KR860001880B1 - Process for making naphihenic lubeestocks from raw distillate - Google Patents

Abstract

Low pour pt. luke oil base stocks are produced from raw distillate fractions(I) derived from marginal naphtheric crudes; (I) have boiling range 260-566≰C, pouring point below 2≰C, API gravity 20-25, naphthene content 25-40 wt.% and paraffin content below 50 wt.% by contacting(I) at 260-357≰C with an alumino silicate zeolite catalyst(silica/alumina ratio above 12 and constraint index of 1-12) and hydrogen. The prod is made by contacting at 1480-13890 KPa. The lube oil has a pouring point below minus 23≰C.

Description

Manufacturing method of naphthenic lubricant base

The present invention relates to a method for producing a naprene lubricating oil substrate from distillate raw materials by mixed hydrogen desoldering / hydrogenation.

In the present invention, an oil of 260 ° to 357 ° C. (500 ° to 657 ° F.) is brought into contact with a telephone catalyst containing an aluminosilicate zeolite having a silicon / alumina ratio of 12 or more and a limiting index of 1-12, and 260 ° to 357 ° C. Lubricating oils with a pour point below -23 ° C (-10 ° F) after hydrotreating the product at 0 ° C (500 ° -657 ° F) and 1480-13890 KPa (200-2000 psing) with a hydrogenation catalyst containing a hydrogenated component in a non-acidic support By recovering from the naphthenic product, having a boiling point of 260 ° -566 ° C. (500 ° -1050 ° F.), 25-50% by weight aromatics, 25-40% by weight naphthene, up to 50% by weight. Provided is a method for producing a low flow point lubricating oil base from a raw distillate containing paraffin, a pour point of 2 ° C. or less and paraffin of 50% by weight or less.

Raw distillate fractions obtained from less valuable "naphthenic crude products" are not used to produce high lubricating oils or high flow point naphthenic lubricants with a high viscosity index (V.I.). Since the raw material thickener fraction has a low paraffin content and hardly produces a purified raw material having a viscosity index of about 60 or more, it is not suitable for producing a lubricant having a high viscosity index. The distillate fraction is not suitable for the production of naphthenic lubricants in conventional solvent dewaxing devices, since no solvent dewaxing technique is available for producing oils with low flow points (<-23 ° C.) (<-10 ° F.). not.

The wax content in the crude product is a typical crude product used to make naphthenic lubricating oil and is 40% of the Chanis Taching Crude or Utah Altamonte crude product at less than 1%, such as the Coastal Low Pour crude product. Varies widely.

The present invention is directed to hydrogen desorption at a pour point of -23 ° C. (-10 ° F.) over a ZSM-5 catalyst and to obtain the desired product and to maintain the pour point below -23 ° C. (-10 ° F.). It relates to reforming a naphthenic distillate fraction with a low wax content into a naphthenic lubricating oil raw material by the mixing process added.

The feedstock of the present invention is described as a distillate fraction derived from a less valuable naphthene crude product and having a boiling point of at least 260 ° C. (500 ° F.). Low-value naphthenes refer to oils belonging to "intermediates" that are too high in wax and cannot be classified as "naphthenes" and are classified according to the mineral bureau's classification method.

The classification of mineral stations consists of determining the share of the two main non-occupants of the crude product shown in the following table.

Table 1

Class B analysis

Mineral sphere classification of all raw materials

(Ministry Bureau Report No. 3279)

Criteria: Specific gravity of two "key" oils

Key oil 1 second 265 ° C (505 ° F) medium boiling point 250-275 ° C (482-527 ° F)

Specific Gravity, ° API Raw Material

> 40.0 paraffin

> 33-40 intermediate

<33.0 naphthenes

Key Oil No. 2, 406 ° C (762 ° F) Medium Boiling Point 391-420 ° C (736-788 ° F)

Specific Gravity, ° API Raw Material

> 30.0 paraffin

20-30 intermediate

<20.0 naphthenes

The specific gravity of "non" fraction 1 is the first criterion used for classification, and the specific gravity of "key" fraction 2 represents the second criterion. If the two criteria are the same, only one is used to classify the raw material.

High specific gravity (low API specific gravity) refers to condensed molecules, such as naphthenes and aromatics, where low specific gravity represents long ring paraffins. The specific gravity of these two key fractions determines paraffin intermediate or intermediate naphthene. More importantly in the present invention, the specific gravity of the second key fraction determines the paraffin intermediate or intermediate naphthene. More important in the present invention is the specific gravity of the second key fraction. It should be 20-25API. Naphthenic oil having an API specific gravity of 20 or less second key fraction is suitable as a raw material for the prior art. The 25 API or more is not good for producing naphthenic raw materials because of poor lubricating oil yield and quality.

