JPH03504866A - Manufacture of high octane gasoline - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Manufacture of high octane gasoline The present invention relates to the production of high octane gasoline, and more particularly to catalytic cracking and by hydrocracking of highly aromatic fractions obtained from petroleum refining operations and other petroleum refining operations. Concerning the production of 1-ioctane gasoline.

Under current conditions, refineries are converting an ever-increasing proportion of raw materials into petroleum and other petroleum products. Converted to premium fuels and middle distillates such as diesel and diesel fuels It is necessary. Transfer of a substantial fraction of heavy liquids in current refineries The process is carried out using the fluid catalytic cracking (FCC) method and the thermofor By catalytic cracking method represented by catalytic cracking (TCC) method. Both methods are thermally severe In the process, the carbon becomes coke and residual fractions that become defective. i.e. contact During decomposition, high molecular weight liquids undergo disproportionation reactions to form lighter liquids and relatively hydrogen-rich liquids. This results in heavier fractions and residues deficient in hydrogen and aromatic hydrogen.

Catalytic cracking in the absence of hydrogen does not result in significant desulfurization and reduces the nitrogen content of the feedstock. is also not selectively reduced by coke. Therefore, sulfur and nitrogen are heavier becomes noticeably thicker in the cracking products. Therefore, by cracking , high sulfur and nitrogen levels, substantial, highly aromatic, hydrogen deficient, medium and a heavy fraction are obtained. These liquids are refractory, difficult to convert, and Adding non-refractory feedstocks to the catalytic cracker, as this often inhibits their conversion. Recycling is often undesirable. In general, the level of contaminants in petro atoms is , two typical FCC product fractions: light cycle oil and FC Sulfur and nitrogen content of C main column residual oil (ratios and ), cents are by weight), the boiling points of the fractions are as shown in Table 1. increases with

Table 1 FCC product fraction Due to current market demands, refractory product streams, even if commercially important Especially as a product with <0 force (produced).

Previously, light and heavy cycle oils and FCC main column resid 6 were reformed to No. , 2 fuel oil and light fuel oil such as N016 fuel oil (1 could be sold as heavy fuel oil).

The reformation of light cycle oils is usually carried out by relatively low-severity low-pressure hydrodesulphurization (CHD). The cycle stock (cycle 5to ck) in a straight run obtained from the same crude blend fed to the catalytic cracker. Mix with quality fraction. A more detailed explanation of this technology can be found at Naru (O1land Gas Journal), p87-p94 (198 Published on May 31, 2015).

However, now the demand for fuel oil is decreasing. At the same time, oil demand and supply Changes will reduce the quality of crude feedstock available to refiners, which will lead to even larger quantities of of refractory cycle stock (feedstock oil) is formed. As a result, refiners while producing larger quantities of poor quality cycle streams from the catalytic cracker. The current situation is that the market for disposing of them is decreasing.

Many oil refineries use light cycle oil obtained from FCC units. t cycle oil, LCO) is N002 fuel oil or diesel fuel oil. Catalytic hydrodesulfurization (CHD) to produce diesel fuel is an important component of the feedstock to the esulfurization unit.

The remaining components are usually virgin, obtained directly from the crude distillation unit. in) Kerosene. The high aromatic nature of LCO makes it especially suitable for FCC units at the highest gas levels. CHD becomes more difficult to operate when operating in Solin mode and the cetane number and its properties as a No. 2 fuel or diesel oil measured by sulfur content. There is a possibility of obtaining a product that is at the limit.

Another market for middle distillate streams is automotive diesel fuel. However, the norm For proper operation of a typical automobile diesel engine, diesel fuel is required. must satisfy a minimum cetane number specification of 45. Cetane number is the aromatic content Typically aromatics content is 80% or higher, as The cetane number of the highly aromatic cycle oil obtained from the above cracker is low, 4 or It is 5. The cetane numbers of these cycle stocks are applied to the conventional CHD technology described above. In order to raise the temperature to a more satisfactory level, a substantial and uneconomical amount of hydrogen or and high pressure treatment is required.

Due to these problems associated with its use as a fuel, the FC of untreated light cycle oil Recycling to CU has been proposed as a method to reduce the amount of LCO. L The benefits expected from CO recycling include conversion of LCO to gasoline, N Withdrawal of kerosene from 082 fuel oil and improvement of cetane in diesel fuel oil These include a reduction in the use of drugs. However, these benefits are often outweighed by the FCC Increased coke production in the unit, reduced quality of LCO obtained and heavy The disadvantages such as increased oil and gas consumption are greater.

Typical LCO is a refractory stock and has lower quality compared to freshly supplied FCC feed. Most refineries do not recycle untreated LCO due to stomach. One of the other methods for reforming LCO that is commonly practiced is to Strictly hydrotreated before recycling or severely hydrotreated and high pressure This is to supply the fuel to the hydrocracker. In either case, the purpose of hydrotreating reduces the peteroatom content to low levels while saturating the polyaromatics. The aim is to improve degradability. This increases the convertibility of these aromatic streams. However, the economic disadvantages due to high hydrogen consumption and high pressure processing are significant. Hey. Furthermore, when gasoline production is required, it is possible to restore its aromatic character and The naphtha may need to be reformed to meet tanning specifications.

