JPH10237469A - Pour point improver for fuel oil and fuel oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a fuel oil improved in low-temperature pour and reduced in the settlement of deposited wax by adding a partial ester having a specified chemical tractor or an adduct thereof with an alkylene oxide and an adduct prepared by grafting an unsaturated dicarboxylic acid ester onto an ethylene/ vinyl saturated carboxylate copolymer to a middle distillate. SOLUTION: 1-20wt.% at least one member selected among a partial ester (A) of at least trihydric alcohol with a 12-30C fatty acid, a partial ester (B) of an adduct of the alcohol with an alkylene oxide with a 12-30C fatty acid and an adduct of component A with an alkylene oxide is mixed with 10-99wt.% adduct obtained by grafting an unsaturated dicarboxylic acid ester onto an ethylene/vinyl saturated carboxylate copolymer to obtain a pour improver for a fuel oil. Examples of fuel oils to which it is added include various gas oils (diesel fuel oil) and heavy fuel oil A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to additives for improving the flowability of fuel oils and fuel oil compositions.

[0002]

2. Description of the Related Art When a middle distillate oil such as diesel fuel oil or heavy fuel oil A is exposed to a low temperature in winter or in a cold region, paraffin wax or a wax-like substance contained therein is precipitated, and a fuel piping system is formed. Clogging of the filter, and solidification of the fuel in the piping system causes problems such as an inability to start the engine and the combustion device and a stop of the engine.

[0003] In order to solve these problems relating to fluidity at low temperatures, a number of methods have heretofore been proposed for adding a vinyl ester copolymer of ethylene-saturated carboxylic acid to fuel oil. For example, it is described in JP-B-39-20069, JP-B-48-23165, and JP-A-59-136391. Also, an unsaturated dicarboxylic acid ester adduct of an ethylene-vinyl carboxylate copolymer and a method of adding these adducts in combination with an ethylene-vinyl acetate copolymer, an ethylene-acrylic acid ester copolymer, etc. JP-B-58-39472], a complete ester of a polyoxyalkylene ether of alkanetriol and a linear saturated fatty acid, an ethylene-vinyl acetate copolymer, an ethylene-acrylate copolymer and a long-chain alkyl group. (Meth) acrylic acid copolymer and the like [Japanese Patent Publication 2-5]
No. 1477], a method of adding a fatty acid ester of polyoxyalkylene glycol and a combination of these esters and an ethylene-vinyl acetate copolymer [Japanese Patent Application Laid-Open No. Sho.
7-177092] A method of adding an incomplete ester of a fatty acid with an alkylene oxide adduct of a trihydric or higher polyhydric alcohol or a partial ester thereof [Japanese Patent Laid-Open No. Sho 6]
1-181892] has been proposed.

[0004]

However, in recent years, the demand for middle distillate has increased, and as a result of meeting this demand, the distillation properties of diesel fuel oil and heavy oil A have narrow distillation boiling ranges, that is, It is a narrow cut middle distillate. Further, by performing hydrodesulfurization for reducing the sulfur content in the gas oil, there is a tendency that the properties become narrower distillation properties. In order to improve the fluidity of these middle distillate oils at low temperatures, the conventionally used method of adding an ethylene-vinyl acetate copolymer is insufficient to improve the fluidity, and the precipitated wax precipitates. In some cases, problems such as filter clogging may occur. Also,
A method of adding a complete ester of a polyoxyalkylene ether of alkanetriol with a linear saturated fatty acid and a combination of the complete ester and a (meth) acrylic acid copolymer containing a long-chain alkyl group; In the method of adding the unsaturated dicarboxylic acid ester adduct of the acid vinyl copolymer, the sedimentation of the precipitated wax is small, but the effect of improving the fluidity at low temperatures is small.

