Sulfur dioxide fire exposure

Composite materials must survive in the environment to which they are subjected at least as well as the conventional materials they replace. Some of the harmful environments encountered include exposure to humidity, water immersion, salt spray, jet fuel, hydraulic fluid, stack gas (includes sulfur dioxide), fire, lightning, and gunfire as well as the combined effects of the space environment. 

Melting point (decomposes), °C 100 Relative density (water-1) 2.0 Solubility In water very good Relative molecular mass 238.1 Gross formula OgS2 COLORLESS CRYSTALS OR WHITE CRYSTALLINE POWDER Decomposes when heated or on exposure to air, giving off corrosive vapors (- sulfur dioxide end — sodium peroxide). Reacts violently with combustible substances and reducing agents, with risk of fire and explosion. ... 

Coal ash corrosion is a widespread problem for superheater and reheater tubes in coal fired power plants that bum high-sulfur coals. The accelerated corrosion is caused by liquid sulfates on the surface of the metal beneath an over-lying ash deposit. Coal ash corrosion is very severe between 540 and 740°C (1000°F and 1364°F) because of the formation of molten alkali iron-trisulfate. Considerable work has been done to predict corrosion rates based on the nature of the coal (its sulfur and ash content). This was accomplished by the exposure of various alloys to synthetic ash mixtures and synthetic flue gases. The corrosion rates of various alloys were repotted in the form of iso-corrosion curves for various sulfur dioxide, alkali sulfiite, and temperature combinations. An equation was developed to predict corrosion rates for selected alloys from details of the nature of ash by analyzing deposits removed from steam generator tubes and from test probes installed in a boiler [33]. Then laboratory tests were conducted using coupons of various tdloys coated with synthetic coal ash that was exposed to simulated combustion gas atmospheres. 

CADMIO (Spanish) or CADMIUM (7440-43-9) Cd Air exposure, especially of powdered form, may cause chemical to self-ignite. Finely divided material reacts violently with strong oxidizers, fused ammonium nitrate, bromine pentafluoride, lithium, nitryl fluoride, phosphorus trichloride, potassium chlorate carbon dioxide + heat, hydrozoic acid (possible explosion), nitric oxide, tellurium. Contact with acid forms explosive hydrogen gas. Contact with hexafluorobenzene forms a heat-sensitive explosive compound. May react with selenium, elemental sulfur, zinc. On small fires, use dry chemical powder (such as Puiple-K-Powder), foam, Halon, or CO2 extinguishers. 

HEXYL CARBITOL (112-59-4) CioH 0 Combustible peroxidizable liquid (flash point 285°F/141°C cc). Forms unstable peroxides on exposure to air. Violent reaction with oxidizers, boron trifluoride permanganates, peroxides and hydroperoxides, ammonium persulfate, bromine dioxide, sulfuric acid, nitric acid, perchloric acid, and other strong acids. Incompatible with acids, acyl halides, aliphatic amines, alkalis, boranes, isocyanates. On small fires,... 

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