JPS63207885A - Heat transfer medium oil - Google Patents

Abstract

PURPOSE:To obtain a novel heat transfer medium oil, useful for heating devices for chemical reaction, reboiler for distillation column, heating devices, etc., having excellent heat stability, odorless properties and biodegradation properties, comprising a specific diarylbutane (mixture). CONSTITUTION:The heat transfer medium oil comprising one or more diarylbutanes shown by the formula (R<1>-R<5> are H, phenyl, tolyl or ethylphenyl with the proviso that sum of number of total substitutions except H among R<1>-R<5> is 2 and at least one of the substitutions is phenyl). The diarylbutane, for example, is obtained by reacting (ethyl)benzene or toluene with 1- phenyl-2-butene in the presence of an aluminum halide catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel heat transfer oil, and more specifically to a thermally stable, odorless, and bioactive heat transfer oil composed of one or more diarylbutanes having a specific structure. Related to heat transfer oil with excellent degradability.

Heat transfer oil is used in an extremely wide range of fields as a heat transfer medium for heating chemical reaction equipment, heating distillation column reboilers, heating appliances for heating, etc.

By the way, the above-mentioned heat transfer oil is required to satisfy the following requirements.

(a) It has a high boiling point, is nonvolatile, and has low flammability.

(b) Good low-temperature fluidity.

(C) Excellent thermal stability.

(d) Not corrosive to metal materials.

(e) It has little odor.

(f) It is non-toxic and has excellent biodegradability.

(()) It should be inexpensive.

Conventionally, such heat transfer oils include refined mineral oils with added antioxidants, phenyl ethers, aryl alkanes, or alkyldiphenyls or alkylnaphthalenes having methyl, ethyl, or propyl groups. It is being However, all of these heat transfer oils have a problem that they cannot be used for a long time because they are inferior in heat resistance and suffer from oxidative deterioration and carbon generation due to thermal decomposition.

Furthermore, various proposals have been made regarding the use of diaryl alkanes as heat transfer oils. For example, 1,2-diarylethane is disclosed in JP-A-48-18270, and JP-A-61-196 discloses 1,2-diarylethane.
85 discloses 2,2-phenylnaphthylpropane, and JP-A-48-16684 discloses 2,2-phenylnaphthylpropane.
No. 50-4048, No. 50-57082, and No. 57-115481 disclose 1,1-diarylethane and the like.

However, although the heat transfer oil disclosed in the above-mentioned publication has favorable conditions as a heat transfer oil such as low viscosity, low melting point, and high boiling point, it has poor thermal stability, strong odor, In addition, there were other problems such as poor biodegradability.

In order to solve these problems, the present inventors conducted research on various diarylalkanes, and found that they have excellent thermal stability compared to the above-mentioned diarylethanes and diarylpropanes. The present invention has been completed by discovering a heat transfer oil made of one or more diarylbutanes that has low odor and excellent biodegradability.

The present invention is an attempt to solve the problems associated with the prior art as described above, and it satisfies the requirements for a heat transfer oil, has particularly excellent thermal stability, and has no odor. The purpose of the present invention is to provide a heat transfer oil that is low in biodegradability and has excellent biodegradability.

Context Vehicle Equipment The heat transfer oil according to the present invention is characterized by comprising one or more diarylbutanes represented by the following general formula.

R1R3R4R5 H-C-C-C-(,-)(2HHH In the formula, R1, R2, R3, R4 and R5 are each a hydrogen atom, a phenyl group, a tolyl group or an ethylphenyl group, and R1, R2, R3, Among R4 and R5, the total number of substituents other than hydrogen is 2, and at least one of them is a phenyl group.

Le blood mastication device stray dwarf The heat transfer oil according to the present invention will be specifically explained below.

The heat transfer oil according to the present invention is composed of one or more diarylbutanes, and specific examples of diarylbutanes are as follows.