[0005]

Means for Solving the Problems As a result of intensive studies on this problem, the present inventors have found that a partial ester having a specific chemical structure or an alkylene oxide adduct of a partial ester can be obtained from an ethylene-saturated vinyl carboxylate copolymer. It has been found that the addition of an unsaturated dicarboxylic acid ester graft admixture improves the fluidity at low temperatures and reduces the sedimentation of precipitated wax. That is, the present invention relates to a polyhydric alcohol (a1)
Partial esters (A) with fatty acids (a2) to (a),
1) alkylene oxide adduct (b1) and carbon number 1
At least one selected from partial esters (B) with 2 to 30 fatty acids (a2) and alkylene oxide adducts (C) of (A), and ethylene-saturated carboxylic acid vinyl ester copolymer (d1) Unsaturated dicarboxylic acid ester (d2) graft adduct (D), and if necessary, complete ester of ethylene oxide adduct of glycerin and behenic acid (e1), ethylene-saturated carboxylic acid vinyl ester copolymer (e2), alkyl It is a fluidity improving additive for fuel oil comprising one or more compounds (E) selected from the group consisting of (meth) acrylate polymers (e3).

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific examples of the trihydric or higher polyhydric alcohol (a1) of the present invention include glycerin, polyglycerin, trimethylolethane, trimethylolpropane,
Trimethylolbutane, pentaerythritol, dipentaerythritol, sorbitol, sorbitan, monosaccharides, disaccharides, trisaccharides and the like. Preferred are pentaerythritol, sorbitol and sorbitan.

The fatty acid having 12 to 30 carbon atoms (a2) forming the partial ester (A) and the partial ester (B) of the present invention
Specific examples include fatty acids purified from natural oils such as coconut oil, palm oil, peanut oil, olive oil, castor oil, rapeseed oil, beef tallow, and whale oil. Preferably, it is an unsaturated fatty acid having 16 to 22 carbon atoms. If the number of carbon atoms is less than 12, or more than 30, the solubility in diesel fuel oil may cause a problem.

Specific examples of the alkylene oxide adduct (b1) forming the partial ester (B) and the alkylene oxide forming the alkylene oxide adduct (C) of the present invention include ethylene oxide, propylene oxide and mixtures thereof. Is raised. Preferred is ethylene oxide. The addition mole number of these alkylene oxides is usually 1 to 7 moles, preferably 1 mole.
５5 mol. If it exceeds 7 mol, the effect of improving the fluidity at low temperatures tends to decrease.

The partial ester (A) can be produced by subjecting the above (a1) and (a2) to an esterification reaction using sulfuric acid or p-toluenesulfonic acid as a catalyst. Partial ester (B) is obtained by adding alkylene oxide 1 to (a1).
It can be produced by esterifying an adduct (b1) obtained by adding 7 mol in the presence of a catalyst such as potassium hydroxide and a fatty acid (a2) with sulfuric acid, paratoluenesulfonic acid or the like as a catalyst. Further, (C) can be produced by subjecting 1 to 7 mol of alkylene oxide to addition reaction with partial ester (A) using potassium hydroxide or the like as a catalyst.

Preferred partial esters (A) include pentaerythritol, sorbitan, polyhydric alcohols of sorbitol, oleic acid, linoleic acid, erucic acid,
Monoesters and diesters of linolenic acid with fatty acids. Preferred partial esters (B) are monoesters and diesters of pentaerythritol, sorbitan, and 1 to 5 moles of ethylene oxide adduct of sorbitol with oleic acid, linoleic acid, erucic acid, and linolenic acid. Preferred alkylene oxide adducts (C) are 1 to 5 mol of ethylene oxide adducts of pentaerythritol, sorbitan, monoesters and diesters of sorbitol with oleic acid, linoleic acid, erucic acid, and linolenic acid.

