Containing hydrogen chloride toxicity

HARTZELL ET AL. Toxicity of Smoke Containing Hydrogen Chloride... 

Hartzell, G.E. Grand, A.F. Switzer, W.G. "Modeling of Toxicological Effects of Fire Gases VI. Further Studies on the Toxicity of Smoke Containing Hydrogen Chloride," J. Fire Sciences 1987, 5(6), 368-391. 

Modelling of toxicological effects of fire gases. VI. Further studies on the toxicity of smoke-containing hydrogen chloride. J. Fire Sci. 5(6) 368-91. 

Hartzell, G.E. et al. (1990) Toxicity of smoke containing hydrogen chloride,... 

The most important class of stabilisers are the lead compounds which form lead chloride on reaction with hydrogen chloride evolved during decomposition. As a class the lead compounds give rise to products of varying opacity, are toxic and turn black in the presence of certain sulphur-containing compounds but are good heat stabilisers. 

Fire Hazards - Flash Point (deg. F) 252 OC Flammable Limits in Air (%) Not pertinent Fire Extinguishing Agents Water Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Toxic fumes include oxides of phosphorous, sulfur and hydrogen chloride Behavior in Fire Containers may rupture Ignition Temperature (deg. F) 338 Electrical Hazard No data Burning Rate No data. 

While ethyl chloride is one of the least toxic of all chlorinated hydrocarbons, CE is a toxic pollutant. The off-gas from the reactor is scrubbed with water in two absoiption columns. The first column is intended to recover the majority of unreacted ethanol, hydrogen chloride, and CE. The second scrubber purifies the product fiom traces of unreacted materials and acts as a back-up column in case the first scrubber is out of operation. Each scrubber contains two sieve plates and has an overall column efficiency of 65% (i.e., NTP = 1.3). Following the scrubber, ethyl chloride is finished and sold. The aqueous streams leaving the scrubbers are mixed and recycled to the reactor. A fraction of the CE recycled to the reactor is reduced to ethyl chloride. This side reaction will be called the reduction reaction. The rate of CE depletion in the reactor due to this reaction can be approximated by the following pseudo first order expression ... 

Vent gases containing EDC vapour, not only from the storage and transport of EDC, but also from the EDC unit itself, must be controlled because of EDC toxicity and other reasons. Conventionally these vent emissions are controlled using thermal oxidation, where the EDC vapour is converted to carbon dioxide, water, and hydrogen chloride. The latter is then scrubbed from the flue gases, resulting in a byproduct hydrochloric acid stream. Consideration is required as to how this stream can be used or disposed of. 

Hydrochloric acid. Strong acids are used frequently for the purpose of sample dissolution when water will not do the job. One of these is hydrochloric acid, HC1. Concentrated HC1 is actually a saturated solution of hydrogen chloride gas, fumes of which are very pungent. Such a solution is 38.0% HC1 (about 12 M). Hydrochloric acid solutions are used especially for dissolving metals, metal oxides, and carbonates not ordinarily dissolved by water. Examples are iron and zinc metals, iron oxide ore, and the metal carbonates of which the scales in boilers and humidifiers are composed. Being a strong acid, it is very toxic and must be handled with care. It is stored in a blue color-coded container. 

These liquids are not normally miscible with water and are heavier than it, which is why there is no distinct phase border. Salts containing a tetrafluoroborate or hexafluorophosphate (V) anion are stable in air and in contact with water, but salts containing a tetrachloroaluminum ion are sensitive to water, reacting violently with it to produce toxic hydrogen chloride. 

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