JP2010100732A - Flowability improving agent for biodiesel fuel oil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flowability improving agent for a biodiesel fuel oil, the agent having an effect of improving stability at a low temperature such as an excellent effect of improving a cold filter plugging point and an effect of improving a pour point. <P>SOLUTION: The flowability improving agent for the biodiesel fuel oil comprises an α-olefin polymer having a weight average molecular weight of 50,000 to 500,000, which is obtained by polymerizing an α-olefin mixture (C) comprising an α-olefin (A) having 8 carbon atoms and an α-olefin (B) having 14 to 18 carbon atoms, in a molar ratio (A)/(B) ranging from 10/90 to 50/40. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a flow improver for biodiesel fuel oil having an excellent clogging point improving effect and pour point improving effect, and a biodiesel fuel oil composition containing the same.

In recent years, there are concerns about the depletion of fossil fuels such as oil and coal, and attempts have been made to effectively use natural energy such as sunlight, wind power, and hydropower, and biomass fuel derived from animals and plants. Furthermore, since it contributes to the reduction of carbon dioxide on a global scale, plant-based biomass fuel has attracted particular attention. Plant-based biomass fuel processes plants and uses them as a carbon source. For this reason, the discharged carbon dioxide is again absorbed by plants and trees by photosynthesis and is cycled, so that it is considered that the carbon dioxide concentration at the global level is not affected. Such fuel is positioned as a carbon neutral fuel.
As alternative fuels for gasoline vehicles, plant biomass fuels such as ethanol obtained by fermenting grains such as sugar cane and corn, and ethyl-tertiary butyl ether obtained by reacting ethanol and isobutene have been studied. ing.

  On the other hand, a biomass fuel used in a diesel vehicle is called a biodiesel fuel, and is generally made from animal and vegetable oils and fats. Animal and vegetable oils and fats (triglycerides) are unsuitable for use as diesel fuel as they are because of their high boiling point and high viscosity. For this reason, diesel fuel is processed by converting animal and vegetable oils and fats into physical properties such as boiling range and viscosity that are close to those of light oil. The most commonly used are fatty acid methyl esters and fatty acid ethyl esters derived from animal and vegetable fats and oils. However, biodiesel fuels such as fatty acid methyl esters and fatty acid ethyl esters tend to be less stable at low temperatures than light oil. Since fatty acid esters obtained from animal and vegetable fats and oils have a fatty acid distribution derived from raw oils and fats, the low-temperature characteristics such as clogging points and pour points also vary. In general, biodiesel fuels containing a large amount of saturated fatty acid methyl ester and saturated fatty acid ethyl ester produced using fats and oils with a high saturated fatty acid content as raw materials are inferior in stability at low temperatures. For this reason, there existed a problem that a use time and a use area were restrict | limited.

However, due to the recent energy situation, it is necessary to use fatty acid methyl esters and ethyl esters using various oil raw materials, and fatty acid esters with poor stability at low temperatures using fats and oils with a high saturated fatty acid content. Utilization is also widely studied from the viewpoints of economy and supply stability.
On the other hand, it is known that the middle distillate fluidity improver used for middle distillate oils such as light oil and A heavy oil has little effect on fatty acid esters as it is. Under these circumstances, in order to improve the stability of fatty acid esters at low temperatures, several low-temperature fluidity improvers have been disclosed in which middle-distillate fluidity improvers have been improved for biodiesel fuel oils. ing. For example, Patent Document 1 discloses that an ester polymer of an alcohol having 1 to 22 carbon atoms and (meth) acrylic acid can improve the low temperature stability of a fatty acid methyl ester having a pour point of −5 ° C. or lower. Yes. In addition, Patent Document 2 discloses, as additives for biodiesel fuel oil, alkyl methacrylate having 8 to 30 carbon atoms in an alkyl group, polyoxyalkylene alkyl methacrylate having 1 to 20 carbon atoms in an alkyl group, and carbon in an alkyl group. Copolymers with 1 to 4 alkyl methacrylates are disclosed. Further, Patent Document 3 discloses that ethylene-vinyl ester copolymer having a vinyl ester unit of 17 mol% or more and an alkyl distribution of 5 or more per 100 main chain methylenes as a fluidity improver for methyl ester derived from animals and plants. A polymer is disclosed.

