such methods is ion exchange of the alkali metal cations contained in the aluminosilicate with aluminum ions or other easily decomposable cations, such as methyl-substituted quaternary ammonium ions. This exchanged aluminosilicate is then heated to an elevated temperature of approximately 300-600°C to drive out the ammonia, thereby producing hydrogen-type materials. The degree of polyvalent metal or hydrogen exchange should be at least about 20% of the highest theoretically possible value, preferably at least about 40%. In either case, the crystalline aluminosilicate composition comprises no more than about 6.0% by weight, preferably no more than 2.0% by weight of the final aluminosilicate composition;
That is, it must contain about 0.3-0.5% by weight or less of alkali metal oxide. The resulting hydrogen-aluminosilicate may be used as is, or it may be heated to an elevated temperature, e.g. 427-704°C.
They can also be subjected to steam treatment to stabilize them against hydrothermal deterioration. In many cases, steam treatment will achieve a favorable modification of the crystal structure, resulting in improved selectivity. Hydrogen-polyvalent metal mixed type aluminosilicates are also included in the present invention. In one embodiment, the metal type aluminosilicate is ion-exchanged with ammonium cations and then partially back-exchanged with a solution of the desired metal salt until the desired degree of exchange is achieved. The remaining ammonium ions are later decomposed into hydrogen ions during thermal activation. Again, it is preferred that at least 40% of the monovalent metal cations are replaced by hydrogen and polyvalent metal ions. Suitably the multivalent metal exchanged is a transition metal, preferably selected from groups -B and of the periodic table. Suitable metals include nickel, molybdenum, tungsten, and the like. The most preferred metal is nickel. The amount of nickel (or other metal) present in the aluminosilicate (as ion-exchanged metal) can range from 0.1 to 20% by weight based on the final aluminosilicate composition. In addition to the ion-exchanged polyvalent metals, the aluminosilicate may contain, as non-exchanged components, hydrogenated components which are oxides of nickel and/or molybdenum. Such hydrogenated components can be combined with the aluminosilicate by any method that gives a suitably intimate mixture, such as impregnation. A particularly preferred metal is nickel in its oxide form. The total amount of hydrogenated components present in the final aluminosilicate composition ranges from about 1 to 1 per final aluminosilicate composition.
It may range from 50% by weight, preferably from 10 to 25% by weight. The final weight percent composition of the crystalline component of the total catalyst is about 5-70% by weight, preferably about 5-30% by weight of the total catalyst.
for example 20% by weight. The amorphous and crystalline aluminosilicate components of the catalyst are combined in any suitable manner, such as mechanical mixing of the particles, thereby forming a particulate composite, which is then dried; = Can be burned. Catalysts may also be prepared by extruding a wet plastic mixture of powdered components, followed by drying and calcination. Preferably, the finished catalyst is prepared by mixing the metal exchanged zeolite component with alumina or silica stabilized alumina and extruding the mixture into catalyst pellets. The pellets are then impregnated with an aqueous solution of nickel and/or molybdenum material to form the final catalyst. A particularly preferred catalyst composition consists of the following composition: NiO 3% by weight MoO ₃ 16% by weight Ni-phaujasite 20% by weight A ₂ O ₃ balance The catalyst is preferably treated with hydrogen sulfide or nitrogen before use. Presulfurized by conventional methods such as carbon sulfide treatment. During the course of the hydrogenation operation, the exact chemical composition of the hydrogenation components present on the support is not known. However, the hydrogenation component will likely be present in a mixed elemental metal/metal oxide/metal sulfide type. After sulfidation, the catalyst is treated with a hydrocarbon stream containing at least 100 ppm nitrogen as nitrogen-containing organic compounds under the conditions described above. The mechanism by which nitrogen compounds suppress the cracking activity of the catalyst while leaving the hydrogenation activity essentially unchanged is unknown. However, it is believed that the nitrogen in the hydrocarbon stream is converted to ammonia and it is substantially the ammonia nitrogen that is responsible for inhibiting cracking activity. The following examples illustrate the effectiveness with which hydrogenation activity is primarily achieved by pretreating the catalyst of the present invention with a nitrogen-containing hydrocarbon stream. Example 1 Phenol refined oil (raffinate) from Coastal Crude (naphthenic crude oil)
was hydrotreated using a sulfided catalyst which had not been previously pretreated with an organic nitrogen-containing hydrocarbon stream according to the method of the invention. The same catalyst was then treated with an organic nitrogen-containing hydrocarbon stream as described above and again used to hydrotreat another sample of the same Coastal Crude phenolic refined oil. Used for catalyst pretreatment. The nitrogen-containing hydrocarbon stream used for pretreatment of the catalyst was a raw distillate of Tia Juana, a naphthenic crude oil whose Tia Juana crude distillate and Coastal Crude Phenol refined oil are shown in the table. The composition of the catalyst is also shown in the table, while the conditions used to treat the catalyst are shown in the table. The results of these tests are shown in the table. The data in the table clearly show that the hydrocracking activity of the catalyst was significantly inhibited by pre-treating the catalyst with organic nitrogen-containing crude distillate of Tiazhuana. Comparing the properties of the untreated refined oil feed shown in the table with the properties of the same feed (total liquid product) after passing over the treated and untreated catalyst in the table, a significant decrease in the refractive index and It can be seen that the viscosity of the feed passed over the untreated catalyst decreases by more than an order of magnitude with increasing AP1 weight. This indicates that the untreated catalyst has substantially hydrocracked the feed. On the other hand, a comparison of the same properties of a refined oil feed passed over the treated catalyst shows that little or no hydrocracking occurred. This is shown by the slight decrease in viscosity and refractive index along with no increase in PA1 weight. This Tiajiuana crude distillate is naphthene-based, and the name 58/60LCT in the table indicates that its viscosity range is between 58 and 60 SUS at 37.8℃ (100〓), and that it has been tested in the low cold test (low cold test).
test) or low pour point distillate
distillate). As shown in the table, its nitrogen content was about 500 ppm.

