DE1645791B2 - Process for the two-stage hydrogenation refining of crude petroleum fractions - Google Patents

Description

The invention relates to a method of making white oils, and in particular relates to a two-stage, catalytic hydrogenation process for the production of white oils in high yield, the meet special purity criteria.

Common refining processes involve treating crude lubricating oil fractions of suitable viscosity with large amounts of sulfuric acid and subsequent neutralization and washing with water. Are disadvantageous the relatively low yields of the desired products, as well as problems with the removal of the acidic parts. Furthermore, such a treatment of highly viscous fractions is difficult because emulsions or Deposits occur.

From US-PS 27 79 713 there is also a process for the production of water-clear oils by two-stage hydrogenation known from crude lubricating oil fractions, the lubricating oils thus obtainable are neither technical purely nor are they suitable for food use

The invention relates to a process for two-stage refining of crude petroleum fractions, reacting a Rohschmierölfraktion with hydrogen in the presence of hydrogenation of a sulfur resistant hydrogenation catalyst at a temperature of 315 to 400 ⁰ C and a pressure of 105-350 atm in and the oil subsequently hydrogenated with hydrogen in the presence of a catalyst comprising a platinum group metal and alumina at a temperature of 232-371 ⁰ C which is at least about 28 ° C below the temperature of the first hydrogenation, and a pressure from 70 to 350 atmospheres gauge further refined, which is characterized in that to produce a white oil with technical purity and with a UV absorption per cm of optical path length of a maximum of 4.0 at 280 to 289 πιμ, 3.3 at 290 to 299 mu, 2.3 at 300 to 329 ΐημ and 0 , 8 at 330 to 350 πιμ a crude lubricating oil fraction with a specific dispersion of less than 180, which has been obtained by distilling a crude oil i st, used the first hydrogenation at an hourly space velocity of 0.1 to 0.5 g / g / h and an amount of hydrogen of 178 to 890 m ³ / m ³ and the second hydrogenation at an hourly space velocity of 0.15 to 0 , 75 G / G / h and an amount of hydrogen from 89 to 890 m ³ / m ³

The hourly space velocity is calculated from the weight of the feed that is passed over the unit weight of catalyst every hour. The amount of hydrogen is the amount of hydrogen used in m ³ per m ^{3 of} feed.

Apart from the fact that the process according to the invention can also process highly viscous charges and there are no undesirable waste products, it has the advantage over US Pat. No. 2,779,713 that it delivers white oils of particular purity in high yield. These are white oils whose UV absorption per cm of optical path length at 280-289 Γημ maximum 4.0, at 290-299 ηιμ maximum 3.3, at 300-329 ΐημ a maximum of 2.3 and at 330-350 πιμ is a maximum of 0.8 (see Code of Federal Regulations, Volume 21, Section 1212589).

The starting material will be a heavy or light one Crude distillate oil with a specific dispersion below 180 is used, the z. B. by distillation of a Naphthenic based light crude oils (e.g. Gulf Coast and California crude oils), from gasoline and kerosene The feeds used may have a viscosity Have between 50 and 7500 SUS at 38 ° C. If the oils contain paraffin, they are expedient before the first hydrogenation dewaxed, although dewaxing also follows the first hydrogenation can be carried out. The dewaxing takes place

according to usual methods. The hydrorefining in the first stage of the method according to the invention takes place at temperatures of 315-400 ⁰ C, of 105 to 350 atmospheres gauge pressures, space velocities of 0.1-0.5 w / w / hour and a quantity of hydrogen of 178-890 m ³ / m ³ . If the hydrorefining is carried out to prepare an oil technical grade, so are preferred working conditions temperatures of 315-370 ⁰ C, pressures of 105-210 atm, hourly space velocities of 0.2-0.5 w / w / hr and an amount of hydrogen from 178-534 m ³ / m ³ . In contrast, preferred conditions for the production of an oil for food use are temperatures of 343-385 ° C., pressures of 154-350 atmospheres, room flow rates of 0.15-035 G / G / h and hydrogen quantities of 267-890 m ³ / m ³ .