However, in the low temperature fluidity improver using these copolymers, although some fatty acid esters have an effect of improving fluidity at low temperatures, fatty acid esters having various fatty acid compositions, in particular, For fatty acid esters having a high saturated fatty acid ester content, a fluidity improver for biodiesel fuel oil that is not sufficient and has an excellent effect of improving fluidity at low temperatures is desired.
European Patent No. 0563070 JP 2001-524578 A JP 2005-015798 A

  The present invention solves the above-mentioned problems, and its purpose is to improve the fluidity improver for biodiesel fuel oil, which has an excellent effect of improving the stability at low temperatures such as an excellent clogging point improving effect and a pour point improving effect. Is to provide.

As a result of intensive studies to solve the above problems, the present inventors have found that a specific α-olefin polymer exhibits low-temperature stability such as a clogging point improvement effect and a pour point improvement effect of biodiesel fuel oil. Found to improve.
That is, the present invention
(1) α-olefin mixture (A) / (B) having an α-olefin (A) having 8 to 18 carbon atoms and an α-olefin (B) having 14 to 18 carbon atoms having a molar ratio (A) / (B) of 10/90 to 60/40 ( A fluidity improver for biodiesel fuel oil comprising an α-olefin polymer having a weight average molecular weight of 50,000 to 500,000 obtained by polymerizing C),
It is.
(2) The fluidity improver for biodiesel fuel according to (1), wherein the α-olefin mixture (C) has a molar average carbon number of 12.0 to 14.0,
It is.
The present invention also provides a biodiesel fuel composition comprising 10 to 10,000 ppm of the fluidity improver for biodiesel fuel according to (1) or (2) above,
It is.

  The fluidity improver for biodiesel fuel oil of the present invention gives excellent low temperature stability improvement effects such as clogging point improvement effect and pour point improvement effect to biodiesel fuel oils of various fatty acid compositions. can do. In particular, even a biodiesel fuel oil having a high saturated fatty acid ester content can be imparted with a low temperature stability improvement effect such as an excellent clogging point improvement effect and a pour point improvement effect.

Hereinafter, the present invention will be described in more detail.
The α-olefin polymer in the present invention is obtained by polymerizing an α-olefin mixture (C) of an α-olefin (A) having 8 carbon atoms and an α-olefin (B) having 14 to 18 carbon atoms.
Specific examples of the α-olefin having 8 carbon atoms of the component (A) used in the present invention include 1-octene.
Specific examples of the α-olefin having 14 to 18 carbon atoms of the component (B) used in the present invention include 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, and 1-octadecene. These may be used alone or in combination.

  The α olefin mixture (C) used in the present invention has a molar ratio (A) / (B) of the α olefin (A) having 8 carbon atoms and the α olefin (B) having 14 to 18 carbon atoms (A) / (B) = A mixture in the range of 10/90 to 60/40, preferably (A) / (B) = 15/85 to 50/50 α-olefin mixture. In an α-olefin polymer obtained by polymerizing an α-olefin mixture having a molar ratio (A) / (B) of less than 10/90, an effect of improving stability at a low temperature cannot be obtained with respect to biodiesel fuel oil. In an α-olefin polymer obtained by polymerizing an α-olefin mixture having a molar ratio (A) / (B) of greater than 60/40, a stability improvement effect at low temperatures cannot be obtained with respect to biodiesel fuel oil.

  In the present invention, the α-olefin mixture (C) composed of (A) and (B) has a molar average carbon number of 12.0 to 14.0. This is preferable because the effect of improving the stability at low temperatures is increased. More preferably, it is 12.5-13.5.

  The α-olefin polymer of the present invention can be obtained by polymerizing the α-olefin mixture (C). As for the molecular weight of the α-olefin polymer, the weight average molecular weight is 50,000 to 500,000, preferably 50,000 to 300,000. When the α-olefin polymer has a weight average molecular weight of less than 50,000, when it is added to biodiesel fuel oil, the effect of improving stability at low temperatures may not be obtained. Further, when the weight average molecular weight of the α-olefin polymer exceeds 500,000, the viscosity of the α-olefin polymer becomes high, so that it is difficult to suck it up with a pump during operation, and the operation becomes complicated such as dilution with a solvent. Therefore, it is not preferable.