Hydrocracking is a product used to reform high-boiling refractory products obtained from catalytic cracking. Ru. Catalytic cracking equipment uses paraffinic gas oil, which is easier to crack, from the distillation unit. On the other hand, in a hydrocracker, the catalytic cracker is used to convert Accepts alkylated aromatic cycle oil, which is hydrogenated to create a lighter converted to oil. Petroleum Refining (Petroleum R) efining), 2nd edition, Gary J.H. and Handwork Sci. IE; Marcel Detzker, Ninny York (Gary, J, H, an dHandwerk, G, E; Marcel Dekker, N, Y,) pl　38-151　(1984); Setan Petroleum Chiku Noroshii (Modern P etroleum T technology), 4th edition, Hobson, C.D., Applied, Science Publishing (Hobson ,c,I),,Applied SsciencePubl,),p See 309-327 (1973). However, the catalytically cracked feed itself Hydrocracking processes using a mixture of biomass or virgin feed generally involve It is not possible to directly produce gasoline. The reason for this is that the method is Usually saturation of aromatics (especially refractory polynuclear aromatics), removal of heteroatoms in the form of inorganic substances. high hydrogen pressure to maximize removal and conversion of hydrogenated aromatics to paraffins. and at relatively high conversion levels. This makes it possible to Although diesel fuel is produced (due to the presence of n-paraffins), large amounts of low-octane The octane quality of gasoline is generally low due to its paraffin content. current usage In order to meet the product standards of the market, these gasolines must be Reforming is required with eventual yield loss. For example, U.S. Patent No. 3.13 No. 2.090 discloses a two-stage hydrocracking system for the production of gasoline. There is. However, the octane number of gasoline using straight distillate as raw material is 6B (R It is reported that OM+O). 80 (ROM+3) octane is coker distillate or and pyrolyzed gas oil feedstocks. Described herein High octane gasoline J gasoline contains 3xQ/gal of tetraethyl lead ) and ranges from 70 to 88 (RON 10). The octane number changes depending on the The octane number of these gasolines increases by about 4 to 6, so the octane number of these gasolines is according to the correct standard (ROM +O)+: Original, range from 65 to 83 (ROM+0).

Various low pressure hydrocracking processes have also been described. For example, U.S. Patent No. 3.867.2 No. 77 and No. 3.923.640 typically contain high (20-41) API gravity. A low-pressure hydrocracking process using various high-boiling point feedstocks has been described. The fee The use of a The alkyl groups present are relatively linear, formed by ring opening and decomposition of aromatics. Mixed with paraffin in naphtha, resulting in naphtha with low octane number . These methods are therefore not practical for directly producing high-octane gasoline. It's not something I'm satisfied with.

Other low-pressure hydrocracking methods for producing aromatic products have been described; The ability to produce high-octane gasoline from low-value refractory cracked oil is being evaluated. do not have. For example, U.S. Patent No. 4,435°275 provides a A method is described for producing aromatic middle distillates such as household heating oils under conditions of low conversion. However, for the production of the desired low-sulfur middle distillate, an octane number of 78 (R+O ) have only been reported.

A notable development is detailed in US Pat. No. 4,676,877. Contact Highly aromatic refractory feeds obtained from catalytic cracking and other oil refining processes can be produced at relatively low pressures. , typically 600 to 1000 psig (4250 to 7000 kPa absolute pressure). It is directly converted into high octane gasoline by hydrocracking, and the conversion rate is low. Typically, conversion to products below 385°F (195°C) is less than 50% by weight. (All SI equivalents herein are conveniently rounded for comparative convenience. This is a good value. All pressures shown in SI year units are absolute pressures). example For example, in a catalytic cracking operation, substantially dealkylation is typically performed at an API gravity of 5 to 25. By using a highly aromatic feed that is The ring opening of the partially hydrogenated bicyclic aromatic product produces a large amount of Monocyclic alkylaromatics (mainly benzene, toluene, xylene and trimethylbenzene) ) is obtained. Monocyclic aromatics are not only in the boiling point range of gasoline, but also in high Because it has a high cotane number, it is blended into gasoline boule at refineries without being reformed in advance. high-octane gasoline suitable for

A more advanced version of this technology is described in U.S. Patent No. 4.738.766. In this case, high octane gasoline has aromatic feed from catalytic cracking. It is produced from a relatively low-boiling fraction of These light cuts (li ght cut, light distillate) feed, Ganlin's octane or increase conversion to higher levels without negatively impacting catalyst aging rates. can be given.

In this method, the dealkylation feed is mixed with inorganic nitrogen and nitrogen in two reactors. Processed with or without interprocess separation of sulfur, sulfur, and light components. Ru. The first reactor in the sequence is a hydroprocessing reactor and is a nickel on alumina reactor. Comprising a metal with hydrogenation function on a non-acidic porous support such as molybdenum. Contains a conventional hydroprocessing catalyst. The second reactor contains an acidic decomposition function and It contains a hydrogenolysis catalyst that has both hydrogenation and hydrogenation functions. The hydrogenation function is It is usually endowed by metals from group VIA or A of the periodic table (IUPAC table) and is acidic. The function is to combine with porous binders, e.g. alumina, silica, silica-alumina. Combined porous, inorganic acidic solids, preferably large pore zeolites, e.g. It is endowed by zeolite X or zeolite Y.

The present inventors conducted hydrogenolysis using a catalyst that basically does not contain metal hydrogenation components. I discovered that it can wail. Hydrocracking is usually carried out using a trifunctional catalyst (i.e. hydrogenation (gold) genus) functions promote hydrogenation reactions, acidic functions promote decomposition and ring-opening reactions) This is unexpected since it is generally considered to be a method that requires there were.

The hydrocracking process is substantially similar to that described in U.S. Pat. using a dealkylated feed, with relatively low hydrogen pressure and hydrogen consumption. Produce high-octane gasoline at a cost.

The process is carried out with an acceptable cycle period and involves continuous regeneration of the catalyst. This is done under the distribution law.

According to the present invention, high octane from substantially dealkylated hydrocarbon feedstocks The method for producing products in the gasoline boiling range is based on the added metal component. A hydrocracking catalyst having substantially no hydrogenation function is used. Therefore, the hydrogenated content The decatalyst is essentially a porous inorganic solid with acidic functionality, preferably a porous inorganic solid. Oxide matrix, e.g. alumina, silica or silica-alumina Composed of pore size zeolite. The hydrocracking step is carried out after the hydrotreatment and is optional. In addition, the processing of light components and inorganic nitrogen and sulfur (ammonia and hydrogen sulfide) Interval separation may also be performed in between.

