JP2007284646A - Gasoline composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gasoline composition that suppresses the increase in the amount of CO<SB>2</SB>emission due to the worsening of the fuel consumption and has drivability during cold engine operation equal to or higher than that of a gasoline composition comprising hydrocarbons alone in the case where an oxygen-containing compound such as ETBE or the like is blended. <P>SOLUTION: The gasoline composition has a total sulfur content of 10 mass ppm or less, contains an oxygen-containing compound in an amount of 5.0 mass% or less in terms of an oxygen content, has a carbon element content of 86.0 mass% or less, a molar ratio (C/H) of the total of carbon elements to the total of hydrogen elements of 0.55 or less, a 50% distillation temperature of 75-90°C, a 90% distillation temperature of 105-165°C and a research octane number (RON) of 95-102, and satisfies the relationship represented by formula (1): A=IC<SB>5</SB>+IC<SB>6</SB>+IC<SB>7</SB>≥25 and formula (2): B=14×C+T50-0.10×A≤1285. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gasoline composition that emits less carbon dioxide from a vehicle and has good cold-time drivability.

Bioethanol, which is an oxygen-containing compound, and ethyl tertiary butyl ether (hereinafter referred to as ETBE) produced from this material have a high octane number, and preparations are being made for introduction into gasoline against the background of CO ₂ reduction. . Among them, ETBE has a higher octane number at the same oxygen content than ethanol, and does not cause an increase in vapor pressure due to an azeotropic phenomenon even at a low addition amount, and causes phase separation of gasoline when mixed with water. It is easy to handle because it does not occur. It is expected to be introduced to gasoline in 2010 against the background of these merits and the CO ₂ reduction effect. In addition, ETBE-containing gasoline production method (patent document 1, patent document 2) that mixes ETBE with gasoline as an octane number improving base material, and ETBE are mixed with gasoline so that drivability, acceleration and exhaust gas are improved. Many gasolines have been reported (Patent Document 3, Patent Document 4). However, when ETBE is mixed, the fuel consumption deteriorates due to a decrease in the heat generation amount, and the amount of CO ₂ emissions increases accordingly. Also, the air-fuel ratio dilutes and the operability during cold operation deteriorates. However, there are no reports on improvement of hydrocarbon components.

The present invention solves such a problem. Even when an oxygen-containing compound such as ETBE is mixed, an increase in CO ₂ emission due to deterioration in fuel consumption is prevented, and cold-time operability equivalent to or higher than that of hydrocarbons. It is an object to provide a gasoline composition having the following.

Means to solve the problem

The inventors of the present invention have an effect of improving the octane number by mixing ETBE due to the content of the specific component, thereby reducing aromatic components having a relatively high octane number. By reducing this aromatic component, CO ₂ emissions will decrease, but on the other hand, by reducing the aromatic component with a high calorific value, the calorific value of the entire gasoline will decrease, and CO accompanying the deterioration in fuel consumption ₂ There is concern about an increase in emissions. For this reason, as a method of reducing CO ₂ emissions, a method of reducing the proportion of carbon in gasoline by increasing the number of side chains of the benzene ring contained in the aromatic component is a deterioration in fuel consumption due to a decrease in the calorific value of gasoline. It was found that the present invention is effective for suppressing CO ₂ emissions and reducing the CO ₂ emission amount.
That is, the present invention
The total sulfur content is 10 mass ppm or less, the oxygen content of the oxygen compound is 5.0 mass% or less, the carbon element content is 86.0 mass% or less, and the molar ratio of all carbon elements to all hydrogen elements (C / H) is 0.55 or less, 50% distillation temperature is 75 to 90 ° C., 90% distillation temperature is 105 to 165 ° C., research octane number (RON) is 95 to 102, and the following formula ( A gasoline composition satisfying 1) and (2).
A = IC ₅ + IC ₆ + IC ₇ ≧ 25 (1)
In the above formulas (1) and (2), IC ₅ is an isoparaffin content having 5 carbon atoms (volume%), IC ₆ is an isoparaffin content having 6 carbon atoms (volume%), and IC ₇ is an isoparaffin content having 7 carbon atoms (volume%). Volume%), C represents carbon element content (mass%), and T50 represents 50% distillation temperature (° C.).

