JPS58134188A - Fuel oil composition - Google Patents

Abstract

PURPOSE:To obtain a fuel oil composition having excellent fluidity, by adding a specific ethylene copolymer and a specific n-paraffin to a middle fractions fuel oil having a specific boiling point range. CONSTITUTION:(A) 100pts.wt. of a middle fractions fuel oil having a boiling point range of 175-360 deg.C is mixed with (B) 0.005-5pts.wt. of an ethylene copolymer (e.g. ethylene.propylene copolymer) having an ethylene content of 65- 95mol% and a number-average molecular weight of 2,000-20,000 and (C) 0.2- 1.5pts.wt. of a 26-27C n-paraffin (i.e. n-hexacosane or n-heptacosane).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to middle distillate fuel oil compositions with improved flowability.

When middle distillate fuel oils, such as light oil and A heavy oil, are used or stored at low temperatures, wax crystals contained in the oil may grow and clog pipes, or the viscosity of the entire oil may increase dramatically. Problems such as the fluid not flowing often occur. To avoid such troubles, fluidity improvers (FIOW Izpr+ve, r p-■
) is used.

This type of additive is thought to improve the fluidity of oil at low temperatures by changing its crystal structure and morphology through eutectic or adsorption with the wax in the oil.

Currently, this type of additive is attracting attention as a potential solution to the expected future heavier fuel oil, as introduced in numerous documents and patents, and some are beginning to be used in Japan as well. However, the current situation is that there is still a need for improvement in terms of performance of the additives introduced so far.

In other words, even if the pour point test used in past performance evaluations shows that the effect of additive use is apparently significant, this test does not necessarily correspond to the actual performance. However, there were many cases where problems such as those mentioned above occurred. Regarding such items, the clogging point of a low temperature filter (Cold Filter) is said to be a more practical test method that has rapidly attracted attention in recent years.
When subjected to the PluggingPoint CFP'P) test and evaluated, almost no additive blending effect was observed, indicating that the aforementioned control of wax crystals was insufficient.

For example, a number of fuel oil compositions with improved fluidity have been proposed in the past by blending various fuel oils with various ethylene copolymers or even wax mixtures (for example, British Patent Nos. 848,777 and 9'9). .3744, same 1
．． No. 264638, No. 1486077, U.S. Patent No. 3
No. 166387, No. 3443917, No. 34997
According to these proposals, by combining various fuel oils with various ethylene copolymers or wax mixtures, It is said that an improvement in liquidity has been observed. It is true that according to the above-mentioned pour point test, it can be said that a considerable improvement has been achieved in many combinations, but according to the above-mentioned CFPP test, there are some cases in which no acceptable improvement is observed. It was almost.

The present inventors investigated the relationship between the properties of fuel oil and the properties of ethylene copolymer as an additive in detail in order to obtain a fuel composition with truly improved fluidity despite its high boiling point range. As a result of investigation, 100 middle distillate fuel oils with a boiling point range of 170°C to 400°C and an end point of 360°C or higher
Ethylene content is 75 to 85 mol% based on weight parts,
A fuel composition containing 5 to 5.0 parts by weight of ethylene copolymer o, oo having a number average molecular weight of 2,000 to 20,000 was found. However, in light oil grades having a boiling point slightly lower than that of fuel oil, no phenomenon of CFPP reduction was observed even when the above-mentioned ethylene copolymer was blended.

Furthermore, the above-mentioned British Patent No. 1264638 and British Patent No. 1
The formulation of a wax mixture as taught in No. 264,684 had no effect on the same machine.

The present inventors have found that even in the above-mentioned light oil grade, CFP
The present invention was arrived at as a result of studying prescriptions for lowering P. That is, the present invention has an ethylene content of 65 to 95 mol %, a number average molecular weight of 200
0 to 20,000 ethylene copolymer 0. [l 05
This is a fuel oil composition comprising 9.2 to 5.0 parts by weight of n-paraffin having an order prime number of 26 to 27.

The middle distillate fuel oil used in the present invention has a boiling point range of 175
to 560°C. Even if a fuel oil with a higher end point than this is used, no synergistic effect is observed when using the ethylene copolymer and the above-mentioned n-paraffin in combination, and on the contrary, the addition of n-paraffin may cause an adverse effect. Further, even if a fuel oil having a boiling point range lower than that mentioned above is used, the effect of the combination of the above additives is similarly not observed. The middle distillate fuel oil used in the present invention generally exhibits P, P values of about -20.0°C to 0°C, and CFPP values of about -15 to 0°C.

The ethylene copolymer used in the present invention has an ethylene content of 65 to 95 mol%, preferably 65 to 90 mol%.
mol %, particularly preferably 7 to 85 mol %, number average molecular weight of 2,000 to 20,000, preferably 30
00 to 15,000. Even if an ethylene copolymer is used with an ethylene content lower than the above range, the effect will be small; conversely, an ethylene copolymer with an ethylene content higher than the above range will have poor solubility in fuel oil and will even have a negative effect. Further, even if an ethylene copolymer having a number average molecular weight larger than the above range or smaller than the above range is used, the effect is similarly small.

The ethylene m polymer can be selected from copolymers of ethylene and α-olefins or copolymers of ethylene and vinyl monomers. Examples of the α-olefin include propylene, 1-butene, 1-pentene, 1
Examples include -hexene, 1-octene, 1-decene, 1-tetradecene, 4-methyl-1-pentene, and two or more of these. Examples of the vinyl monomer include vinyl acetate, methyl acrylate, ethyl acrylate, and methyl methacrylate.

