Trichloroethylene, combustion

X. Wang synthesized lanthanum-incorporated SBA-15 mesoporous catalytic materials via two-step synthesis method, and studied its catalytic activity in trichloroethylene combustion. The experimental results showed that there are a large amount of La entering SBA-14 framework imder suitable PH value, but the La-modified SBA-15 remained a highly ordered mesoporous structure as well as lanthanum modified SBA-15 exhibited better catalytic performance than SBA-15 without La addition in the combustion of trichloroethylene [180]. 

The recommended method of trichloroethylene disposal is incineration after mixing with a combustible fuel (Sittig 1985). Care should be taken to carry out combustion to completion in order to prevent the formation of phosgene (Sjoberg 1952). Other toxic byproducts of incomplete combustion include polycyclic aromatic hydrocarbons and perchloroaromatics (Blankenship et al. 1994 Mulholland et al. 1992). An acid scrubber also must be used to remove the haloacids produced. 

Mulholland JA, Sarofim AF, Sosothikul P, et al. 1992. Formation of perchloroaromatics during trichloroethylene pyrolysis. Combustion and Flame 89 103-115. 

Indeed, trichloroethylene treated by concentrated sodium hydroxide produces dichloroacetylene, which combusts spontaneously. 

Source Hexachlorobenzene may enter the environment from incomplete combustion of chlorinated compounds including mirex, kepone, chlorobenzenes, pentachlorophenol, PVC, polychlorinated biphenyls, and chlorinated solvents (Ahling et al., 1978 Dellinger et al., 1991). In addition, hexachlorobenzene may enter the environment as a reaction by-product in the production of carbon tetrachloride, dichloroethylene, hexachlorobutadiene, trichloroethylene, tetrachloro-ethylene, pentachloronitrobenzene, and vinyl chloride monomer (quoted, Verschueren, 1983). 

Mixtures of lithium shavings and several halocarbon derivatives are impact-sensitive and will explode, sometimes violently [1,2]. Such materials include bromoform, carbon tetrabromide, carbon tetrachloride, carbon tetraiodide, chloroform, dichloromethane, diiodomethane, fhiorotrichloromethane, tetrachloroethylene, trichloroethylene and 1,1,2-trichlorotrifluoroethane. In an operational incident, shearing samples off a lithium billet immersed in carbon tetrachloride caused an explosion and continuing combustion of the immersed metal [3]. Lithium which had been washed in carbon tetrachloride to remove traces of oil exploded when cut with a knife. Hexane is recommended as a suitable washing solvent [4]. A few drops of carbon tetrachloride on burning lithium was without effect, but a 25 cc portion caused a violent explosion [5]. 

The w,causes electrochemical exchange between the Mg and the Ag ion. The heat of reaction of this exchange provokes the pyrochemical effect. I a peroxide oxidizes Mg powd with incandescence (Ref 5). The mixt explodes when Heated to redness. When the mixt is exposed to moist air spontaneous combustion occurs., When carbon dioxide gas is passed over a mixt of powd Mg and Na peroxide, the mixt explodes (Ref 6). Stannic oxide, heated with Mg, explodes (Ref 13)., A mixt of sulfates and Mg may cause an expln (Ref 17.) It has been detd experimentally that a mixt of Mg powd with trichloroethylene or carbon tetrachloride will flash or spark under, Heavy impact (Ref 2l). Mg alloy powders contg more than 50% Mg readily ignite in air (Ref 20)... 

A 1980 Naval Research Laboratory report provides data on the toxic combustion products evolved by burning polyphosphazene foams, with and without fire retardants. Toxicants produced were CO, CO2, 2-chlorobutane, 1-chlorobutane, benzene, toluene, and trichloroethylene (for foams not coated with fire-retardant paints) (11). 

Thermal destruction systems have become recognized over the past decade as an increasingly desirable alternative to the more traditional methods of disposing of hazardous wastes in landfills and injection wells. What are some of the problems in the combustion of substances such as methylene chloride, chloroform, trichloroethylene, waste oil, phenol, aniline, and hexachloroethane ... 