In the attached drawings, FIG. 1 is a schematic diagram of an apparatus for carrying out the method of the invention.

Figure 2 shows the aging of a monofunctional hydrocracking catalyst used with a light cycle oil feed. This is a graph showing.

Figure 3 shows gasoline product octane at various conversion levels for a monofunctional catalyst. It is a graph showing (R+O).

FIG. 4 is a graph showing hydrogen consumption at various conversion rates for a monofunctional catalyst. .

The feed used in the process of the invention is a highly aromatic, hydrogen deficient hydrocarbon flux. It is a version. These can be produced, for example, by FCC or by catalytic cracking operations. This is the substantially dealkylated fraction in the TCC unit. dealkylation The integrated feed can be fed to other refining units, e.g. delayed, contact or flow It can also be obtained from the moving bed hooking unisoto. However, in catalytic cracking units, In this case, most of the feeds are obtained and the present invention is described below. Explain with reference to. Alkyl groups, generally bulky, relatively large alkyl groups (Typically, but not limited to, alkyl having 5 to 9 carbon atoms) As a result, those that bind to aromatic moieties in the feed are removed during the decomposition process. These are the characteristics of catalytic cracking. Most of the gasoline products obtained from crackers are It is these separated alkyl groups that are present. Benzene, naphthalene, benzothi Aromatic moieties such as ophene, dibenzothiophene, and anthracene and phenyl Polynuclear aromatics (PNAs), such as threne, form high-boiling products from crackers. Ru. The mechanism for acid-catalyzed decomposition and similar reactions is that short-chain alkyl groups, Side chains with carbon numbers larger than 5 are removed, leaving mainly methyl and ethyl groups. follow ``substantially dealkylated'' decomposition products include small molecules such as methyl and ethyl. A small alkyl group remains as a side chain, but a large alkyl group, i.e. 5 carbon atoms, There are almost no remaining aromatic groups in ~9. one or more of these short chain alkyl groups, For example, 1.2 or more methyl groups may be present.

The aromatic content of this type of feed oil is greater than 50% by weight. So, for example, 70 % by weight or 80% by weight or more.

The hydrogen content of this type of highly aromatic feed is typically less than 14% by weight, usually 1 2.5% by weight or less, for example less than 10% or 9% by weight. API specific gravity , a measure of the aromaticity of a feed, is usually less than 30, and most often less than 25. or even less, for example less than 20. In most cases, the API ratio The weight ranges from 5 to 25 and the corresponding hydrogen content is from 8.5 to 12.5% by weight. . The sulfur content is typically 0.5-5% by weight and the nitrogen content is 50-100%. 0 ppm by weight.

The feed of the method of the present invention therefore has a full Microwave cycle oil or light cut with end point up to 345°C (6500F) It may be cycle oil. end point below 345°C (650°F), preferably 3 Use of light cut cycle oils below 15°C (600°F) may result in excessive catalyst aging. is desirable because it allows higher conversion levels during hydrocracking. the last stop When using a full range cycle oil with a temperature higher than 345°C (650°F), the conversion rate to the level specified in U.S. Pat. No. 4,676,887, i.e. per pass. less than 50% for gasoline boiling range products (below 385°F, below 196°C) preferably at a value proportional to the hydrogen pressure used (0.000% of the hydrogen pressure in psig). 05 times or less). Applicable process conditions are based on U.S. patents. See No. 4,676.887.

Accordingly, feeds suitable for the process of the present invention have an end point of 345°C (650'F). ), preferably less than 315°C (600'F). and decomposition product fractions. The initial boiling point is usually 150°C (300°F) ) or higher, such as 165°C (330°F) or 195°C (385° F). Light cut light cycle oil within this boiling point range (light c ut light cycle oil.

LCOs) are highly preferred.

Full range light cycle oil oil, F RLC○) usually has a boiling point of 195-400°C (385-7 50°F), which can also be used. Light cycle oil is usually 60-80 % aromatics and is substantially dealkylated as a result of the catalytic cracking process. good Other examples of suitable feedstocks include those obtained from delayed or fluidized bed coking processes. dealkylated liquid products.

The use of a dealkylation feed is an important feature of this process.

Mainly virgin oil or straight-run oil, such as catalytic cracking or coking High octane gasoline is not previously dealkylated by the method of Not manufactured. If the feed of the method of the invention is not previously dealkylated, Large alkyl groups in the feed are cracked during hydrogenolysis, resulting in naphtha Also found in fractions. These groups are relatively linear, so they are low octane. You can get gasoline. For example, a smaller alkyl side chain with 1 to 3 carbon atoms Even if present, it is not found in naphtha boiling range products from hydrocrackers (because affect the product octane (even if the conditions are severe enough to remove them). I won't give it. Dealkylated and non-dealkylated feedstocks When using a mixture, the octane number is the same as the octane number when using the feeds separately. The value is between . Dealkylated and non-dealkylated feedstocks Mixtures of feedstocks can be used in commercial operations, depending on the desired Gasoline must be subjected to a reforming process to obtain the carbon number There are many cases.

The catalysts used in the hydrocracking process are monofunctional, heterogeneous porous solid catalysts that (degradability) function, but at least in the initial stage before use, it is basically a hydrogenator. have no ability. Highly aromatic feeds contain relatively bulky bicyclic and polycyclic components. The pore size of the catalyst is such that these substances are present in the internal structure of the catalyst where decomposition occurs. It must be thick enough to fit. The pore size is at least 7.4 (zeolite and corresponding to the large hole dimensions of Y) would serve this purpose; is limited, the proportion of bulky polynuclear aromatics is very low, and for this reason For this reason, the hole dimensions must be much larger than those mentioned above. crystalline zeolite catalyst The pore size range is suitable for so-called amorphous materials such as alumina or silica-alumina. It is used advantageously from the viewpoint of its activity and toxicity resistance because it is limited in comparison. Ru.

