JPH0446997B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a fuel oil quality improver, and more specifically, to hydrocarbon fuel oils, particularly fuel oils such as light oil and A heavy oil. , relates to a fuel oil quality improver that has excellent quality improvement effects such as pour point lowering effect, wax formation and solidification prevention effect.

[Prior Art] Since the advent of oil shocks, the oil imported into Japan has gradually become heavier, and this trend is expected to become stronger in the future worldwide.

On the other hand, the demand for heavy fuel oil is decreasing due to the shift away from petroleum in energy-intensive thermal power generation, but on the other hand, the demand for medium to light fuel oil is increasing because it is mainly used in the civil and transportation sectors. If anything, it tends to increase. In the near future, demand is also expected for fuel oil made from oil sands and oil shale, and fuel oil derived from synthetic oil from coal.

In order to respond to this demand situation, there is a movement to remove some of the heavy distillates and shift to medium or light fuel oils. It is becoming more and more oily.

This type of heavy fuel oil contains a large amount of paraffin with a large molecular weight compared to conventional fuel oil, and the paraffin easily precipitates at low temperatures and loses fluidity at relatively high temperatures. Serious problems arise when used on land.
In addition, even at temperatures that maintain fluidity, wax with a three-dimensional network structure is formed and solidification occurs.
Filters and piping inside fuel oil pipes in diesel engines etc. become clogged, blocking the flow of fuel oil.

Many fluidity improvers have been disclosed to solve these problems, such as condensation products of chlorinated paraffins and naphthalene (U.S. Pat. No. 1,815,022), polyacrylates (U.S. Pat. Specification No. 260453), polyethylene (U.S. Patent Specification No. 3474157), copolymer of ethylene and vinyl acetate (U.S. Patent Specification No. 3048479), copolymer of ethylene and monoolefin (Japanese Patent Application Laid-open No. 60 −
137997), a composition of a linear saturated fatty acid ester of a hydroxyl group-containing nitrogen compound and an ethylene/monoolefin copolymer (Japanese Unexamined Patent Publication No. 137998/1983), and commercially available products such as ethylene-acetic acid. Polymer type additives represented by vinyl copolymers,
Alternatively, long-chain dicarboxylic acid amide-based low molecular weight additives are known.

However, many of these proposed compounds generally have a structure with a polar group attached to the main chain or molecule, and some of them have a good pour point lowering effect. Although there are some, it is not necessarily sufficient to prevent wax precipitation.
In order to achieve both the objectives of lowering the pour point and preventing the precipitation of solids such as wax, it is necessary to increase the amount added, and in this case, the original characteristics such as the combustion characteristics of the fuel oil itself may be impaired. There was a problem that there was.

[Problems to be Solved by the Invention] The present invention has been made based on the above-mentioned circumstances, and its purpose is to solve the problem of fuel oil, especially light oil, A-heavy oil, or similar medium or light fuel oil. When added to fuel oil, it exhibits an excellent pour point lowering effect even in small amounts, can effectively prevent wax formation and solidification, and does not impair the original fuel properties of fuel oil. The object of the present invention is to provide a fuel oil quality improving agent which is extremely advantageous in practice and has an excellent quality improving effect.

[Means for Solving the Problems] As a result of intensive research in order to solve the above problems, the present inventors have found that polystyrene peroxide or polystyrene peroxide having a specific oxygen content and a specific number average molecular weight When a composition containing them is added to fuel oil such as light oil, A heavy oil, or equivalent medium or light fuel oil, it exhibits an excellent pour point depressant effect and prevents the formation and solidification of wax. The present inventors have discovered that the present invention is an excellent fuel oil quality improving agent that prevents the use of fuel and significantly improves the passage through a fuel filter, and does not impair the fuel properties of the fuel oil itself.Based on this knowledge, the present invention was completed.

That is, the present invention provides a fuel oil quality improver containing polystyrene peroxides having an oxygen content of 10 to 30% by weight and a number average molecular weight of 500 to 5,000.

The polystyrene peroxides used in the present invention are polystyrene peroxides having a specific oxygen content and a specific number average molecular weight, and the oxygen content is 10 to 30% by weight,
Number average molecular weight is 500-5000 preferably 500-3500
is within the range of

The preferred range of this oxygen content cannot be unconditionally defined as it varies depending on the type of polystyrene peroxide, but in the case of polystyrene peroxide (peroxide of polystyrene),
Usually, it is preferably in the range of 15 to 25% by weight, and in the case of poly-α-substituted styrene peroxide, it is usually
A range of 15 to 20% by weight is preferred.