Naphthenic lubricants are the main components of certain oils and greases such as transformer oil and refrigerator oil. These represent a large proportion (over 25%) of all lubricating oil products. Since the supply of naphthenic raw materials is depleted, alternative raw materials are needed. One of the important objects of the present invention is to satisfy this need.

It is another object of the present invention to use all catalyst systems for lubricating oil production to replace solvent purification such as aromatic extraction or acid treatment.

In recent years, techniques for deleading petroleum raw materials as catalysts have been used. The method developed at the British Petroleum Institute is described in The Oil and Gas Journal, pp. 69-73, issued June 6, 1945. See US Pat. No. 3,668,113.

US Pat. No. 28,398 describes a process for desoldering with a catalyst containing zeolite ZSM-5. A mixture of catalytic hydrotreating processes is described in US Pat. No. 3,894,938.

However, in most catalytic dewaxing processes, the raw materials are high in paraffin, since these paraffin base stocks or oils contain undesirable components that must be removed by the dewaxing process. These materials are not usually used in naphthenic raw materials because viscous fractions with low chain paraffin content and inherently low pour point are produced by distillation. (Ie, see US Pat. No. 4,137,148). At the same time, naphthene raw materials are not introduced into the dewaxing process as shown in US Pat. No. 4,176,050. This is because the substance does not contain much paraffin.

As described above, the novel process of the present invention is distillate fraction of low value naphthenic raw materials having a boiling point of 260 ° -566 ° C (500 ° -1050 ° F). Low value naphthenic raw materials are defined similarly to the classification of mineral stations. The method consists of distilling 391 ° to 420 ° C. (736 ° to 788 ° F.) of the non-occupied fraction from the raw material and then measuring the specific gravity of the distillate. Distillates of low value naphthenic raw materials should have an API specific gravity of 20-25. Distillate fractions of various low value naphthenic raw materials differ in chemical composition and contain 25-50% aromatics, 25-40% naphthenes and up to 50% paraffins. They have a low wax content and have a pour point below 2 ° C (35 ° F). The novel method of the present invention does not require a solvent extraction step, so that the naphthenic material is subjected to a temperature of 260 ° -357 ° C. (500 ° -675 ° F.), a space velocity of 0.1-10 per hour and 1480-13890 KPa (200-2000 psig). It is carried out by introducing into the catalytic conversion process carried out at hydrogen pressure.

The inversion catalyst is a complex composed of a hydrogenated metal (preferably Group 8 metal), an acid of aluminosilicate zeolite having a silica / alumina ratio of 12 or more and an inhibition index of 1-12.

An important feature of the crystal structure for this kind of zeolite is to provide an exit and suppression from the internal crystalline glass space having a pore size and pore window of about 5 ° C. or more, as provided by the 10-melt ring of oxygen atoms. . Of course, these rings are formed by the normal positions of tetrahedera to supplement the anionic structure of crystalline aluminosilicates, and oxygen atoms are bonded to silicon or aluminum atoms at the center of the tetrahedral. The form is of composition whose molar ratio of silica to alumina is at least about 12 and the structure provides a similar suppression dimension to the crystalline free space.

The silica ratio to alumina can be determined by conventional analytical methods. This ratio indicates that it is most similar to the ratio in the solid anionic structure of zeolite crystals, excluding aluminum in the cation or other form or binder in the channel. Although zeolites having a ratio of silica to alumina of at least 12 are useful, it is preferable to use zeolites having a high cost of at least about 30. This zeolite has an internal crystal absorption capacity of normalheptane larger than water after activation. That is, they have "hydrophobicity". This hydrophobicity is believed to be good in the present invention.

The zewarite type useful in the present invention freely absorbs normal hexane and benzene and has a pore size of about 5 ° or more. In addition, the construct must provide inhibitors similar to larger molecules. Regardless of the presence of such an inhibitory approach, it can be judged from known crystal structures. For example, if the pore window in the crystal is formed by an eight-membered ring of oxygen atoms, access by molecules of cross sections larger than normal hexanes is excluded and zeolites do not have the desired shape. The 10-membered window is good. In some cases, excess puckering or hole blocking can make these zeolites ineffective. Although the perkered structure is present as a TMA oprelite known as an effective zeolite, the 12-membered ring does not provide enough inhibitor to cause a favorable conversion. In addition, the structure may be operated due to hole blocking or other causes.