The biodiesel fuel oil in the present invention is not particularly limited, but is preferably a fatty acid ester derived from animal or vegetable oils and fats, more preferably a fatty acid methyl ester or a fatty acid ethyl ester.
The fatty acid ester can be obtained by a conventional method. For example, fatty acid esters (preferably fatty acid methyl esters or fatty acid ethyl esters) obtained by transesterification of animal and vegetable fats and alcohols (preferably methanol or ethanol), or animal and vegetable fats and oils are added to fatty acids and glycerin. After decomposition, glycerin is further removed, and fatty acid esters (preferably fatty acid methyl esters or fatty acid ethyl esters) obtained by directly dehydrating a fatty acid and alcohol (preferably methanol or ethanol) obtained are mentioned. . Animal and vegetable oils and fats used in obtaining the fatty acid ester are not particularly limited. Oil, tall oil, jatropha oil, recovered food oil (waste cooking oil), beef tallow, hydrogenated beef tallow, fish oil, hydrogenated fish oil and the like. These animal and vegetable oils and fats may be used as a mixture of two or more.

  The fluidity improver for biodiesel fuel oil of the present invention is added at 10 to 10,000 ppm with respect to biodiesel fuel oil. If it is less than 10 ppm, it is difficult to obtain the effect of improving stability at low temperatures. Moreover, even if it adds 10,000 ppm or more, the stability improvement effect in the low temperature corresponding to the addition amount is not acquired. As a preferable addition amount, it is 100-8000 ppm, More preferably, it is 200-6000 ppm.

  In addition, the biodiesel fuel oil composition used in the present invention may include middle distillate oil such as light oil and kerosene, gas-to-liquid, biomass-to-liquid, coal-to-liquid, hydrogen as necessary. You may mix chemical decomposition fats and oils.

In the biodiesel fuel oil composition of the present invention, various additives conventionally used as additives for petroleum-based fuel oils, for example, cloud point depressants, rust preventives, oxidation, as well as the flowability improver. Including an inhibitor, a cetane number improver, a metal deactivator, a cleaning dispersant, a flammability improver, a black smoke reducing agent, an antifoaming agent, a hue stabilizer, an anti-icing agent, a sludge dispersant, a marker, etc. I can do it.

Hereinafter, the present invention will be described more specifically with reference to examples.
(1) Production example of α-olefin polymer (Polymer 1)
The following operation was performed in a glove box that was completely replaced with nitrogen and the oxygen concentration was 0.01% or less.
To a 200 mL four-necked flask equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a dropping funnel, 0.15 g of titanium trichloride (Solvay catalyst: manufactured by Tosoh Finechem) was charged. Subsequently, 7.5 ml of a 1 mol / L diethylaluminum chloride / n-heptane solution was sucked in with a syringe.
In a nitrogen atmosphere, the four-necked flask was heated to 90 ° C. in an oil bath. After the temperature rise, 10.0 g of a mixture of 1-octene: 1.0 g (0.0089 mol) and 1-tetradecene: 9.0 g (0.046 mol), which had been dehydrated and replaced with nitrogen in advance, was added from the dropping funnel. did. After the addition, the polymerization reaction was carried out at 90 ° C. for 1.5 hours. After 1.5 hours, 15 mL of 2-methyl-1-propanol was gradually added dropwise to deactivate the catalyst, and the polymerization was stopped.
For the purpose of washing the remaining catalyst, 150 mL of warm water was added to the n-heptane solution in which the polymer was dissolved, followed by washing with warm water (stirring with warm water). After removing the warm water that settled at the bottom, 150 mL of warm water was added again and washing with warm water was performed three more times. Finally, n-heptane in the n-heptane solution in which the polymer obtained was dissolved was distilled off under reduced pressure to obtain 5.0 g of polymer 1.

(Polymers 2 to 10)
The α-olefin described in Table 1 was charged with the weight described in Table 1, and polymerization was performed in the same procedure as in the production method of the polymer 1 to obtain polymers 2 to 10 which were α-olefin polymers. Table 1 shows the molar average carbon number of the α-olefin mixture and the weight average molecular weight of the polymers 1 to 10.

