DE2821159A1 - PROCESS FOR RECOVERING SUBSTANTLY ASH-FREE LUBRICATING OIL - Google Patents

Description

This invention relates to the recovery of substantially ashless lubricating oil from used, lubricating oil containing ash-forming components.

This process is, in particular, the removal of impurities from the used Lubricating oil, such as around metal components and compounds of nitrogen, sulfur and oxygen as well as around the Removal of gasoline.

The oil purified by the method of the invention can be used as an oil base for the production of high quality lubricating oils.

In recent years, more and more additives such as detergents are used to reduce the Pour point, oxidation inhibitors, and viscosity index improvers in hydrocarbon-based lubricating oils used. While these additives have significantly improved the effectiveness of the lubricating oils, they have they cause considerable difficulties when recovering the used oils. To put it more specifically When lubricating oils are used, they collect resins, carbon, dirt, worn metals and others Impurities that remain suspended in the engine oil due to the new detergents. With these Detergents can be calcium and barium salts of alkylbenzenesulfonic acids and ashless detergents act like alkyl substituted succinic imides. These suspended impurities become the largest Part removed from the engine during the oil change and remains in the drained oil.

The economical removal of contaminants from used lubricating oils and those containing detergents Making reusable oils has become a difficult one

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Problem develops and these difficulties decrease with the provision of effective detergents more and more to.

The novel additives have also created another difficulty in that these too Additives must be removed from the base oil, thus the recovered oil for reformulation a highly effective lubricating oil is suitable.

This is used to separate carbon and dirt particles from lubricating oils that do not contain any or only relatively ineffective detergents contained, procedures used cannot be used to recondition used lubricating oils that contain effective detergents will. Since today almost all mineral lubricating oils have a large number of highly effective detergents and because they are collected in a common container when the lubricating oils are drained Today all used lubricating oils that are eligible for reconditioning or recovery come, highly effective detergents.

It is therefore an object of the invention to provide a method for the recovery of used lubricating oils available, whereby through this Process removes both the additives and the solid contaminants from the used lubricating oil should be.

This object is solved by the invention by a method for recovering substantially ashless lubricating oil from used, ash-forming components containing lubricating oil by

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a) Contacting the used lubricating oil with an aqueous solution of an ammonium salt, dispersing this salt in the oil and reacting this salt with the ash-forming components, and

b) separating the oil phase obtained, this process being characterized in that that the majority of water and light hydrocarbons from the obtained Mixture of used oil and solids is removed.

In practicing the invention, the recovered The oil phase is preferably separated off by filtration; it is optionally subjected to a hydrotreating treatment subjected and then the volatile components are driven off. It becomes a high quality one Obtain base oil for lubricating oil that is free of solids and additives. The mixture obtained from light hydrocarbons and water is cooled, turning them into a layer of light Separates hydrocarbons and a layer of water. The hydrocarbon layer can be pumped to the storage tanks and the water layer can can be reused in the system.

In a preferred embodiment of the invention, the water and light hydrocarbons are removed by distillation. Another preferred embodiment of the invention provides that the water and the light hydrocarbons are removed by short path distillation.

In another preferred embodiment of the invention, in an additional stage, the

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traded oil phase of hydrotreating treatment -subjected. For this purpose, the oil phase is in the presence of hydrogen and a hydrotreating catalyst subjected to such temperature, pressure and time conditions that a "hydrotreated" Base oil is created. The oil obtained in this way is then freed from light components in a stripping zone and a hydrotreated product suitable as a base for lubricating oils is then obtained as the process product oil.

The used lubricating oils used in the invention are primarily used oils from machines for internal combustion, such as oils from crankcases of, for example, gasoline engines or diesel engines. Other sources of used oils include steam turbine, transmission and gear oils, Steam engine oils, hydraulic oils and heat transfer oils a.

Refined paraffin-based, mixed-based or naphthenic crude oils are used for the above purposes. Their viscosities are generally in the range of about 20 to 400 Centistoie at 38 ⁰ O. These oils also contain various additives such as oxidation inhibitors (eg, barium, calcium and Zinkalkylthiophosphate and di-t-butyl-p-cresol), antiwear agent (e.g. organic lead compounds such as lead diorganophosphorodithionates and zinc dialkyldithiophosphates), rust inhibitors (e.g. calcium and sodium sulfonates), dispersants (e.g. calcium and barium sulfonates and phenoxides), viscosity index improvers (e.g. polyisobutylenes, poly (alkyl styrenes), detergents

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Alkylbenzenesulfonic acids) and ashless detergents such as alkyl-substituted succinic imides.