Catalysts with aromatic selectivity, i.e., which crack aromatics over paraffins, are This is preferred because the feed is highly aromatic.

Preferred hydrocracking catalysts are crystalline catalysts, generally zeolites, especially zeolites. , Constraint Index It is a large pore zeolite (large pore size) with an index) of less than 2. For the purposes of the present invention , the term "zeolite" refers to porotectsilicate cate), i.e., porous crystalline material containing silicon and oxygen atoms as main components means silicate. Others including aluminum, gallium, boron, etc. Although other components are present, aluminum is preferred to obtain the necessary acidity. small amount The components of the catalyst may be present separately or as a mixture, or may be incorporated into the structure of the catalyst. may exist.

Zeolites with a silica to alumina molar ratio of at least 10:1 are useful. and the silica/alumina (molar ratio) is high (i.e. at least 50:1). Preferably, olites are used. This silica/alumina (molar ratio) is determined by normal analysis. It can be measured by this method. This ratio is due to the strong anionic framework structure of zeolite crystals. As closely as possible, represent the proportions in the binder or channel. Excludes thione or other forms of aluminum.

The extent to which zeolites control molecules of various sizes over their internal structure. A convenient measure of is the zeolite constraint index. Among them A zeolite strained index with highly restricted entrances and exits in the structural structure. The pores of this type of zeolite are usually small, e.g. less than 1 m. On the other hand, zeolites with relatively free entry into the internal zeolite structure have a low Hun Strain Index and typically have large pore sizes, e.g. Bigger than Gustrom. The method of measuring the constraint index is All described in Patent No. 4,016,218. Constraint index used in the method of the invention, the x is less than 2, preferably less than 1. This is a characteristic of the hydrocracking catalyst.

The constraint index (CI) of typical large pore materials is shown in Table 2 below. show.

Table 2 Due to the nature of the CI parameter and the technique for measuring it, the same zeolite may be tested under somewhat different conditions and therefore have different May indicate an int index. The constraint index is Varies depending on the severity of the operation (conversion) and the presence or absence of a binder. other Variables such as zeolite crystal size, occluded foreign matter, etc. affect the index. Select test conditions, e.g. temperature, and test the zeolite. For certain zeolites, one or more strain index can be set.

Zeolite can be used to maintain the Hung Strain Index within a certain range by changing conditions. If it is set as follows, it is considered to have such an index.

Large pore zeolites, i.e. zeolites with a constraint index of less than 2 The pore size is large enough to pass most of the components normally present in the feed. It is. These zeolites generally have pore sizes greater than 7 angstroms. For example, Zeolite Beta, Zeolite X1 Zeolite Y1 Hojia Site, ultra stable y (usy), dealumination Y (Deal Y), mordenite, Zeo with the structure of ZSM-3, ZSM-4, ZSM-18 and ZSM-20 Represented by light. Zeolite ZSM-20 is unique in its structure. It is similar to faujasite, but the silica/alumina ratio is much higher than that of faujasite, and various The same applies to zeolites Y1 in the form of , especially USY and De-AIY. Zeolai De-Y is the preferred catalyst, with more stable forms, especially USY or De-A Preferably used in IY.

Zeolite Beta has a Hunstraint Index of less than 2, but typically It does not behave exactly the same as a large-pore zeolite. Zeolite Beta is the inventive Although the pore size requirements for the hydrocracking catalyst used in the process are met, the performance Unfavorable due to ruffin selectivity behavior.

Due to its aromatic selectivity and large pore size, it is suitable for alumina and silica-alumina, etc. type hydrocracking catalysts may be used, but are not preferred.

Zeolite ZSM-4 is described in U.S. Patent No. 3.923.639 as Zeolite ZS M-20 is U.S. Patent No. 3.972.983, and Zeolite Beta is U.S. Patent No. 3.308.069 and Reissue Patent No. 28.341, Low Sodium Ultra Stable Y Molecular Sieve (USY) is disclosed in U.S. Patent Nos. 3,293.192 and 3. No. 449,070, dealuminated Y zeolite (Deal Y) is Zeolite UHP-Y manufactured by the method described in National Patent No. 3.442゜795 is described in US Pat. No. 4,401.556. These zeolite catalysts Please refer to these patents for details.

The catalyst must have an acidity, ie an alpha value greater than 1, for decomposition function.

The alpha value is a measure of the acidic function of zeolites and is described in a US patent, along with a detailed method for its measurement. No. 4,016,218 and Journal of Catalysis (J, Cat lysis), Vol. 2, pp. 278-287 (1966). death However, the catalyst was tested in a fixed bed operation using a highly aromatic feed at low hydrogen pressure. used, so to reduce aging the tooling tendency must be low. , for this reason low α values are preferred. α value between 1 and 200, preferably 10 0 or less (75 or less, for example 50, is useful).

Catalyst stability during extended cycle life is important and this depends on the catalyst structure and and by appropriately selecting the silica/alumina ratio. this The ratio depends on the initial zeolite synthesis conditions, or the steaming or framework structure aluminum by replacing the aluminum with other trivalents, such as boron, iron or gallium. This can be changed by subsequent dealumination. Steaming is preferred because of its simplicity. This is a good process. To ensure satisfactory catalyst stability, high silica/alcohol A lumina ratio of, for example, 50:1 or greater, such as 200:1, is preferred; This is achieved by Alkali metal content to a low value, e.g. less than 1%, e.g. It must be kept to 0.15% Na. This is a continuous sequential ammonium conversion and subsequent firing (calcination).