1.1-diphenylbutane, 1,2-diphenylbutane, 1.3-diphenylbutane, 1,4-diphenylbutane, 1-phenyl-1-tolylbutane, 1-phenyl-
2-tolylbutane, 1-phenyl-3-tolylbutane,
1-phenyl-4-tolylbutane, 1-tolyl-2-phenylbutane, 1-tolyl-3-phenylbutane, 2-
Tolyl-3-phenylbutane, 1-phenyl-1-ethylphenylbutane, 1-phenyl-2-ethylphenylbutane, 1-phenyl-3-ethylphenylbutane, 1-
Phenyl-4-ethylphenylbutane, 1-ethylphenyl-2-phenylbutane, 1-ethylphenyl-3-
Phenylbutane, 2-ethylphenyl-3-phenylbutane.

The diarylbutanes constituting the heat transfer oil may be used alone or as a mixture.

Diarylbutane according to the present invention can be produced, for example, by reacting benzene, toluene or ethylbenzene with 1-phenyl-2-butene in the presence of an aluminum halide catalyst. It can also be produced by reacting benzene with 1-tolyl-2-butene or 1-ethylphenyl-2-butene.

Specifically, the aluminum halide used as a catalyst includes AI CI, AI Br3, AI
I, AI F3, etc. are used, but among these, A
lCl3 is preferred.

Aluminum halides may be used by themselves, but they can also be used as organic nitro compounds, esters, ethers, ketones,
It can also be used in a complex with methylbenzene or the like.

Alternatively, it can be prepared by condensation of benzene or/and toluene or/and ethylbenzene with n-butyraldehyde in the presence of sulfuric acid, which is a known production process. The medium oil has excellent thermal stability, low odor, and excellent biodegradability.

In addition, the heat transfer oil made of one or more diarylbutanes of the present invention has excellent properties such as thermal stability, odorlessness, and biodegradability, in addition to the various properties required of ordinary heat transfer oils even when used as is. However, if necessary, known additives such as antioxidants, antifoam agents, cleaning dispersants, rust inhibitors, or pour point depressants can be added.

Furthermore, the heat transfer oil according to the present invention may be mixed with a known heat transfer oil such as a diphenyl ether and diphenyl mixed system such as alkylnaphthalene, alkyldiphenyl, dowsum, and marosam.

The heat transfer oil according to the present invention has excellent thermal stability, low odor, and excellent biodegradability.

Moreover, it has excellent properties such as a high boiling point, good fluidity, and low viscosity.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Note that % in the examples indicates weight %.

10 mol of benzene and 0.1 mol of anhydrous aluminum chloride were placed in a 482 D glass reactor equipped with a mechanical stirrer, and the internal temperature was maintained at 10° C. while stirring.

A mixed solution of 0.5 mol of 1-phenyl-2-butene and 2 mol of benzene was continuously added dropwise thereto over 4 hours to cause a reaction. After the dropwise addition of the mixed solution was completed, the temperature was maintained at 10° C. for 20 minutes while stirring. Thereafter, stirring was stopped, and the reaction product was separated and recovered, washed and neutralized with an aqueous solution of caustic soda, dried over sodium sulfate, and then distilled under reduced pressure to obtain 368 mmol of colorless and transparent diphenylbutane. The isomer composition of the obtained diphenylbutane was 24% 1,1, 25% 1,2, and 51% 1.3. 1-phenyl-
The conversion rate of 2-butene was 100%, and the conversion rate of 1-phenyl-
The yield based on 2-butene was 73.6%.

In order to investigate the general properties of the heat transfer oil thus obtained, physical properties such as specific gravity, boiling point, pour point, and viscosity were measured. The results are shown in Table 1.

Furthermore, an autoclave test was conducted using the obtained heat transfer oil to examine its thermal stability. The test conditions were a temperature of 340°C;
The nitrogen pressure was 15 g/-, and the pressure increase after 300 hours was measured. The results are shown in Table 1.

In addition, in order to perform an odor test on the obtained heat transfer oil, 30 testers exposed the heat transfer oil to determine the odor, and the results are shown in Table 1.

