JPH07119693B2 - Quantitative analysis method of methyl tertiary-butyl ether in gasoline - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quantitative analysis method of methyl tertiary butyl ether (hereinafter referred to as MTBE) in gasoline.

[0002]

2. Description of the Related Art Currently, the petroleum industry is actively developing gasoline mixed with MTBE. this is,
When MTBE is mixed in gasoline, not only the octane number of gasoline becomes high, but also hydrocarbons (H
This is because C) and the amount of carbon monoxide (CO) are reduced, and the deterioration of the environment due to exhaust gas can be prevented.

[0003]

However, the MTB is already available.
It has been reported that bad gasoline containing a large amount of E is on the market. For this reason, at present, in laboratories equipped with equipment, accurate quantitative analysis by gas chromatography is performed to eliminate defective gasoline from the market.

However, although such a quantitative analysis method can accurately measure the amount of mixed MTBE, the measuring place is limited and the analysis operation becomes large. But I couldn't measure easily.

The present invention has been made in order to solve such a conventional problem, and MTBE in gasoline can be easily implemented by anyone at a store or on the road.
It aims at providing the quantitative analysis method of.

[0006]

The quantitative analysis method of MTBE in gasoline provided by the present invention is the following three methods.

(1) A quantitative analysis method including the following steps a to c (hereinafter referred to as a first quantitative analysis method). a. A process of adding to a gasoline a compound having a chromophore that is soluble in methyl tert-butyl ether but insoluble or hardly soluble in gasoline and its components. b. A step of adding gasoline to which a compound having a coloring group is added to any of an acid aqueous solution, an alkaline aqueous solution, a methanol solution of an acid, and a methanol solution of an alkali to develop a color. c. A step of comparing the developed color with a standard color or measuring the content of methyl tertiary butyryl ether by applying a color developing solution to a spectrophotometer.

(2) A quantitative analysis method in which a wetting agent for preventing evaporation of water in the solution is added to the acid aqueous solution, the alkaline aqueous solution, the acid methanol solution, and the alkali methanol solution in the first quantitative analysis method (hereinafter, referred to as The second quantitative analysis method).

(3) A quantitative analysis method including the following steps a to c (hereinafter referred to as a third quantitative analysis method). a. A process of adding to a gasoline a compound having a chromophore that is soluble in methyl tert-butyl ether but insoluble or hardly soluble in gasoline and its components. b. A step of adding color to a gasoline to which a compound having a color forming group has been added to any of oxides, hydroxides or carbonates of an alkali metal or an alkaline earth metal or a mixture thereof to develop a color. c. A step of comparing the developed color with a standard color or subjecting the developed powder to a spectrophotoelectric photometer to measure the content of methyl tertiary butyryl ether.

A pH indicator is typically known as the compound having a color forming group. Examples of the pH indicator include phthalein dyes such as phenolphthalein and thymol blue, sulfophthalein dyes such as phenol red and cresol red, carboxyazo dyes such as methyl red, pentamethoxy red and hexamethoxy red. Examples thereof include carbinol dyes.

Examples of the acid aqueous solution, the alkaline aqueous solution, the acid methanol solution, and the alkali methanol solution include:
Various standard buffer solutions, 0.1% sodium carbonate aqueous solution, 0.
1% sodium hydrogen carbonate solution, 0.1% sodium hydroxide solution, 0.1% hydrochloric acid solution, 0.1% sulfuric acid solution, 0.1% acetic acid solution, 0.1% oxalic acid solution,
Examples thereof include 0.1% tartaric acid aqueous solution and respective methanol solutions. Further, it is also possible to use an alkali metal such as potassium or lithium in place of the above sodium.

Examples of the wetting agent include polyhydric alcohols such as glycerin, and ether compounds of glycols such as ethylene glycol and propylene glycol.

Examples of powders of oxides, hydroxides or carbonates of alkali metals or alkaline earth metals include calcium oxide, barium oxide, strontium oxide, calcium hydroxide, barium hydroxide, strontium hydroxide and sodium carbonate. , Potassium carbonate, lithium carbonate, calcium carbonate, barium carbonate, strontium carbonate and the like.

