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Removal cyanide

Ammonia stripping also removes cyanide, phenols, and other VOCs typically found in cokemaking wastewater. Phenols may also be removed by conversion into nonodorous compounds or into crude phenol or sodium phenolate by either biological means (phenol concentration <25 mg/L) or by physical processes.21 However, the Koppers dephenolization process is considered to be quite effective as it lowers the phenol content by 80 to 90% in ammonia still wastes. In this process a stream stripping process followed by mixing in a solution of caustic soda results in renewal of pure phenol with the flue gas.8... [Pg.69]

This section describes the treatment technologies currently in use to recover or remove wastewater pollutants normally found at coil coating facilities. The treatment processes can be divided into six categories recovery techniques, oil removal, dissolved inorganics removal, cyanide destruction, trace organics removal, and solids removal.5-14 Adoption of specific treatment processes will depend on the following ... [Pg.278]

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. [Pg.247]

The U.S. Bureau of Mines-Salt Lake Research Center is conducting research to develop new biohydrometallurgical techniques to decontaminate mining and milling wastes containing heavy metals and toxic chemicals. Bacterial techniques are being developed to remove cyanide and selenium from waste water. [Pg.192]

A natural development was to remove cyanide altogether from the bath. However, until recently, the bright ductile coatings which were characteristic of the cyanide processes could not be reproduced in the alkaline cyanide-free bath. The development of brighteners such as those discussed in Section 57.2.4 has now made this a viable process which avoids major effluent treatment problems. The current efficiency falls off with current density more rapidly than for the high cyanide-high metal bath, but in this respect it is no worse than the low cyanide bath. [Pg.13]

Nitrogen and/or sulphur present. To remove cyanide and sulphide ions, make 2-3 ml of the fusion solution just acidic with dilute nitric acid, and evaporate to half of the original volume in order to expel hydrogen cyanide and/or hydrogen sulphide which may be present (CAUTION). Dilute with an equal volume of water and proceed as in test (1), (2) and (3) above. [Pg.1208]

In the case of a mixed cyanide/nitrite waste stream, it is advisable to treat the effluent first at alkaline pH to remove cyanide before reducing the pH to the acid range for nitrite treatment. This reduces the risk of toxic hydrogen cyanide laden waste streams. [Pg.218]

Detection of halide ions. The alkaline solution from the sodium fusion is first treated with dilute nitric acid and boiled in the hood to remove cyanide and sulfide ions that may be present. These ions form insoluble precipitates with silver ion and interfere with the detection of halide ions. On boiling with dilute nitric acid they are volatilized as hydrogen cyanide and hydrogen sulfide hence care should be exercised, and the hood must be used in heating the test solution. The addition of silver ion forms a precipitate of silver halide which varies in color from yellow (iodide) to white (chloride and bromide). If it is necessary to identify the halide present, a portion of fresh solution is acidified with a few drops of dilute. sulfuric acid and a thin layer of chloroform (2-3 ml) is added, followed by a drop of freshly prepared chlorine water. On shaking, the chloroform layer becomes colorless if the ion is chloride, brown if it is a bromide, and violet if it is iodide. [Pg.89]

Cyanide Removal. Cyanide removal from waste liquors in gold processing is being commercialized at the Huang-hua Mountain Gold Plant, near Tian-jin, China (7,22,27,25). Table HI shows the ELM system for the cyanide removal (27), Cyanide can be reduced from about 130 mg/L to 0.5 mg/L with an extraction efficiency of 99.6%, leading to pollution control and productivity increase. In addition to Extractant M and Lan 113-b used by Tm and Zhang (27), an amine extractant, e.g., Alamine (Henkel), and a polyamine surfactant, e.g., EC A 11522 or Paranox 100, could constitute an effective ELM system for the cyanide removal. [Pg.213]

A primary goal in management is to remove cyanide from cytochrome oxidase so aerobic metabolism can resume. Since cyanide has a higher affinity for ferric iron, sodium nitrite is administered to oxidise haemoglobin (Fe " to methaemoglobin... [Pg.155]


See other pages where Removal cyanide is mentioned: [Pg.324]    [Pg.47]    [Pg.69]    [Pg.369]    [Pg.15]    [Pg.632]    [Pg.294]    [Pg.14]    [Pg.37]    [Pg.51]    [Pg.14]    [Pg.561]    [Pg.6159]    [Pg.279]    [Pg.145]    [Pg.133]    [Pg.327]    [Pg.25]    [Pg.503]    [Pg.1055]    [Pg.60]   
See also in sourсe #XX -- [ Pg.157 , Pg.158 ]




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