If desired, the water carried along in the untreated used oil can be added prior to the process according to the invention removed. Such a separation can be achieved by removing the water phase, e.g. in the Carry out storage containers for the used lubricating oil.

Examples of suitable ammonium salts which come into consideration as treatment agents in the invention, are ammonium sulfate, ammonium bisulfate, ammonium phosphate, Diammonium hydrogen phosphate, ammonium dihydrogen phosphate and mixtures of these salts.

If desired, the precursor of such an ammonium salt can also be used in place of some or all of the Ammonium salt can be used. Some examples of such precursors are ammonium thiosulfate, ammonium polyphosphates such as ammonium metaphosphate, urea sulfate, guanidine sulfate, urea phosphate and Guanidine phosphate. Other suitable precursors are reactive combinations of ammonia and / or Ammonium hydroxide with sulfuric acid and / or phosphoric acid and / or ammonium hydrogen sulfate or ammonium hydrogen phosphate, i.e. ammonium bisulfate, diammonium hydrogen phosphate and / or ammonium dihydrogen phosphate. When the precursor is a combination of such with each other Contains reactive components that give the desired salt "in situ", the Components of the combination can be introduced at the same time, or one of the components can be introduced before the Introducing the other components.

Although the concentration of the treatment agent in the aqueous solution is not essential to the invention and

more dilute solutions can also be used, the economic efficiency of the process is increased by using relatively concentrated solutions, so that the amount of water to be removed afterwards is not too large. In general, the concentration of the treating agent in the aqueous solution in the range of 30 to 95% by weight, typically about 80% by weight of that of a solution saturated with the treatment agent at 25 ° C. Often there is something Water is present in the used oil and in such cases the concentration of the treating agent can be adjusted accordingly.

In the method according to the invention, the treatment agent should be used in an amount at least sufficient to contain all metal components to react in the used oil. Although the weight ratio of the treating agent to that used oil depending on the nature and the concentration of metal-containing components in the oil and the particular treatment agent used can vary widely, it is generally in the range from 0.002: 1 to 0.05: 1, preferably in the range from 0.005: 1 to 0.015: 1 and typically at about 0.01: 1. Although larger amounts of the treating agent can be used, in most cases one will refrain from doing so as it would just be a waste.

Referring to Figure 1, used oil is extracted the storage tank 1 is fed to the heater 3 via the line 2. Aqueous treatment agent, diammonium hydrogen phosphate contains, is from the dressing tank 8 via the line 7 in a small excess compared to the amount that is required to react with the ash-forming components in the used oil,

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introduced into line 2. After passing through the heater 3, the obtained becomes hot Mixture of oil and treatment agent introduced via line 4 into a contact device 5, which is sufficiently agitated, e.g., by paddles 6, to ensure thorough dispersion of the aqueous treatment agent in the oil phase of the mixture which is fed into the device 5 is initiated to ensure. At present, it is preferred to have the aqueous treating agent above of the heater 3, since a relatively small volume of this agent is used. That However, aqueous treatment agents can also either be fed into line 4 after the heater 3 or directly are introduced into the touch device 5.

The mixture of used oil and aqueous treatment agent is in the touch device for a period of time and under temperature and pressure conditions that are sufficient to prevent the reaction between the treatment agent and im to bring about all of the ash-forming components present in the used oil.

After a sufficient reaction of the ash-forming components in the hot oil with the treatment agent is the reaction mixture obtained, which has a continuous oil phase, via line 9 in introduced the upper part of a distillation device 10. In one embodiment of the invention Before the emulsion enters the distillation device 10, a slurry of a filter aid is used in oil or in a light hydrocarbon, e.g. from phase 44, the system from the dressing tank added via line 12.

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Suitable tools in the method according to Invention are diatomaceous earth, perlite and cellulose fibers Diatomaceous earth is currently preferred.

In one embodiment of the invention, the the upper end of the distillation device 10 is maintained at a temperature and pressure which are sufficient are a short-path distillation (flash distillation) of the main part of the components water and light To effect hydrocarbons of the mixture. These components are then via the line 13 in a Phase separator 14 passed where a Hydrocarbon layer 15 and a water layer forms. The water layer can via the line 19 removed and discarded or it can optionally used for other purposes, e.g. to generate steam.

