Pyrophoric liquids

CAS 1191-15-7. [(CH3)2CHCH2]2A1H. Properties Colorless liquid. Pyrophoric. Fp -80C, bulk d 0.798, bp 105C (0.2 mm Hg). Miscible with hydrocarbon solvents dilute solutions nonpyro-phoric. 

The American National Standards Institute (ANSI) has established a voluntary standard for chemical labeling, ANSI Z129.11994, Hazardous Industrial Chemical Precautionary Labeling, which includes readily identifiable symbols for poisons, corrosives, flammables, and explosives. Irritants, combustible liquids, pyrophoric chemicals, oxidizers, sensitizers, physiologically inert vapors, gases and other hazardous materials are also addressed. 

Colorless to yellow, oily liquid. Pyrophoric in air burns to FejOj. Dec by light to Fe/cO), and CO. mp —20". bp 103, dj° 1.46-1.52 rtg 1.453. Critical temp 285-288 critical pressure 29.6 atm. Flash pi —15. Heat capacity at constant pressure (14 ) 56.9 cal/mole/ C. Latent heat of fusion 3161 cal/mol latent heat of vaporization 9.6kcal/-mole. Heat of combustion —386.9 kcal/mole heat of formation [Fe(CO),0iq)] —182.6 kcal/mole. Practically insol in water readily sol in most organic solvents including ether, benzene, petr ether, acetone, ethyl acetate, carbon tetrachloride, carbon disulfide slightly sol in alcohol practically insol in liquid ammonia. Protect from light and air, LDM in mice, rats 2.19, 0.91 mg/1 inhalation, exposure for 30 min. (Sunderman). 

Any liquid pyrophoric material poses a special hazard to an aircraft in flight, and severe limitations apply to such materials. Where a radioactive substance which has the subsidiary hazard of pyrophoricity is also a liquid, there is a greater probability of a spiU occurring, and it is therefore absolutely forbidden to transport such a substance by air. 

Self-reactive substances and mixtures Pyrophoric liquids Pyrophoric solids... 

Ignition element for lighter, containing pyrophoric liquid Inositol hexanitrate (dry)... 

Lighters (cigarettes) containing pyrophoric liquid Lighters (cigarettes) with lighter fluids... 

Location and General Requirements. Locations shall be classified depending on the properties of the flammable vapors, liquids or gases or combustible dusts or fibers that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Where pyrophoric materials are the only materials used or handled, these locations shall not be classified. 

Other media in which titanium is subject to pyrophoricity are anhydrous liquid or gaseous chlorine , liquid bromine, hot gaseous fluorine, or oxygen-enriched atmospheres at moderately low pressures. 

The catalyst is washed thoroughly with 100 ml. of water and with 200 ml. of absolute methanol to remove all traces of water, after which it is transferred to the flask under nitrogen with a minimal amount of absolute methanol. To be effective the catalyst must be pyrophoric, and extreme care must be taken during this operation to prevent ignition of the methanol or ammonia. The catalyst must not be allowed to become dry or to collect on the wall of the flask above the surface of the liquid ammonia. 

Airborne particulate matter may comprise liquid (aerosols, mists or fogs) or solids (dust, fumes). Refer to Figure 5.2. Some causes of dust and aerosol formation are listed in Table 4.3. In either case dispersion, by spraying or fragmentation, will result in a considerable increase in the surface area of the chemical. This increases the reactivity, e.g. to render some chemicals pyrophoric, explosive or prone to spontaneous combustion it also increases the ease of entry into the body. The behaviour of an airborne particle depends upon its size (e.g. equivalent diameter), shape and density. The effect of particle diameter on terminal settling velocity is shown in Table 4.4. As a result ... 

Safety. The MR is much safer than the MASR. (1) The reaction zone contains a much smaller amount of the reaction mixture (hazardous material), which always enhances process safety. (2) In case of pump failure, the reaction automatically stops since the liquid falls down from the reaction zone. (3) There is no need to filter the monolithic catalyst after the reaction has been completed. Filtration of the fine catalysts particles used in slurry reactors is a troublesome and time-consuming operation. Moreover, metallic catalysts used in fine chemicals manufacture are pyrophoric, which makes this operation risky. In a slurry reactor there is a risk of thermal runaways. (4) If the cooling capacity is insufficient (e.g. by a mechanical failure) a temperature increase can lead to an increase in reaction, and thus heat generation rate. 

Not generally pyrophoric, unless dropped on vermiculite, the complex decomposes slowly in the liquid phase to generate considerable pressures of hydrogen. It appears much more stable in the vapour phase. 

Specially bottled methyl bromide, in an aluminium cylinder under nitrogen pressure, disgorged a black sludge when liquid was discharged. Inversion and venting, to blow free the line, gave a burst of flame from the vent. It is presumed that corrosion of the cylinder produced pyrophoric aluminium alkyls. 

It reacts similarly to the disodium salt [1], If heated to 150°C, it decomposes extensively, evolving gas which ignites in air owing to presence of pyrophoric carbon. The residual carbon is also highly reactive [2], The dry powder (lfom solution in liquid ammonia) may ignite if exposed to air as an extended layer, e.g. on filter paper [3],... 

At ambient temperature, ammonia gas reacts exothermally with calcium, but if warmed the latter becomes incandescent [1], The metal dissolves unchanged in liquid ammonia, but if the latter evaporates, the finely divided metal is pyrophoric [2],... 

It reacts vigorously with air and/or water (vapour or liquid) and adequate handling precautions are necessary [1], The finely divided powder is pyrophoric in air [2],... 

Accidental admixture of oxygen gas with unstabilised liquid tetrafluoroethylene produced a polymeric peroxide which was powerfully explosive, and sensitive to heat, impact or friction [1], Removal of oxygen by treatment with pyrophoric copper to prevent explosion of tetrafluoroethylene has been claimed [2],... 

Finely divided (pyrophoric) chromium incandesces in sulfur dioxide [1], while pyrophoric manganese bums brilliantly on heating in the gas [2], Molten sodium reacts violently with the dry gas or liquid, while the moist gas reacts as vigorously as water with cold sodium [3],... 

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