Identical to selectivity and other beneficial properties, zeolites can be heated between 399° and 538°C (5 00° to 1200°F), better than 260' to 694"C (7500 to 1 000'F) by treatment with steam at high temperatures. This process requires 10 Inert in an atmosphere of 0% water vapor or towards water vapor or substantially zeolite It may be carried out in an atmosphere consisting of a gas. Similar process at lower temperature and elevated pressure , e.g. 177° to 371°C (350' to 700°F), 1013 to 20260 It can be carried out at kPa (10 to 200 atmospheres).

The zeolite is preferably resistant to temperature and other conditions used in the process. Preferably, it is composited with a matrix comprising another substance. Mato The lix material is useful as a binder and is subject to the severe temperatures, pressures and and reactant feed rate conditions. useful matrix material Materials include synthetic and natural materials such as clay, silica and/or metals. Examples include oxides. The latter is a natural or synthetic gelatinous precipitate or aluminum Forms of gel containing mixtures of silica and metal oxides such as alumina and silica-alumina Either state is acceptable. The matrix may be in the form of a co-gel. natural Clays may be composited with zeolites, such as montmorillonite and kaolin. Examples include: Such clay may be in its originally mined, unprocessed state, or can be used after first being calcined and then subjected to acid treatment or chemical modification. Nothing The proportion of zeolite components and matrix on a water basis is 1 to 99% by weight of zeolite. zeolite content, more typically 5 to 80% by weight of the dry composite. content range. If the feed contains more than 20% of the material at 343°C (650°F) If the bonding matrix itself has a substantial volume of large pore size (0,0 It is an acidic substance with a substance of 1 μm (100 people) or more. Binder is preferred or to maintain mechanical integrity and aid impregnation with non-exchangeable metal cations. , complexed with zeolite before processing such as steaming, impregnation, exchange, etc.

The raw cations that bind to each of the crystalline silicate zeolites used herein are typically Various other cations may be substituted according to the techniques of . Typical substituted cations includes hydrogen, ammonium and metal cations, and mixtures of these cations It also includes things. Increased stability (in the case of rare earth cations) or desired functionality (for metals of group ■ or ■), useful cations include, for example Rare earth metals such as cancer, metals of groups I [A and B of the periodic table such as zinc and Mention may be made of metals from group 1 of the periodic table, such as latina and palladium. representative io The ion exchange technique involves contacting a specific zeolite with a salt of the desired substituted cation. be. A variety of salts can be used, but chlorides, nitrates and sulfates are particularly preferred. Delicious. Representative ion exchange technology is disclosed in U.S. Patent No. 3,140.249, No. No. 140.251 and No. 3,140,253, among others. It is shown.

After contacting with a solution of the desired substituted cation, the zeolite is preferably washed with water. dried at temperatures ranging from 65 to 315 °C (150 to 600 °F), then air-dried. in the range of 260-815°C (500-1500°F) in air or other inert gas Bake at a temperature of 1 to 48 hours or more.

Hydrocracking catalysts basically use metal components that provide hydrogenation-dehydrogenation functions. Does not include the front. Therefore, metals from groups VIA and A of the periodic table (IUPAC table) , e.g. tungsten, vanadium, zinc, molybdenum, rhenium, nickel , cobalt, chromium, manganese, or precious metals such as platinum, palladium etc., but these metals should at least be subjected to a comparable hydrogenation machine as a catalyst before use. There may be an amount present that does not provide any performance. During operation, especially nickel and vanadium Metals such as aluminum are removed from the feed, which may provide hydrogenation activity. However, this is not essential to the operation of the method.

A method using a full range LCO feed is schematically illustrated in FIG.

The residual oil or gas oil feed to the FCC unit 10 is in the FCC unit. The decomposition products are separated in a decomposition separation (distillation) column 11 to produce various hydrocarbons. Fractions are obtained which leave the separation column in the usual manner. full range or Light cut light cycle oil (FRLCO or LCLCO) from separation column 11 The hydrotreater 1 is extracted through the extractor pipe 12 and serves as the first stage of the hydrocracker. Send to 5. The feed is hydrotreated in unit 15 to remove aromatic saturation and residual Hydrogenation of heteroatoms, especially nitrogen and sulfur, these heteroatoms In the interprocess separator 16, it is removed along with excess hydrogen as ammonia and hydrogen sulfide. The hydrogen is returned to the hydrogen circuit line 17 after purification. Separation between processes Although gas purification is not necessarily required, it is shown as an optional example. Hydrotreated The cycle oil then passes through the second stage of the system, hydrocracker 18, where it is opened. Ring reaction and decomposition occur, hydrogenation rich in monocyclic aromatics within the gasoline boiling range Decomposition products are formed. After separating the hydrogen in separator 19, the hydrocracker stream The output is separated in a conventional manner in a distillation column 20 to form dry gas, gasoline, middle distillates and A product containing a residual oil fraction is formed, which is extracted and reduced to a low sulfur oil. Mixed with fuel oil or optionally passed through recycle pipe 21 to FCCUlo. May be recirculated. The gasoline range product obtained from column 20 has a high octane number. Directly without rehoming or other treatments to increase octane Suitable for blending into refinery gasoline product pools.

The monofunctional catalyst used in the hydrogen cracking process of the present invention has an unexpectedly long operating cycle. However, the cycle is the same as that of a normal hydrocracking operation (typically 6 months). ~1 year) may not be that long, so periodic or continuous catalyst regeneration methods may be used. It is desirable to Catalyst regeneration should be carried out in a fixed bed, swing reactor. Can be done. In this type of equipment, two reactors are loaded with hydrocracking catalysts. , passing the liquid through a hydrofining reactor and then into one of two hydrocracking reactors. of the second reactor At the end of the cycle, e.g. at the end of 30 days, the stream can be transferred to another hydrocracking reaction. Regenerate the reactor containing the aged catalyst. Repeat this step for one Continue operating one hydrocracking reactor while simultaneously regenerating the other.