Moreover, the gasoline composition according to the present invention preferably contains 0.1 to 20.0% by volume of ethyl tertiary butyl ether (ETBE), which has a large effect of reducing vapor pressure, as an oxygen-containing compound.
The gasoline composition according to the present invention has the above-described constitution, so that even if an oxygen-containing compound, particularly ETBE, is mixed, an increase in CO ₂ emission due to deterioration in fuel consumption is prevented, and a gasoline composition consisting only of hydrocarbons. It has excellent cold-time operability that is equal to or better than that of products.

The gasoline composition of the present invention can be prepared by appropriately selecting a gasoline base to be described later and blending it at an appropriate ratio. That is, the gasoline composition of the present invention has a carbon element content of 86.0% by mass or less, and is preferably 85.8% by volume or less, more preferably 85.7% by volume from the viewpoint of reducing CO ₂ emissions. Hereinafter, it is 85.6 volume% or less especially.
The gasoline composition of the present invention has a molar ratio (C / H) of all carbon elements including oxygen-containing compounds to all hydrogen elements of 0.55 or less. 0.54 or less is preferable from the reduction of CO ₂ emission, and 0.53 or less is more preferable.

Moreover, A represented by the following formula (1) is 25 or more, and B represented by the formula (2) is 1285 or less. A is preferably 25.4 or more and B is 1280 or less from the viewpoint of fuel efficiency reduction and driving performance improvement during cold operation.
A = IC ₅ + IC ₆ + IC ₇ (1)
B = 14 × C + T50−0.10 × A (2)
In the formulas (1) and (2), IC ₅ is an isoparaffin component having 5 carbon atoms (volume%), IC ₆ is an isoparaffin component having 6 carbon atoms (volume%), and IC ₇ is an isoparaffin component having 7 carbon atoms (volume%). Volume%), C is carbon element content (mass%), and T50 is 50% distillation temperature (° C.).

  The 50% distillation temperature of the gasoline composition of the present invention is 75 ° C. or higher, preferably 77 ° C. or higher, more preferably 80 ° C. or higher, from the viewpoint of reducing fuel consumption. From the viewpoint of operability when cold, it is 90 ° C. or lower, preferably 88 ° C. or lower, more preferably 87 ° C. or lower. The lower limit of the 90% distillation temperature is 105 ° C or higher, preferably 110 ° C or higher, more preferably 115 ° C or higher, from the viewpoint of reducing fuel consumption. Further, the upper limit of the 90% distillation temperature is 165 ° C. or less, preferably 160 ° C. or less, more preferably 155 ° C. or less from the viewpoint of improving operability during cold operation and maintaining engine cleanliness.

  Furthermore, the gasoline composition of the present invention has RON of 95 or more, preferably 98 or more, particularly preferably 99 or more, from the effect of improving fuel efficiency (efficiency). Increasing the RON of a hydrocarbon compound is usually accompanied by an increase in aromatic content. As a result, the exhaust gas properties deteriorate, the distillation properties become heavier, and the operability during cold operation deteriorates. Therefore, the upper limit of RON is set to 102 or less, preferably 101 or less.

  The sulfur content of the gasoline composition of the present invention is 10 mass ppm or less, preferably 5 mass ppm or less, more preferably 1 mass ppm or less. Sulfur content in gasoline is discharged in the form of sulfur oxides in the exhaust gas, and at that time, one nitrogen oxide removing catalyst of the exhaust gas purification catalyst is poisoned. Fuel is used to create a reducing atmosphere to restore the activity of the poisoned nitrogen oxide removal catalyst. Thus, the sulfur content causes fuel consumption deterioration. Therefore, the fuel efficiency improves as the sulfur content in gasoline decreases.

