JPH033716B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Hydrocarbon liquid mixtures have various combinations of compounds to be mixed, and their uses are wide-ranging, with fuel being a typical example. For example, in order to increase the fuel efficiency of heavy oil and expand its use in the light oil field, a small amount of methanol may be mixed into the oil, or fine powder may be mixed with methanol or pulverized coal for the purpose of safely and efficiently transporting pulverized coal. Practical applications such as dispersion in hydrocarbon oil are expected. However, in all applications, it is necessary to add various surfactants to maintain the stability of the hydrocarbon liquid mixture so that phase separation does not occur. It has been proposed that copolymers or their saponified products can be used as suitable stabilizers.

However, when this stabilizer is used, it has poor storage stability at low temperatures, so there is a risk that the dispersion state will be destroyed and phase separation will occur during storage in winter or handling in cold regions, and there is still room for further improvement. One thing became clear.

However, the present inventors have noticed that the performance changes greatly depending on the composition ratio of ethylene and vinyl acetate, the average degree of polymerization, and even the average degree of saponification.
Confident that there is a region where the stabilizing effect can be sufficiently demonstrated even at low temperatures, we conducted research and found that the ethylene content was 50 mol% or more, the average saponification degree was 95 mol% or less, and the average polymerization degree was 1500 or less. filed a patent application for the ethylene-vinyl acetate copolymer or its saponified product. The present inventors further thought that not only the composition of the above-mentioned copolymer but also its molecular structure may have a large effect on stability, and as a result of conducting intensive research on the relationship between molecular structure and stability effect, we found that ethylene - It has been found that a vinyl acetate copolymer or a saponified product thereof having a branched structure in which a specific number of methyl terminal side chains are bonded to the methylene group has even better low-temperature storage stability. That is, the present invention provides a hydrocarbon-based liquid mixture consisting of a combination of at least two types of alcohol, solid hydrocarbon, and liquid hydrocarbon, with an ethylene content of 30 mol% or more and an average degree of saponification.
An ethylene-vinyl acetate copolymer or a saponified product thereof is added which has an average degree of polymerization of 95 mol% or less and 1500 or less and has a structure in which 4 to 20 methyl terminal side chains are branched per 100 methylene groups. The present invention relates to a fuel composition comprising: Moreover, when a polyvinyl acetate resin having an average degree of saponification of 80 mol % or less and an average degree of polymerization of 1500 or less is further added to the composition, a fuel composition with further improved stability can be obtained.

The stabilizer used in the present invention must have a structure in which 4 to 20 methyl-terminated side chains are branched per 100 methylene groups on the methylene groups in the ethylene-vinyl acetate copolymer or its saponified product. If the number of methyl-terminated side chains is less than 3, the stabilizing effect of the present invention cannot be obtained, while if it is 20 or more, there is a practical problem in terms of production of the copolymer, and the dispersion effect is reduced.

Such a copolymer or a saponified product thereof can be easily obtained by copolymerizing ethylene and vinyl acetate according to a conventional method, and the number of methyl-terminated side chains is mainly adjusted by the polymerization temperature. For example, when 4 to 9 methyl terminal groups are introduced, a polymerization temperature of about 100 to 150°C is required, and when 10 or more methyl end groups are introduced, a polymerization temperature of 150°C or higher is required.

In the copolymer, it is necessary to limit the ethylene content, average degree of saponification, and average degree of polymerization, and the ethylene content to obtain a stable dispersion effect is 30 mol% or more, preferably 50 to 95 mol%. , particularly preferably 75 to 95 mol%, average saponification degree 95 mol% or less, preferably 60 mol% or less, average polymerization degree 1500
Below, it is desirable to specify preferably 500 or less.

Among the previously reported ethylene-vinyl acetate copolymers, by specifying the composition, degree of polymerization, and structure of the copolymer, it is possible to use a stabilizer that can be left at low temperatures for an extremely long period of time. The copolymer used in the present invention has a unique performance in that it can sufficiently exhibit its stabilizing effect even when the copolymer is heated. In addition, as mentioned above, there is no fear of phase separation or destruction of the dispersion system even if the mixture is stored for a long period of time by using the stabilizer, but it is also suitable for handling in terms of fluidity. It also has the advantage of having a high viscosity.