Another regeneration method involves operation in a moving bed or fluidized bed hydrocracking reactor and some of the catalyst Continuous catalyst regeneration method by withdrawing from the reactor and regenerating it in a separate vessel It is. The hydrocracker is of a construction similar to that shown in U.S. Pat. No. 4,797,478. The patent describes the production of methanol using continuous catalyst regeneration in a separate vessel. A fluidized bed reactor is described for the conversion of to hydrocarbons.

Whether using a swing reactor or continuous regeneration, the cycle life is Operate under conditions such that the life span is at least 5 days, preferably at least 10 days. is preferable. In fluidized bed operation, catalyst inventory (i nve It is desirable to regenerate only a small amount of the catalyst. Regenerators are generally separated It requires a container and an air compressor, deactivates the catalyst at a rapid rate, and requires very large regeneration. There is a substantial economic disadvantage if living facilities are required. Economically adverse effects Do not expose the catalyst to excessive heat or water vapor which will cause hydrothermal damage to the zeolite. This is alleviated by the need to perform regeneration in a way that avoids Therefore, the catalyst is It is desirable not to have a fast deactivation rate.

Similarly, in the operation of a swing reactor, the pause times taken during regeneration Again, long cycle life is desired as equipment capacity is reduced. Yes.

Unexpectedly long cycle duration achieved despite the absence of metal components This fact is due to the nature of the method of the present invention. Preferred light cycle oil feed Since the PNA coke precursor contains a limited amount of high molecular weight PNA coke precursor, Even at low hydrogen pressures, coke formation is minimized. In addition, hydrocracking The initial hydrotreating stage of the medium is sufficient to eliminate the need for metal functionality in the second stage. causes a certain degree of hydrogenation. To maintain the longest cycle duration, hydrogenation The cracking catalyst must be selected for minimal kneeking and for this purpose For this purpose, Y zeolite, especially USY, is preferred. Additionally, low sodium content is desired. Preferably, this can be achieved by continuous ammonium exchange followed by calcination. will be accomplished.

A pre-hydrotreatment step before hydrocracking saturates polynuclear aromatics (PNAS) and Preferred for removing impurities including nitrogen and sulfur. The majority of PNAS It is found in the high-boiling part of oil oil, along with most of the heteroatoms, and is therefore hydrotreated. The stage is carried out at a low hydrotreating stage degree in the case of light-cut LCO feeds. obtain.

The objective of the hydrocracking process is to remove aromatic to high octane monocyclic compounds in the feed. It is to produce aromatics. Feeds include naphthalene, benzothiophene, etc. Since it contains mainly cyclic aromatics, the degree of saturation during the hydrocracking step is determined by the completeness of these components. Must be limited to avoid total hydrogenation. For this reason For this purpose, relatively low to moderate hydrogen pressures are used, typically 7000 kPa (10 00 psig), the minimum pressure is typically 2860 kPa (400 psig) Typical pressures range from 4250 to 7000 kPa (600-1000 psig). It is surrounded. The exact pressure depends on the feed characteristics (aromatic and heteroatom content), reserve water selected according to the treatment, catalyst stability and aging resistance and desired product properties. It will be done. Similarly, ring-opening reactions must be limited to preserve the aromatic properties of gasoline products. Therefore, the severity (temperature, residence time, conversion rate) is also limited. 195℃- (385°F-) Conversion to gasoline is less than 80% by volume, preferably 65% by volume. Must be less than %. Conversion rates may exceed 75% by volume; A typical maximum value is 55-70% by volume. Optimum conversion rate means best product for octane, from 20 to 50, for example from 20 to 30% by volume. Fi The absence of heteroatoms and PNAS from the and PNA-induced inhibition and catalyst deactivation due to coke deposition. This reduces the need to relate conversion to hydrogen pressure in the LCO feed (U.S. (See Patent No. 4,738,766). However, in the case of a full range feed, The conversion rate is preferably as described in U.S. Pat. No. 4,676,887. Must be limited to no more than 1/20 of the hydrogen partial pressure expressed in psig. No. 2860-7000 kPa (400 kPa) for conversion rates up to 70% by volume ~1000 psig), typically 4250-7000 kPa (600-1000 psig) Pressures in the range sig) are preferred. Hydrocracking temperatures are typically up to 450° C (850°F), but higher temperatures up to 480°C (900°F) are also used. , typically the minimum temperature is 315°C (600°F) or higher, e.g. 370°C. (700°F) is the preferred minimum value. The space velocity is determined by the desired temperature and conversion. Depending on the level, typically 0.25-2.5/hour, more commonly , 0.5-1,5/h (LHSV, 20°C). Hydrogen circulation rate is 90-9 00n, 12. (!, -’(500-5000 S CF/BbQ) is suitable. Ru. The heat for the endothermic cracking reaction is readily supplied from the exothermic hydroprocessing stage feed; This factor, along with the fact that low coke formation is obtained, is favorable. In some cases, it eliminates the need for continuous regeneration and allows fixed bed operation.

A notable feature of the process of the invention is the low hydrogen consumption during the hydrocracking stage.

Compared to methods carried out under similar conditions using conventional trifunctional hydrocracking catalysts, , the hydrogen consumption is significantly lower, especially at high conversions. In fact, normal hydrocracking Contrary to technology, hydrogen consumption decreases as conversion increases. Conversion rate (4 20'F+, 215℃) exceeds 20% by volume, 230n,Q,ρ,-'( Hydrogen consumption of less than 1300 SCF/Bb12) is easily achieved and conversion rate (42 0°F+, 215°C) at 20-40% by volume, 214n, 12.12. -’(12 Hydrogen consumption of less than 00 SCF/Bb is achieved.