Rather than judging from the crystal structure whether or not zeolites have the necessary inhibitors, a simple determination of the "inhibition index" is based on the following method, using a mixture of normal hexane and 3-methylpentane in samples of approximately 1 g of catalyst at atmospheric pressure It can be produced by passing continuously. Zeolite samples in the form of flaky or extrudates are ground to rough sand and placed in glass tubes. Zeolites are treated with air at 538 ° C. (1000 ° F.) for at least 15 minutes before testing. The zeolite is flushed with helium and the temperature is adjusted from 288 ° to 510 ° C. (550 ° -950 ° F.) to achieve a 10-60% total conversion. The mixture of hydrocarbons is passed over a zeolite at a space velocity of 1 per hour (i.e., 1 volume of liquid hydrocarbon per volume of zeolite per hour) while diluting with helium to bring the molar ratio of helium to total hydrocarbon 4: 1. After 20 minutes in the fluid, a sample of the effluent is taken and conveniently analyzed for gas chromatography to determine the fraction that remains unchanged for each of its hydrocarbons.

The "inhibition index" is calculated as follows:

The inhibition index is similar to the constant decomposition rate for both hydrocarbons. Zeolites suitable for the present invention have an inhibition index of about 1-12. The inhibition index (Cl) for typical zeolites is

The inhibition index represents a specific zeolite but is an accumulation of various variables used in the determination and calculation. As such, for a given zeolite, depending on the temperature used within the 288-510 ° C. (550 ° -950 ° F.), converted to 10-60%, the inhibition index may vary within about 1-12. Similarly, the presence of various substances, such as the crystal size of zeolites, the absorbed debris, and the intimate mixture of zeolites can affect the inhibition index. Thus, those skilled in the art provide a useful way to characterize zeolites, taking into account the crystallization method along with the possibility of mixing various materials. However, in all cases the inhibition index at temperatures within 288 ° -510 ° C. (550 ° -950 ° F.) has a value of about 1-12 for a given zeolite.

The grade of zeolite specified here is demonstrated by ZSM-5, ZSM-11, ZSM-12, ZSM-35, ZSM-38 and other similar materials. U.S. Patent No. 3,702,886 describes ZSM-5, U.S. Patent No. 3,832,449 describes ZSM-12 and U.S. Patent No. 4,046,859 describes ZSM-38. This zeolite can be identified in the molar ratio and anhydrous state of the oxide as follows:

(0.3-2.5) R ₂ O: (0-0.8) M ₂ O: Al ₂ O ₃ :> × SiO ₂

Wherein R is an organonitrogen-containing cation derived from a 2- (hydroxyalkyl) trialkylammonium compound, M is an alkali metal cation and is characterized by a particular X-ray powder diffraction form.

In a preferred synthetic form these zeolites have the following structural formulas as molar ratios of oxides and anhydrous states as follows.

(0.4-2.5) R ₂ O: (0-0.6) M ₂ O: Al ₂ O ₃ : XSiO ₂

Wherein R is an organonitrogen-containing cation derived from a 2- (hydroxyalkyl) trialkylammonium compound, alkyl is methyl, ethyl or a mixture thereof, M is an alkali metal (especially sodium) and X is 8- 50.

Synthetic ZSM-38 zeolites have a finite distinct crystal structure, the X-ray diffraction pattern of which represents the large lines shown in Table 2. This X-ray diffraction pattern (large line), natural ferrilite form, is similar to natural ferrierite except that it shows a large line at 11.33A.

The characteristics of ZSM-38 increase the absorption capacity of 2-methylpentane in zeolite when compared to the hydrogen form of natural ferrierite obtained by calcining the ammonium exchange form (n-hexane by n-hexane / 2-methylpentane ratio). Compared to absorption). After calcining at 600 ° C., the absorption ratio of n-hexane / 2-methylpentane to ZSM-38 is 10 or less and the ratio to natural ferrilide is 10 or more (Example 34 or more).

Zeolite ZSM-38 is a source of alkali metal oxides (preferably sodium oxide), a source of organic nitrogen-containing oxides, aluminum oxide silicon oxides and water and a solution having the following composition and then maintaining the mixture until crystals of zeolites are formed: Properly prepared by:

Wherein R is an organic nitrogen-containing cation derived from 2- (hydroxyalkyl) trialkylammonium compound and M is an alkali metal ion. (The amount of OH ⁻ is calculated only from the inorganic source of alkali without providing any organics. The crystals are then separated and recovered from the liquid. Typical reaction conditions are from 90 ° -400 ° C. for 6 h-100 ° C. Heating is preferably performed at a temperature of 150 ° -400 ° C. with a time period of from 6 hours to 80 days.