As a specific example of the ethylene-saturated carboxylic acid vinyl ester copolymer (d1) forming the graft adduct (D), the saturated carboxylic acid vinyl ester is 10 to 10%.
40% by weight, and has a number average molecular weight of 500 to 20,000.
0 and a copolymer in which the saturated vinyl carboxylate is at least one selected from the group consisting of vinyl acetate, vinyl propionate, vinyl butyrate, vinyl neononanoate and vinyl neodecanoate. Preferably, it is an ethylene-vinyl acetate copolymer having a number average molecular weight of 2,000 to 10,000 and a vinyl ester of a saturated carboxylic acid being vinyl acetate. When the content of the saturated carboxylic acid vinyl ester is more than 40% by weight, the precipitated wax tends to settle. When the content is less than 5% by weight, the solubility in diesel light oil or the like is lost. On the other hand, if the number average molecular weight is less than 500, the effect of improving the fluidity at low temperatures tends to deteriorate, and if the number average molecular weight exceeds 20,000, the viscosity becomes high and practicality is lost. Specific examples of the unsaturated dicarboxylic acid ester (d2) forming the graft adduct (D) include unsaturated dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, and itaconic acid;
Monoester or diester with an alcohol having 1 to 22 carbon atoms, preferably dimethyl maleate, dibutyl maleate, diisobutyl maleate, dioctyl maleate, di-2-ethylhexyl maleate, dioctadecyl maleate, maleate Diicosyl acid, dimethyl fumarate, dibutyl fumarate, diisobutyl fumarate, dioctyl fumarate, di-2-ethylhexyl fumarate, dioctadecyl fumarate, diicosyl fumarate, and the like. The graft adduct (D) is obtained by homogenizing an ethylene-saturated carboxylic acid vinyl ester copolymer (d1), an unsaturated dicarboxylic acid ester (d2) and a small amount of a radical generating catalyst (organic or inorganic peroxide, azo compound). , And the mixture is usually heated to 100 ° C. or higher to cause a reaction. The reaction ratio between (d1) and (d2) is 100/5 to 20/100 (weight ratio), preferably 100/10 to 50/100 (weight ratio).
If the ratio of (d1) / (d2) is more than 100/5 and (d1) is greater, the solubility tends to be insufficient. Also, 20/1
When (d1) is less than 00, the fluidity improving effect tends to decrease.

In the present invention, if necessary, a complete ester (e1) of an ethylene oxide adduct of glycerin and behenic acid, an ethylene-saturated carboxylic acid vinyl ester copolymer (e2), and an alkyl (meth) acrylate polymer (e3) ) Can be used in combination with one or more compounds (E) selected from the group consisting of: Complete ester of ethylene oxide adduct of glycerin and behenic acid (e1)
As a specific example of glycerol ethylene oxide 1
Triester of 50 mol adduct and behenic acid.
Ethylene-saturated carboxylic acid vinyl ester copolymer (e
As specific examples of 2), ethylene is 50 to 75% by weight, the number average molecular weight is 500 to 5,000, and the saturated vinyl carboxylate is vinyl acetate, vinyl propionate, vinyl butyrate, vinyl neononanoate, One or more ethylene-saturated carboxylic acid vinyl ester copolymers selected from the group consisting of vinyl neodecanoate are exemplified. Preferably, ethylene is 55 to 70% by weight, the number average molecular weight is 2,000 to 4,000, and the vinyl ester of a saturated carboxylic acid is selected from the group consisting of vinyl acetate, vinyl neononanoate and vinyl neodecanoate. Or more copolymers. Specific examples of the alkyl (meth) acrylate polymer (e3) include a methacrylate or acrylate having a hydrocarbon group having 1 to 22 carbon atoms or a copolymer (weight average molecular weight of 1,000 to 1,0).
00,000), preferably having 12 to 12 carbon atoms.
Weight average molecular weight of 5,000 having 18 alkyl groups
~ 200,000 (co) polymers of methacrylate or acrylate.

The total amount of the partial ester (A), the partial ester (B) and the alkylene oxide adduct (C) in the additive of the present invention is 1 to 20% by weight, preferably 2 to 20% by weight.
10% by weight. If it is less than 1% by weight or more than 20% by weight, the effect of improving the fluidity at low temperatures tends to decrease. The amount of the adduct (D) is 10 to 99% by weight,
Preferably it is 10 to 95% by weight. If it is less than 10% by weight, the precipitated wax tends to settle, and if it exceeds 99% by weight, the effect of improving the fluidity at low temperatures is small.

