Циклопентан

Химические свойства

Cyclopentane is a colourless flammable acyclic hydrocarbon liquid with a petrol-like smell. It is a widely used component in preparing products like analgesics, insecticides, sedatives, antitumor agents and also finds application in pharmaceutical industry.

Физические свойства

Colorless, mobile, flammable liquid with an odor resembling cyclohexane.

Использование

Cyclopentane is a petroleum product. Itis formed from high-temperature catalyticcracking of cyclohexane or by reduction ofcyclopentadiene. It occurs in petroleum etherfractions and in many commercial solvents.It is used as a solvent for paint, in extractionsof wax and fat, and in the shoe industry.

Методы производства

Cyclopentane occurs in petroleum ether fractions and is prepared by cracking cyclohexane in the presence of alumina at high temperature and pressure or by reduction of cyclopentadiene.

Определение

ChEBI: A cycloalkane that consists of five carbons each bonded with two hydrogens above and below the plane. The parent of the class of cyclopentanes.

Общее описание

A clear colorless liquid with a petroleum-like odor. Flash point of -35°F. Less dense than water and insoluble in water. Vapors are heavier than air.

Реакции воздуха и воды

Highly flammable. Insoluble in water.

Профиль реактивности

CYCLOPENTANE is incompatible with strong oxidizing agents such as chlorine, bromine, fluorine. .

Угроза здоровью

Cyclopentane is a low-acute toxicant. Itsexposure at high concentrations may producedepression of the central nervous system withsymptoms of excitability, loss of equilibrium,stupor, and coma. Respiratory failure may occur in rats from 30–60 minutes’ exposureto 100,000–120,000 ppm in air. It is anirritant to the upper respiratory tract, skin,and eyes. No information is available inthe literature on the chronic effects fromprolonged exposure to cyclopentane.

Пожароопасность

Behavior in Fire: Containers may explode.

Химическая реактивность

Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.

Профиль безопасности

Mildly toxic by ingestion and inhalation. High concentrations have narcotic action. A very dangerous fire hazard when exposed to heat or flame; can react with oxidizers. To fight fire, use foam, CO2, dry chemical. When heated to decomposition it emits acrid smoke and fumes.

Возможный контакт

Cyclopentane is used as a solvent.

Экологическая судьба

Biological. Cyclopentane may be oxidized by microbes to cyclopentanol, which may oxidize to cyclopentanone (Dugan, 1972).
Photolytic. The following rate constants were reported for the reaction of octane and OH radicals in the atmosphere: 3.7 x 10^-12 cm³/molecule?sec at 300 K (Hendry and Kenley, 1979); 5.40 x 10^-12 cm³/molecule?sec (Atkinson, 1979); 4.83 x 10^-12 cm³/molecule?sec at 298 K (DeMore and Bayes, 1999); 6.20 x 10^-12, 5.24 x 10^-12, and 4.43 x 10^-12 cm³/molecule?sec at 298, 299, and 300 K, respectively (Atkinson, 1985), 5.16 x 10^-12 cm³/molecule?sec at 298 K (Atkinson, 1990), and 5.02 x 10^-12 cm³/mol·sec at 295 K (Droege and Tilly, 1987).
Chemical/Physical. Cyclopentane will not hydrolyze because it has no hydrolyzable functional group. Complete combustion in air yields carbon dioxide and water.
At elevated temperatures, rupture of the ring occurs forming ethylene and presumably allene and hydrogen (Rice and Murphy, 1942).

Перевозки

UN1146 Cyclopentane, Hazard Class: 3; Labels: 3-Flammable liquid.

Методы очистки

Free it from cyclopentene by two passages through a column of carefully dried and degassed activated silica gel. It occurs in petroleum and is HIGHLY FLAMMABLE. [NMR: Christl Chem Ber 108 2781 1975, Whitesides et al. 41 2882 1976, Beilstein 5 III 10, 5 IV 4.]

Несовместимости

May form explosive mixture with air. May accumulate static electrical charges, and may cause ignition of its vapors. Contact with strong oxidizers may cause fire and explosion.

Утилизация отходов

Dissolve or mix the material with a combustible solvent and burn in a chemical incinera- tor equipped with an afterburner and scrubber. All federal, state, and local environmental regulations must be observed.