The hydrogenated oil from the first hydro refining is then subjected to less severe hydrogenation conditions in the second refining. The temperatures are 232 ° C (z. B. 260 ⁰ C) to 37 C and Γ are at least 28 ° C, preferably at least 42 ° C lower than those of first refining. The pressures are between 70-350 atmospheres, the room flow velocities between 0.15 (e.g. 0.25) and 0.75 G / G / h and the amount of hydrogen between 89 and 890 m ³ / m ³ .

The preferred conditions for the preparation of an oil technical grade are in the 2nd stage: atm temperatures of 274-343 ⁰ C, pressures of 70-210, space velocities of 0.25-0.5 w / w / hr and hydrogen amounts of 89 -534m ³ / m ³ . Are oils are prepared for food purposes, so the preferred temperatures are between 232 ° C (eg 260 ° C) and 330 ⁰ C, the preferred pressures from 140 to 350 atm, for the preferred hourly space velocities between 0.15 (., 0 , 25) and 0.35 G / G / h and the amount of hydrogen between 267 and 890 m ³ / m ³ .

Any sulfur-resistant base metal hydrogenation catalyst can be used as the catalyst in the first hydrogenation stage some of which are commonly used in the hydrogenation of heavy petroleum oils be used. Suitable catalytic components are, for. B. tin, vanadium, metals of group VIa des Periodic table, i.e. chromium, molybdenum and tungsten and metals of the iron group, i.e. iron, cobalt and Nickel. These metals are in a catalytically effective amount, e.g. B. 2-30 wt .-% present and can as Oxides or sulfides are present. Mixtures of the oxides or sulfides of the iron group with the oxides or Group VIa sulfides are very satisfactory catalysts.

Also compounds such as nickel molybdate, tungstate or chromate or thiomolybdate, thiotungstate or -thiochromate come into question, z. B. Mixtures of nickel or cobalt oxides with molybdenum, tungsten or Chromium oxides.

Usually these catalytic components are supported on solid and refractory oxide types, z. B. a predominantly calcined or activated bo Clay, used. Usual catalysts contain 1-10% of an iron group metal and 5-25% of the iron group Group VIa metal (calculated as oxide). The catalyst is advantageously cobalt molybdate or Nickel molybdate on alumina as a carrier. Such preferred catalysts can according to the method of US Pat. No. 2,938,002.

The catalyst for the second hydrogenation stage consists of a platinum group metal on alumina. It differs from the catalysts of the first hydrogenation stage in that it is normally not Resistant to sulfur. It includes catalytically effective amounts of platinum group metals, e.g. B. platinum, Palladium, rhodium or iridium, usually between 0.01 and 2 wt .-%, preferably between 0.1 and 1 wt%. The platinum group metal can be in metallic form or as an oxide. Is the If the catalyst is present in metallic form, it is expediently so finely divided that it can be determined by X-ray analysis is not detectable, d. that is, it is in the form of crystallites less than about 50 Å in size Von Platinum is preferred among metals of the platinum group. Optionally, those for the first and second Hydrogenation applied catalysts prior to their use, for. B. by heating in the presence of Hydrogen flushed with hydrogen at temperatures of 150-315 ° C or at temperatures of 315-427 ° C in the presence of hydrogen.

The alumina carrier is generally at least 75% by weight, preferably 85-99.8% by weight, based on the catalyst. The alumina catalyst support can be activated or y-alumina, alumina monohydrate, Alumina trihydrate or mixtures thereof. A suitably used catalyst support consists from a mixture of a major part, e.g. B. 65-95% by weight of one or more toy detrihydrates, Bayerite I, norstrandite or gibbsonite, and 5-35% by weight of clay monohydrate (boehmite), amorphous, hydrous clay or mixtures thereof. The alumina carrier can also contain small amounts of others solid oxides such as silica, magnesia, natural or activated clays (such as kaolinite, montmorillonite or Halloysite) titanium earth, zircon earth or their mixtures.