Specific examples of the fuel oil of the present invention include JIS No. 1 gas oil, JIS No. 2 gas oil, and JIS gas oil obtained by ordinary distillation.
S3 gas oil, JIS special No. 3 gas oil; desulfurized gas oil produced from ordinary crude oil through a hydrodesulfurization process; obtained by blending this hydrodesulfurized gas oil with a straight run gas oil (light oil before the hydrodesulfurization process) JIS No. 1 light oil obtained from light oil fraction, JI
S2 light oil, JIS No. 3 light oil, and JIS special No. 3 light oil. Further, heavy fuel oil A produced by mixing the above various light oil fractions with distillation residue, extract and the like can be mentioned.
Preferably, JIS No. 2 gas oil, JIS No. 3 gas oil, JIS
JIS No. 3 gas oil, particularly preferably JIS No. 2 gas oil, JIS No. 3 gas oil, JIS No. 3 gas oil having a sulfur content of 0.2% by weight or less obtained by blending hydrodesulfurized gas oil and straight-run gas oil.
No. light oil.

The fuel oil of the present invention may contain other known additives. These known additives include detergents (ethylene oxide adduct of butylamine, ethylene oxide adduct of butanol), lubricity improvers (glycerin monolinoleate, dimer acid, etc.), antioxidants and the like.

【Example】

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited thereto. The fluidity of fuel oil at low temperature is determined by the pour point (JIS K22
69), and filter clogging temperature (JIS K228)
8). The lower the pour point and the filter plugging temperature, the better the fluidity at low temperatures. The sedimentation degree of the precipitated wax was measured by weighing 100 ml of the sample oil in a 100 ml measuring cylinder with a stopper, and visually observing the degree of sedimentation of the precipitated wax after standing at a temperature of 2 ° C. below the cloud point of the sample oil for 15 hours. Then, the capacity of the wax portion was read and evaluated. Capacity 1
It was judged that the closer to 00 ml, the less the sedimentation. Further, the number average molecular weight was measured by a vapor pressure osmosis method, and the weight average molecular weight was measured by gel permeation chromatography using polystyrene as a standard sample. The total content of monoester and diester was calculated from the area of the gel permeation chromatogram (GPC). The molecular weight of the polyhydric alcohol was calculated from the hydroxyl value, and the molecular weight of the fatty acid was calculated from the acid value, and the reaction molar ratio was calculated.

Table 1 shows the properties of the middle distillate used in the evaluation.

[0018]

[Table 1]

