JPH0152438B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to lubricating oil compositions with improved photostability. Recently, many methods have been proposed for producing lubricating oil by so-called high-pressure hydrorefining instead of the solvent extraction method. These lubricating oil distillates are produced by distilling the hydrotreated oil obtained by contacting lubricating oil fraction raw materials such as heavy hydrocarbon oils with hydrogen in the presence of a hydrotreating catalyst under high temperature and high pressure reaction conditions. This is to collect the amount. By such hydrorefining, a high quality lubricating oil with improved properties such as hue and viscosity index can be obtained. However, on the other hand, this type of hydrorefining also simultaneously converts some aromatic hydrocarbons into partially hydrogenated aromatic hydrocarbons, and due to the presence of this partially hydrogenated aromatic hydrocarbons, It also deteriorates storage stability (especially photostability) in the presence of light and air. In other words, these partially hydrogenated aromatic hydrocarbons are sensitive to light, and in the coexistence of light and air (oxygen), they may cloud the lubricating oil or cause sludge to settle. Furthermore, it is thought that this causes phenomena such as deterioration of the hue, thereby deteriorating the performance of the lubricating oil. An object of the present invention is to provide a photostabilized lubricating oil composition with improved photostability of hydrotreated oil. That is, the present invention provides a lubricant base oil obtained from the above-mentioned hydrotreated oil with (A) about 0.01% to about 3% by weight of the following general formula: (However, R ₁ and R ₂ are tertiary alkyl groups having 4 to 20 carbon atoms, and R ₃ is hydrogen, a hydroxyl group, or a linear primary alkyl group.) A radical chain inhibitor represented by (B) about 0.01% to about 0.5% by weight of the following general formula: (However, R, R′ and R″ are hydrogen, halogen,
It is one selected from the group of alkyl groups, hydroxyl groups, and alkoxy groups. ) and (C) about 0.005% to about 0.2% by weight of thiodipropionic acid ester. Conventionally, US Pat. No. 3,282,842 and US Pat. No. 3,900,410 use lubricating oil as a base oil,
It is disclosed that the oxidation stability is improved by adding a combination of phenol and benzotriazole/benzophenone to this oil, but this has the purpose of improving the photostability of the hydrotreated oil as in the present invention. Moreover, in the present invention, the effect of improving photostability is not sufficient simply by using phenols and benzotriazole/benzophenone in combination. However, in the present invention, the above-mentioned phenols
In addition to (A) and benzophenone (B), thiodipropionic acid ester (C), a peroxide decomposer, is added as a light stabilizer to the hydrotreated lubricating base oil to improve its photostability. It was possible to do so. The radical chain inhibitor represented by the general formula () used in the present invention inhibits radical chains caused by oxidation reactions caused by oxygen in the air. As the radical chain inhibitor represented by the general formula (), 2,6-
Jet-tertiary-butyl-lacresol, 2,6
-Di-ter-shari-butyl-phenol, 2,6
-Di-tertiary-butyl-4-n-decylphenol, 2,6-di-tertiary-butyl-4-
Examples include n-dodecylphenol, 2,6-di-tertiary-butyl-4-n-hexadecylphenol, and other phenols described in US Pat. No. 3,900,410. Among them, 2,6-di-tertiary-butyl-para-cresol, 2,6
-di-tertiary-butyl-phenol is preferred. The amount of the radical chain inhibitor added to the lubricating base oil ranges from about 0.01% to about 3% by weight, preferably from about 0.05% to about 0.2% by weight. The ultraviolet absorber represented by the general formula () used in the present invention includes 2-hydroxy-5-n
-Octoxybenzophenone, 2,2,4,4'-
Tetrahydroxybenzophenone is preferably used. Others 2,4-dihydroxybenzophenone, 2,2', dihydroxybenzophenone, 2-
Benzophenones described in US Pat. No. 3,282,842, such as hydroxy-4-methoxy-4'-bromobenzophenone, can also be used. These ultraviolet absorbers are added in an amount of about 0.01% to about 0.5% by weight, preferably about 0.05% to about 0.3% by weight, based on the lubricating base oil. Preferred thiodipropionate esters for use in the present invention are those in which the ester moiety has 1 to 30 carbon atoms, preferably 6 to 25 carbon atoms. Specific examples of the thiodipropionate ester include distearyl thiodipropionate, dilauryl thiodipropionate, diabiethyl thiodipropionate, and the like, among which distearyl thiodipropionate is most suitable. Thiodipropionic acid ester is used as a peroxide decomposer. Thiodipupionic acid ester is approximately
In the range of 0.005% to about 0.2% by weight, preferably about
It is appropriate to add it in a range of 0.01% to about 0.1% by weight. The lubricating oil base fraction feedstock that constitutes the main component of the composition of the present invention is heated in the presence of a hydrotreating catalyst at a temperature in the range of about 250 to about 410°C and about 40 Kg/cm ² to
Pressure in the range of about 220Kg/ ^cm2 , about 0.3V/H/V to approx.
Approximately 400SCF/at liquid hourly velocity in the range of 3V/H/V
It is preferable that the fraction be selected from hydrocarbon fractions with a boiling point of about 160°C or higher obtained by distilling the hydrotreated oil obtained by contacting B to about 10,000 SCF/B hydrogen, and within this range This includes hydrorefined oils whose hydrogenation conditions range from relatively mild hydrofinishing to severe hydrocracking, and such hydrorefined oils are described in U.S. Pat. It is described in. The present invention is particularly effective when a relatively light fraction is used as the base oil. Note that in the case of hydrogenation under relatively mild reaction conditions and when the hydrotreated oil does not contain a light cracked fraction, distillation may not be performed to obtain the desired fraction. The lubricating oil fraction raw material to be subjected to hydrorefining in the present invention may be any hydrocarbon oil that can be treated with hydrogen.
Any distillate oil or residue may be used, including pyrolysis oil, catalytic cracking light cycle oil and heavy cycle oil, straight-run heavy gas oil, vacuum distillate oil, etc. It is also possible to use oils and even vacuum residue oils. As the catalyst for hydrotreating, any catalyst can be used as long as it has a hydrocracking active component or a hydrogenation active component. Preferably, a Group metal of the Periodic Table of the Elements or/and an oxide or sulfide of a Group metal (for example, an oxide or sulfide of a Group metal such as iron, cobalt, nickel, palladium, platinum, rhodium, iridium, etc.) Among these, sulfides consisting of group metals in combination with group metals such as Nitsuken and molybdenum, cobalt and molybdenum are preferably used. In addition, as a catalyst carrier, alumina, magnesia,
Silica etc. may be used alone or in mixtures, but the silica content should be about 5 to 30% by weight, preferably about 7 to 25% by weight.
Preference is given to alumina and/or magnesia in weight percent. This catalyst carrier supporting the above-mentioned hydrogenation active component is used as a catalyst for hydrogenation treatment. Furthermore, as a catalyst for hydrotreating, a metal of a group of the periodic table and/or a group of metals as described in US Pat. No. 3,944,503 and US Pat. No. 3,843,509 is supported on a carrier, preferably silica-alumina, Catalysts having a pore volume of . A hydrotreating catalyst comprising halogen-containing nickel sulfide and tungsten supported on a support as described in US Pat. No. 928,762 may also be used. In addition to the above-mentioned silica-alumina, the carrier for the hydrotreating catalyst used in the present invention is a silicate aluminate, which is a synthetic zeolite, and has uniform pores. Those ion-exchanged with valent cations can also be used. The present invention as described above uses a lubricating oil distillate raw material such as heavy hydrocarbon oil as an element group metal or (and)
At a temperature in the range of about 250 to about 410°C, about 0 Kg/cm ² to
Pressure in the range of about 220Kg/ ^cm2 , about 0.3V/H/V to approx.
About 0.01 to 3% by weight of a radical chain inhibitor represented by the general formula (); about 0.01 to 0.5% by weight of an ultraviolet absorber represented by the general formula ();
The present invention relates to a lubricating oil composition in which about 0.05 to 0.2% by weight of thiodipropionic acid ester is added, and it is possible to provide a composition that can significantly improve the photostability of the above-mentioned lubricating base oil. . Examples 1 to 6 and Comparative Examples 1 to 6 Temperature (°C) 405 Reaction pressure (Kg/cm ² ) 200 Liquid hourly space velocity (V/H/V) 0.8 H ₂ circulation rate (SCF/B) 900 Arabian light crude oil vacuum distillate oil (Note 1)
was introduced into a reaction column with a fixed bed of hydrotreating catalyst (Note 2) under the above conditions, and a 150 neutral fraction was collected from the reaction product by distillation. This lubricating oil fraction was used as a sample oil to which various additives shown in Table 1 were added, and the storage stability (number of days until sludge was formed) was observed. The results are shown in Table 1. (Note 1) Specific gravity (15/4℃) 0.928 Viscosity (KV＠210〓) cst 14.56 (KV＠100〓) cst 195.0 Viscosity index (VIE) 75 Hue union 8 (+) Wax content weight% Q - 20℃ 8.8 Flash point (℃) 246 Sulfur content (weight%) 2.37 (Note 2) Nickel-molybdenum catalyst with silica-alumina carrier Catalyst composition NiO ₂ 5.7wt% MoO ₃ 14.0 SiO ₂ 13.7 Al ₂ O ₃ remaining amount