The remaining mixture obtained, which has a sulfated ash value of from about 0.3 to about 10% by weight according to ASTM D 847-72 without any filter aid or excess treating agent is a hot oil phase that is essentially free of water, but Excess treatment agent, some remaining water and any filter aid used in addition to the ash-forming solids originally present or arising therefrom in the used contains oil. It is led down through the distillation device.

Although not required, it is currently preferred to add steam to the distillation via line 4-0: device 10 to initiate while the oil is still at an elevated temperature in order to remove the

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to pump light components and the remaining water out of the system. Afterwards it becomes volatile Fractions freed and still hot oil passed through line 20 to a filter 21 to suspend and Separate any ash-forming materials that have been carried along.

As already stated, a filter aid can remove the emulsion from the volatile Ingredients are added to the later separation of the solids from the essentially to facilitate anhydrous oil phase. However, it is preferred that the filter 21 be equipped with one of the foregoing Filter aid is coated beforehand, this filter aid being applied directly to the filter will. If desired, the filter aid can be added to the emulsion prior to removing the volatile Components are added and used to coat the filter beforehand.

In a preferred embodiment of the invention, the filter cake is discharged from filter 21 via the line 4-7 is removed and, if necessary, fed to an oven, where the diatom Contains ash, is burned or calcined and is then discharged via the waste line 4-9 or im Circuit is passed to the dressing tank 11 for further use in the system.

The filtered oil is essentially free of ash-forming Components that were previously contained in it. Usually it has a sulfated ash value of about 0.01 to about 0.3 wt% according to ASTM D 84-7 ~ 72, without excess treatment agent and filter aid that has inadvertently passed through the filter could be. This recovered oil is

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suitable for a variety of industrial applications, such as heating oil, in lubricant formulations or in the manufacture of certain types of lubricating oil. If desired, the oil can be removed from the system via line 23.

In a preferred embodiment of the invention, however, the hot oil is supplied after filtration through the line 22 to the heater 25 to its temperature be increased to 200 to 480 ⁰ G. If desired, a first / portion of hydrogen is supplied via line 24. The hot oil obtained, with the hydrogen possibly contained, is then passed through the contact device 26, where the sulfonates contained in the oil decompose.

The touch device 26 preferably contains bauxite or a bed of adsorbing activated carbon, but other adsorbents can also be used in it, such as silica gel, clay, activated alumina, or mixtures thereof. The adsorbents cause first of all the decomposition of the ammonium salts of the sulfonic acids and the ash-free detergents in the oil. In addition, a small part of the resulting products accumulate on them, thereby preventing undesirable substances from entering Decomposition products in the hydrotreater is prevented. Such adsorbents can by usual measures can be regenerated and reused.

In a less preferred embodiment, the touch device 26 is omitted and the small amount of the ash-forming components and very polar materials present in the filtered low-ash oil is

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heating the oil to a temperature between 300 to 40O ⁰ C, for example about 380 ⁰ C, in the presence of hydrogen and an adsorbent suspended in the oil. After such a treatment, the oil is heated to a temperature in the range from 60 to 200 ^° C., for example about 150 ^° C., and filtered again. The adsorbents already mentioned for the touch device can be used and similar results are achieved.

The adsorbent preferably contains 0.2 to 20% by weight of at least one metal from groups VIA and VIII, based on the total weight of the modified adsorbent. This modified adsorbent. is preferred by impregnating the adsorbent with an aqueous solution of a water-soluble compound of a metal from the groups mentioned of the Periodic Table of the Elements and subsequent evaporation of the water manufactured. Currently water-soluble compounds preferred for this purpose are iron compounds, such as Ferric ammonium oxalate, ferric ammonium citrate, Iron (III) sulfate and iron (II) ammonium sulfate.

The treated oil is fed from the contact device 26 via the line 27 to the hydrotreater 28, which is kept at an elevated temperature and in which the various systems of additives that were contained in the original oil, can be destroyed. The hydrotreater is used for the desired Hydrotreating conversion of hydrogen via line 29, which is in communication with the line 27, initiated. The hydrogen can also be sent directly to the hydrotreater are fed. In the hydrotreater 28, the oil is subjected to hydrogenation conditions in the presence of a catalyst exposed, which has sufficient effectiveness,

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about the undesired compounds and the unsaturated ones Remove materials and decompose the remaining sulfur-containing, oxygen-containing and to bring about nitrogenous substances.

