Cyanide Potassium, cyanide

Physical Properties. The physical properties of potassium cyanide are given in Table 6. Unlike sodium cyanide, potassium cyanide does not form a diliydrate. 

Many reactions can be carried out between potassium cyanide and organic compounds with the alkalinity of the KCN acting as a catalyst these reactions are analogous to reactions of sodium cyanide. The reactions of potassium cyanide with sulfur and sulfur compounds are also analogous to those of sodium cyanide. Potassium cyanide is reduced to potassium metal and carbon by heating it out of contact with air in the presence of powdered magnesium. Magnesium is converted to the nitride ... 

Hydrogen cyanide Calcium cyanide Potassium cyanide Sodium cyanide Hydrogen fluoride as F Hydrogen peroxide Hydrogen selenide as Se Hydrogen sulphide Hydroquinone... 

Cyanide Copper cyanide Nickel cyanide Potassium cyanide Silver cyanide Sodium cyanide Zinc cyanide... 

Amounts allowed range from 5 ppm in cucumbers, lettuce, radishes, and tomatoes, to 250 ppm in spices. EPA also requires industries to report spills of 1 pound or more of potassium silver cyanide and 10 pounds or more of hydrogen cyanide, potassium cyanide, sodium cyanide, calcium cyanide, or copper cyanide. 

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. 

Distribution. Cyanide is rapidly distributed by the blood throughout the body. In a study using orally administered radioactively labelled potassium cyanide, radioactivity detected in whole blood or plasma decreased rapidly within 6 hours. Of the low levels of radioactivity detected in the red blood cells, about 94% of the radioactivity recovered was found in the hemolysate of which 70% was detected in the heme fraction, 14-25% in globin, and only 5-10% in cell membranes (Farooqui and Ahmed 1982). Yamamoto et al. (1982) determined that the pattern of distribution of cyanide did not vary with the concentration used. Ballantyne (1983b) observed higher cyanide levels in whole blood than in serum in rabbits exposed dermally to hydrogen cyanide, potassium cyanide, and sodium cyanide. See Section 2.3.2.1 for specific studies on cyanide tissue distribution. 

In the section that follows, data needs are identified for cyanide forms for which toxicity data were available and were, therefore, summarized in Section 2.2. These forms include primarily sodium cyanide, potassium cyanide, and hydrogen cyanide. As seen from Figure 2-6, information is available regarding death, systemic effects of acute exposure, and neurological effects in humans after inhalation, oral, and dermal exposure to cyanide. In addition, information is available regarding chronic systemic effects in humans after inhalation and oral exposure. 

Characteristic Hydrogen cyanide Sodium cyanide Potassium cyanide Calcium 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. 

Cyanide occurs most commonly as hydrogen cyanide in water, although it can also occur as the cyanide ion, alkali and alkaline earth metal cyanides (potassium cyanide, sodium cyanide, calcium cyanide), relatively stable metallocyanide complexes (ferricyanide complex [Fe(CN)6]-3), moderately stable metallocyanide complexes (complex nickel and copper cyanide), or easily decomposable metallocyanide complexes (zinc cyanide [Zn(CN)2], cadmium cyanide [Cd(CN)2]). Hydrogen cyanide and cyanide ion combined are commonly termed free cyanide. The environmental fate of these cyanide compounds varies widely (Callahan et al. 1979). 

Environmental Fate. The environmental fate of hydrogen cyanide gas in air is well studied (Cicerone and Zellner 1983 Fritz et al. 1982) however, it would be useful if the role of particulate cyanides (e.g., sodium cyanide, potassium cyanide) in determining the fate of total cyanides in the air was known. Given that hydrogen cyanide occurs in the atmosphere from both natural and anthropogenic processes (Cicerone... 

Proposed Rule Deminimis Emissions for Determinations Regarding Modifications to Major Sources Sodium cyanide Potassium cyanide Other cyanide compounds 0.1 ton/yr 0.1 ton/yr 5 tons/yr 59 FR 15504 EPA 1994a... 

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... 

Guidelines a. Air ACGIH Threshold Limit Values for Occupational Exposure (TLV-TWA) Cyanogen TLV - Ceiling Hydrogen cyanide, sodium cyanide, calcium cyanide, potassium cyanide, acetone cyanohydrin Cyanogen chloride 21 mg/m3 5 mg/m3 0.75 mg/m3 ACGIH 1996... 

Cyanide, potassium silver cyanide, sodium cyanide, potassium cyanide... 

Synonyms/compounds Sodium cyanide potassium cyanide calcium cyanide ( black cyanide )... 

Sodium cyanide. Potassium cyanide. Sulfuric acid... 

Fluoride-Modified Copper Cyanide Copper cyanide Potassium cyanide Potassium fluoride... 

Cyanide. Potassium cyanide, [CAS 151-50-8], cyanide of potash, KCN, white solid, soluble, very poisonous, formed by reaction of calcium cyanamide and potassium chloride at high temperature. Used as a source of cyanide and for hydrocyanic acid, but usually replaced by the cheaper sodium cyanide. Also used in metallurgy, electroplating,... 

Related reactions of the substituted alkenes 176 and 178 with basic nucleophiles such as ammonia occur at C-3 and C-2, respectively, to give the thermodynamically favored gluco adducts 177200 and 179.201 Alternatively, the nitroalkene 178, under neutral or weakly acid conditions, adds nucleophiles such as hydrazoic acid, hydrogen cyanide-potassium cyanide, or purine bases at C-2 to give the a-manno products.201... 

The displacement of a nuclear halogeno substituent by a cyano group can be done fairly readily in the pyrazine series, usually by treatment with cuprous cyanide, potassium cyanide plus cuprous iodide, or potassium cyanide in the presence of a palladium catalyst. The following examples illustrate these procedures ... 

Nitrous acid, sodium nitrite, potassium nitrite hyponitrous acid and the hypo-nitrites hydrogen cyanide, potassium cyanide, cyanogen the cyanate ion, fulminate ion, azide ion, and thiocyanate ion. 

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

Silver-Lume A, B [ATOTECH]. TMfor a bright silver electroplating process for use by silversmiths and electronics manufacturers. The materials used are silver cyanide, potassium cyanide, potassium carbonate, and addition agents. 

Cyanogen chloride Hydrogen cyanide Potassium cyanide Sodium cyanide... 

In contrast to allyl halides substituted with one ASG, the cyclopropanation reaction proceeds relatively smoothly when a second ASG is present. Generally, the best results are obtained with sodium borohydride, sodium cyanide, potassium cyanide, and the sodium salts of alcohols or thiols as the nucleophilic species (Table 22, entries 3-26). Even spiroalkanes can be synthesized with the nucleophiles described above (Table 23). Examples illustrating this route are the conversion of a tetracyclic enamino ester with potassium cyanide to the corresponding electrophilic cyclopropane 2, and the facile one-pot synthesis of 1,1 -bis(hydroxymethyl)cyclo-propanes 3 by reduction of halogenated alkylidene malonates with lithium aluminium hydride. ... 

A cyano group can be introduced using palladium and zinc cyanide, potassium cyanide or potassium ferrocyanide, the last having the significant advantage of low toxicity, and can be carried out with either a paUadium " or copper catalyst. Tri-n-butyltin cyanide can be used similarly, but a modification using catalytic tri- -butyltin chloride with potassium cyanide is much to be preferred. ... 

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