Digestion of the gel particles is also carried out until crystals are formed. The solid product is separated from the medium by cooling the whole to room temperature, filtration and washing. The crystal product is dried at 110 ° C. (230 ° F.) for 8-24 hours.

When prepared in the presence of organic cations, the zeolites are catalytically unstable because the internal crystal free space is occupied by the organic cations of the forming solution. They can be activated by base exchange with ammonium salts by heating in an inert atmosphere at 538 ° C. (1000 ° F.) and then calcining in air at 538 ° C. (1000 ° F.). The presence of organic cations in the solution formed is not necessary for the preparation of the zeolites of the present form, but is advantageous for preparing certain types of zeolites. In particular, it is generally desirable to activate by calcining in an air at about 538 ° C. (1000 ° F.) for 15 minutes-24 hours after base exchange with an ammonium salt.

Natural zeolites can be converted to this type of zeolite catalyst by various activation methods and other treatments (base exchange, steam treatment, alumina extraction and calcination). Natural minerals that can be treated are ferrierite, brusterite, stilbite, dichiriteite, epistilbite, ullandite and crinophthylite. Preferred crystalline aluminosalates are ZSM-5, ZSM-11, ZSM-12, ZSM-35 and ZSM-38 with ZSM-5 being particularly good.

In a preferred embodiment of the invention, the zeolite is selected as having a crystal structure density of about 1.6 g / cm 3 in dry hydrogen form. Zeolites satisfying all three of these criteria were found to be most preferred. Therefore, preferred zeolites of the present invention are those having an inhibition index of at least about 1-12, a silica / alumina ratio of about 12 and a dried crystal density of at least about 1.6 g / cm 3. The dry densities of known structures can be found in pages 19 to 1000 of the literature on zeolite structures by W. M. Meyer, published in "Proceedings of the Conferencd on Molecular Sieves, London, April 1967", published in 1968 by the Institute of Chemical Engineers, London. It can be calculated from the number of silicon and aluminum atoms per cubic angstrom. When the crystal structure is unknown, the crystal structure density can be determined by conventional picknome technique. For example, it can be determined by immersing the dry hydrogen form of zeolite in an organic solvent that is not absorbed by the crystal. The stability and specially maintained activity of these zeolites may be consistent with the high crystalline anionic structure density of about 1.6 g / cm 3 or more. Of course, these high densities must be matched with relatively few free spaces within the crystals, which can result in a more stable structure. However, this free space is important as a catalysis.

The crystal structure density of some typical zeolites is as follows:

When synthesized in the alkali metal form, zeolites are conveniently converted to hydrogen by the production of ammonium intermediates as a result of ammonium ion exchange and by calcination of ammonium to form the hydrogen form. In addition to the hydrogen form, other forms of zeolite with reduced original alkali metals of about 1.5% by weight or less can be used. As such, the native alkali metal of the zeolite can be replaced by ion exchange with ions of a suitable group of IB-VIII metals (eg nickel, copper, zinc, palladium, calcium or rare earth metals).

In carrying out a preferred conversion process, it is preferred to mix the crystalline aluminosilicate zeolite with other metals resistant to the temperature and other conditions used in the process. Such matrix materials include synthetic or natural materials as well as inorganic materials (eg, clays, silicas and / or metal oxides). The inorganic material may be naturally present or in the form of a gel containing gelatinous precipitates or mixtures of silica and metal oxides. Natural clays that can be mixed with zeolites include montmorillonite and kaolin varieties, which are semibentonite and Dixie, McNamee-Georgia and Florida viscose or major inorganic constituents. Kaolin, known as citrine, kaolinite, decite, nacrite, or other clays that are annocite.

In addition to the above materials, the zeolites used herein are not only porous matrix materials (e.g., alumina, silica-alumina, silica-magnesia, silica-zirconia, silica-toria, silica-berilia, silica-titania), but also ternary compositions (e.g. Silica-alumina-toria, silica-alumina-zirconia, silica alumina-magnesia and silica-magnesia-zirconia) The matrix can be present in the form of cogel The ratio of zeolite component and inorganic oxide gel matrix Silver can vary widely with a zeolite content of 1-99% by weight, in particular 5-80% by weight.