Suitable catalysts for use in hydrotrater 28 are the Group VIA and VIII metals and mixtures of which on a refractory support, commonly used in hydrodesulfurization processes.

After the hydrotreating treatment, the obtained oil becomes via line 30 of a separating reflux column 31 supplied to remove the water and other by-products from previous treatments of the Oil is used. If desired, and especially when HCl is present, water can be injected into column 31 to remove most of any HGl and some of H ^ S and NH * as water-soluble salts. The fraction leaving the top of column 31, which is hydrogen, H2S, NH, and water containing it is over the pipe fed to the unit 33 for the removal of sulfur. For example, this unit has a bed Zinc oxide, with the help of which ^ S is removed. The sulfur-free hydrogen stream obtained is thereafter passed via line 34- to cooler 35. Then it will be Ammonia removed e.g. by washing with water in a unit not shown. Via the line 36 is Hydrogen then returned to line 29.

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An example of another material that can be used in the unit 33 to good effect, is iron oxide. Alternatively, a solution process can be used in which alkanolamines and / or other amines are used, with H ^ S subsequently increasing Sulfur in a process of the Claus process is oxidized.

The residues from the column 3 "l are on the Line 37 of the distillation device 38 (lubestock stripper), where a further steam treatment takes place, via the line 39 is fed.

The driving off of the volatile constituents of the oil, preferably by steam, is an essential one Feature of a preferred embodiment of the invention, since it allows the light hydrocarbons, which boil lower than the oil, such as kerosene or heavy benzine, are removed. Such light hydrocarbon products may or may not be present in the used oil also occur as by-products of the hydrogenation treatment. Alternatively, this can also be removed volatile components with gases such as hydrogen.

The warm product obtained, which has been freed of volatile constituents and which essentially consists of a pure base oil for lubricating oils, is after cooling, for example in a heat exchanger as at 25, via line 41 to a storage tank (not shown) for storage and can then be free of additives Base oil can be used to reformulate a lubricating oil with additives. 809851/0645

The distillate from the top of device 38, which consists essentially of fuel oil and water, is via the line 42 to the settling device 43 passed, where a hydrocarbon phase 44 and a water layer 45 is formed. The hydrocarbon layer 44 is removed via line 46 and if necessary combined with the hydrocarbon phase in the storage tank 18 for further use. The minor one Amount of the gases contained in line 46 can be burned.

More detailed information on the process conditions is given below, with reference in the first column the units in FIG. 1 are taken.

Pig. 1 No. unit ■ Preferred areas 160 ^u C 160 ⁰ C 60-200 ⁰ C. symbol Heater typical 160 ⁰ C atm. atm. 1-17 atm. 3 temperature atm. Time 30 min. Treatment Pressure 14.6 Weight 115 ⁰ C 7th middle ratio medium: head atm. 0.005: 1-0.05: 1 Oil 0.01: 1 Temperate. Touch Pressure 1.1 60-20O ⁰ C 5 Furnishing temperature floor 1-17 atm. Pressure 14.6 Temperate. 10 min -2 h. Pressure 1.1 Destilla 10 tion 60-200 ⁰ C. 0.14-1.4 atm. 60-200 ⁰ C. 0.14-1.4 atm.

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Fig. 1
symbol No. unit typical Preferred areas 14th Phase separator Temperature 40 ⁰ C 0-80 ⁰ C Pressure 1 atm. 1-3.1 atm. 21st filter Temperature 115 ⁰ C 60-200 ⁰ C. Pressure difference Plate and
Frame filter
5.4 atm. 0.3-6.80 atm. continuous
Rotation
filter 0.7 atm. 0.14-0.95 atm. 48 oven Temperature 760 ⁰ G . 650-870 ⁰ C. Pressure 1 atm. about 1 atm. 12th Filter-
HiIfsm. Weight ratio Medium: oil 0.01: 1 0: 1-0.15: 1 24 H ₂ supply 111 vol./vol. oil 80-3000 vol / vol
oil 25th Heater Temperature 37O ⁰ C 200-480 ⁰ C. Pressure 50 atm. 10.2-204.1 atm. 26th Touch-on
right Temperature 37O ° C 200-480 ⁰ C. Pressure 50 atm. 10.2-204.1 atm. 28 Hydrotreater Temperature 360 ⁰ C 200-430 ⁰ C. Pressure 49.7 atm. 10.2-204.1 atm. 29 H ₂ supply 222 vol./vol. oil 80-3000 vol / vol.
oil 31 Reflux Temperature 325 ° C 290-400 ⁰ G Pressure 48 atm. 40.8-54.4 atm. 33 Sulfur-
distance Temperature 290 ° C 150-430 ⁰ C. 809 Pressure 47.6 atm.
8S1 / 064S 6.80-204.1 atm.
- 18th

