Sodium copper cyanide

Sodium cuproferrocyanide, Na2Cu2Fe(CN)6, results 1 on adding a cold, saturated solution of sodium copper cyanide to a hot solution of sodium ferrocyanide or by boiling a solution of sodium ferrocyanide with cuprous cyanide in the presence of a little sodium sulphite, and cooling m an atmosphere of hydrogen. It crystallises m minute, colourless hexagonal prisms, which are conveniently dried over sulphuric acid in a vacuum. 

Sodium copper cyanide A mixed cyanide prepared from NaCN with CuCN, used to convert vinyl bromides to vinyl cyanides. 

Cyanide Disinfectants SPA Sodium cyanide Copper cyanide Heat treatment of metal Coal distillation Electroplating Photographic Synthetic fibre Agriculture and horticulture Abattoirs Eood processing... 

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

Cyan-kalium, n. potassium cyanide, -kalium-losung, /. potassium cyanide solution, -ko-balt, m. cobalt cyanide, -kohlensaure, / cyanocarbonic acid. -kupfer, n. copper cyanide, -laugerei, -laugung, /. cyaniding. cyanidation. -losung, / cyanide solution, -metall, n. metallic methyl cyanide, -natrium, n. sodium cyanide. -platin, n. platinum cyanide. 

Modern solutions fall mainly into three types (a) the plain cyanide bath which contains typically 20-25 g/1 of copper cyanide, 25-30 g/1 total sodium cyanide (6.2 g/1 free sodium cyanide), and is operated at 21-38 C and 110-160 A/m (b) the Rochelle copper bath to which is added 35-50g/1 of Rochelle salt and which is used at 66 C at up to 645 A/m and (c) the high-efficiency cyanide baths which may contain up to 125 g/1 of copper cyanide, 6-11 g/1 of free sodium or potassium cyanide, 15-30 g/1 of sodium or potassium hydroxide, and are operated at up to 6-9A/dm and 65-90 C. Most bright cyanide copper baths are of the high-efficiency type and, in addition, contain one or more of the many patented brightening and levelling agents available. Periodic reverse (p.r.) current is also sometimes used to produce smoother deposits. 

Cyanide solutions are used almost exclusively. One typical solution contains copper cyanide 26 g/1, zinc cyanide 11 g/1, sodium cyanide (total) 45 g/1 and sodium cyanide ( free ) 7 g/l This bath is operated at pH 10.3-11.0, 110 A/m and 27-35 C, with 75 Cu-25 Zn alloy anodes. Many other solutions are used including a special rubber-bonding bath and a high-speed bath which is capable of being used at up to 16 A/dm . ... 

Skin Contact Wash skin at once to remove cyanide while removing all contaminated clothing including shoes do not delay Skin absorption can take place from cyanide dust, solutions, or hydrogen cyanide vapor. Absorption is slower than with inhalation, often measured in minutes rather than seconds (AC or HCN is absorbed much faster than metal cyanides from solutions such as sodium, potassium or copper cyanide solutions). After going though decontamination on the victim(s), watch him or her for at least one to two hours, if possible, since absorbed cyanide can continue to work into the blood stream. As a final note, wash clothing before reuse, and destroy contaminated shoes. 

Several studies of occupational exposures and one study with a human subject were located. In the occupational exposures (summarized in Table 5- 3), neurological symptoms consistent with cyanide intoxication were demonstrated, but the likelihood of concomitant exposure to other chemicals could not be ruled out. For example, cleaners and cutting oils, as well as sodium and copper cyanide, may be present in electroplating operations (ATSDR 1997). The experimental human study involved the exposure of a single subject and a dog to a high concentration for a short exposure period. 

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. 

Oral exposure to cyanide usually results from accidental, homicidal, or suicidal ingestion of cyanide salts. Sodium cyanide and potassium cyanide are the most frequently studied cyanide compounds. Copper cyanide, potassium silver cyanide, silver cyanide, and calcium cyanide are other compounds that humans could encounter through oral or dermal exposure. Cassava roots and certain fruit pits contain compounds that can be broken down to form cyanide. Cassava roots form the staple diet of some populations in Africa, Central and South America, and Asia. However, it must be noted that cassava roots are notoriously deficient in protein and other nutrients and contain many other compounds, in addition to cyanide, that could be responsible for some of the observed toxic effects. Thiocyanate is a metabolite of cyanide that is formed in the body after exposure to cyanide compounds. When possible, all oral exposures are expressed as mg CN/kg/day. 

Dyspnea was observed in workers chronically exposed (5-15 years) to 6.4-10.4 ppm of an unspecified cyanide form evolved from sodium cyanide and copper cyanide during electroplating (El Ghawabi et al. 1975) and in workers exposed to 15 ppm hydrogen cyanide (14 ppm cyanide) in a silver-reclaiming... 

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). 

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... 

List of Hazardous Substances and Reportable Quantities Ammonium thiocyanate Calcium cyanide, cyanogen chloride, sodium cyanide, copper cyanide Cyanides (soluble salts complexes) Cyanogen Potassium silver cyanide 5,000 lbs 10 lbs 10 lbs 100 lbs 1 lb 40 CFR 302.4 EPA 1985e... 

Copper cyanide, cyanide, potassium silver cyanide, sodium cyanide... 

---