【table】

[Table] Huaujasite/Remainder alumina

[Table] The catalyst composition is 3%/NiO/16%MoO ₃ /20%
Ni-faujasite/remainder alumina,
Manufactured under the following operating method and conditions. A sample of commercially available sodium-fauziaside was
It was converted to ammonium form by catalysis with ammonium nitrate solution for 48 hours. After washing with water, the material was further catalyzed with nickel nitrate solution to exchange some of the ammonium ions with nickel ions. Approximately 537.8℃
After being calcined at (approx. (calculated as Na ₂ O). This replacement Huauja site base (20 parts by weight)
and amorphous alumina (80 parts by weight) were mixed with water to produce a mixture that could be extruded using a batch piston extruder. After extrusion, the material was stored overnight in a 148.9
Dry at 300 °C. Approximately 1/16 inch (0.159
The extrudate with a diameter of cm) is cut to an appropriate length,
Sieve to remove fine parts and heat at 537.8℃ (1000〓)
Time = baked. The catalyst was wetted with ammonium molybdate solution, dried overnight at about 148.9°C (about 300°C), and molybdenum was added. Similarly, nickel was added using a nickel nitrate solution. Finally, the catalyst was calcined at 537.8°C (1000°C) for 3 hours. EXAMPLE 2 This example demonstrates the relatively high conversion of feed to lube oil product using the pretreated catalyst of Example 1 without the useful benefits normally associated with the use of this type of catalyst. Illustratively compared to a relatively low (approximately 50% or less) conversion ratio to lube oil. As shown in the table, the feed in this example was a lubricating oil fraction (boiling point 376.7°C [710°C] or higher) of a 50/50 blend of hydrocracked high vacuum gas oil and deasphalted oil. . A portion of this feed was passed over the pretreated catalyst of Example 1 and another portion of the same feed was passed over a sample of the same catalyst that had not been pretreated with a high nitrogen containing hydrocarbon stream. The results obtained in the analysis of the products of each experiment are compared in a table. Catalysts that were not pretreated by the method of the invention were
It had a fairly high hydrogenation activity at 287.8°C (550〓), giving a product that met or approximated technical white oil specifications. However, due to high hydrocracking activity, a total of 376.7℃ (710℃)
〓)＋waxy lube yield is small
32.9% by weight corresponded to a conversion of 67.1% by weight to low-boiling products. However, pretreated catalysts have much lower conversion rates to low-boiling products,
1.8% by weight at 287.8℃ (550〓), 315.6℃ (600〓)
gave 6.3% by weight. These operations give a very broad saturation of aromatics and the hydrogenated lube fraction is considered suitable for use as an industrial white oil. The following examples illustrate the advantages of the process of the invention in the production of industrial white oils.

