Ammonium chloride smoke

Solid particulates are captured as readily as hquids in fiber beds but can rapidly plug the bed if they are insoluble. Fiber beds have frequently been used for mixtures of liqmds and soluble sohds and with soluble solids in condensing situations. Sufficient solvent (usually water) is atomized into the gas stream entering the collector to irrigate the fiber elements and dissolve the collected particulate. Such nber beds have been used to collect fine fumes such as ammonium nitrate and ammonium chloride smokes, and oil mists from compressed air. 

In the other method, particularly popular in Germany, the ammonium nitrate is replaced by an equimolar mixture of ammonium chloride and potassium or sodium nitrate. The reaction between the salts, which gives potassium or sodium chloride and ammonium nitrate or its decomposition products, is relatively slow and does not occur to a marked extent when the explosive is fired in an unconfined condition. This method of working is particularly effective in reducing the power of an explosive in the unconfined condition. Used alone it has not proved popular in Britain, because of the low power which tends to be developed under practical firing conditions. Moreover, the finely divided sodium chloride smoke which is produced by the explosive tends to be unpleasant for the miners. 

Addition of ammonium chloride to a drum of weed-killer was suspected as the cause of a violent explosion (involving formation of ammonium chlorate) [1]. Mixtures, used for smoke compositions, are hazardous [2],... 

If this reaction occurs, the chance of spontaneous ignition of the mixture is likely. Therefore, any composition containing both a chlorate salt and an ammonium salt must be considered extremely hazardous. The shipping regulations of the United States Department of Transportation classify any such mixtures as "forbidden explosives" because of their instability [8]. However, compositions consisting of potassium chlorate, ammonium chloride, and organic fuels have been used, reportedly safely, for white smoke production [Ij. 

Burning at subatmospheric pressure is accompanied by the evolution of white fumes which solidify upon contact with a cold surface. For the LP3 propellant, it is larger in quantity and increases considerably as soon as the ash starts forming. This smoke was found to contain 25% ammonium perchlorate and 55% ammonium chloride. A trap was installed to determine the amount of smoke evolved per unit mass of propellant as a function of pressure and oxidizer particle size, but the results were inconclusive. The weight of sublimate caught was approximately 20% of the original weight of the propellant. 

Mercuric Ammonium Chloride— Fire Hazards Flash Point (deg. F) Not flammable, Flammable Limits in Air (%>) Not flammable Fire Extinguishing Agents Not pertinent Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Smoke may contain toxic mercury compounds Behavior in Fire Not pertinent Ignition Temperature... 

However with poor ventilation they seem to give more persistent smoke than compositions based on ammonium nitrate and sodium chloride. Analysis of the smoke showed it to be due to finely divided ammonium chloride suspended in moist air, and although not harmful it may be objectionable to the miners. In addition, calcium sulphate was included to suppress the smoke (J. Taylor and Gay [4]). Calcium nitrate found only a limited use as a substance for lowering the temperature of detonation flame. 

HOLD ON TO AMMONIA-FILLED JAR AND PULL CARDBOARD AWAY. IMMEDIATELY, BOTH JARS FILL WITH "SMOKE" OF TINY AMMONIUM CHLORIDE CRYSTALS. 

White smoke is produced by burning a mixture of potassium chlorate 3 parts, lactose 1, and finely powdered ammonium chloride 1. The smoke, which consists of finely divided ammonium chloride, is not poisonous, and has found some use in connection with the study of problems in ventilation. 

Bassam Z. Shakhashiri, "Preparation and Properties of Ammonia/ Chemical Demonstrations, A Handbook for Teachers of Chemistry, Vol. 2 (The University of Wisconsin Press, Madison, 1985), pp. 202-204. Ammonia gas is produced from the reaction of ammonium chloride with calcium hydroxide and is collected in an Erlenmeyer flask by the displacement of air. The ammonia gas turns moistened litmus paper blue, demonstrating the basic properties of ammonia dissolved in water. When the mouth of an ammonia-filled Erlenmeyer flask is placed below the surface of a pool of water, water rapidly enters the flask to replace ammonia that dissolves in the water. White smoke forms when ammonia vapor is passed over the top of a beaker of concentrated hydrochloric acid forming solid ammonium chloride. 