Mg. 1 No. unit typical Preferred areas symbol cooler Inlet temperature 35 29O ⁰ G 260-370 ° C Outlet temperature 55 ⁰ G 40-95 ° G Destilla 38 tion Temperature 37O ⁰ G 28O- 395 ° G Pressure 1.4 atm. 1-3.4 atm. Weaners Temperature 55 ° C 0-80 ⁰ G 43 Pressure 1.1 atm. 1-3.1 atm.

Typical compositions of matter for the main streams are given in Table I below specified under the operating conditions specified in the overview above.

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2_ 7th 0.45 Tabel 22 24 2 150 67 I. Electricity day 34 37 42 46 6644 9 kg units 6645 4th 66 Per 30 32 32 6293 32 32 Stream no. 51 6644 20th 29 6325 32 oil 15th 6644 13th <1 Metals plus P * 50 13th 44 <1 <1 S * 10 45 13th 10 <1 <0.1 0 ** 417 140 10 45 <0.1 61 320 N * 557 10 .54 54 20th H ₂ O 2 20 20 NH ₅ 4th 14 14 H ₂ S 300 185 90 90 90 light hydrocarbons 70 300 275 185 fabrics 150 132 5 5 5 (NH ^) ₂ HPO ₄ 137 132 114 1 1 1 CH ₄ 67 115 114 ^H 2 128 67 insoluble in oil 128 Diatom .enerde 70

41 6261

* Present in combined form in the used oil yj

** Available in combined form in the used oil, excluding HoO.

In another embodiment of the invention, used oil from the storage tank 101 is over the line 102 is fed to the heater 103 and then to the touch device 106. The watery one Treatment agent containing diammonium hydrogen phosphate is supplied from the dressing tank 105 to the line 104- led. Optionally, treatment agent precursors such as ammonia, phosphoric acid and Water can be introduced into the heated oil after the heater 103, with the treatment agent forms "in situ" in the line 102 and in the touch device 106. The oil is from the heater 103 in a mixture with the treatment agent in the touch device equipped with a stirrer where the mixture is kept stirring for a time sufficient to keep up with the ash-forming Components of the oil react. A recycle stream through line 152 to the pump is preferred 153 and then passed through the heater 154 · before it is returned to the touch device 106 causing its contents to be heated and agitated. Other stirring devices can also be used will.

Thereafter, the mixture is fed via line 107 to a second contact device 109, which is maintained at a temperature in the range from about 110 to about 14-0 ⁰ C for a period of time sufficient to allow distillation of a major part of the water and at least part of the to effect the presence of light hydrocarbons. As a result, while staying in the touch device 109 is substantially all of the water and at least

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removed a portion of the light hydrocarbon components of the mixture via line 110 and goes to the separator 111, where there is a hydrocarbon layer and a water layer forms. The hydrocarbon layer can then be conducted into the storage container 113 via the line 112 will. The water layer can be removed and discarded or used for other purposes. A recycle stream via line 155 to pump 158 and then through heater 108 is preferred guided before it is introduced into the touch device 109, causing heating and movement of the contents of this reactor takes place. Other stirring devices can also be used in this pail be used.

The remaining mixture obtained contains the oil phase and is essentially free of water. It is sent via line 114 to a third touch device 116 supplied where it is mixed with diatomaceous earth which is preferred in the device 116 as a slurry in light hydrocarbons via line 118 from the dressing tank 119 is introduced. As the light hydrocarbons, there can be used those which are involved in this integrated processes can be obtained. A recycle stream through line 157 is preferred Pump 158 and then passed through heater 115 before being initiated into touch device 116 the contents of this device being heated and agitated by the circulating flow. About still existing amounts of water and light hydrocarbons are transferred from the device 116 line 159 removed.

