Oxidative Cyanide

Cyanide [57-12-5] Cyanide detoxification Cyanide exchange Cyanide iron blue Cyanide oxidation Cyanides... 

Ozone can be used to completely oxidize low concentrations of organics in aqueous streams or partially degrade compounds that are refractory or difficult to treat by other methods. Compounds that can be treated with ozone include alkanes, alcohols, ketones, aldehydes, phenols, benzene and its derivatives, and cyanide. Ozone readHy oxidizes cyanide to cyanate, however, further oxidation of the cyanate by ozone proceeds rather slowly and may require other oxidation treatment like alkaline chlorination to complete the degradation process. 

The special properties of lipoic acid arise from the ring strain experienced by oxidized lipoic acid. The closed ring form is approximately 20 kj higher in energy than the open-chain form, and this results in a strong negative reduction potential of about —0.30 V. The oxidized form readily oxidizes cyanides to isothiocyanates and sulfhydryl groups to mixed disulfides. 

Ozonation treatment can be used to oxidize cyanide, thereby reducing the concentration of cyanide in wastewater. Ozone, with an electrode potential of +1.24 V in alkaline solutions, is one of the most powerful oxidizing agents known. Cyanide oxidation with ozone is a two-step reaction similar to alkaline chlorination.22 Cyanide is oxidized to cyanate, with ozone reduced to oxygen as per the following equation ... 

Taurog et al. [216] showed that contrary to previous suggestions, both iodination and coupling are catalyzed by the oxoferryl porphyrin Tr-cation radical of TPO Compound I and not the oxoferryl protein radical. HRP catalyzed the oxidation of bisulfite to sulfate with the intermediate formation of sulfur trioxide radical anion S03 [217] HPO, MPO, LPO, chloroperoxidase, NADH peroxidase, and methemoglobin oxidized cyanide to cyanyl radical [218],... 

CNC A chemical/biological process for oxidizing cyanide ion in wastewater. The waste-water is mixed with a proprietary soluble reagent and passed through a biological reactor in which cyanide is oxidized to carbon dioxide and nitrogen. Developed and offered by Radian Corporation, Austin, TX. 

Chemical/Physical. Emits toxic fumes of nitrogen oxides, cyanides, and chlorine when heated to decomposition (Sax and Lewis, 1987). Chlorothalonil is resistant to hydrolysis under acidic conditions. At pH 9, chlorothalonil (0.5 ppm) hydrolyzed to 4-hydroxy-2,5,6-trichloroisophthalo-nitrile and 3-cyano-2,4,5,6-tetrachlorobenzamide. Degradation followed first-order kinetics at a rate of 1.8% per day (Szalkowski and Stallard, 1977). 

The monitoring of cyanide with microbial sensor is possible in two ways. The first principle is based on the inhibition of respiration of Saccharomyces cervisiae by cyanide [102, 103]. This sensor showed a linear response in the range 0-15 pmol 1 by a response time of approximately 10 min and a stability of 9 days. Another method for the determination of cyanide is enabled by the use of cyanide-degrading microorganisms such as Pseudomonas fluorescens [1041. This bacterium specifically oxidizes cyanide by consuming oxygen ... 

The close proximity of the a3 and CuB centres has been demonstrated for the low-spin oxidized cyanide complex, where the cyanide acts as a bridging ligand between a3 and CuB. 

The rust content (Fc203) of Portland cement, of particular interest to us here, the cement most frequently used for concrete and cement mortars, is usually between 1 and 5%.396 The sand added to the mortar can also exhibit a high iron content (up to 4%). As mentioned in chapter 6.5. 3., a large surface area at the solid-liquid phase limit (iron oxide-cyanide solution) is favorable to the formation of Iron Blue. This is extraordinarily large in cement and concrete mortars (microscopic inte-... 

Chlorine in elemental or hypochlorite salt form is a strong oxidizing agent in aqueous solution and is used in water treatment for disinfection, and in industrial waste treatment facilities primarily to oxidize cyanide. Chlorine and hypochlorites can also be used to oxidize phenol-based chemicals, but their use is limited because of the formation of toxic chlorophenols if the process is not properly controlled. 

The cyanide alkaline chlorination process uses chlorine and caustic to oxidize cyanides to cyanates and ultimately to carbon dioxide and nitrogen. The oxidation reaction between chlorine and cyanide is believed to proceed in two steps as follows, according to Eqs. (11) and (12) ... 

At least one accident is known where liquid NC13 could separate in a waste-water treatment where bleach was used to oxidize cyanide ions. After an agitation failure, the actuation of a bottom valve triggered the detonation. Direct chlorination would lead to the same dangerous situation. 

TETRINE ACID (60-00-4) CioH.sNjOg A weak organic (carboxylic) acid. Reaction with dithiocarbamates, isocyanates, mercaptans, nitrides, nitrites, sulfides, forms flammable and/or toxic gases + heat. Incompatible with acids, azo compounds, epoxides and other polymerizable compounds oxidizers, sulfuric acid, reducing agents bases, ammonia, aliphatic amines alkanolamines, alkylene oxides cyanide salts and cyanide solutions (forms... 

COPPER DINITRATE (3251-23-8) A strong oxidizer. Violent reaction with reducing agents, combustible materials, acetic anhydride, ethers, potassium ferrocyanide, finely divided tin. The aqueous solution is a medium-strong acid. Incompatible with bases, acetylene, ammonia, aliphatic amines, aikanolamines, amides, alkylene oxides, cyanides, epichlorohy-drin, esters, isocyanates, organic anhydrides, vinyl acetate. Attacks metals in the presence of moisture. 

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