[0014]

When a compound having a color-forming group is added to gasoline, it dissolves in MTBE, but it is insoluble in other components or a small amount even if dissolved. Therefore, when gasoline to which a compound having a color forming group is added is added to any one of an acid aqueous solution, an alkaline aqueous solution, a methanol solution of an acid, and a methanol solution of an alkali (first quantitative analysis method), a compound having a color forming group is added. When the added gasoline is added to any of oxides, hydroxides or carbonates of alkali metal or alkaline earth metal or a mixture thereof (3rd
Quantitative analysis method), it can be seen that MTBE is present if color is developed, and MTBE is not present if color is not developed. If present, the amount of MTBE incorporated can be determined by comparing the developed color with a standard color or by subjecting the developed aqueous solution to a spectrophotometer.

In the second quantitative analysis method, when the test paper or the like is impregnated with an acid aqueous solution, an alkaline aqueous solution or the like,
If a wetting agent is added to the solution in advance, it is possible to prevent evaporation of water in the solution and prevent the solution from being dried.

[0016]

Embodiments of the present invention will be described below. Examples 1 to 3 are examples of the first quantitative analysis method, Example 4 is an example of the second quantitative analysis method, and Example 5 is an example of the third quantitative analysis method. Each of the examples was carried out at room temperature.

EXAMPLE 1 Phenolphthalein 0.1 was added to each of 10 50 ml Erlenmeyer flasks.
g, MTBE content is 0%,
5%, 10%, 12%, 15%, 20%, 40%, 60
%, 80%, 100% (MTBE itself) of gasoline 5ml respectively, each with a touch mixer 3
After stirring for 1 minute, insoluble phenolphthalein was removed with a membrane filter (which can also be performed by a centrifugal precipitation method), and 1 ml of each was added to each test tube containing 5 ml of 0.1% sodium carbonate aqueous solution in advance. After stirring and reacting with a touch mixer for 1 minute, color was developed depending on the content of MTBE. The color of the lower layer was 0.
When 1% sodium carbonate aqueous solution was collected, MTBE
A red colored liquid having a concentration difference depending on the content of was obtained in series.

The color of each of the obtained colored liquids was visually compared with the standard color prepared in advance for each known content of MTBE by the same operation as described above, and the MTBE content of each gasoline was found. I was able to measure accurately.

On the other hand, when the same colored liquid was measured with a spectrophotometer, the transmittance curve shown in FIG. 1 was obtained. Further, this solution was diluted 50 times with a 0.1% sodium carbonate aqueous solution and then measured with a spectrophotophotometer, and the transmittance curve shown in FIG. 2 was obtained.

(Example 2) 0.1 g of thymol blue was placed in each of 10 50 ml Erlenmeyer flasks, and MTBE contents were 0%, 5%, respectively.
10%, 12%, 15%, 20%, 40%, 60%, 8
Add 5 ml of 0% and 100% (MTBE itself) gasoline, stir each for 3 minutes with a touch mixer, remove insoluble thymol blue with a membrane filter, and remove 1 ml of each with 0.1% carbonic acid in advance. When 5 ml of an aqueous solution of sodium was added to each test tube and the mixture was stirred and reacted for 1 minute with a touch mixer, color was developed depending on the content of MTBE. When the colored 0.1% sodium carbonate aqueous solution in the lower layer was collected, MT
A blue colored liquid having a concentration difference depending on the BE content was obtained in series.

The color of each of the obtained colored liquids was visually compared with the standard color prepared in advance for each known content of MTBE by the same operation as described above, and the MTBE content of each gasoline was found. I was able to measure accurately.

On the other hand, when the same colored liquid was measured with a spectrophotometer, the transmittance curve shown in FIG. 3 was obtained. Further, when this solution was diluted 50 times with a 0.1% sodium carbonate aqueous solution and then measured with a spectrophotometer, the transmittance curve shown in FIG. 4 was obtained.

Example 3 0.1 g of thymol blue was placed in each of 10 50 ml Erlenmeyer flasks, and MTBE contents were 0% and 5%, respectively.
10%, 12%, 15%, 20%, 40%, 60%, 8
Add 5 ml of 0% and 100% (MTBE itself) gasoline, stir each for 3 minutes with a touch mixer, remove insoluble thymol blue with a membrane filter, and remove 1 ml of each with 0.1% hydrochloric acid in advance. When 5 ml of a methanol solution was added to each test tube and the mixture was stirred and reacted for 1 minute with a touch mixer, a color-developed solution was obtained depending on the MTBE content. This colored solution was a red colored liquid having a concentration difference depending on the MTBE content, and was obtained in series.