Further, the gasoline composition of the present invention contains an oxygen-containing compound in an oxygen content of 5% by weight or less. Mixing the oxygen-containing compound is preferable because the carbon element content is reduced and the CO ₂ emission amount is reduced. However, if the amount exceeds 5% by weight, the fuel consumption deteriorates, the amount of CO ₂ emission increases due to the increase in fuel consumption, and the CO ₂ emission reduction effect due to the decrease in carbon element content is reduced. Further, from the effect of reducing CO ₂ emission, the oxygen content is preferably 1% by weight or more, more preferably 2% by weight or more, and particularly preferably 3% by weight or more.

  As the oxygen-containing compound used in the gasoline composition of the present invention, ETBE is preferable. ETBE has a high RON and can reduce the aromatic content while maintaining the RON of gasoline. When ETBE is blended, it is preferably blended so as to contain 0.1 to 20.0% by volume. The lower limit of the ETBE content is preferably 1.0% by volume or more, and more preferably 3.0% by volume or more, from the viewpoint of reducing the aromatic content. In addition, ETBE is more preferably 15.0% by volume or less, and more preferably 8.0% by volume or less, because it tends to generate rust on the metal surface in the presence of water as compared with ethanol and raises the boiling point. The ETBE used in the gasoline composition of the present invention may be imported from overseas or manufactured domestically, but preferably has a purity of 95% or more, and does not contain alcohol other than ethanol. preferable.

  Moreover, although it is not an essential component, ethanol can be mix | blended with the gasoline composition of this invention. As ethanol used in the present invention, any ethanol produced anywhere in Japan or abroad can be used as long as it is an ethanol from which the gasoline composition of the present invention finally meeting the target quality can be obtained. The lower the content of, the better. When ethanol is blended, it is preferably mixed with gasoline in a blending amount of 0.1 to 15.0% by volume.

  Oxygenated compounds other than ethanol and ETBE can also be blended within a range that does not impair the effects of the present invention from the viewpoint of improving RON, using petroleum alternative energy using renewable biomass resources, and the like. Examples of such oxygen-containing compounds that can be used in the gasoline composition of the present invention include methyl tertiary butyl ether (MTBE), ethyl secondary butyl ether (ESBE), tertiary amyl ethyl ether (TAEE), and methanol. The blending amount of these oxygen-containing compounds other than ethanol and ETBE is not particularly limited as long as the oxygen content is kept at 5% by weight or less. However, in order to obtain the desired effect, for example, 0.1-15 in the gasoline composition. What is necessary is just to mix | blend so that it may contain 0.0 volume%.

  The oxygen-containing compound used in this gasoline should have a low content of impurities mixed in the raw materials and the refining process. In particular, the sulfur content is preferably 2 mass ppm or less, and more preferably 1 mass to prevent catalyst poisoning of exhaust gas. ppm or less. Further, the lead vapor pressure (RVP) is preferably 40 kPa or less, but is preferably 30 kPa or less, and more preferably 20 kPa or less, from the effect of reducing the vapor pressure of gasoline.

  Furthermore, the gasoline composition of the present invention preferably has a Reid vapor pressure (RVP) of 93 kPa or less, particularly 65 kPa or less in summer, from the viewpoint of reducing the evaporated gas. If the vapor pressure is too high, the amount of gasoline vapor released into the atmosphere will increase, and if it is too low, the startability of the gasoline vehicle will deteriorate. Practically, it is an index that is particularly susceptible to environmental temperature, and is preferably adjusted according to the season, preferably 44 to 65 kPa in summer and 70 to 93 kPa in winter.

  The gasoline composition of the present invention is not particularly limited to other components, but if the olefin content is high, the oxidation stability generally deteriorates and tends to produce gum and lead to dirt on the intake valve. For this reason, the content of olefin is preferably 25% by volume or less, and more preferably 20% by volume or less.