(2) Synthesis example of fatty acid ester (synthesis of waste cooking oil methyl ester)
3000 g of waste cooking oil, 1370 g of methanol, and 7 g of potassium hydroxide were added to a 5 L four-necked flask equipped with a nitrogen inlet tube, a thermometer, and a Dimroth, and a transesterification reaction was performed at 60 ° C. for 3 hours. After the reaction, it was washed 3 times with warm water to separate the lower glycerin aqueous solution. The upper-layer crude waste cooking oil methyl ester was again put into a four-necked flask, 1370 g of methanol and 5 g of potassium hydroxide were added, and the ester exchange reaction was performed again. After completion of the reaction, the mixture was washed with warm water three times, a potassium hydroxide solution was added, and the free fatty acid was washed with neutralized water. Furthermore, after washing | cleaning 3 times with warm water and confirming that the washing | cleaning liquid is neutral, washing with water was complete | finished. The washed ester was depressurized to 70 ° C. and 10 torr and dehydrated for 1 hour to obtain waste cooking oil methyl ester.

(Synthesis of waste cooking oil ethyl ester)
Except that the alcohol was changed from methanol to ethanol, synthesis was performed in the same manner as the above-mentioned waste cooking oil methyl ester to obtain waste cooking oil ethyl ester.

(Synthesis of palm oil methyl ester)
Except having changed waste cooking oil into palm oil, it synthesize | combined in the procedure similar to the said waste cooking oil methyl ester, and obtained palm oil methyl ester.
The fatty acid compositions of the waste cooking oil methyl ester, waste cooking oil ethyl ester, and palm oil methyl ester obtained above were each analyzed by gas chromatography. The analysis results are shown in Table 2 below.

(Measurement of pour point of waste cooking oil methyl ester)
Table 3 below shows the pour point measurement results when the α-olefin polymer was added to the waste cooking oil methyl ester. The pour point was determined in increments of 1 ° C. according to JIS K-2269. In addition, as a fluid improvement agent, the polymers 1-10 of Table 1, the ethylene-vinyl acetate copolymer, and the alkylmethacrylate copolymer were used.

(Measurement of clogging point of waste cooking oil methyl ester)
Table 4 below shows the result of clogging point measurement when the α-olefin polymer is added to the waste cooking oil methyl ester. The clogging point was determined according to JIS K-2288. In addition, as a fluid improvement agent, the polymer 1 and the polymer 5 of Table 1, the ethylene-vinyl acetate copolymer, and the alkylmethacrylate copolymer were used.

(Measurement of pour point of waste cooking oil ethyl ester)
Table 5 below shows the pour point measurement results when the α-olefin polymer was added to the waste cooking oil ethyl ester. The pour point was determined in increments of 1 ° C. according to JIS K-2269. In addition, as a fluid improvement agent, the polymer 2 and the polymer 5 of Table 1, the ethylene-vinyl acetate copolymer, and the alkylmethacrylate copolymer were used.

(Measurement of pour point of palm oil methyl ester)
Table 6 below shows the pour point measurement results when the α-olefin polymer was added to palm oil methyl ester. The pour point was determined in increments of 1 ° C. according to JIS K-2269. In addition, as a fluid improvement agent, the polymer 4 and the polymer 5 of Table 1, the ethylene-vinyl acetate copolymer, and the alkylmethacrylate copolymer were used.

(Measurement of pour point of palm oil methyl ester / middle distillate-mixed fuel)
Table 8 shows the pour point measurement results of the mixed fuel obtained by mixing palm oil methyl ester and the intermediate spilled oil having the properties shown in Table 7 at a weight ratio of 20:80. The pour point was determined in increments of 1 ° C. according to JIS K-2269. In addition, the polymer 5 of Table 1 was used as a fluid improvement agent.

Claims (3)

An α-olefin mixture (C) in which the molar ratio (A) / (B) of the α-olefin (A) having 8 to 18 carbon atoms and the α-olefin (B) having 14 to 18 carbon atoms is 10/90 to 60/40. A fluidity improver for biodiesel fuel oil comprising an α-olefin polymer having a weight average molecular weight of 50,000 to 500,000 obtained by polymerization.
The fluidity improver for biodiesel fuel oil according to claim 1, wherein the α-olefin mixture (C) has a molar average carbon number of 12.0 to 14.0.
A biodiesel fuel composition comprising 10 to 10,000 ppm of the fluidity improver for biodiesel fuel according to claim 1 or 2.