Cyanide hydrogen cyanide

Another important environmental issue is the fate of cyanide. Hydrogen cyanide, if spilled, evaporates quite readily. That which does not evaporate is soon decomposed or rendered nonha2ardous by complexing with iron in the soil, biological oxidation, or polymeri2ation. 

Chlorination/oxidation of cyanide wastes from heat treatment plant Mixing cyanide with acids liberates hydrogen cyanide Hydrogen cyanide... 

Some properties of potassium cyanide, hydrogen cyanide, and sodium cyanide... 

Table 15.1 Some Properties of Potassium Cyanide, Hydrogen Cyanide, and Sodium Cyanide... 

Property Potassium Cyanide Hydrogen Cyanide Sodium Cyanide... 

Pesce, L.D. 1994. Cyanides Hydrogen cyanide. In Kirk-Othmer Encyclopedia of Chemical Technology, Vol. 7, 4th ed. John Wiley Sons, New York, pp. 753- 765. 

OSHA sets levels of cyanide that are allowable in workplace air. The permissible exposure limit (PEL) for cyanide salts is 5 milligrams of cyanide per cubic meter of air (mg/m3) averaged over an 8-hour workday and 40-hour workweek. NIOSH sets guidelines for chemicals in workplace air. Their recommended exposure limit (REL) for workers for 10 minutes is 5 mg/m3 for calcium cyanide, hydrogen cyanide, potassium cyanide, and sodium cyanide. 

Cyanide (reported as cyanide, hydrogen cyanide, sodium cyanide, potassium cyanide, or copper(I) cyanide) has been identified in at least 406 of 1,428 current or former hazardous wastes sites that have been proposed for inclusion on the EPA National Priorities List (NPL) (HazDat 1996). However, the number of sites evaluated for cyanide is not known. The frequency of these sites within the United States can be seen in Figure 5-1. 

Health-Based Limits for Exclusion of Waste - Derived Residues Calcium cyanide Copper cyanide Cyanogen sodium cyanide Hydrogen cyanide Potassium cyanide Potassium silver cyanide 1x1 O 6 mg/kg 2x1 O 1 mg/kg 1 mg/kg 7x1 O 5 mg/kg 2 mg/kg 7 mg/kg 40 CFR 266, App VII EPA 1991c... 

Liquid hydrogen cyanide, hydrogen cyanide in aqueous solution (hydrocyanic acid), and concentrated vapor are absorbed rapidly through the intact skin and may cause poisoning with little or no irritant effect on the skin itself. The liquid in the eye may cause some local irritation the attendant absorption may be hazardous. ... 

Hydrogen Cyanide and Cyanides Hydrogen cyanide is a highly toxic, volatile substance (bp 26°C) produced when metal cyanide solutions are acidified ... 

Cyanides (CN -compounds) are hydrogen cyanide (hydrogen cyanide, HCN) salts. In this case, specifically ferro(III)-ferri(II)-cyanide, but one can expect to find all sorts of iron cynaide compounds in mortar of facilities exposed to HCN. 

Double decomposition of ammonium sulphate and potassium aurocyanide yields ammonium aurocyanide, NH4Au(CN)2. This substance begins to decompose at 100° C. into aurous cyanide, hydrogen cyanide, and ammonia.7 Sodium aurocyanide, NaAu(CN)2, resembles the corresponding potassium salt in both preparation and properties. Salts of the aurocyanic radical, Au(CN)2, with other metals are also known.8 The compound HAu(CN)2 has not been isolated, since it decomposes readily with production of hydrogen cyanide. 

Blood Agents Cyanide (Hydrogen Cyanide, Cyanogen Chloride, Sodium Cyanide, Potassium Cyanide)... 

Anonymous, Cyanides (Hydrogen Cyanides), in Kirk-Othmer Encyclopedia of Chemical Technology, 2nd ed., 1965,... 

Cyanide. Hydrogen cyanide is weakly acidic (pK = 9.3). Cyanide ion reacts to form complexes with many transition metals. The quaternary nickel-cyanide complex, Ni(CN)4 , is extraordinarily stable (log 4 = 31.8) and dominates the simple aqueous chemistry of nickel as shown in Figure 15. At total cyanide concentrations of and above,... 

Corrosives in contact with a poison may produce poison gases as the poison decomposes. In responding to an incident involving corrosives, the toxicity of the vapors could be much more of a concern for personnel than the corrosivity. When acids come in contact with cyanide, hydrogen cyanide gas, which is highly toxic, with a TLV of 10 ppm in air, is produced. The structure and molecular formula of phosphorous trichloride are shown in Figure 10.8. 

D. Cyanides include cyanide, hydrogen cyanide, and cyanogen chloride. These compounds have high affinity for metalloenzymes such as cytochrome aa3, thus derailing cellular respiration and forcing the use of anaerobic metabolism and the development of lactic acidosis. 

Dimethylamine Dimethylphosphoramidate Dimethylphosphoramide cyanidate Ethyl A, A -dimethylamido phosphoric acid Ethylphosphoral cyanidate Hydrogen cyanide Phosphorocyanidate... 

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