[Gasoline base material]
Usually, as a gasoline base material constituting the gasoline composition, straight run naphtha obtained by distilling crude oil, desulfurization straight run light naphtha (DS-LG) obtained by distilling and separating it after hydrodesulfurization, And desulfurized straight-run heavy naphtha. Isomerized gasoline having an improved octane number obtained by isomerization of desulfurized straight-run light naphtha is also useful as a gasoline base material. From the desulfurized straight-run heavy naphtha, reformed gasoline can be obtained by reforming with a solid reforming catalyst, and the reformed gasoline can be used as a gasoline base material by adjusting the vapor pressure as it is. . Furthermore, the aroma rich reformate gasoline fraction (AC7, AC9, etc.) having a specific carbon number obtained by distilling the reformate gasoline can also be mentioned. In addition to petroleum fractions from light oil to reduced pressure light oil, degasified oil obtained from the heavy oil indirect desulfurization unit, direct desulfurized oil obtained from the heavy oil direct desulfurization unit, normal pressure residue oil, etc. are catalytically cracked, usually silica Catalytic cracking oil (fluid catalytic cracking gasoline) obtained with a fluidized bed cracking apparatus using an alumina catalyst or a zeolite catalyst, and a fraction that has been distilled to adjust to an appropriate boiling point range, such as light fluid catalytic cracking gasoline (IM-FL) can also be used.

  Further, alkylate gasoline (ALKG) obtained by alkylating butylene fraction and isobutane fraction, gasoline fraction by-produced from various purification processes, and isolated butane, pentane (especially isopentane), or And aroma compounds such as so-called BTX (benzene, toluene, xylene). Furthermore, a gasoline fraction obtained by pyrolyzing asphalt, a gasoline fraction by-produced during naphtha pyrolysis or ethylene polymerization, and the like can be used. Further, a gasoline fraction produced by Fischer-Tropsch (FT) synthesis, a gasoline fraction obtained by decomposing heavier hydrocarbons, and the like can also be used.

  In addition, the above hydrocarbon-based gasoline base material is further used for desulfurization, isomerization, fractional distillation, etc., in order to improve flexibility when preparing gasoline or to prepare a higher quality gasoline composition. The sulfur content, research octane number (RON), boiling point range and the like can be adjusted and used. This hydrocarbon-based gasoline base material is a basic gasoline component constituting the gasoline composition of the present invention.

  The gasoline composition of the present invention is a so-called hydrocarbon gasoline base material, ethanol, ethyl tertiary butyl ether (ETBE), and other ethers and esters compounded in the gasoline composition, so-called An “oxygen-containing compound” is an essential base material, and is contained at an oxygen content of 5.0% by mass or less.

[Combination]
The gasoline composition of the present invention can be prepared by appropriately selecting the above-mentioned gasoline base material and mixing it at an appropriate ratio, and only needs to satisfy the above-mentioned regulations of the gasoline composition. That is, the type, blending amount, and blending order of the gasoline base material used for the preparation of the gasoline composition of the present invention are not particularly limited. Specifically, for example, the gasoline composition of the present invention is as follows. Can be prepared.

A hydrocarbon-based gasoline base material, which is a basic gasoline component constituting the gasoline composition of the present invention, can be selected and blended as follows to prepare a so-called base gasoline. Convenient for the production of gasoline compositions. The amount of catalytic cracking gasoline base material is 0 to 80% by volume of catalytic cracking gasoline in regular gasoline, and the domestic production of regular gasoline is based on catalytic cracking gasoline. Therefore, it is preferably 20% by volume or more, more preferably 40% by volume or more. In premium gasoline, the light catalytic cracked gasoline obtained by distilling and separating the catalytic cracked gasoline is 0 to 50% by volume, preferably 20 to 47% by volume, more preferably 30 to 45% by volume.
In addition, both regular gasoline and premium gasoline, as other gasoline base materials, isomerized gasoline is 0 to 20% by volume, more preferably 2 to 15% by volume, isopentane is 0 to 20% by volume, preferably 2 to 15% by volume. 0 to 40% by volume of toluene, preferably 10 to 38% by volume, more preferably 20 to 37% by volume, and 0 to 30% by volume of alkylate gasoline, preferably 5 to 28% by volume, more preferably 10 to 25%. It is preferable to use 0 to 20% by volume, preferably 1 to 15% by volume of gasoline having a volume%, pyrolysis of asphalt, or gasoline having pyrolyzed naphtha.
Further, as described above, the gasoline composition of the present invention is blended so as to contain 0.1 to 20.0% by volume of ETBE, and reduces the aromatic content while maintaining RON. In addition, oxygen-containing gasoline base materials such as methyl tertiary butyl ether (MTBE), ethyl secondary butyl ether (ESBE), tertiary amyl ethyl ether (TAEE), and methanol are used in terms of RON improvement, effective use of resources, etc. It can mix | blend in the range which does not impair the effect of invention.
Further, the gasoline base material preferably has a sulfur content of 10 mass ppm or less, more preferably 5 mass ppm or less, still more preferably 2 mass ppm or less, and particularly preferably 1 mass ppm or less.
[Other additives]
Furthermore, the gasoline composition of the present invention may contain one or more fuel oil additives known in the art as needed. Although these compounding quantities can be selected suitably, it is preferable to maintain the total compounding quantity of an additive to 0.1 mass% or less normally. Surface ignition of fuel oil additives that can be used in the gasoline composition of the present invention, such as antioxidants such as phenols and amines, metal deactivators such as Schiff compounds and thioamide compounds, and organic phosphorus compounds Detergents such as inhibitors, succinimides, polyalkylamines, polyetheramines and other detergents, antifreezing agents such as polyhydric alcohols or ethers thereof, alkali metal salts or alkaline earth metal salts of organic acids, sulfates of higher alcohols And the like, an anionic surfactant, a cationic surfactant, an antistatic agent such as an amphoteric surfactant, and a coloring agent such as an azo dye. In particular, when ethanol is inferior in oxidation stability, it is effective to add an antioxidant appropriately depending on the amount of gasoline mixed.

  Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to these examples.

A hydrocarbon-based gasoline base material and ETBE shown in Table 1 were prepared and blended at a mixing ratio (volume%) shown in the upper part of Table 2 to prepare fuels of Examples and Comparative Examples.
In addition, the gasoline base material shown in Table 1 was prepared as follows.

C4:
A so-called butane fraction was obtained by distilling and separating the desulfurized liquefied petroleum gas to obtain a fraction containing 95% or more of hydrocarbons having 4 carbon atoms and 73% by volume of normal butane.
DS-LG:
Desulfurized straight-run light naphtha obtained by hydrodesulfurizing a naphtha fraction of Middle Eastern crude oil and distilling the light fraction.
A hydrocarbon having a high isoparaffin content was obtained by reacting a fraction mainly composed of butylene and a fraction mainly composed of isobutane with a sulfuric acid catalyst.
IM-FL:
By decomposing desulfurized light oil and desulfurized heavy oil using a fluidized bed reactor with a solid catalyst, a hydrocarbon with high olefin content, that is, fluid catalytic cracking gasoline (FCCG), is obtained, which is converted into a light fraction and a heavy fraction. It is a light fraction (IM-FL) obtained by distillation separation.

Toluene (TOL):
A reagent product of 99.5% purity (manufactured by Wako Pure Chemical Industries, Ltd.) was used.
When obtaining the desulfurized straight-run light naphtha (DS-LG), after desulfurization, the heavy fraction (desulfurized heavy naphtha) is distilled and separated. This desulfurized heavy naphtha was reformed with a solid catalyst using a moving bed reactor to obtain a hydrocarbon with a high aromatic content, that is, reformed gasoline. This reformed gasoline was separated by distillation to obtain a heavy reformed gasoline fraction (AC9) in which hydrocarbons having 11 or more carbon atoms were 5% by volume or less and hydrocarbons having 9 or 10 carbon atoms were 90% by volume or more. .
ETBE:
A 95% pure reagent product (manufactured by Wako Pure Chemical Industries, Ltd.) was used.