After the hydrogenation processes according to the invention, the hydrogenated oils can optionally be distilled or stripped to remove more volatile products that have formed. This distance increases the Flash point of the oil.

Technically pure white oil can be used for many purposes, e.g. B. in the manufacture of objects that come into contact with food, as an antifoam agent for coatings and in the manufacture of textiles and textile fibers.

Food grade white oils are widely used in processes related to food production related, for example, as defoamers, release agents, protective coatings and in Binder formulations. They are still used as a floating agent on fermentation fluids in the Used in making wines and vinegars.

The raw feeds used in the examples had a specific dispersion between 140 and 150.

example 1

Treatment of a raw lubricant fraction with
low viscosity

The starting material was a light crude lubricating oil distillate from the vacuum distillation of a light Gulf Coast naphthenic based crude having a viscosity of 54.5 SUS at 38 ° C and a Saybolt color from L-16. This oil was at 168 atü, 343 ° C, a hourly space velocity of 0.25

G / G / h and an ^{amount of hydrogen of 267 m 3} per m ^{3 of} feed in the presence of a catalyst of cobalt molybdate hydrogenated on alumina with 2.7% CoO and 11.9% MOO3.

This hydrogenated product was then subjected to a second hydrogenation at a pressure of 175 atmospheres, a temperature of 288 ° C., an hourly space flow rate of 0.25 g / g / h and an amount of hydrogen of 445 m ³ per m ^{3 of} coating in the presence of a catalyst Subjected to platinum on alumina with 0.6% platinum. This product was then steam distilled to give a white oil of technical purity in a yield of 94%. The properties of the product obtained are compared in Table 1 with those of the feed and the specifications for technically pure white oils. As can be seen from Table 1, the products obtained according to the invention meet the corresponding prescribed requirements.

Table 2 Table 1

Loading Received before kung product font*) Viscosity at 38 ° C 54.5 50.3 (SUS) Saybolt color L-16 > 30 S 20 min Distillation area 263-347 266-350 5-95% ( ⁰ C) UV absorption per cm optical path length at 280-289 πιμ - 0.121 <4.0 290-299 ηιμ - 0.079 S 3.3 300-329 ηιμ - 0.053 S 2.3 330-350 mu - 0.017 S 0.8

*) According to the Code of Federal Regulations, Volume 21, Section 1212 589 (USA).

Example 2

Treatment of a highly viscous
Crude lubricating oil fraction

The starting material was a heavy crude lubricating oil distillate from a vacuum distillation of a light Gulf Coast naphthenic based crude having a viscosity of 7280 SUS at 38 ° C and a Saybolt color of L-16. This oil was at 168 atmospheres, 371 ° C., an hourly room flow rate of 0.25 g / g / h and an ^{amount of hydrogen of 534 m 3 of} hydrogen per m ^{3 of} oil in the presence of a catalyst composed of cobalt molybdate on alumina containing 2.7% CoO and contained 11.9% MoO ₃ , hydrogenated.

This hydrogenated oil was then subjected to a second hydrogenation at a pressure of 168 atmospheres, a temperature of 288 ° C., an hourly space flow rate of 0.25 g / g / h and an amount of hydrogen of 445 m ³ per m ^{3 of} feed in the presence of a platinum on-alumina catalyst with 0.6% platinum. The product obtained was then distilled with steam and gave a white oil with technical purity in a yield of 94% f see Tab. 2).

Beschik- Received advance product font *)

Viscosity at 38 ° C
(SUS)

Saybolt color
Distillation area
5-95% ( ⁰ C)

UV absorption per cm
optical path length at

280-289 πιμ

290-299 πιμ
300-329 πιμ

330-350 πιμ

7280

L-16
454-538

2053 -

> 30> 20

395-504 -

0.239 0.203 0.200 0.089

ä 4.0 S 3.3 S 23 S 0.8

*) According to the Code of Federal Regulations, Volume 21, Section 1212 589 (USA).

