Hydrogen fluoride, from combustion

A substantial portion of fhe gas and vapors emitted to the atmosphere in appreciable quantity from anthropogenic sources tends to be relatively simple in chemical structure carbon dioxide, carbon monoxide, sulfur dioxide, and nitric oxide from combustion processes hydrogen sulfide, ammonia, hydrogen chloride, and hydrogen fluoride from industrial processes. The solvents and gasoline fractions that evaporate are alkanes, alkenes, and aromatics with relatively simple structures. In addition, more complex... 

Chlorine dioxide Copper Fluorine Hydrazine Hydrocarbons (benzene, butane, propane, gasoline, turpentine, etc) Hydrocyanic acid Hydrofluoric acid, anhydrous (hydrogen fluoride) Hydrogen peroxide Ammonia, methane, phosphine or hydrogen sulphide Acetylene, hydrogen peroxide Isolate from everything Hydrogen peroxide, nitric acid, or any other oxidant Fluorine, chlorine, bromine, chromic acid, peroxide Nitric acid, alkalis Ammonia, aqueous or anhydrous Copper, chromium, iron, most metals or their salts, any flammable liquid, combustible materials, aniline, nitromethane... 

Anthropogenic sources of fluoride include fossil fuel combustion and industrial waste. Hydrogen fluoride is water soluble and emissions are readily controlled by acid gas scrubbers. HF emission from coal combustion, that is considered to be the main anthropogenic source of HF, was estimated to be 0.18 Tg annually emission of HF from the combustion of petroleum and natural gas is almost certainly negligible [24]. Apparently only limited data are available concerning total annual emissions of HF from industrial operations however, there is evidence that emissions of fluorides have been declining [24,25]. 

Continuous analysis of highly fluorinated materials can present problems, primarily caused by the corrosiveness of hydrogen fluoride which is liberated from all of them during combustion. Hydrogen fluoride will react with the permanently bound hydroxy groups on the surface of the cooler parts of combustion tube walls and catalysts. The effect can lead to erratic hydrogen values and so the installation of some type of oxide [magnesium oxide, alumina, or cerium (IV) oxide] trap in the combustion tube to prevent its escape is recommended. 11... 

Caution. Fluorine presents some, though not an extreme, hazard because of its toxicity. It ignites combustible materials spontaneously and may start laboratory fires. Wa.ste fluorine from the reaction should be discharged into a hood, and the waste vent should not be close to materials which will burn. Fluorine in high concentration burns human skin. The burn seems to be caused at least as much by heat as by the hydrogen fluoride produced by the reaction. 

Sodium fluoroacefafe (compound 1080 [CAS 62-74-8]) A highly toxic metabolic poison. Metabolized to fluorocitrate, which prevents the oxidation of acetate in the Krebs cycle. Human lethal oral dose ranges from 2 to 10 mg/kg. See also p 201. 0.05 mg/m S 2.5 mg/m Fluffy white solid or a fine white powder. Sometimes dyed black. Hygroscopic. Odorless. Vapor pressure is negligible at 20°C (68°F). Not combustible. Ther-mal-breakdovm products include hydrogen fluoride. Has been used as a rodenticide. 

In addition to the most conunon contaminants previously mentioned, pollutants such as hydrogen chloride, chlorine, hydrogen fluoride, and hydrogen bromide are produced as combustion products from the burning of chemical waste. When organophosphorous compounds are incinerated, corrosive phosphorous compounds are produced. Chlorides are also a product of municipal waste incinerators. 

The amount of ammonia consumed was obtained from the change in mass of a reservoir and the amount of hydrogen fluoride formed was determined after it had been absorbed by solid sodium fluoride. The accuracy of the result was limited principally by the uncertainty in the correction applied for the non-ideality of hydrogen fluoride. An improved calorimeter has been described in which the hydrogen fluoride formed is absorbed in water contained in a PTFE-lined vessel below the combustion chamber, so that the final product is an aqueous solution of hydrofluoric acid. This calorimeter has been used to study the reactions ... 

I mployee safety hazards may be invisible — yet cause as much damage as an approach-ling cyclone. Case in point hazardous gases, vapors and combustibles in the workplace, including carbon monoxide, ammonia, hydrogen fluoride, carbon dioxide and hydrogen cyanide, among others. These potentially toxic contaminants must be monitored to protect workers from adverse health reactions and maintain OSHA compliance. 

ANILINE (62-53-3) Combustible liquid (flash point 158°F/70°C). Unless inhibited (usually by methanol), readily able to polymerize. Violent reaction, including the possibility of fire, explosion, and the formation of heat- or shock-sensitive compounds may result from contact with acetic anhydride, benzene diazonium-2-carboxylate, aldehydes, alkalis, benzenamine hydrochloride, boron trichloride, l-bromo-2,5-pyrrolidinedione, chlorosulfonic acid, dibenzoyl peroxide, fluorine nitrate, halogens, hydrogen peroxide, isocyanates, oleum, oxidizers, organic anhydrides, ozone, perchloryl fluoride, perchromates, potassium peroxide, P-propiolactone, sodium peroxide, strong acids, trichloromelamine. Strong reaction with toluene diisocyanate. Reacts with alkaline earth and alkali metals. Attacks some plastics, rubber, and coatings. Incompatible with copper and copper alloys. 

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