The first stage effluent comprising hydrogen is introduced into a hydrotreating reactor of the type commonly used to process lubricant raw materials. The distillation operation necessary to remove the hardened product to match the combustion and flashpoint can be carried out between the dewaxing and hydrotreating steps. However, the cascade type operation is good to avoid the need for refilling and separation of hydrogen with the intermediate distillate because it forms a less stable product in the middle distillation and / or low volumes.

A known hydrotreating catalyst composed of a hydrogenation component on the non-acidic support may be used. For example, cobalt-molybdate or nickel-molybdate or molybdenum oxide on an aluminum support. Here, temperature control is required to produce the higher product, and the hydrotreater is maintained at a pressure of 1480-1389 KPa (200-2000 psing) and 260 ° -357 ° C. (500 ° -657 ° F.).

When a good cascade type is used, the effluent of the hydrotreater is ejected on the tower by distillation. That is, most of the volatiles are removed to satisfy the flash and flash point.

EXAMPLE

The raw distillate is obtained from the Venezuela Melon feedstock by vacuum distillation to produce 288 ° -416 ° C (550 ° -780 ° F) fraction. Polymer mass spectral analysis revealed that it contained 30% aromatics, 30% naphthenes and 30% paraffins.

The distillate is treated with ZnHZSM-5 and its preparation is described in US Pat. No. 28,398 under the following conditions.

Pressure 3549 KPa (500 psing)

LHSV 1

Temperature (SOC) 304 ° C (580 ° F)

H ₂ circulation 445 Nl / l (2500SCF / B)

The conversion product consists of 3% by weight gas product containing 0.3% by weight of dry gas (ethane and lighter substances), 1.2% by weight of propane and 1.5% by weight of butane and 97% by weight of Cs + liquid product. Fell out. The liquid product is 6.9% by weight of C ₅ -to 166 ° C (330 ° F) naphtha, 3.1% by weight of 166 ° to 288 ° C (330-550 ° F) diesel fuel and 87% by weight of 288 ° C based on the packed distillate Consists of + (550 ° F) liquid. The 288 ° C. + (550 ° F.) liquid has a pour point of −51 ° C. (−60 ° F.) and the following composition: 32.3 wt% aromatics, 31.5 wt% naphthene and 36.2 wt% paraffin.

18 g of 288 ° C. + (550 ° F.) liquid was dissolved in 10 ml of hexane in hexane and then introduced into a 300 ml stirred autoclave with 11 g of reduced Harshaw Ni diatomaceous earth; Compressing with hydrogen heated to 316 ° C. (600 ° F.) to 3549 KPa (500 psing) with stirring for 2 hours and then cooling; The floated hydrogenated liquid was filtered to remove the catalyst and remove the cyclohexane solvent. The properties of the product are shown in the following table:

Specific gravity (at 16 ° C) 0.88 KV (at 99 ° C), CS 2.5

Pour point, ° C (℉) -51 (-60) Viscosity index 40

KV (at 38 ° C.), CS 11.0

Mass spectrometric analysis of the hydrogenated product revealed that it contained 23 weight percent aromatics, 41 weight percent naphthenes and 35 weight percent paraffins.

Claims (5)

Low value nap containing 25-50% by weight aromatics, 25-40% by weight naphthenes, up to 50% by weight paraffin, with a pour point of 2 ° C or less, API specific gravity of 20-25, and a boiling point of 260-566 ° C. In the process for producing a low flow point lubricant base from distillate fraction distilled from TEN crude oil, the presence of hydrogen to which an inversion catalyst containing an aluminosilicate zeolite having a silica / alumina ratio of 12 or more and an inhibition index of 1-12 is added. Under contact with distillate fraction at 260 to 357 [deg.] C., and the resulting product was contacted and hydrogenated with a hydrogenation catalyst consisting of a hydrogenated component consisting of a hydrogenated component to the non-acidic support at 260 to 357 [deg.] C. and 1480 to 1389 KPa, and -23 [deg.] C. A method for producing a naphthenic lubricating oil base, characterized by recovering lubricating oil having the following pour point. The method according to claim 1, wherein the telephone catalyst is composed of ZSM-5 and hydrogenated metal. The method of claim 2, wherein the ZSM-5 zeolite is partially in hydrogen form. The method of claim 2 wherein the ZSM-5 zeolite is combined with zinc. The method of claim 3 wherein the ZSM-5 zeolite is combined with zinc.