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Palls desired any or two or all of the touch devices 106, 109 and 116 will have Coats provided in order to heat them by steam or by another heat source, so that the contents of the touch devices can be maintained at the desired temperatures. Everyone or two or all of the devices 106, 109 and can be equipped with stirrers. At a currently less preferred embodiment of the invention is a stirrer in place of the circulatory system any one or more of the touch devices used, with additional heating by heating in the line in front of the touch device and / or by heating jackets of the touch devices. In addition, the procedure can also be used upon request performed without the touch device 116, in which case the diatomaceous earth is introduced into line 114 through line 118, from where the obtained mixture of oil, solid impurities and Diatonu_eenerde fed directly to the filter 121 will. Any or two or all of lines 102, 107 and 114 can also be included in the recycle streams, if desired for touch devices 106, 109 and, i.e., lines 152, 155 and 157, instead of inserting them directly into the corresponding touch device, as in FIG. 2.

After the diatomaceous earth has been added, the hot mixture obtained is fed via line 117 to a filter 121 which, if necessary, can be coated beforehand with diatomaceous earth. In this case, too, other filter aids such as perlite or cellulose fibers can be used.

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The filter cake from filter 121 is removed via line 147 and is optionally passed through the furnace 148. After burning or calcining is at least a part of the ash obtained, which contains the diatomaceous earth, fed to the waste via line 14-9 or via lines 120 and 160 to the dressing tank 119 for further use in the system. Fresh diatoire earth is made over the Line 160 brought up. Light hydrocarbons are used, which are deposited in the integrated process and which are via the Line I51 are brought up.

When this embodiment of the invention is carried out, an advantageous increase in the rate of filtration of the oil through the filter 121 is achieved if the mixture of oil and the treatment agent is kept for a period of at least 10 minutes at a temperature of 60 to 120 ^° C. before further treatment will.

The hot-filtered oil is essentially free of ash-forming ingredients that were previously contained in it and is suitable for a variety of industrial uses. This treated oil can be removed from the system via line 123 will.

In the preferred integrated process according to the invention, however, after the filtration, the hot oil is fed to the heater 125 via the line 122 in order to raise its temperature to 200 to 480 ^° C. for another

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Increase treatment in a manner similar to that in Figure 1. If desired, a first part can be made Hydrogen can be supplied via line 124. The hot hydrogen-containing oil is then through the touch device 126 led, where a decomposition of the sulfonates contained in the oil entry.

It is presently preferred that the touch device 126 have bauxite or a bed of adsorbent Contains activated carbon. However, other adsorbents can also be used in this unit, such as Silica gel, clay, activated alumina, and mixtures thereof. The adsorbents serve to decompose the ammonium salts of sulfonic acids and the ash-free detergents contained in the oil are. The adsorbents also hold back a small proportion of the products obtained and prevent them thereby the continuation of such undesired decomposition products to the hydrotreater. Such adsorbents can be regenerated and reused in the usual way.

Less preferred, it is to omit the touch device 126, the small amount of ash-forming components and highly polar materials in the filtered oil with a low ash content by heating the oil to a temperature in the range of about 300-410 ⁰ C, for example about 380 ° C to remove in the presence of hydrogen and an adsorbent suspended in the oil. After such treatment, the oil is heated to a temperature in the range of 60-200 ⁰ C, for example, about 150 ⁰ C cooled and filtered again. It can

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In this case, too, the adsorbents already mentioned can be used and similar results are obtained achieved.

The adsorbent preferably contains about 0.2 to about 20% by weight of at least one of the metals from the groups VIA and VIII of the Periodic Table of the Elements, these percentages by weight based on the total weight of the modified adsorbent are related. This modified adsorbent can be impregnated with the adsorbent an aqueous solution of a water-soluble compound of one of the metals mentioned and subsequent evaporation of the water. The currently preferred compounds are iron compounds in this case too such as ferric ammonium oxalate, ferric ammonium citrate, Iron (II) sulfate and iron (II) ammonium sulfate.

The treated oil obtained is then out of touch device 126 is fed via line 127 to the hydrotreater 128, which at an increased Temperature is maintained so that the various systems of additives added to the source oil have been destroyed. For hydrotreating treatment the hydrogen is added to the system via line 129 in communication with line 127 or if desired fed directly to the hydrotreater 128.

In the hydrotreater 128, the oil is treated under hydrogenation conditions in the presence of a catalyst until the undesired compounds and unsaturated materials are removed and the residues of sulfur-containing, oxygen-containing and nitrogen-containing compounds are decomposed, so that an oil-

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defaced product that is suitable for further cleaning for a base oil for lubricating oil.