【table】

[Table] From the above experimental results, it was found that in addition to a radical chain inhibitor (DBPC) and an ultraviolet absorber (Viosorb-130), the addition of a peroxide decomposer to the lubricant base oil after hydrogenation resulted in a lubricant composition. It is clear that the photostability of the products can be significantly improved.

Claims (1)

[Claims] 1. A lubricating oil fraction feedstock is treated in the presence of a hydrotreating catalyst at a temperature in the range of about 250°C to about 410°C, about
Pressure in the range of 40Kg/ ^cm2 to approx. 220Kg/ ^cm2 , approx. 0.3V/
At liquid hourly space velocities ranging from H/V to approximately 3V/H/V,
(A) about 0.01% to about 3% by weight of the following general formula: (However, R ₁ and R ₂ are tertiary alkyl groups having 4 to 20 carbon atoms, and R ₃ is hydrogen, a hydroxyl group, or a linear primary alkyl group.) Agent (B) about 0.01% to about 0.5% by weight of the following general formula (However, R, R′ and R″ are hydrogen, halogen,
It is one selected from the group of alkyl groups, hydroxyl groups, and alkoxy groups. ) and (c) about 0.005% to about 0.2% by weight of a thiodipropionic acid ester. 2. The lubricating oil composition according to claim 1, wherein the radical chain inhibitor represented by the general formula () is 2,6-di-tertiary-butyl-para-cresol. 3. The lubricating oil composition according to claim 1, wherein the radical chain inhibitor represented by the general formula () is 2,6-di-tert-butyl-phenol. 4 The ultraviolet absorber represented by the general formula () is 2-
The lubricating oil composition of claim 1, which is hydroxy-5-n-octoxybenzophenone. 5 Claim 1, wherein the thiodipyropionic acid ester is distearyl thiodipropionate
The lubricating oil composition described in .