The smoke with ammonia is due to the precipitation of solid ammonium chloride where the gases HC1 and NH3 meet. The ammonium hydroxide dissociates non-electrolytically... 

Composition A smoke mixture containing zinc dust, hexachlorethane, ammonium perchlorate, ammonium chloride, and calcium carbonate. 

Properties On ignition, reaction between zinc dust and hexachlorethane produces zinc chloride and free carbon, both of which pass off in the smoke. The ammonium perchlorate keeps the reaction going, ammonium chloride readily volatilizes and controls the rate of burning, and calcium carbonate stabilizes the mixture by taking up any hydrochloric acid which may be present. The smoke is harmless. 

Chemical Means of Dispersion,—SVhen the primary dispersion i pffecteii by a chemical process, two substances in a gaseous state are simultaneously emitted and, by chemical reaction on each other, yield a liquid or solid compound in the dispersed state. Thus, gaseous hydrochloric acid and ammonia yield ammonium chloride in the form of a dense white fume. Similarly, sulfuric acid fumes formed by the hydration of sulfuric anhydride form, on contact with ammonia ammonium sulfate, another dense w hite smoke, thus ... 

These charts indicate typical relations between T.O.P. and the factors that principally affect it. While relations apply in general to all smokes, there are some notable exceptions the T.O-P. of phosphorus, c.p., i unaffected by temperature, and the T.O.P. of ammonium chloride is unaffected by humidity. However, these are not important, for, while there are a few exceptions to the T.O.P.-temperature law shown in Chart XVII, ammonium chloride and earlKin smokes (such as those generated by cnidc oil) arc the only smokes that depart from the T.O.P.-hnmidity law, show n in Chart X T. 

The. smoke ntixtiire was < ompo ed of hcxachloretliane, powdt-red zine, ummoniiim perchlorate, and ammonium chloride, and the starting mixture oon.si.sted of potassium nitrate, antimony trisulfido, and dextrine. 

Bonfire smoke is produced under the same principle described for black and white smoke. But the difference is that in the case of the bonfire the particles of smoke only absorb the moisture little and do not always grow to a visible size. The smoke therefore sometimes looks almost violet in the distance. The moisture in the air has a great influence upon the growth of the particles of the A-substance when it is hygroscopic. For example, in dry weather a zinc chloride smoke looks thin. A composition which contain ammonium perchlorate, e.g. a colour flame composition or a rocket propellant, has smoke which is almost invisible in dry weather, but it looks quite dense in wet weather. This is due to HCl in the burning gas. A particle of water mist dissolves 00 times its volume of HCl gas at normal temperature. if there is some water mist in the air, the... 

The smoke composition which contains auramine and potassium chlorate is said to cause spontaneous ignition(Yamanaka and Mitsuo, Showa Kaseihin Co.), but when the composition is in a well dried state there should not be such a problem. The reason is not clear, but it may come from the ammonium chloride which is used for manufacturing auramine and which remains in it as an impurity. As described before, the mixture of an ammonium salt and potassium chlorate creates ammonium chlorate which easily decomposes. ... 

This study resulted in a series of reports on a comprehensive evaluation of fire-retardant treatments for wood (2-6). One hundred and thirty single chemicals or combinations of chemicals in the form of various salts were evaluated for flame-spread reduction, smoke, and corrosivity. Diammonium phosphate ranked first in reducing flame spread, followed by monoammonium phosphate, ammonium chloride, ammonium sulfate, borax, and zinc chloride. Zinc chloride, although excellent as a flame retardant, promoted smoke and glowing. Ammonium sulfate was the least expensive, but under certain environmental conditions it was corrosive to metals. None of the 130 compositions tested was considered ideal because of the adverse effects on some of the properties of wood. Several reviews of the subject are available and provide additional background material (J, 7-JO). 

Caution. The entire preparation should be carried out in a well-ventilated fume hood in order to avoid inhaling gaseous hydrogen chloride, or smoke of ammonium chloride. 

The smoke consists mainly of water, ammonia, ammonium chloride and iiiiro-gen. However, its composition has still not been exactly determined, and it is possible that highly toxic compounds may be present in small amounts. 

HCI(g) and NH3(g) react to form NH4CI(s). Gases from the concentrated aqueous solutions react to form a smoke of solid ammonium chloride. 

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