Production Example 1 [Production of partial ester of oleic acid of sorbitan] 0.1 mol of sorbitol, 0.1 mol of oleic acid, and 0.5 wt% of paratoluenesulfonic acid as a catalyst were added with sorbitol and oleic acid. The reactor was charged into a reaction vessel and heated to 220 ° C. while passing nitrogen gas through to produce a partial ester of sorbitan and oleic acid (SE1). The acid value was 3.5, and the content of monoester and diester by GPC was 55% by weight. Production Example 2 [Production of linoleic acid partial ester of ethylene oxide (4 mol) adduct of pentaerythritol] 0.1 mol of pentaerythritol and 0.3% by weight of potassium hydroxide of pentaerythritol charged as a catalyst in a reaction vessel. throw into. After heating to 120 ° C., ethylene oxide was added to the mixture.
4 mol are added little by little. After the addition, the mixture was further reacted for 1 hour, potassium hydroxide was removed with activated clay, and a 4-mol ethylene oxide adduct of pentaerythritol was produced. 0.1 mol of the obtained ethylene oxide adduct, 0.1 mol of linoleic acid, and 0.5% by weight of p-toluenesulfonic acid as a catalyst, based on the total amount of the ethylene oxide adduct and linoleic acid, were introduced into the reaction vessel. The mixture was heated to 200 ° C. while passing gas, and a partial ester of linoleic acid with a 4-mol ethylene oxide adduct of pentaerythritol (S
E2) was prepared. The acid value was 2, and the total content of monoesters and diesters by GPC was 61% by weight. Production Example 3 [Production of 1 mol adduct of oleic acid partial ester of sorbitan with ethylene oxide] 0.1 mol of partial ester of sorbitan and oleic acid produced in Production Example 1, and input amount of partial ester of sorbitan and oleic acid as a catalyst Is charged into the reaction vessel. 1
After heating to 20 ° C., 0.1 mol of ethylene oxide is added little by little. After the addition, the mixture was further reacted for 1 hour, potassium hydroxide was removed with activated clay, and 1 mol of an ethylene oxide adduct of a partial ester of sorbitan and oleic acid (S
E3) Manufactured. The acid value was 2. Production Example 4 [Production of behenic acid partial ester of pentaerythritol] 0.1 mol of pentaerythritol and 0.1 mol of behenic acid
As a catalyst, 0.5 wt% of paratoluenesulfonic acid based on the charged amounts of sorbitol and oleic acid were charged into a reaction vessel, and heated to 200 ° C. while passing nitrogen gas, to behenate partial ester of pentaerythritol (SE4). ) Manufactured. Production Example 5 [Di-2-maleic acid maleate of ethylene-vinyl acetate copolymer]
Production of Ethylhexyl Adduct] 100 g of ethylene-vinyl acetate copolymer having an ethylene content of 90% by weight and an average molecular weight of 3,000, and di-2-ethylhexyl maleate 100
g, 2 g of dicumyl peroxide was charged into the reaction vessel, and heated to 150 ° C. while passing nitrogen gas to cause a graft reaction, and a maleic acid copolymer of ethylene-vinyl acetate copolymer was obtained.
A 2-ethylhexyl adduct (SG1) was produced. Production Example 6 [Production of dibutyl maleate adduct of ethylene-vinyl acetate copolymer] 100 g of ethylene vinyl acetate copolymer having an ethylene content of 80% by weight and an average molecular weight of 6,000, 500 g of dibutyl maleate, dicumyl peroxide 1
g into a reaction vessel and 150 ° C. while passing nitrogen gas through.
To give a graft reaction to produce an ethylene-vinyl acetate copolymer dibutyl maleate adduct (SG2). Production Example 7 [Production of dimethyl maleate adduct of ethylene-saturated vinyl carboxylate terpolymer] Ethylene having an ethylene content of 70% by weight, an average molecular weight of 3,000, a vinyl acetate content of 25% and a vinyl neononanoate content of 5% -100 g of a saturated vinyl carboxylate terpolymer, dimethyl maleate 20
0 g and dicumyl peroxide 4 g were charged into the reaction vessel,
The mixture was heated to 150 [deg.] C. while passing a nitrogen gas through to carry out a graft reaction to produce an ethylene-saturated vinyl carboxylate terpolymer copolymer of dimethyl maleate (SG3).

Comparative Production Example 1 [Production of partial ester of sorbitan capric acid] A sorbitan capric acid ester (RE1) was produced in the same manner as in Production Example 1 except that oleic acid was replaced by capric acid. Comparative Production Example 2 [Production of oleic acid partial ester of ethylene glycol] A sorbitan capric acid ester (RE2) was produced in the same manner as in Production Example 1 except that sorbitol was replaced with ethylene glycol.

Examples 1 to 7 and Comparative Examples 1 to 5 The partial esters and the like shown in the Production Examples were blended at the blending ratios shown in Table 2 to obtain a 70% by weight solution of white kerosene.
No. 7 fluidity improving additives (S1 to S7) for fuel oil were prepared. Also blended as shown in Table 2, 70 kerosene with white kerosene
The fluidity-improving additives (R1 to R4) for fuel oils of Comparative Examples 1 to 4 were prepared as solutions by weight.

[0022]

[Table 2]

GE-1 is a complete ester of behenic acid with 4 moles of ethylene oxide adduct of glycerin;
A-1 has an ethylene content of 63% by weight, a number average molecular weight of 2,
500 ethylene-vinyl acetate copolymer. Also,
PMA-1 has a weight average molecular weight of 20,000 and 14 carbon atoms.
Is a polymer of a saturated / linear alkyl methacrylate.