The oxygen content of polystyrene peroxides is
If it is less than 10% by weight, the pour point lowering performance at low temperatures will be poor, the effect of preventing the precipitation of solids such as wax may be insufficient, and the fuel properties of the fuel oil itself may be impaired in some cases. There are cases where the quality improvement effect is not sufficiently obtained. On the other hand, those with an oxygen content exceeding 30% by weight are generally difficult to synthesize, or even if they can be synthesized, the cost of synthesis itself is high, so the price of the quality improver obtained is high. Furthermore, in some cases, the fluidity improvement performance may be poor and the original characteristics of the fuel oil may be impaired.

Further, the number average molecular weight is less than 500,
Pour point depression performance is poor, on the other hand, if it exceeds 5000,
Solubility and fluidity decrease.

Suitable examples of the polystyrene peroxides include polystyrene peroxide (peroxide of polystyrene), poly-α-substituted styrene peroxide (peroxide of poly-α-substituted styrene), and the like.

The poly-α-substituted styrene peroxides include poly(α-alkylpolystyrene) peroxides such as poly(α-methylpolystyrene) peroxide and poly(α-ethylpolystyrene) peroxide, and poly(α-phenylpolystyrene).
Examples include poly(α-arylpolystyrene) peroxide such as peroxide, poly(α-methoxypolystyrene) peroxide, poly(α-alkoxystyrene) peroxide such as poly(α-methoxypolystyrene) peroxide, etc. , poly(α-alkylstyrene) peroxide, etc. are suitable, and poly(α-methylstyrene) peroxide is particularly suitable.

The polystyrene peroxides are produced by heating the corresponding polystyrenes, i.e., polystyrene, poly-α-substituted styrene, or their polymers having a predetermined number average molecular weight, using an oxidizing oxygen-containing gas such as air or oxygen. or
Alternatively, it can be synthesized by reacting with other oxidizing peroxides; for example, the synthetic method of Miller and Mayo et al. (AA
Miller and FRMayo, J.Am.Chem.Soc., 78 ,
1017-1023 (1956). ) can be synthesized according to

The fuel oil quality improver of the present invention contains at least one of the above-mentioned polystyrene peroxides, and among them, those containing polystyrene peroxide or polystyrene peroxide and poly-α-substituted styrene peroxide are preferably used. I can do it. Furthermore, among those containing polystyrene peroxide and poly-α-substituted styrene peroxide, the poly-α-substituted styrene peroxide is poly(α-alkylstyrene) peroxide, particularly poly(α-methylstyrene) peroxide. can be suitably used.

It is preferable that the fuel oil quality improver according to the present invention further contains pinane hydroperoxide in addition to the polystyrene peroxides mentioned above. This makes it possible to further improve the pour point depressing performance per amount of polystyrene oxide used, the solubility, and the fluidity of the added fuel oil. It is also possible to add the effect of masking the so-called petroleum odor.

As mentioned above, this pinane hydroperoxide may be used in combination with the polystyrene peroxides, or may be used by being separately added to fuel oil. In either case, the additional improvement effects described above can be expected. In this sense, the fuel oil quality improver of the present invention is preferably used in combination with pinane hydroperoxide.

The amount of pinane hydroperoxide can be set to such an extent that the added fuel oil forms a homogeneous system, but it is usually in the range of 1 to 10 times the amount per 1 part by weight of the polystyrene peroxide used. suitable.

The pinane hydroperoxide can be synthesized by a known method, for example, by passing oxygen or air through pinane while heating it. Pinane peroxide is soluble in various solvents such as aromatic hydrocarbon solvents such as benzene and toluene, and alcohols, and can be used dissolved in these solvents as long as it does not impede the purpose of the present invention. can.

The fuel oil quality improver according to the present invention can also be used after being dissolved or dispersed in a solvent, if desired.

This solvent is not particularly limited as long as it does not interfere with the purpose of the present invention; for example, benzene,
Aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as heptane, octane, and decane;
Examples include fuel oils such as kerosene, light oil, and A heavy oil, alcohols, ketones, esters, and ethers.