Example 3

This example shows the production of a white oil for food use.

A light crude lubricating oil charge obtained by distilling a naphthenic based crude oil was treated as follows.

30th First stage Second
step catalyst Nickel molybdate
on clay Platinum on
Clay ³⁵ pressure (hydrogen partial pressure)
atü 175 175 Temperature ( ⁰ C) 363 249 Room flow velocity 0.23 0.23

speed per hour (G / G / h)

Amount of hydrogen m ³ 356

per m ^{3 of} feed

427

The overall yield based on the feed was 91%.

Table 3 shows the values obtained and the corresponding regulations.

Table 3 Loading Received before 50 kung product font*) 0.91 0.875 53.1 45.4 - density 55 Viscosity at 38 ° C 133.5 98.9 - (SUS) fails consists consists Specific dispersion Charring fails consists consists Substances **) 60 Sulfur compound - 0.048 <0.104 fertilize**) Maximum UV-Ab sorption in 65 260-350 iT ^ range

* \ Code of Federal Regulations, Vol. 21, Section 2 111 146. **) Determined in accordance with the analytical regulations of the US Pharmacopoeia, Revision XVI.

8th

The following catalysts were used:

Nickel molybdate Platinum on on clay Clay Ni (wt%) 2.92 _ Pt (wt%) - 0.574 M003 (wt%) 16.3 - S1O2 (wt%) 0.325 0.002 (Diameter mm) 1.6 1.6

Claims (3)

Patent claims: 1. Process for the two-stage refining of crude petroleum fractions, in which a crude lubricating oil fraction is hydrogenated with hydrogen in the presence of a sulfur-resistant hydrogenation catalyst at a temperature of 315 to 400 ⁰ C and a pressure of 105 to 350 atu and the hydrogenated oil is then hydrogenated with hydrogen in The presence of a catalyst composed of a platinum group metal and alumina further refined at a temperature of 232 to 371 ° C, which is at least about 28 ° C below the temperature of the first hydrogenation stage, and a pressure of 70 to 350 atmospheres, characterized in that for the production of a white oil with technical purity and with a UV absorption per cm of optical path length of a maximum of 4.0 at 280 to 289 μm, 33 at 290 to 299 πιμ, 23 at 300 to 329 ιτιμ and 0.8 at 330 at 350 πιμ a crude lubricating oil fraction with a specific dispersion of less than 180 obtained by distilling a crude oil is used, the first hydrogenation b With an hourly space flow rate of 0.1 to 0.5 G / G / h and an amount of hydrogen from 178 to 890 m ³ / m ³ and the second hydrogenation at an hourly space flow rate of 0.15 to 0.75 G / G / h and an amount of hydrogen from 89 to 890 mW ³ carries out jo 2. The method according to claim 1, characterized in that the first hydrogenation at a temperature of 315-370 ⁰ C, a pressure of 105-210 atü, an hourly space flow rate of 0.2-0.5 G / G / H and one Ji amount of hydrogen of 178-534m ³ / m ³ and the second hydrogenation at a temperature of 274-343 ° C, which, however, is at least 42 ° C below that of the first hydrogenation, a pressure of 70-210 atmospheres, an hourly room flow w speed of 0.25-0.5 G / G / h and a hydrogen amount of 89-534 mVm ^{3 is} carried out. 3. The method according to claim 1, characterized in that the first hydrogenation at a temperature of 343-385 ° C, a pressure of 154-350 atm, an hourly space velocity of 0.15-0.35 G / G / h and an amount of hydrogen of 267-890 m ³ / m ³ and the second hydrogenation at a temperature of 232-330 ⁰ C, which is however, at least 42 ⁰ C lower than that of the first hydrogenation pressure of 140-350 atm a, an hourly space velocity of 0.15 to 035 w / w / hr and a hydrogen amount of 267 to 890 m ³ / m ^{3 is} carried out.