S1 to S7 and R1 to R4 were evaluated oil A,
A predetermined amount was added to the evaluation oil B, and a pour point (PP) and a filter clogging point (CFPP) were measured. Evaluation oil C
To a predetermined amount, and the degree of sedimentation of the precipitated wax was evaluated. The results are shown in Tables 3 and 4.

[0025]

[Table 3]

[0026]

[Table 4]

As is evident from Table 3, the fluidity improver for fuel oils of the present invention has an excellent effect of improving fluidity at low temperatures and has a low degree of sedimentation of precipitated wax.

[0028]

EFFECT OF THE INVENTION The fluidity improving additive for fuel oil of the present invention is excellent in fluidity improving effect at low temperature and has little sedimentation of precipitated wax, so that it can be used without causing problems even in cold regions. The production of light oil and heavy oil A becomes easy.

Claims (12)

[Claims] 1. An alkylene oxide adduct (b) of a partial ester (A) of a trihydric or higher polyhydric alcohol (a1) and a fatty acid having 12 to 30 carbon atoms (a2), and (a1)
1) at least one selected from partial esters (B) of fatty acids (a2) having 12 to 30 carbon atoms and alkylene oxide adducts (C) of (A), and ethylene-saturated carboxylic acid vinyl ester copolymers A fluidity improving additive for fuel oil comprising an unsaturated dicarboxylic acid ester (d2) graft adduct (D) of the coalescence (d1). 2. The fluidity improving additive according to claim 1, further comprising a complete ester (e1) of an ethylene oxide adduct of glycerin and behenic acid, an ethylene-saturated carboxylic acid vinyl ester copolymer (e2), and an alkyl. A fluidity-improving additive for fuel oil, which uses together one or more compounds (E) selected from the group consisting of (meth) acrylate polymers (e3). 3. The polyhydric alcohol (a1) is one or more compounds selected from the group consisting of pentaerythritol, sorbitol and sorbitan.
The fluidity improving additive for fuel oil according to the above. 4. The fatty acid (a2) has 12 to 22 carbon atoms.
The fluidity improving additive for fuel oil according to any one of claims 1 to 3, which is an unsaturated fatty acid. 5. The alkylene oxide adduct (b1)
5. The fluidity improving additive for fuel oil according to claim 1, wherein the alkylene oxide of the alkylene oxide adduct (C) is ethylene oxide, propylene oxide or a mixture thereof. 6. 6. The alkylene oxide adduct (b1)
The average number of moles of the alkylene oxide added therein is (a
The flow improver for a fuel oil according to any one of claims 1 to 5, wherein the hydroxy group of 1) is 0.25 to 5 per hydroxy group. 7. The alkylene oxide adduct (C) has an average addition mole number of alkylene oxide of 0.25 to 5 per hydroxy group of (A).
7. The fluidity improving additive for fuel oil according to any one of the above items 6. 8. The total content of the monoester and diester of (A), (B) and (C) is (A), (B),
The amount is at least 50% by weight based on the total amount of (C).
8. The fluidity improving additive for fuel oil according to any one of items 7 to 7. 9. The ethylene-saturated carboxylic acid vinyl ester copolymer (d1) has a number average molecular weight of 500 to 2
An ethylene-vinyl acetate copolymer having a vinyl acetate content of 5 to 40% by weight, wherein (d1) / (d
The fluidity improving additive for a fuel oil according to any one of claims 1 to 8, wherein the reaction ratio of 2) is from 100/5 to 20/100 (weight ratio). 10. The total amount of (A), (B) and (C) is 1 to 20% by weight or more based on the whole additive.
10. The fluidity improving additive for fuel oil according to any one of items 9 to 9. 11. A fuel oil containing the fluidity improver for a fuel oil according to any one of claims 1 to 10. 12. The fuel oil according to claim 10, which has a sulfur content of 0.2% by weight or less.