The fuel oil quality improver according to the present invention may optionally include antioxidants, corrosion inhibitors, rust preventive agents, antistatic agents, anti-sludge agents, and other fluidity improvers or additives that are added to general fuel oil. Agents can also be used in combination.

The fuel oil quality improver according to the present invention can be used for general hydrocarbon fuel oils, but in particular kerosene, light oil, heavy oil, or similar fraction fuel oils, especially light oil, A heavy oil, or similar fuel oils. It can be suitably used for light and medium quality fuel oil.

In the fuel oil quality improver according to the present invention, the total amount of polystyrene peroxides used is usually 0.1 to 5% by weight, preferably 0.1 to 3% by weight, based on the fuel oil.
It is used by adding in a range of % by weight. This value is
If it is less than 0.1% by weight, the quality improvement effect will be insufficient, such as poor pour point lowering performance and insufficient effect to prevent solid matter precipitation such as wax formation.
On the other hand, even if it is used in an amount exceeding 5% by weight, no further improvement in the pour point lowering performance or the effect of preventing the precipitation of solids such as wax is observed.

[Example] Example 1 Synthesis example of polystyrene peroxide The above synthesis method of Miller and Mayo (AAMiller
and FRMayo, J.Am.Chem.Soc., 78 , 1017−
1023 (1956). ) Polystyrene peroxide was synthesized according to the method.

That is, immediately before use, commercially available styrene (special grade reagent) was washed with dilute alkali and water, dried, and then distilled. Then, 104 g of purified styrene and 0.33 g of azoisobutyronitrile were mixed and reacted, and while maintaining the temperature around 0° C., oxygen was gradually blown into the mixture to absorb 110 g of oxygen. Then, the temperature is gradually raised to 35°C, and the raw materials and other volatile components are distilled off under reduced pressure under a nitrogen stream. 25.5 g of peroxide was obtained.

Fuel oil quality improvement test example Polystyrene peroxide obtained in the above synthesis example was added to 200 g of fuel oil with the following properties obtained by redistilling commercially available light oil (manufactured by Nippon Oil Co., Ltd.) at a content of 0.20% by weight. After heating and stirring at 80° C. for 30 minutes, the mixture was allowed to cool to room temperature, and the pour point was measured according to JIS K2269-1980, and at the same time, the presence or absence of solidification due to wax precipitation was observed.

As a result, the pour point was -30°C or lower, and no wax formation or solidification was observed.

Properties of sample fuel oil Boiling point Initial boiling point 171℃ 10% distillation point 215℃ 50% distillation point 275℃ 90% distillation point 330℃ Final point 351℃ Cloudy point -5℃ Pour point -10℃ Example 2 A fuel oil quality improvement test was carried out in the same manner as in Example 1, except that the content of polystyrene peroxide was changed to 0.35% by weight.

As a result, the pour point was -30°C or lower, and no wax formation or solidification was observed.

Examples 3 to 6 Synthesis example of pinane hydroperoxide It was produced according to the method described in JP-A-61-196961.

In other words, 1380g of pinan and 5.0g of nickel powder.
and heat it to about 100℃ while passing air through it.
Pinane-pinane hydroperoxide mixture 1425g
I got it. According to iodometry analysis, the hydroperoxide content in this mixture was 25%. The reaction solution was distilled under reduced pressure in a nitrogen stream to obtain 370 g of pinane hydroperoxide.

Preparation Example of Fuel Oil Quality Improver 200 g of polystyrene peroxide obtained in the synthesis example of Example 1 and 370 g of pinane hydroperoxide obtained in the above synthesis example were mixed to prepare a fuel oil quality improver.

Fuel oil improvement test example In Example 1, the fuel oil improver prepared above was used instead of polystyrene peroxide, and the amount added was as follows:
A quality improvement test was conducted in the same manner as in Example 1, except that they were added in amounts of 0.05, 0.1, 0.15, and 0.2% by weight, respectively.

As a result, the pour point was -30°C or lower in all cases, and no wax formation or solidification was observed.

Example 7 Synthesis example of poly-α-methylstyrene peroxide The aforementioned synthesis method of Miller and Mayo et al. (AA
Miller and FRMayo, J.Am.Chem.Soc., 78 ,
1017-1023 (1956). ) Poly-α-methylstyrene peroxide was produced according to the method described in (1).