Suitable catalysts for treatment in Hydrotreater 128 are those made from metals of the groups VIA and VIII and combinations thereof on a refractory support as used in conventional hydrodesulfurization processes be used.

After the hydrotreating treatment, the obtained oil becomes via line 130 to a separating reflux column

131 led where water and various other by-products from previous treatments of the oil. If desired and especially if HCl is present, water can be injected into column 13I to remove most of any HGl and part of H ^ S and NH, to facilitate as water-soluble salts. On the head the column 131 is a stream of hydrogen, Contains HqS, NH, and water and the overflow

132 is fed to the sulfur removal unit 133. This unit, which can contain a bed of zinc oxide, for example, removes H ₂ S. The sulfur-free hydrogen stream is then passed to cooler 135 via line 134-. Ammonia is then removed, for example by washing with water in a unit (not shown) in line 136. Hydrogen is then fed back to line 129 via line 136.

Another example of a suitable material in unit 133 is iron oxide. Alternatively, a Solvent processes can be used in which alkanolamines and / or other amines are used

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and HoS afterwards to sulfur in a Claus process is oxidized.

The bottom product from column 131 is fed via line 137 to a distillation device 138, where a further steam treatment is carried out by introducing steam via line 139.

The driving off of the volatile constituents of the oil, in particular driving off with water vapor, is essential to the integrated process of the invention as it serves to remove those light hydrocarbons to remove that boil lower than the oil, such as kerosene or heavy fuel. These Hydrocarbons are present in the used oil or arise as by-products in the hydrogenation. Alternatively, an abortion can also occur volatile constituents with gases such as hydrogen.

The product obtained, freed from volatile components, consists essentially of pure base oil for lubricating oils. After cooling, for example in a heat exchanger 125, it becomes closed via line 141 a storage container, not shown, and can subsequently be used as a base oil free of additives for the reformulation be used with additives.

The top outlet of the distillation device 138, the consists essentially of heating oil and water, via line 142 to a settling device 143

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where a hydrocarbon phase 144 and form a water layer 145. The hydrocarbon layer 144 is via line 146 and, if desired, with the hydrocarbon phase combined in the storage tank 113 for further use or in the circuit to the serving tank 119 via the line 151 led. The small one in line 146 Amount of gas can be removed by burning.

Below is a summary of the typical and preferred reaction conditions in given to the various units of the system according to FIG.

Fig. 2 No. unit Typical Preferred Areas 60-120 ⁰ C. symbol Heater Temperature 95 ° C ' 1-17 atm. 103 Pressure 1.2 atm. Treatment 104 middle Weight ratio Medium: oil 0.005: 1-0.05: 1 0.01: 1 Contact 60-120 ⁰ C. 106 Facility Temperature 95 ° C 1-3.4 atm. Pressure 1.2 atm. 10 min -2h Time: 30 minutes Touch 110-140 ° C 109 Facility Temperature 125 ⁰ C 0.3-1.7 atm. Pressure 1.1 atm. 10 min -2h Time: 30 minutes

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Fig. 2

Icon no. Unit

typical

128 hydrotreater temperature 360 C

Pressure 49.7 atm.

Preferred area

116 Touch Temperature 160 ⁰ O 140-200 ⁰ C. Facility Pressure 1.1 atm. 0.3-1.7 atm. Time: 30 minutes 10 min -2h 111 Phase Temperature 40 ⁰ O 0-80 ⁰ C separator Pressure 1 atm. 1-3.1 atm. Temperature 115 ° 0 60-200 ⁰ C. 121 filter Pressure difference Plate and
Frame filter
5.4 atm. 0.3-6.80 atm. continuous
Rotation
filter 0.7 atm. 0.14-0.95 atm. Temperature 760 ⁰ C 650-870 ⁰ C. 148 oven Pressure 1 atm. about 1 atm. Weight ratio 118 FiIter-
HiIfsm. Medium: oil 0.01: 1 0: 1-0.15: 1 111 vol./vol. oil 80-3000 vol / vol
oil 124 H ₂ supply Temperature 37O ⁰ C 200-480 ⁰ C. 125 Heater Pressure 50 atm. 10.2-204.1 atm. 126 Touch-on Temperature 37O ⁰ C 200-480 ⁰ C. direction Pressure 50 atm. 10.2-204.1 atm.

200-430 ⁰ C 10.2-204.1 atm.