Properties of gasoline base materials and gasoline compositions shown in Tables 1 and 2 were measured by the following methods.
Distillation property: Measured according to JIS K 2254 "Petroleum products-Distillation test method".
Vapor pressure (RVP): Measured according to JIS K 2258 “Crude oil and fuel oil—Vapor pressure test method—Reed method”.
Research method octane number (RON): Measured by the research method octane number test method of JIS K 2280 "Petroleum products-fuel oil-octane number and cetane number test method and cetane index calculation method".
Sulfur content: Determined to 2 digits after the decimal point in accordance with the microcoulometric titration method of JIS K2541 “Crude oil and petroleum products—Sulfur content test method”.
Density: Measured according to JIS K 2249 “Crude oil and petroleum products—Density test method”.
Calorific value: The calorific value (kJ / L) is obtained by multiplying the calorific value (MJ / kg) calculated using the following formula (Duron's formula) by the density.
Calorific value (MJ / kg) = 33.8 × carbon element content (mass%) + 144.3 × (hydrogen content (mass%) − oxygen content (mass%) / 7.94) + 9.42 × sulfur Minute (mass%)
Oxygen content (mass%): The oxygen content was calculated by multiplying the blending amount of the oxygen-containing compound (after mass conversion) by the proportion of oxygen contained in the oxygen-containing compound.

Composition component (hydrocarbon compound): Measured by the gas chromatography method of JIS K 2536 “Petroleum products—component test method”.
[Column tank conditions]
Column type, material: capillary column, methyl silicone (manufactured by HP)
Column diameter and length: 250 μm, 102 m
Initial temperature 5 ° C, holding time 10 minutes, heating rate 2 ° C / min, final temperature 140 ° C
Gas conditions: helium, flow rate 2 mL / min, split ratio 50: 1, makeup amount 50 mL / min,
Sample injection volume: 0.5 μL
Note that the isoparaffin content having 5 carbon atoms (IC ₅ ), the isoparaffin content having 6 carbon atoms (IC ₆ ), and the isoparaffin content having 7 carbon atoms (IC ₇ ) are hydrocarbons corresponding to the respective components obtained by gas chromatography. It was determined by integrating the compound content. The carbon content (C) and the hydrogen content (H) were obtained by integrating from the individual hydrocarbon components obtained by gas chromatography, and the C / H ratio (mol) was calculated.
Further, the values of A and B were obtained by substituting the numerical values obtained as described above into the formulas (1) and (2).

Using the gasoline of Examples 1 to 3 and Comparative Examples 1 to 3, the exhaust gas test of the MPI test vehicle of the specifications shown in Table 1 was conducted in the 10.15 mode using the chassis dynamometer, and CO ₂ emissions and fuel consumption Was measured. The CO ₂ emission amount was obtained from the carbon balance. The results are also shown in Table 2.

The gasoline of Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to an acceleration performance test using an MPI test vehicle using a chassis dynamo device. In the test, after the vehicle was kept in a cold machine (25 ° C.) state, when the accelerator opening was accelerated up to 50% by the automatic driving device (Horiba Seisakusho, ADS7000), the initial speed was 0 to 50 ( km / hour) until the vehicle speed was reached. The results (acceleration time reduction rate) were compared based on the difference in acceleration time relative to the arrival time when the commercial premium gasoline of Comparative Example 1 was used. The results are also shown in Table 2.
The acceleration time reduction rate of the test gasoline was obtained from the following equation.
Acceleration time reduction rate (%) = (arrival time of comparative example 1−arrival time of test gasoline) ÷ (arrival time of comparative example 1) × 100

Claims (2)

The total sulfur content is 10 mass ppm or less, the oxygen content is 5.0 mass% or less, the carbon element content is 86.0 mass% or less, and the molar ratio of all carbon elements to all hydrogen elements (C / H) is 0.55 or less, the 50% distillation temperature is 75 to 90 ° C., the 90% distillation temperature is 105 to 165 ° C., the research octane number (RON) is 95 to 102, and the following formula (1) ) And (2), a gasoline composition,
A = IC ₅ + IC ₆ + IC ₇ ≧ 25 (1)
B = 14 × C + T50−0.10 × A ≦ 1285 (2)
(In the formulas (1) and (2), IC ₅ is an isoparaffin component having 5 carbon atoms (volume%), IC ₆ is an isoparaffin component having 6 carbon atoms (volume%), and IC ₇ is an isoparaffin component having 7 carbon atoms (capacity). %), C represents carbon element content (mass%), and T50 represents 50% distillation temperature (° C.).   The gasoline composition according to claim 1, wherein the oxygen-containing compound is ethyl tertiary butyl ether (ETBE), and the content thereof is 0.1 to 20.0 vol%.