Processing of gold ores with high sulfide minerals is problematic as they consume cyanide and reduce gold leaching. Optimization of gold leaching and cyanide consumption requires a methodology to estimate the amount of exposed cyanicides, their leaching kinetics, and speciation of cyanide complexes that consume the free cyanide and compete with gold. In this paper, a physico-chemical approach i...

electroplating industry wastewater (eiw) characterized by high chemical oxygen demand (cod) is a big source of water and air contamination with heavy metals. the formation of cyanide complex with heavy metals is responsible for its elevated cod. the concentration of heavy metals in eiw can be removed by the use of different precipitating agents (sulfide and hydroxide). but the major bottleneck ...

195pt and 1h nmr has been used to show that addition of chlorine and bromine to [pt(cn)4]2_ in presence of perchloric acid in water results in cyanide and water scrambling with formation of eleven complexes of the type [pt(cn)4-ncl(h2o)n+1](n-1)+ (n=0, 1, 2, 3, 4). addition of nbu4oh to this solution gives (nbu4)2[pt(cn)4cl(oh)]. nmr measurements in acetone also show cyanide and hydroxyl group ...

Standard solutions (at 10(-5) M levels) of Cu(I)- and Fe(II)-cyanide complexes were stabilized for at least 5 h using 0.5 mM cyanide solution (around pH 9) as a medium. Complexes of Cu(I)- and Fe(III)-cyanide also could be stabilized without any dissociation by adding 1 mM cyanide to an acetonitrile-water (18:82, v/v) mobile phase (pH 7.0) containing 10 mM tetra-n-propylammonium salt (TPA). Und...

195Pt and 1H NMR has been used to show that addition of chlorine and bromine to [Pt(CN)4]2_ in presence of perchloric acid in water results in cyanide and water scrambling with formation of eleven complexes of the type [Pt(CN)4-nCl(H2O)n+1](n-1)+ (n=0, 1, 2, 3, 4). Addition of NBu4OH ...

Cyanide is one of the most potent and toxic chemicals produced by industry. The jewelry industry of Córdoba (Spain) generates a wastewater (residue) that contains free cyanide, as well as large amounts of cyano-metal complexes. Cyanide is highly toxic to living systems because it forms very stable complexes with transition metals that are essential for protein function. In spite of its extreme ...

In this study, a rapid flow injection-flame atomic absorption spectrometry for cyanide detection was developed. Different AgX (where X is Cl(-), Br(-), I(-) and N(3)(-)) solid-phase reagents (SPR) were tested for indirect determination of cyanide. In a single-line FIA system, the cyanide was allowed to react with AgX SPR, which in turn changed Ag ions in AgX to silver cyanide complexes in a sod...

DeazaFMN-containing glycolate oxidase has been prepared and shown to catalyze the stereospecific transfer of the alpha-hydrogen from substrate to enzyme-bound deazaFMN. The reaction of sulfite, cyanide, and hydroxylamine with several deazaflavin-containing enzymes (glycolate oxidase, D-amino acid oxidase, glucose oxidase, N-methylglutamate synthetase) and free deazaFMN has been examined. All th...

The degradation capacity of a mixed culture of Agrobacterium tumefaciens SUTS 1 and Pseudomonas monteilii SUTS 2 for thiocyanate and metal cyanide, in the form of zinc and cadmium, has been determined. The growth of a mixed culture of SUTS 1 and SUTS 2 in cyanide complexes and the cyanide removal efficiency of a fixed-film bio-column system were studied. The results showed that the mixed cultur...

A near-stoichiometric amount of O2 was evolved as observed in the visible-light irradiation of an aqueous buffer (pH 8) containing [Ru(II) (2,2'-bipyridine)3 ] as a photosensitizer, Na2 S2 O8 as a sacrificial electron acceptor, and a heteropolynuclear cyanide complex as a water-oxidation catalyst. The heteropolynuclear cyanide complexes exhibited higher catalytic activity than a polynuclear cya...