In order to examine the biodegradability of the obtained heat transfer oil, the following biodegradability test was conducted. 100 ml of basic culture medium was placed in a shaking flask with a capacity of 500 ml, and heat medium oil was added to this basic culture medium so that the amount was 2001) l) m. Next, activated sludge was added so that the suspended solids concentration was 100 pI)m. The flask was plugged with cotton and cultured for 2 weeks while being maintained at 25±1°C in a shaking incubator (manufactured by Mitamura Riken). After culturing, heat transfer oil was extracted from the shaking flask, and the biodegradation rate was determined using a gas chromatograph. The results are shown in Table 1.

In Example 1, phenyltolylbutane 3 was prepared in the same manner as in Example 1, except that toluene was used instead of benzene.
86 mmol was obtained. This isomer composition is 1,1 monolithic 13
%, 1.2 unit was 45%, and 1,3 unit was 42%. 1
The conversion rate of -phenyl-2-butene was 100%, and the yield based on the same standard was 77.2%.

Measurement of physical properties of the obtained heat transfer oil in the same manner as in Example 1,
A thermal stability test, an odor test and a biodegradability test were conducted. The results are shown in Table 1.

395 mmol of phenylethylphenylbutane was obtained in the same manner as in Example 1, except that ethylbenzene was used instead of benzene. The isomer composition is 6% of 1.1, 35% of 1,2, and 59% of 1.3.
Met. The conversion rate of 1-phenyl-2-butene is 100
%, and the yield based on the same standard was 79.0%.

Measurement of physical properties of the obtained heat transfer oil in the same manner as in Example 1,
A thermal stability test, an odor test and a biodegradability test were conducted. The results are shown in Table 1.

1- Put 2.0 mol of 94 wt% sulfuric acid into a 1 g glass reactor equipped with a stirrer, and stir a mixture of 0.4 mol of benzene and 0.07 mol of n-butyraldehyde at 15°C for 3 minutes. After continuously adding the contents little by little, the temperature of the contents was cooled and maintained at -10°C, and without stirring, a mixture of 0.63 mol of n-butyraldehyde and 3.60 mol of benzene was added over 4 hours. The mixture was continuously added dropwise little by little to react. During this time, the concentration of n-butyraldehyde in the reaction system was 0.
It was 5% by weight or less. After the dropwise addition was completed, stirring was continued for 30 minutes at -10°C. After that, stirring is stopped, the reactor is stopped, and the reaction product is separated and collected, washed and neutralized with an aqueous sodium carbonate solution, dried over magnesium chloride, and then distilled under reduced pressure to yield 1,1-diphenylbutane. 90% (n-
butyraldehyde standard).

Measurement of physical properties of the obtained heat transfer oil in the same manner as in Example 1,
A thermal stability test, an odor test and a biodegradability test were conducted. The results are shown in Table 1.

Comparison 1 Using 1-phenyl-1-(3,4-dimethylphenyl)ethane as the heat transfer oil, physical property measurements, thermal stability tests, odor tests, and biodegradation tests were conducted in the same manner as in Example 1. Ta. The results are shown in Table 1 in comparison with Examples.

Physical property measurements, thermal stability tests, odor tests, and biodegradation tests were conducted in the same manner as in Example 1 using diisopropylnaphthalene as the heat transfer oil. The results are shown in Table 1 in comparison with Examples.

From Table 1, it can be seen that the heat transfer oil according to the present invention has excellent thermal stability, low odor, and excellent biodegradability.

Claims (4)

[Claims] (1) 1 of diarylbutane represented by the general formula below
A heat transfer oil consisting of a species or two or more species. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R^1, R^2, R^3, R^4 and R^5
are hydrogen atoms, phenyl groups, tolyl groups, or ethylphenyl groups, respectively, and R^1, R^2, R^3, R^4
and R^5, the total number of substituents other than hydrogen is 2, and at least one of them is a phenyl group. ] (2) The heat transfer oil according to claim 1, wherein the diarylbutane is diphenylbutane. (3) The heat transfer oil according to claim 1, wherein the diarylbutane is phenyltolylbutane. (4) The heat transfer oil according to claim 1, wherein the diarylbutane is phenylethyl phenylbutane.