n-Decane

Химические свойства

Decane, C10H22, is a flammable liquid with specific gravity 0.73. Decane is a constituent in the paraffin fraction of crude oil and natural gas. It is released to the environment via the manufacture, use, and disposal of many products associated with the petroleum, gasoline, and plastics industries.

Физические свойства

Clear, colorless liquid. Reported odor threshold concentrations were 11.3 mg/m³ by Laffort and Dravnieks (1973) and 620 ppb_v by Nagata and Takeuchi (1990).

Использование

Decane is obtained mainly from the refining of petroleum. It is a component of engine fuel and is used in organic synthesis, as a solvent, as a standardized hydrocarbon, and in jet fuel research.

Реакции

The Combustion Reaction of Decane is as follows:
Like all hydrocarbons, decane undergoes hydrocarbon combustion when used as a fuel. The balanced chemical equation for the complete combustion of decane is: 
2 C₁₀H₂₂ + 31 O₂ → 20 CO₂ + 22 H₂O + Heat Energy (Enthalpy) 
The hydrocarbon combustion reaction releases heat energy and is an example of an exothermic reaction. The reaction also has a negative enthalpy change (ΔH) value.

Общее описание

A colorless liquid. Flash point 115°F. Less dense than water and insoluble in water. Vapors heavier than air. In high concentrations its vapors may be narcotic. Used as a solvent and to make other chemicals.

Реакции воздуха и воды

Flammable. Insoluble in water.

Профиль реактивности

DECANE is incompatible with oxidizing agents.

Угроза здоровью

Contact with eyes may produce mild irritation. Contact with skin may cause defatting, redness, scaling, and hair loss. Ingestion may cause diarrhea, slight central nervous system depression, difficulty in breathing and fatigue. Inhalation of high concentrations may cause rapid breathing, fatigue, headache, dizziness, and other CNS effects.

Пожароопасность

Special Hazards of Combustion Products: May produce toxic fumes, including carbon monoxide.

Профиль безопасности

Questionable carcinogen with experimental tumorigenic data. A simple asphyxiant. Narcotic in high concentrations, Flammable liquid when exposed to heat or flame. Can react with oxidizing materials. Moderately explosive in its vapor form. To fight fire, use foam, CO2, dry chemical. Emitted from modern buildtng materials (CENEAR 69,22,91). See also ARGON for discussion of asphyxiants.

Канцерогенность

Mice treated with decane developed tumors on the backs, after exposure to ultraviolet radiation at wavelengths longer than 350 nm, generally considered noncarcinogenic. A series of 21 tobacco smoke components and related compounds were applied to mouse skin (50 female ICR/Ha Swiss mice/group) three times weekly with 5 mug/application of benzo[a]pyrene (B[a]P). The test compounds were of five classes: aliphatic hydrocarbons, aromatic hydrocarbons, phenols, and longchain acids and alcohols. Decane was among the compounds that enhanced remarkably the carcinogenicity of B[a]P. and also acted as tumor promoter in two-stage carcinogenesis.

Экологическая судьба

Biological. Decane may biodegrade in two ways. The first is the formation of decyl hydroperoxide, which decomposes to 1-decanol, followed by oxidation to decanoic acid. The other pathway involves dehydrogenation to 1-decene, which may react with water giving 1-decanol (Dugan, 1972). Microorganisms can oxidize alkanes under aerobic conditions (Singer and Finnerty, 1984). The most common degradative pathway involves the oxidation of the terminal methyl group forming the corresponding alcohol (1-decanol). The alcohol may undergo a series of dehydrogenation steps, forming decanal, followed by oxidation forming decanoic acid. The fatty acid may then be metabolized by β-oxidation to form the mineralization products, carbon dioxide and water (Singer and Finnerty, 1984). Hou (1982) reported 1-decanol and 1,10-decanediol as degradation products by the microorganism Corynebacterium.
Photolytic. A photooxidation reaction rate constant of 1.16 x 10^-11 cm³/molecule?sec was reported for the reaction of decane with OH in the atmosphere (Atkinson, 1990).
Chemical/Physical. Complete combustion in air yields carbon dioxide and water vapor. Decane will not hydrolyze because it has no hydrolyzable functional group.

Методы очистки

It can be purified by shaking with conc H2SO4, washing with water, aqueous NaHCO3, and more water, then drying with MgSO4, refluxing with Na and distilling. Also purify through a column of silica gel or alumina. It has been purified by azeotropic distillation with 2-butoxyethanol, the alcohol being washed out of the distillate, using water, the decane is next dried and redistilled. It can be stored with NaH. Further purification can be achieved by preparative gas chromatography on a column packed with 30% SE-30 (General Electric methyl-silicone rubber) on 42/60 Chromosorb P at 150o and 40psig, using helium [Chu J Chem Phys 41 226 1964]. It is soluble in EtOH and Et2O. [Beilstein 1 IV 484.]