That is, the same procedure as in Example 1 was carried out except that 100 g of oxygen was absorbed per 1180 g of α-methylstyrene.

As a result, 29.0 g of poly-α-methylstyrene peroxide having an oxygen content of 15% by weight and a number average molecular weight of 810 was obtained.

Fuel oil quality improvement test example In Example 1, poly-α-styrene hydroperoxide obtained in the above synthesis example was used instead of polystyrene hydroperoxide, and the amount added was
It was carried out in the same manner except that it was added at a concentration of 0.3% by weight.

As a result, the pour point was -30°C, and no wax formation or solidification was observed.

Examples 8 to 10 Preparation example of fuel oil quality improver 10 g of polystyrene peroxide obtained in the synthesis example of Example was mixed with 10 g of poly-α-methylstyrene peroxide obtained in the synthesis example of Example 3. Mix with 50g of pinane hydroperoxide,
A fuel oil quality improver was prepared.

Fuel oil quality improver test example Same as in Example 1 except that the fuel oil quality improver obtained in the above preparation example was used instead of polystyrene peroxide, and the amounts added were 0.1, 0.2, and 0.3% by weight, respectively. It was carried out as follows.

As a result, the pour point was −30° C. or lower regardless of the amount added, and no wax formation or solidification was observed.

Examples 11 to 13 Synthesis example of polystyrene peroxide Same as Example 1 except that the amount of azobisisobutyronitrile was changed to 0.10 g under the conditions for synthesizing polystyrene peroxide used in Example 1.
It was carried out in the same way.

As a result, oxygen content 15%, number average molecular weight 750
31.0 g of polystyrene peroxide was obtained.

Preparation example of fuel oil quality improver Polystyrene peroxide obtained in the above synthesis example
A fuel oil quality improver was prepared by mixing 30.0 g of the pinane hydroperoxide obtained in the synthesis example of Example 3 with 10.0 g of the same.

Fuel oil quality improver test example In Example 1, fuel oil with the following properties obtained by redistilling commercial product A heavy oil was used as the fuel oil, and the fuel oil quality obtained in the above preparation example was used in place of polystyrene peroxide. Using a modifier, the amount added was 0.3 as polystyrene peroxide, respectively.
The same procedure as in Example was carried out except that 0.4 and 0.5% by weight were added.

As a result, the pour point was -15°C at any amount added, and no wax formation or solidification was observed.

Properties of sample fuel oil Boiling point Initial boiling point 245℃ 10% distillation point 271℃ 50% distillation point 293℃ 90% distillation point 341℃ Final point 370℃ Cloud point +3℃ Pour point -6℃ [Effects of the invention ] Since the fuel oil quality improver of the present invention contains polystyrene peroxides having a specific oxygen content and a specific number average molecular weight, it is suitable for use in fuel oil, especially medium quality oil such as light oil and A heavy oil. , when added to light distillate fuel oil, can significantly lower the pour point of fuel oil, and can also effectively prevent wax formation and solid matter precipitation, and Because it does not lose its original characteristics,
To prevent clogging of filters and piping, and at the same time to significantly improve the passability of filters, and to effectively solve various problems associated with storage and transportation of distillate fuel oil with a relatively high boiling point at low temperatures. It is possible to significantly improve the quality of fuel oil. Furthermore, since even high-boiling fractions can be effectively utilized, the production amount of high-quality fuel oil can be significantly increased.

That is, according to the present invention, it is possible to provide a fuel oil quality improver that is extremely advantageous in practice as described above.

Claims (1)

[Scope of Claims] 1. A fuel oil quality improver characterized by containing polystyrene peroxides having an oxygen content of 10 to 30% by weight and a number average molecular weight of 500 to 5000. 2. The fuel oil quality improver according to claim 1, wherein the polystyrene peroxide is polystyrene peroxide and/or poly-α-substituted styrene peroxide. 3. The fuel oil quality improver according to claim 2, wherein the poly-α-substituted styrene peroxide has an oxygen content of 10 to 20% by weight. 4. The fuel oil quality improver according to claim 2 or 3, wherein the poly-α-substituted styrene peroxide is poly-α-alkylstyrene peroxide. 5. The fuel oil quality improver according to claim 4, wherein the poly-α-alkylstyrene peroxide is poly-α-methylstyrene peroxide.