When each of the obtained colored liquids was measured by a spectrophotometer, the transmittance curve shown in FIG. 5 was obtained. Further, this solution was diluted 50 times with a 0.1% hydrochloric acid methanol solution and then measured with a spectrophotometer.
The transmittance curve shown in was obtained.

Example 4 0.1 g of thymol blue was placed in each of 10 50 ml Erlenmeyer flasks, and MTBE contents were 0% and 5%, respectively.
10%, 12%, 15%, 20%, 40%, 60%, 8
5 ml of 0% and 100% (MTBE itself) gasoline was added, each was stirred with a touch mixer for 3 minutes, and insoluble thymol blue was removed with a membrane filter to obtain gasoline added with thymol blue.

Then, 1 ml of each gasoline was dropped onto a test paper which had been previously impregnated with a 0.1% sodium carbonate aqueous solution to which glycerin was added as a wetting agent. As a result, a color was developed in accordance with the MTBE content. .

The color of each of the obtained colored test papers was visually compared with the standard color prepared in advance for each known content of MTBE by the same operation as described above. Was able to be measured accurately.

Example 5 Phenolphthalein 0.1 was added to each of 10 50 ml Erlenmeyer flasks.
g, the MTBE content in each of these is 0%,
5%, 10%, 12%, 15%, 20%, 40%, 60
%, 80%, 100% (MTBE itself) of gasoline 5ml respectively, each with a touch mixer 3
After stirring for a minute, the insoluble phenolphthalein was removed by a membrane filter (which can also be carried out by a centrifugal precipitation method), and 1 ml of each was added to the calcium hydroxide powder previously placed in a perforated dish. Color was developed depending on the content.

The color of each of the obtained colored powders was visually compared with the standard color prepared in advance for each known content of MTBE by the same operation as described above, and the MTBE content of each gasoline was determined. I was able to measure accurately.

[0030]

As described above, according to the present invention, a coloring group is added to gasoline to dissolve only MTBE therein, and the solubility at that time is detected as a color with a coloring aqueous solution or coloring powder, Since it is possible to measure the amount of MTBE mixed in by comparing this with a standard color or by using a spectrophotometer, a simple instrument such as a compound having a chromophore, a coloring aqueous solution or a coloring powder and a test tube or a flask can be used. If so, anyone can easily measure the amount of MTBE mixed in gasoline, whether at the store or on the street.

[Brief description of drawings]

FIG. 1 is a graph showing a transmittance curve of a colored liquid in Example 1.

FIG. 2 is a graph showing a transmittance curve when the coloring liquid in Example 1 was diluted 50 times.

FIG. 3 is a graph showing a transmittance curve of a colored liquid in Example 2.

FIG. 4 is a graph showing a transmittance curve when the coloring liquid in Example 2 was diluted 50 times.

5 is a graph showing a transmittance curve of a colored liquid in Example 3. FIG.

FIG. 6 is a graph showing a transmittance curve when the coloring liquid in Example 3 was diluted 50 times.

Claims (3)

[Claims] 1. A method for quantitative analysis of methyl tertiary butyryl ether in gasoline, which comprises the following steps a to c: a. A process of adding to a gasoline a compound having a chromophore that is soluble in methyl tert-butyl ether but insoluble or hardly soluble in gasoline and its components. b. A step of adding gasoline to which a compound having a coloring group is added to any of an acid aqueous solution, an alkaline aqueous solution, a methanol solution of an acid, and a methanol solution of an alkali to develop a color. c. A step of comparing the developed color with a standard color or measuring the content of methyl tertiary butyryl ether by applying a color developing solution to a spectrophotometer. 2. Methyl in gasoline according to claim 1, wherein a wetting agent for preventing evaporation of water in the solution is added to the aqueous acid solution, the aqueous alkali solution, the acid methanol solution, and the alkaline methanol solution. -Quantitative analysis method of tertiary butyrether. 3. A method for quantitative analysis of methyl tertiary butyryl ether in gasoline, which comprises the following steps a to c. a. A process of adding to a gasoline a compound having a chromophore that is soluble in methyl tert-butyl ether but insoluble or hardly soluble in gasoline and its components. b. A step of adding color to a gasoline to which a compound having a color forming group has been added to any of oxides, hydroxides or carbonates of an alkali metal or an alkaline earth metal or a mixture thereof to develop a color. c. A step of comparing the developed color with a standard color or subjecting the developed powder to a spectrophotoelectric photometer to measure the content of methyl tertiary butyryl ether.