As mentioned above, two-stage hydrocracking is used, i.e., hydrotreating followed by hydrogen cracking. This is not desirable for light cut feeds, but it is true for all feeds. is preferred, and in practice is preferred for high boiling point feeds, e.g. full range cycle oils. is necessary. Hydrotreating is a process in which the feed has a relatively high heteroatom content. In-process separation of inorganic nitrogen and sulfur can reduce the cycle life of the It is useful because it prolongs your life. The hydrocracking process is used for pre-hydrogenation treatment. Inter-process separation may or may not be performed beforehand. Eliminate separation between processes and use a fixed bed When employing cascade operation in the reactor, the hydroprocessing catalyst is simply added to the reactor. It may be installed on top of the hydrocracking catalyst.

The hydroprocessing catalyst can be any suitable hydroprocessing catalyst, many of which are commercially available. available at. These are usually metals or golds with hydrogenation/dehydrogenation activity. Relatively inert, i.e. non-acidic, with large pores (>0,002μm) Consists of a combination of refractory carriers.

Suitable supports are alumina, silica-alumina or silica and hydrocracking catalysts. Other amorphous large pore amorphous solids as mentioned for binder materials It is. Suitable metal components include nickel, tungsten, cobalt, molybdenum, Vanadium, chromium, often cobalt-molybdenum, nickel-molybdenum or two.

It is a combination of the above-mentioned components such as keruf bartomolybdenum. Other periodic table ■ Metals from Groups 1 and 2 can also be used. Approximately 0.1-20% by weight, usually 0.1 ~10% by weight metal is typical.

The catalyst is relatively non-acidic (some acidity is required for the opening of the heterocycle to remove the heteroatom). ), and since the temperature is relatively low, the conversion rate during hydrotreating is low. It is relatively low, typically less than 10% by volume, and in most cases less than 5% by volume. warm The temperature is usually 315-425°C (600-800°F), often 330-400°C. (625-750'F). Space velocity (LHSV at 20°C, liquid space velocity) is usually 0.25 to 4.07 hours, preferably 0.4 to 2.5 hours, and is strictly The dense selected space velocity depends on the desired degree of hydrotreating and the selected operating temperature. Depends on. Hydrogen pressure is 1,500 to 7,000 kPa (200 to 1,000 psig ), preferably 2860-5620 kPa (400-800 psig) is typical The hydrogen circulation rate is 90-900n, I2. Q, -'(500~5000SC F/Bb12) is suitable. When using a cascade operation, the hydroprocessing pressure is Because of the bed pressure drop, the pressure is slightly higher than desired in the hydrocracking process.

Hydroprocessing catalysts, like hydrocracking catalysts, can be fixed, fluidized or moving bed catalysts. However, downflow fixed bed operation is preferred because it is simple.

When prehydrotreating is adopted, the conditions of the hydrocracking stage are appropriately adjusted to achieve the desired results. To achieve the desired overall process objective, i.e., to form a high octane gasoline boiling range product. maintains incomplete aromatic saturation with limited ring opening of the hydroaromatic components. . Therefore, naphthalene, methylnaphthalene and benzothiophene are When carrying out some degree of saturation of bicyclic aromatics such as is less for the same throughput in the second stage) Hydrogen consumption in the hydrocracking process volume is reduced so that the temperature will be lower if the space velocity is held constant. place Space velocity is correspondingly reduced to maintain the desired conversion level (temperature dependent) Sometimes it is necessary to do so.

As mentioned above, the purpose of the method of the present invention is to directly produce high octane gasoline. It is. The boiling range of gasoline is typically C6-196°C (Cs3B5°F). ) (end point), but the end point for gasoline may be lower depending on the product specifications used. For example, C, -165°C (C, -330° FX end point) or C5-232°C (cs-450'F). lowest objective o The cutane number is just 85 or more, for example 87 (RON+O). Ta In most cases, a higher octane rating, e.g. at least 90 net , for example, 95. In suitable cases, octane ratings of 100 or higher can be achieved. Wear. In all cases, gasoline boiling range products may be used for reforming or other Directly mixed into refinery gasoline boule without any treatment to improve octane can. As mentioned above, the residual oil fraction of the hydrocracker is recycled to the catalytic cracker, Here, the improved degradability as a result of the increased hydrogen content further reduces the total gas Phosphorus yield is improved, in this case due to increased yield from the cracker. Hydrocracking Equipment residual oil is used in conventional CHD equipment to form fuel oil or diesel fuel, for example. After hydrotreating in It is also possible to recirculate the combined stream to the FCCU as described above. The method of the present invention allows high aromatic production directly from the highly aromatic products obtained from the catalytic cracker. It is noteworthy as a method of producing Kutane gasoline. Low water in hydrocracker This result and low hydrogen consumption by using bare pressure and moderate processing conditions Quantity and reduced utility needs can be achieved.

The invention is illustrated by the following examples.

cold storm yyu Light cycle oil obtained from a fluid catalytic cracking operation was used as feed. This is the first It had the following properties shown in Table 3.

Table 3 LCO Hydrocracking Feed The feed was heated to 355°C (675°F) and 4240 K Pg (600 psig). At HS (inlet), commercially available NI Mo/AQxOs hydrogenation catalyst, hydrogenation No metal components are added to the catalyst for ILH8V and hydrogenation function. Using silica-bonded steamed ultra-stable Y zeolite as a hydrocracking catalyst and subjected to two-stage cascade hydrotreating/hydrocracking (no separation between steps).

The properties of the hydrocracking catalyst were as shown in Table 4 below.

Table 4 Hydrogen chemical decomposition was carried out for 38 days, hydrogen inlet pressure 4240 kPa (600 psig), 1/2 17) LH3V and 365°C (690°F) to 430°C (8100F) The conversion was carried out at a temperature in the range of 20% by weight (196°C - (385°F -) Solin) was kept constant. Catalyst aging is a function of the temperature required to maintain a specific conversion. This was tracked by plotting the degree.

