JPH0519599B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a solidified liquefied petroleum gas composition that is easy to handle and evaporates more slowly than in a liquid state. The present invention relates to a solidified composition of fuel.

(Prior art) Conventional gas lighters use propane, butane, and other fuels that are gaseous at room temperature and pressure, but these are all pressurized by their own vapor pressure in a closed container. When the container is opened, it vaporizes and is used as fuel. However, if the container is opened due to breakage or the like, it will instantly vaporize and a large amount will become gas, and great care must be taken when filling. In particular, when filling, for example, if the cooling filling method is used, liquefied butane gas easily vaporizes, so it must be cooled to -50 to -60°C, which has disadvantages such as the tendency to vary the amount of gas when used at room temperature. It was hot.

(Problems to be Solved by the Invention) The present inventors have completed the present invention as a result of various studies in order to solidify the liquefied petroleum gas, which is difficult to handle, and make it easier to handle. Therefore, an object of the present invention is to provide a solidified liquefied petroleum gas composition that is easy to handle.

(Means for Solving the Problems) That is, the present invention is obtained by adding a small amount of resin to a mixed solvent consisting of liquefied petroleum gas, a solid agent, a solvent compatible with the liquefied gas, and an aprotic solvent. It is a solidified liquefied petroleum gas composition, and the liquefied petroleum gas in the present invention is a petroleum-based or natural gas-based hydrocarbon that is gaseous at normal temperature and pressure, and is made into a liquid by compressing or simultaneously cooling it. Primarily propane or butane, but also liquefied butane (butane-butylene mixture) and liquefied propane (propane-propylene mixture) used as fuel. As the solid agent or gelling agent for solidifying these liquid gases, dibenzylidene sorbitol, tribenzylidene sorbitol, or nuclear substituted derivatives thereof can be used, but a mixture of dibenzylidene sorbitol and tribenzylidene sorbitol is most preferred. These sorbitol compounds are white powders obtained by dehydrating and condensing benzaldehyde or its nuclear substituted product with D-sorbitol in the presence of an acid catalyst, and these are white powders obtained by dehydrating and condensing D-sorbitol with benzaldehyde or its nuclear substituted product in the presence of an acid catalyst. Dissolves in proton-based solvents at high concentrations.

By the way, when solidifying liquefied petroleum gas, it is possible to dissolve the gelling agent in an aprotic solvent and mix this solution with liquefied petroleum gas, but the liquefied petroleum gas to be solidified is Since it is nonpolar, it has no compatibility with dimethylformamide or N-methyl-2-pyrrolidone, which are aprotic polar solvents, and therefore cannot be solidified by this method. Furthermore, if a gelling agent such as dibenzylidene sorbitol is added to a solvent that is compatible with propane, butane, etc., gelation occurs and it is impossible to form a solution. As a result of conducting various studies to improve this point, we found that a specific solvent that is compatible with propane, N-butane, isobutane, etc. and dimethylacetamide or N-methylacetamide, which is an aprotic polar solvent, were used.
It has been discovered that dibenzylidene sorbitol or tribenzylidene sorbitol, etc. is dissolved in a mixed solvent with 2.pyrrolidone or a mixture thereof, and liquefied petroleum gas is added thereto to solidify the liquefied petroleum gas. That is, examples of the solvent include acetone, linear primary alcohols having 8 to 18 carbon atoms obtained by the oxo method (hereinafter referred to as oxo alcohols), and unsaturated aliphatic alcohols such as oleyl alcohol. be able to. The mixing ratio of the solvent compatible with liquefied petroleum gas and the aprotic polar solvent in this mixed solvent can be varied depending on the combination of each solvent, but for example, in the case of dimethylacetamide and oxo alcohol, the former is 75 parts to 65 parts (by weight), and the latter is most preferably between 25 and 35 parts (by weight). If dimethylacetamide exceeds 75 parts by weight, it will have poor compatibility with the liquefied petroleum gas to be solidified, and if it is less than 65 parts by weight, it will become solid. Even if a solidifying agent such as dibenzylidene sorbitol is dissolved, it does not become a solution and the solidifying agent itself gels, making it impossible to use. In addition, adding ethyl cellosolve to the mixed solvent has the effect of preventing the solidifying agent solution from rapidly gelling when cooled.
Any amount typically between 1 and 5 parts can be used.

When it comes to fuel for gas lighters, it is important that the lighter's flame does not generate soot, and for this reason aromatic solvents cannot be used. Furthermore, since plastic containers are generally used for gas lighter containers, it is thought that a solvent that does not dissolve plastic is preferable, but among the above-mentioned solvents, oxo alcohol and oleyl alcohol are most preferred.