In the ethylene-vinyl acetate copolymer or its saponified product, a small amount of other unsaturated monomers that can be copolymerized with ethylene and vinyl acetate may be copolymerized.

Further, the ethylene-vinyl acetate copolymer or its saponified product can be added in any form of powder, block, or solution.

The amount of the copolymer or its saponified product varies depending on the type of the mixed liquid or its purpose, so it cannot be absolutely specified, but it is usually in the range of 0.005 to 5% by weight based on the entire composition. Appropriate.

In the present invention, the average saponification degree is further 80 mol%.
Hereinafter, when a polyvinyl acetate resin having an average degree of polymerization of 1500 or less is used in combination, stability is further improved.

Among the polyvinyl acetate resins mentioned above, partially saponified polyvinyl acetate products with an average saponification degree of 60 mol% or less, particularly preferably 20 to 60 mol%, and an average polymerization degree of 50 to 1000, that is, low saponification products and low polymerization degree Partially saponified products of are particularly effective.

In addition to the vinyl acetate group and the hydroxyl group, a small amount of other functional groups may be included in the molecule of the polyvinyl acetate resin.

Furthermore, the polyvinyl acetate resin can be added in the form of powder, block, or solution, and as a solution, it can be added in an alcoholic solvent such as a methanol solution, an ethanol solution, or a methanol/methyl acetate solution. A solution is suitable, and it is of course possible to use water and other solvents that are compatible with the alcohol in combination, if necessary.

The amount of the resin to be added varies somewhat depending on the type of the mixed liquid or its purpose, so it cannot be absolutely specified, but it is usually in the range of 0.005 to 5% by weight based on the total composition. The effect is particularly remarkable when the polyvinyl acetate resin is used in an amount of 5 to 90% by weight based on the ethylene-vinyl acetate copolymer or its saponified product.

In the present invention, methanol is typically used as the alcohol, but higher alcohols such as ethanol, propanol, and betanol can also be used. Examples of solid hydrocarbons include coal, asphalt, coal tar, and pitch.

Furthermore, liquid hydrocarbons include gasoline (for automobiles and aviation), jet fuel oil, kerosene, light oil,
Heavy oils (A heavy oil, B heavy oil, C heavy oil), lubricating oils, etc. are exemplified, but according to the present invention, in particular, the boiling point is
Remarkable effects can be obtained for hydrocarbons at temperatures above 200℃.

The hydrocarbon liquid mixture to which the present invention is applied may be any combination of two or more of alcohol, solid hydrocarbons, and liquid hydrocarbons, and in short, the mixture is liquid. It is necessary. As long as it is liquid, it may be in a dispersed state such as a slurry or emulsion, or it may be in an apparently uniform solution state.

From a practical standpoint, the preferred combination is gasoline/
These include methanol, light oil/methanol, heavy oil/methanol, coal/methanol, coal/ethanol, asphalt/methanol, etc., but particularly heavy oil/methanol or asphalt/methanol exhibits a remarkable effect. The mixing ratio in the mixture is not particularly limited and may be selected from any range depending on the purpose. For example, when mixing methanol with heavy oil, methanol of 30% by weight or less is practically used.

When preparing the composition of the present invention, there is no restriction on the mixing means, and in short, at least two types of alcohol, solid hydrocarbon, and liquid hydrocarbon and ethylene-vinyl acetate copolymer or its saponified product or polyvinyl acetate are used. It is only necessary to mix the system resins while stirring.
The order of addition is arbitrary.

Further, during such operations, optional compounds such as various surfactants, various additives such as combustion aids, and water may be used in combination as necessary.

The composition thus obtained is extremely stable, exhibits excellent stability even when stored at low temperatures for a long period of time, and has appropriate fluidity, making it useful as a fuel.

Hereinafter, the present invention will be explained in more detail by giving examples. Parts or percentages are by weight unless otherwise specified.