As an ethylene copolymer, especially the Q value (uw/Mn)
is preferably 3 or less.

In the present invention, n-paraffin having 26 to 27 carbon atoms, ie, n-hexacosane and/or n-hebutacosane, is used together with the ethylene copolymer. Even if an n-paraffin with a larger number of carbon atoms or a smaller number of carbon atoms is used, the effect will be small, and even if an n-paraffin mixture containing a small amount of n-paraffin with 26 to 27 carbon atoms is used, the desired effect will not be achieved. I can't get it. When using n-paraffins with 26 to 27 carbon atoms, it is preferable not to use other n-paraffins in combination as much as possible, but even if they are mixed, the amount of other n-paraffins used should be It should be kept to 1/2 or less of n-paraffin.

The ethylene copolymer is used in an amount of 0.005 to 5.0 parts by weight, preferably 0.01 parts by weight, per 100 parts by weight of middle distillate fuel oil.
It is blended in a proportion of 1.0 to 1.0 parts by weight. Also, the number of carbon atoms is 2
The 6 to 27 n-paraffin is blended in an amount of 0.2 to 1.5 parts by weight, preferably 0.3 to 1.0 parts by weight, per 100 parts by weight of fuel oil.

If the amount of n-paraffin added is too large, CFPP tends to increase, which is not preferable.

The composition of the present invention may contain a corrosion inhibitor, an antioxidant, a stabilizer, a dispersant, and other additives as required.This will be explained below with reference to Examples. Table 1 shows the properties of the ethylene electrolyte composite used in the examples, and Table 2 shows the properties of the fuel oil. In Table 1, the ethylene-propylene copolymer was synthesized according to the method disclosed in Japanese Patent Application No. 56-2603. In addition, ethylene vinyl acetate co-electronic “coalescence” is Es5o
The results of Examples 1 to 6 and Comparative Examples 1 to 12 with F'low Improver 4% 5920 or less are △C, F, P,
P, (scale of low-temperature fluidity imparting effect = (additive-free fuel oil CFPP) - (additive-added fuel oil (CFPP)) is summarized in Table 3.

Example 1 A solution was prepared in which 0.035 parts by weight of copolymer (A) and 0.5 parts by weight of n-hebutacosan were added to fuel oil, and the PPP was measured. (Jour
nal of the In5titude of P
etroleum Vol, 52. Measured according to the method described in A510).

Example 2 The same procedure as in Example 1 was carried out except that n-hexacosane was used instead of n-heptacosane.

Example 3 The same procedure as in Example 1 was carried out except that copolymer (B>) was used instead of copolymer (A).

Example 4 The same procedure as in Example 1 was carried out except that copolymer (C) was used instead of copolymer (A).

Example 5 Using fuel oil (ii) instead of fuel oil in Example 1, n-
Example 6 The same procedure was carried out except that n-hexacosane was used instead of heptacosane. In Example 1, copolymer (H) was used instead of copolymer (A), and n-hexacosane was used instead of n-heptacosane. The same procedure was performed except that .

Example 7 In order to clarify the combined effect of copolymer and n-paraffin, Example 1.5 was prepared by adding copolymer unit and n-paraffin, respectively.
- C, F, P, and P when paraffin was added alone were measured and shown in Table 4.

Comparative Example 1 The same procedure as in Example 1 was carried out except that n-f tracosane was used instead of n-heptacosane.

Comparison, Example 2 The same procedure as in Example 1 was carried out except that n-octacosane was used instead of n-hebutacosane.

Comparative Example 3 In Example 1, the amount of n-hebutacosan J:mp4;)~44
Paraffin wax at ℃ (nc 1a~”'3
It is an n-paraffin in the range of 2"'24~c28wo4
The same procedure was carried out except that 4.3% content (gas chromatography analysis result) was used.

Comparative Example 4 In Example 1, heavy fuel oil (n-hebutacorn was replaced with
The same procedure was carried out except that 1.5 parts by weight of "'-024 to c28 (16.9% content: gas chromatography analysis result)" was added.

Comparative Example 5 The same procedure as in Example 1 was carried out except that fuel oil (1) was used instead of fuel oil and n-hexacon was used instead of n-heptacosane.

Comparative Example 6 Using fuel oil (IV) instead of fuel oil in Example 1, n-
The same procedure was carried out except that n-hexacosane was used instead of hebutacosane.

Comparative Example 7 The same procedure as in Example 1 was carried out except that n-hexacosane was added in an amount of 0.1 part by weight instead of n-hebutacosane.

Comparative example 8. 1 The same procedure as in Example 1 was carried out, except that 2.0 parts by weight of Rehe1xacosane was added instead of n-heptacosane.

Comparative Example 9 The same procedure as in Example 1 was carried out except that the copolymer side (D) was used instead of the copolymer side (D).

Comparative Example 10 The same procedure as in Example 1 was carried out except that copolymer (E) was used instead of copolymer (A). The fuel oil solution was cloudy at room temperature.

Comparative Example 11 The same procedure as in Example 1 was carried out except that copolymer (F) was used instead of Shu.

Example 12 The same procedure as in Example 1 was carried out except that copolymer (()l was used instead of copolymer (A)).

Claims (1)

[Claims] (1) For 100 parts by weight of middle distillate fuel oil with a boiling point range of 175 to 360°C, the ethylene content is 65 to 9.
5 mol%, number average molecular it 2000 to 20000
0.005 to 5.0 parts by weight of ethylene copolymer and 0.2 to 1 part of n-paraffin having 26 to 27 carbon atoms.
．． A fuel oil composition containing 5 parts by weight.