【table】

【table】

[Table] Amount % ⁽²⁾

[Table] (3) By silica gel chromatography.
Example 3 A dewaxed phenol refined oil from Tiajyuana 102 crude oil (naphthenic crude oil) was treated with two catalysts: catalyst A having the composition and pretreatment according to Example 1;
Hydroprocessing was performed using Catalyst B, which is conventional cobalt molybdate on alumina. The same pressure, gas velocity and feed rate conditions were used for both catalysts. The severity of the hydrotreatment in each case was temperature controlled and adjusted to the highest possible level consistent with the minimum permissible specific gravity of the hydrotreated product after topping (0.868). Using catalyst A (of the present invention), 315.6°C
(600〓) gave a product with a specific gravity of 0.868.
354.4℃ (670〓) using catalyst B (prior art)
temperature was required for almost the same specific gravity value of 0.868. The above catalyst B has a commercial name: Spence 5/
25 Comox catalyst with the following nominal composition: 5.2% cobalt oxide/
25.3% molybdenum oxide/balance alumina. Both catalysts A
and B were previously sulfided in conventional manner, for example by treatment with H ₂ S diluted with hydrogen, before use. In addition to being presulfided, catalyst A was also pretreated with an organic nitrogen-containing feed as described in Example 1. The hydrogenation products obtained as a result of using the two catalysts have similar viscosities, and by adjusting the topping temperature, other properties such as specific gravity, sulfur content and aromatics content can be significantly influenced. It was possible to achieve exactly the same viscosity level without giving rise to The ion content of both was less than 10 ppm. Comparative data is shown in the table below.

[Table] The difference between the products obtained using these two catalysts lies mainly in their aromatic compound content. Catalyst A
contains significantly less aromatic compounds than catalyst B, i.e.
It gave a product with 1.6% by weight of aromatic carbon atoms as determined by infrared spectroscopy and 2.0% by weight of aromatic carbon atoms of 6.3% as determined by silica gel chromatography. The product obtained by using Catalyst A meets the specifications for industrial white oil. In contrast, the higher aromatic content products obtained by using catalyst B would not be acceptable as industrial white oils. Moreover, the product obtained by using catalyst A will be more easily converted into a medicinal white oil by hydrogenation or acid treatment over a metal catalyst than the product obtained by using catalyst B. To produce a product with the same low aromatic content as with catalyst A using catalyst B, it would be necessary to increase the hydroprocessing pressure and/or decrease the feed rate. It is therefore clear that the use of catalyst A allows the use of less severe and therefore less expensive hydroprocessing operations. The method of the present invention improves smoke point, luminometer numbers by aromatic compound separation.
It is also useful for hydrogenating jet fuel to reduce Additionally, jet fuels obtained from thermal conversion processes such as coking contain undesirable olefinic compounds which can also be reduced by hydrogenation. The catalysts used herein have higher hydrogenation activity than conventional amorphous refractory metal oxide supported metals of the -B and/or group such as nickel, platinum or palladium. That is, jet fuel can be hydrogenated using lower pressures and/or higher space velocities. Furthermore, since the catalysts used in the process of the invention have metals in the form of sulfides, they are not easily deactivated by trace amounts of sulfur and nitrogen compounds present in the jet fuel stream. . The use of the method of the present invention in improving the properties of jet fuel is illustrated by the following example. Example 4 Distillate from Coastal Crude with boiling point range 205.6-298.9°C (402-570〓) (5 and 95 by GC distillation according to ASTM D2887-70T)
% removed) was hydrotreated by the use of two catalysts, Catalyst A according to the process of the invention and Catalyst B of conventional cobalt molybdate on alumina. The compositions of these catalysts have already been described in Examples 1 and 3. The severity of the hydrotreatment in each case was controlled by reaction temperature and pressure, and liquid inflow rate. As can be seen from the table below, Catalyst A of the present invention performs better by FIA analysis at lower temperatures and pressures and at twice the inflow rate compared to Catalyst B.
The aromatics content of the feed stock was reduced to levels well below the maximum jet fuel specification of 20% by volume.