The amount of dibenzylidene sorbitol or tribenzylidene sorbitol dissolved is in the range of 3 to 25 parts, preferably 5 to 20 parts by weight, per 100 parts by weight of the mixed solvent. If it is less than 3 parts, the strength of the solidified liquefied gas obtained will be weak, and if it is more than 25 parts, the mixed solvent will gel when cooled. Further, the required amount of dibenzylidene sorbitol or tribenzylidene sorbitol is from 0.5 parts by weight to 4 parts by weight based on 100 parts by weight of the composition to be solidified.
If it is less than 0.5 parts by weight, the solidified product of the liquefied gas obtained will be weak and soft in the form of jewelery, and if it is more than 4 parts by weight, it will precipitate and cause whitening.

Next, it is necessary to add a small amount of resin to increase the strength of the solidified product, but there are very few resins that dissolve in the liquefied gas that is solidified, such as rosin, ester gas, rosin derivatives, isoprene rubber, polybutadiene, etc. is used, and the amount added is 0.01 to 15 parts per 100 parts (weight) of liquefied petroleum gas to be solidified.
parts, preferably 0.1 parts to 5 parts (by weight), more preferably 0.2 parts to 2 parts; if it is less than 0.01 parts, it will be too soft and difficult to mold, and if it is more than 15 parts, it will be difficult to dissolve and it will become cloudy. will occur.

Next, the present invention will be explained with reference to Examples. All numbers below are weights.

Example 1 Butane gas is cooled to -10℃ and liquefied.
Add 0.5 part of rosin to 95.5 parts and stir to dissolve. Separately, prepare a mixed solvent consisting of 65 parts of dimethylacetamide and 25 parts of oxo alcohol, add 9 parts of dibenzylidene sorbitol to it, heat it to 80°C to completely dissolve it, and then add 1 part of ethyl cellosolve. This solution can exist in a solution state without immediately gelling even when cooled to -10°C. Next, butane 90 mixed with the rosin obtained earlier
When mixed with 10 parts of a mixed solution of dimethylacetamide, oxo alcohol and ethyl cellosolve in which dibenzylidene sorbitol is dissolved, a gel is formed and a slightly hard solid liquefied gas is obtained. It is possible to cut this into any shape and seal it in a container. Although it is necessary to perform all of the above operations at -10℃ to prevent the vaporization of butane as much as possible, solidified butane gas is extremely stable and will gradually vaporize if left as is. It can be seen that it forms small lumps and evaporates very slowly.

Example 2 Using propane gas instead of butane gas in Example 1, polybutadiene was dissolved at -45°C to prepare the following liquid.

1st liquid: 95.5 parts of liquefied propane, 0.5 parts of polybutadiene. Similarly, mix the following composition and heat to 80°C to dissolve and make 2nd liquid.

2 parts Tribenzylidene sorbitol 3 parts Dibenzylidene sorbitol 2 parts N-methyl-2-pyrrolidone 80 parts Acetone 13 parts When the 2 parts are cooled to -45°C and the 1 part at -45°C is mixed, it immediately solidifies and becomes hard agar. get something like that.

Example 3 In the same manner as in Example 1, prepare the following solution at -20°C.

Part 1: Liquefied isobutane 99 parts Ester gum 0.5 parts Pine resin 0.5 parts In the same manner, mix the following compositions and heat to 80℃ to completely dissolve and make Part 2.

Part 2 Dibenzylidene sorbitol 10 parts N-methyl-2-pyrrolidone 50 parts Dimethylacetamide 18 parts Oleyl alcohol 20 parts Ethyl cellosolve 2 parts Next, when parts 1 and 2 are mixed at -20°C, solidification occurs immediately. A solid isobutane composition is obtained.

(Effects) The solidified liquefied petroleum gas composition of the present invention is extremely stable and easy to handle, and can also be molded into a desired shape, particularly for solidifying fuel for gas lighters. This eliminates the need for the conventional cooling filling method in which the product is cooled to -50°C to -60°C before filling, or the pressurized filling method in which the product is forcibly pressurized using nitrogen gas or the like. This has effects such as being able to be filled.

Claims (1)

[Claims] 1. Solidified liquefied petroleum gas obtained by adding a small amount of resin to a mixed solvent consisting of liquefied gas, a solid agent, a solvent compatible with liquefied petroleum gas, and an aprotic solvent. Composition. 2. The solidified liquefied petroleum gas composition according to claim 1, wherein the liquefied petroleum gas is liquefied propane (propane-propylene mixture) or liquefied butane (butane-butylene mixture). 3. The solidified liquefied petroleum gas composition according to claim 1, wherein the solvent that is compatible with liquefied petroleum gas is selected from the group consisting of acetone, oxo alcohol, and oleyl alcohol. 4. The solidified liquefied petroleum gas composition according to claim 1, wherein the resin is selected from the group consisting of rosin, ester gas, rosin derivatives, isoprene rubber, and polybutadiene.