Hexachlorobutadiene is an industrial by-product of tetrachloroethylene, trichloroethylene, and perchloro-ethylene production and is used as a solvent for elastomers, heat transfer liquids, transformer fluids, and hydraulic fluids. Hexachlorobutadiene may still be used in certain countries as a fumigant. It is also released during refuse combustion and is found in fly ash. 

Some VOCs can be malodorous pollutants, sensory irritants, or hazardous air pollutants. Hazardous VOC air pollutants include acetaldehyde, benzene, carbon tetrachloride, chloroform, ethylbenzene, formaldehyde, hexane, methylene chloride, naphthalene, paradichlorobenzene, pesticides (biocides), styrene, tetrachloroethylene, toluene, trichloroethylene, and xylenes. They are found in essentially all indoor locations, released by off gassing from numerous sources, such as construction and decorating materials, consumer products, paints, paint removers, furnishings, carpets, and from combustion of wood, kerosene, and tobacco. While more than 500 VOCs have... 

Properties Yellowish-brown, opaque to translucent solid. D 0.983, mp 67-68C, saponification value 65, iodine number 37, refr index 1.4555. Soluble in chloroform, turpentine, carbon tetrachloride, trichloroethylene, toluene, hot petroleum ether, and alkalies insoluble in water. Combustible. 

Properties Molecular weight 2000-5000. Translucent white solids, excellent electrical resistance, abrasion resistant, resistant to water and most chemicals, d 0.92. Slightly soluble in turpentine, petroleum naphtha, xylene, and toluene at room temperature soluble in xylene, toluene, trichloroethylene, turpentine, and mineral oils at 82.2C practically insoluble in water slightly soluble in methyl acetate, acetone, and ethanol up to the boiling points of these solvents. Available as emulsified and nonem-ulsified forms. Combustible. 

The increasing amounts of chlorinated volatile organic compounds (VOC), such as 1,2-dichloroethane (DCE) and trichloroethylene (TCE), released in the environment, together with their suspected toxicity and carcinogenic properties, have prompted researchers world-wide to find clean effective methods of destruction [1]. The abatement of chlorinated volatile organic compounds by catalytic combustion has been widely utilised in several technical processes. The lower temperatures required for catalytic combustion result in a lower fuel demand and can therefore be more cost effective than a thermal oxidation process [2]. In addition, the catalytic process also exerts more control over the reaction products and is less likely to produce toxic by-products, like dioxins, which may be generated by thermal combustion [3]. 

Kosusko et al. [160, 161] reviewed studies for the destruction of groundwater air-stripping emissions. The catalyst consisted of a precious metal deposited on a ceramic honeycomb. Typical organic compounds in air stripping overhead are pentane, cyclohexane, trichloroethylene, benzene, cumene, etc. Catalyst deactivation occurs when H2S is present in the ground water or when aerosols are stripped. Figure 31 shows an example of a system used for the purification of stripped air. Air is treated countercurrently with a contaminated water stream. Downstream from the demister the contaminated gas is heated by an external source such as the combustion of natural gas. Part of the contaminants will be oxidized. 

Chang, W. D., and Senkan, S. M., Chemical structure of fuel-rich, premixed, laminar flames of trichloroethylene. Symp. (Int.) Combust. [Proc.], 22, 1453 (1988). 

EPIHYDRIN ALCOHOL (556-52-5) CjHjOj The pure material or a solution in water is sensitive to moisture, light, and temperature it may polymerize when heated above room temperature. Combustible and polymerizable liquid (flash point 158°F/70°C). Reacts violently with strong oxidizers. Contact with strong acids, bases, caustics, chemically active metals (aluminum, copper, zinc, etc.), metal salts, trichloroethylene, especially in the presence of heat, can cause polymerization or exothermic decomposition. Incompatible with nitrates. Attacks some plastics, rubber, and coatings. 

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