Table: The hydroprocessed products from both Catalysts A and B exhibit substantially equal smoke points, luminometer numbers, freezing points, pour points, colors, and flash points, each within jet fuel specifications. For some jet fuel specifications, the final boiling point of the feedstock may have to be reduced slightly (e.g.
up to 287.8℃ (approximately 550℃). The above data indicate that significant savings in catalyst supplies and equipment requirements can be obtained by using Catalyst A over Catalyst B in upgrading off-spec (e.g. high aromatics content) jet fuels. easily understood. EXAMPLE 5 This example uses a 5 wt. The aluminosilicate content illustrates that the hydrogenation temperature should not exceed about 720°C. The feed in this example is approximately 352.8-595°C (approximately 667-1103°C
A high vacuum gas oil derived from West Texas, Sour Crude oil with a boiling point range of Ta. This feed was passed over two different catalysts A and B (consisting of nickel tungstate on a mixture of Ni-phaujasite and alumina) in the presence of hydrogen. A contained 5% by weight of faugiasite, and B contained 30% by weight. Both catalysts were virtually identical except for the faugiasite content. This reaction condition requires 175Kg/cm ²
(2500 pgig) and a space velocity of 0.5 V/V/hr. Approximately 371.1℃ [approx. 700〓] in the supply section
The degree of conversion to the following boiling point products is plotted in a diagram as a function of hydrogenation temperature. That is, this figure is 30%
Approximately 371.1℃ [approx. 700
At temperatures above 〓〕, a significant amount (greater than 20%) of the feed is converted to lower boiling point products, and the conversion is exponentially greater than 100% conversion at a temperature of about 398.9°C [about 750〓]. It is shown that it increases to . The maximum temperature for 5% faugiasite is approximately 382.2℃ [approximately 720〓]
It was hot.

[Brief explanation of drawings]

The accompanying diagram shows the conversion of a relatively high nitrogen content feed to low boiling products as a function of hydrogenation temperature over two catalysts useful in the present invention with different faugiasite contents. This is an example.

Claims (1)

[Claims] 1. Olefins and aromatic compounds present in a hydrocarbon feedstock containing 100 ppm or less of nitrogen as nitrogen-containing organic compounds in the presence of a catalyst.
In a hydrogenation process comprising contacting with hydrogen under hydrogenation conditions including a temperature not exceeding 382.2°C (720°C), the catalyst is (1) from the group consisting of -A, -A and groups of the periodic table; Highly porous inorganic amorphous material consisting of one or more selected oxides
an amorphous base component consisting of (2) 5 to 70% by weight of the total catalyst, with a silica/alumina molar ratio of at least 2.5 and 2.0% by weight (as alkali oxide) per total aluminosilicate component; (3) a hydrogenation component consisting of oxides of nickel and/or molybdenum, wherein the catalyst is a feedstock with a low nitrogen compound content; 5 to 200 hours to suppress the cracking activity of the catalyst before being used to hydrogenate the catalyst.
A method as above consisting of pretreatment with a hydrocarbon stream containing at least 100 ppm nitrogen as nitrogen-containing organic compounds. 2 Catalyst treatment conditions are 204.4-398.9℃ (400-750℃)
Temperature within the range of 〓), 35~700Kg/ ^cm2 (500~
10,000 psig) and a liquid hourly space velocity of 0.1 to 10.0 V/V/hr. 3. The method of claim 2, wherein the crystalline aluminosilicate component of the catalyst is 5 to 30% by weight of the total catalyst. 4. The amorphous basic component of the catalyst consists of alumina.
A method according to claim 3. 5. The method of claim 4, wherein the amorphous base component is silica-stabilized alumina, the molar ratio of silica to alumina being from 1:4 to 1:6. 6. The method of claim 2, wherein the treatment hydrocarbon stream does not contain more than 5 ppm of metals. 7. The method of claim 1, wherein the hydrocarbon feedstock is a crude or semi-refined petroleum distillate. 8. The method of claim 1, wherein the hydrocarbon feedstock is a petroleum distillate jet fuel feedstock.