The results are shown in Figure 2. End of cycle (EOC) temperature 425”C (80 0°F) was reached after only 30 days.

The properties of the product are as follows with a TO5 (total number of distribution days) of 12 days.

Table 5 Hydrogenolysis products From the above results and Figure 2, it is clear that the dealkylation process for high-octane gasoline products is It can be seen that monofunctional catalysts can be used for the decomposition of the

Examples 2-4 Three additional experiments were performed to compare the performance of the two-catalyst and one-catalyst systems. . A two-catalyst system has a hydroprocessing function and a hydrocracking function in two individual catalysts. consisting of an unpromoted tJsY catalyst and a hydroprocessing catalyst to separate. -Catalyst system In order to provide both hydrotreating and cracking functions, NiMo-promoted U SY was used.

In the experiment, light-cut Co was used as the feedstock as shown in Table 6. there was. The properties of the catalyst are shown in Table 7. In this summary, HDT is a commercially available NrMo / A (refers to 2t Os hydrotreating catalyst, USY refers to non-promoted USY catalyst, and and NiMoUSY are NiMo types of USY catalysts. USY before addition of metals and N iMo U S Y catalyst extrudates were steamed to an α of 55. .

Table 6 Properties of feedstock - Light cut LCO Note) (1) Before metal addition (2) Set α to 65 by steaming, and conduct three experiments measured before metal addition. I did it like that. Examples 2 and 3 used a two-catalyst system, and Example 4 used a single-catalyst system. Ta. Regarding Examples 2 and 3, the hydrotreating catalyst and the USY catalyst were They were placed in separate reactors at a quantitative ratio of 50150, and H, S and NH were separated during the process. I operated it in cascade mode without using it. During the experiment, U was used to cover a wide range of conversions. The SY catalyst temperature was varied while the hydrotreating catalyst temperature was varied in Examples 2 and 3. They were held constant at 610°F (320'C) and 685°F (365°C), respectively.

Detailed experimental conditions are summarized in Table 8 below.

Table 8 The results are shown in Table 9 below and in Figures 3 and 4. Table 9 shows certain conversions. Figures 3 and 4 show the distribution of carbon number 4 hydrocarbons at the The gasoline product octane (R10) and hydrogen consumption at the conversion level are respectively Show.

The results revealed that, surprisingly, the HDT/USY catalyst system (Examples 2 and 3) higher octane number ( -R〇　) was found to be produced. (Note 2 The conversion rate is 21 215°C+(420'F-) in the feed which is converted to 5°C-(420'F-) material. ”) defined as the percentage of the substance.) At equal conversions, HD T/U S With the Y catalyst system, slightly more 01-C4 light gas is obtained. However, HDT The C4 hydrocarbons produced from the /USY catalyst system (Examples 2 and 3) were High in sobutane and butenes, they can be directly mixed into the alkylation feed and further gas Phosphorus yield can be increased. Table 9 above shows the number of carbon atoms for the three examples. The stream compositions of No. 4 are compared.

The total isobutane and butene concentrations for Examples 2 and 3 were This is over 80% compared to 5%.

Furthermore, in the HDY/USY catalyst system, as shown in Figure 4, especially at high conversion rates, , the amount of hydrogen consumed is smaller than that of the NiMoUSY catalyst.

0° 8 Evening Q C5-420・F octane, R+0 tk)’K It, SCF/B International Search Report

Claims (15)

[Claims] 1. Hydrogen partial pressure 7000 kPa or less and conversion rate to gasoline boiling range products 5 In the presence of hydrogen and a solid porous monofunctional acid-type decomposition catalyst at 5% by volume or less, Boiling point at least 149°C, end point at most 399°C, aromatic content at least Highly aromatic with a hydrogen content of 50% by weight or less and a hydrogen content of 12.5% by weight or less Production of gasoline comprising hydrocracking a killed hydrocarbon feed Construction method. 2. Claim 1, wherein the aromatics content of the feed is at least 60% by weight. The method described in Section 1. 3. Claims 1 and 5, wherein the hydrogen content of the feed is 8.5 to 12.5% by weight. or the method described in Section 2. 4. Claim 1, 2 or 3, wherein the feed has an API gravity of 25 or less. is the method described in Section 3. 5. Claims 1, 2 and 2, wherein the hydrogen partial pressure is 600 to 1000 psig. The method described in Section 3 or Section 4. 6. Claims in which the conversion rate is 0.05 times or less of the hydrogen partial pressure expressed in psig. The method according to any one of items 1 to 5. 7. Claims 1 to 6, wherein the end point of the feed is above 343°C and at most 399°C. The method described in any of the paragraphs. 8. The claimed hydrocracking catalyst is a large pore crystalline aluminosilicate zeolite. The method according to any one of Ranges 1 to 7. 9. Zeolite is Zeolite Y, Zeolite USY, or Zeolite Do- 9. A method according to any of claims 1 to 8, comprising Aly. 10. Claims 1 to 9, wherein the hydrogenolysis is carried out at a temperature of 371 to 454°C. The method described in any of the following. 11. Any one of claims 1 to 10, wherein the zeolite has an α value of 100 at most. The method described in. 12. The hydrocracked gasoline boiling range product has an octane number of at least 87. (RON+0) The method according to any one of claims 1 to 11. 13. Claims 1 to 12, wherein the feed is hydrotreated before being hydrocracked. The method described in any of the paragraphs. 14. Claims where the conversion to gasoline boiling range products is between 20 and 50% by volume. The method according to paragraph 13. 15. Hydrogen consumption at a conversion rate (above 216°C) of at least 20% by volume is 2 31n. l. l. 15. The method of claim 14, wherein the value is less than -1.