Example 1 100 parts of diesel oil was charged into a stainless steel container at room temperature and mixed with 10 parts of methanol, ethylene content 90 mol%, average degree of polymerization 50, and a branched polymer having 8 methyl-terminated side chains per 100 methylene groups. A composition was obtained by charging 0.4 part of ethylene-vinyl acetate copolymer. This composition was completely homogeneous. When the composition was left at room temperature for 30 days, its transmittance was measured and found to be 21%. Further, when the composition was left at 5° C. for 30 days and its transmittance was measured, it was 45%.

However, the transmittance was measured at 20°C at a wavelength of 430 mμ using a cell with a thickness of 2 mm. The lower the transmittance, the more uniform the dispersion state.

Example 2 100 parts of light oil was charged into a stainless steel container at room temperature, and while stirring, 5 parts of methanol, 0.1 part of water, ethylene content 85 mol%, average degree of polymerization 60, and 9 methyl terminal side chains per 100 methylene groups were added. 0.3 part of ethylene-vinyl acetate copolymer and average saponification degree of 45 mol%,
Partially saponified polyvinyl acetate with an average degree of polymerization of 400
A composition was obtained by charging 0.08 parts. The transmittance after being left at room temperature for 30 days was 5%, and the transmittance after being left at 5°C for 30 days was 7%.

Example 3 2.0 parts of ethylene-vinyl acetate copolymer having an ethylene content of 87 mol%, an average degree of polymerization of 100, and 7 methyl-terminated side chains per 100 methylene groups, and 100 parts of C heavy oil
parts were mixed with stirring. This system was homogeneous. No phase separation was observed even after being left at 5°C for 30 days.

Examples 4 to 5 The same experiment as in Example 2 was conducted except that asphalt (Example 4) and C heavy oil (Example 5) were used instead of light oil in Example 2. The system was homogeneous. 5
No phase separation was observed even after being left at ℃ for 30 days.

Example 6 100 parts of C heavy oil was charged into a stainless steel container at room temperature and mixed with 10 parts of methanol, 0.2 parts of water, ethylene content 90 mol%, average degree of saponification 55 mol%, average degree of polymerization 70 per 100 methyl groups. Saponified ethylene-vinyl acetate copolymer with 9 methyl-terminated side chains
0.7 part was added to obtain a composition. No phase separation was observed even after being left at 5°C for 30 days.

Control Example The same experiment as in Example 1 was carried out except that an ethylene-vinyl acetate copolymer having two methyl-terminated side chains per 100 methylene groups was used. Transmittance is 25% when left at room temperature for 30 days, 30% at 5℃
The transmittance when left in the sun was 60%.

Claims (1)

[Scope of Claims] 1. A hydrocarbon liquid mixture consisting of a combination of at least two types of alcohol, solid hydrocarbon, and liquid hydrocarbon, with an ethylene content of 30 mol% or more and an average saponification degree of 95 mol% or less The degree of polymerization is 1500 or less,
A fuel composition in which an ethylene-vinyl acetate copolymer or a saponified product thereof having a branched structure of 4 to 20 methyl terminal side chains per 100 methylene groups is added to the methylene group. 2. The fuel composition according to claim 1, which uses an ethylene-vinyl acetate copolymer or a saponified product thereof having an ethylene content of 50 mol% or more. 3 A hydrocarbon-based liquid mixture consisting of a combination of at least two types of alcohol, solid hydrocarbon, and liquid hydrocarbon, (1) ethylene content of 30 mol% or more, average saponification degree of 95 mol% or less, average polymerization degree 1500 or less, and the methylene group contains 4 to 100 methylene groups.
Adding an ethylene-vinyl acetate copolymer with a branched structure of 20 methyl terminal side chains or its saponified product and (2) a polyvinyl acetate resin with an average saponification degree of 80 mol% or less and an average polymerization degree of 1500 or less. A fuel composition made of 4. The fuel composition according to claim 3, which uses an ethylene-vinyl acetate copolymer or a saponified product thereof having an ethylene content of 50 mol% or more.