Cyclohexane flash point

Compounds with low flash points (below room temperature). Examples are acetaldehyde, acetone, acetonitrile, benzene, carbon disulfide, cyclohexane, diethyl ether, ethyl acetate and -hexane. 

Cyclohexane (hexahydrobenzene, melting point 6.5°C, boiling point 81°C, density 0.7791, flash point -20°C) can be quantitatively produced from benzene by hydrogenation over either a nickel or a platinum catalyst at 210°C and 350 to 500 psi hydrogen (Fig. 1). 

A flammable chemical substance is a solid, liquid, vapor, or gas that ignites easily and burns rapidly in air. Many of the flammable chemicals used in laboratories are flammable liquids and organic solvents. The vapors of these chemical substances form ignitable mixtures with air. Based on the flash points of these chemicals, classifications are made. The flash point of a chemical substance is defined as the lowest temperature at which a fuel-air mixture present above the surface of a liquid will ignite, if an ignition source is present. The common flammable chemical substances include, but are not restricted to, acetone, benzene, cyclohexane, ethanol, ethyl acetate, ethyl ether, gasoline, hexane, isopropyl alcohol, methanol, propanol, tetrahydro-furan and toluene, and xylene. 

ISOPROPYL CYCLOHEXANE (696-29-7) CgHig Forms explosive mixture with air (flash point 96°F/36°C also reported at 143°F/62°C autoignition temp 540°F/282°C Fire Rating 3). Incompatible with aldehydes, strong oxidizers, nitric acid. Reacts with sulfuric acid to form an explosive. Heat causes explosive decomposition. acidic materials increase thermal sensitivity. On small fires, use dry chemical powder (such as Purple-K-Powder), foam, or CO extinguishers. ISOPROPYL 2,4-DICHLORO-PHENOXY ACETATE (94-11-1)... 

CYCLOHEXANE (110-82-7) Forms explosive mixture with air (flash point —4°F/—20°C). Violent reaction with strong oxidizers, nitrogen tetroxide. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

HEXACHLOR-CYCLOHEXANE (58-89-9) Noncombustible however, the commercial product may be dissolved in a flammable solvent. The flash point will depend on the solvent used. If this material comes into contact with oxidizers, fire and explosions may result. Incompatible with aluminum, potassium, sodium. Corrosive to metals. 

HYDROXYIMINO)CYCLOHEXANE (100-64-1) Combustible solid (flash point 217°F/103°C). May form unstable peroxides, unless inhibited. Reacts with strong oxidizers, strong acids in the presence of elevated temperatures above 300°F/149°C, the reaction may be explosive. 

METHYLCYCLOHEXANONE or o-METHYLCYCLOHEXANONE or 1-METHYL-CYCLOHEXAN-2-ONE (583-60-8) Forms explosive mixture with air (flash point 118°F/48°C cc). Violent reaction with oxidizers, aldehydes, nitric acid, perchloric acid. A variety of unstable peroxides may be formed from the reaction with hydrogen peroxide. Incompatible with aliphatic amines, strong bases, hydrogen peroxide, perchloric acid. Attacks some plastics, rubber, and coatings. 

F]), cyclohexane (245 C [473°F]), re-pentane (260°C [500°F]), ethanol (365°C [689°F]), methanol (385 C [725 F]), and isopropanol (399°C [750 F]). Table IX.l provides flash point and autoignition temperature data for some common flammable compounds. The flammability data for these compounds, as well as those of other flammable and combustible substances, are presented throughout this book. 

The process fluid. Cyclohexane (CgHi2, MW 84) is a colorless liquid similar in some of its properties to gasoline (flash point 20°C, auto-ignition temperature (AIT) 245°C). The fluid has a normal boiling point of 80°C and a saturation pressure, p i, at 150°C of 0.55 MPa. When the liquid was saturated with nitrogen, or air as when oxidation was occurring in the reactor stream, the pressure was 0.96 MPa. Under these conditions the liquid was 99.8% CsHi2 and 0.2% Nj or air the vapor would have consisted of 82.6% C Hij and 17.4% Nj... 

Fig. 12. Transient IR difference spectra showing changes in absorbance (a) 5 / seconds, (b) 25 seconds, and (c) 1.25 mseconds after the UV flash photolysis of [CpFe(CO)2]2 in cyclohexane solution under 1 atm pressure of CO. Bands pointing upward represent an increase in absorbance (i.e., formation of a compound) and those pointing downward a decrease [i.e., depletion of starting material, (A)]. The bands are assigned as follows A, [CpFe(CO)2]2 B, CpFe(CO)2 and C, CpFe(p.-CO)3Fe(Cp). Points marked were recorded with a 12CO laser and those marked + with a 13CO laser. [Reproduced with permission from Moore et al. (61).]...

In principle, the application of time-resolved techniques permits identification of intermediates by monitoring their progress to the stable products of reaction. In 1973, Lehman and Berry [25] reported the first application of time-resolved photochemical methods to the study of aryl azides. Using conventional flash photolysis, they irradiated 2-azidobiphenyl in cyclohexane solution. Time-resolved absorption spectroscopy revealed an intermediate assigned as the triplet nitrene primarily on the basis of the similarity of its spectrum to that measured by Reiser [18] in low-temperature experiments. Lehman [25] monitored the rate of carbazole formation and found it to occur by a kinetically first-order process with a lifetime of 460 /is at room temperature. These findings led them to conclude that photolysis of 2-azidobiphenyl at room temperature leads rapidly to the triplet nitrene, and that this species is the precursor to carbazole [25], However, this point of view clearly is at odds with Swenton s triplet sensitization experiments [23],... 

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