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Fig. 2 unit typical Preferred area Symbol no. H ₂ supply 222 vol./vol. oil 80-3000 Vol./Vo
oil 129 Reflux Temperature 325 ° C 290-400 ⁰ C 131 Pressure 48 atm. 40.8-54 , 4 atm. Sulfur- 133 distance Temperature 290 ⁰ C 150-430 ⁰ C

Pressure 47.6 atm.

Cooler inlet temperature

290 ⁰ G

Outlet temperature 55 ⁰ C

Distillation temperature 37O ⁰ C

Pressure 1.4 atm.

Settling temperature 55 ⁰ C

Pressure 1.1 atm.

6.80-204.1 atm.

260-370 ⁰ C.

40-95 ° C

280-395 ⁰ C 1-3.4 atm.

0-80 ⁰ C
1-3.1 atm.

Typical compositions of matter are given in Table II below for the main streams among the. mentioned in the above overview Operating conditions specified.

- 31 -

809851/0846

Table II
0.45 kg units per electricity day

Stream no. 102 104 107 117 122.124 12 ^ 130 1j> 2 r $ ± 1_37 142 146 VQ

oil 6644 6644 6644 6645 6325 32 32 6293 32 32 6261

co metals plus P * 51

S S * 15

£ ο ** 50

- ^ N * 10

σ H ₉ O 417 140 557 2 2 54 54 61 320 f

Ξ «,

^OT H ₂ S.

light hydrocarbons 300 300 150 150 275 185 185 90 90 90

70

13th 13th 13th 2 2 <1 54 61 45 45 44 4th 4 ' <1 20th 20th 10 10 10 <0.1 14th 557 54 20th 14th

CH ₄

H ₂

insoluble in oil 128

Diatom eenerde

67 67 137 132 132 5 5 5 NJ 66 67 115 114 114 1 1 1 OO 128 NJ 70

* Present in a combined form in the used oil _{(J =)}

** Available in combined form in the used oil, excluding H _P 0.

Short-path distillation (flash distillation) is understood here to mean a distillation in which the entire or substantially all of the heat used in the distillation process to convert the liquid is used in steam, supplied as sensible heat to the mixture containing the liquid where the mixture is under a certain pressure and the evaporation of the liquid afterwards occurs with lowering of the pressure. The "short path distillation" is consequently in the Process according to Fig. 1 used to remove water and light hydrocarbons from the mixture, which leaves the touch device 5. The term "distillation" is used here that it denotes the process in which at least the majority of the heat required for conversion of liquid in vapor is supplied to the mixture containing the liquid, the Mixture is essentially at the pressure at which evaporation occurs. As a result, will the "distillation" in the process of Fig. 2 to remove water and light hydrocarbons from the mixes of touch devices 109 and 116 used.

809851/0646

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Claims (1)

Dr. Michael Hann
Patent attorney
Ludwigstrasse 67 6300 Giessen (1142) H / Fe Phillips Petroleum Company, Bartlesville, OkIa., USA VEEB ¹ AHREN "TO RECOVER YON IN ESSENTIAL ASH SHEY OIL Priority: May 16, 1977 / USA / Ser.No. 797 212 October 3, 1977 / USA / Ser.No. 838 773 Patent claims: (1 Λ Process for the recovery of substantially ash-free lubricating oil from used lubricating oil containing ash-forming components a) Touching the used lubricating oil with a
aqueous solution of an ammonium salt, dispersing this salt in the oil and reacting
this salt with the ash-forming components and b) separating the oil phase obtained, characterized,
that most of the water and light hydrocarbons are removed from the resulting mixture of used oil and solids. 809851/064 «~ ² " ORlGlNAL INSPECTED 2. The method according to claim 1, characterized in that the water and the light hydrocarbons can be removed by distillation. 3. The method according to claim 2, characterized in that substantially all of the water and the all hydrocarbons are removed by a short path distillation. 4-, method according to claim 1 or 3, characterized in that the treated oil by filtration from the Preserved mixture of used oil and pesticides is separated. 5. The method according to claim 4-, characterized in that the separated oil is subjected to a hydrotreating treatment is subjected. 6. The method according to claim 5,
characterized in that the hydrotreating treatment effluent containing sulfur and hydrogen is contacted with zinc oxide or iron oxide to remove sulfur. 7 method according to claim 3, characterized in that the water and the light hydrocarbons of the mixture of the short path distillation at a temperature in the range from 60 to 200 ° C and a pressure in the range from 0.4 to 1.4 atm. be subjected. 809851/0646