Mercury arsenates Complex

Silver is the sixty-third most abnndant metal in Earth s crust the average concentration of silver in water is 0.5 ppb, in soil it is 10 ppb. It is fotmd naturally as native metal or in ores in which it is complexed with lead, copper, tellurium, mercury, arsenic, or antimony. Silver is fonnd mainly throughont the Americas, Japan, Anstraha, and central Europe. Extraction is by amalgamation and displacement (nsing mercnry), solution, or smelting methods. 

The solution should be free from the following, which either interfere or lead to an unsatisfactory deposit silver, mercury, bismuth, selenium, tellurium, arsenic, antimony, tin, molybdenum, gold and the platinum metals, thiocyanate, chloride, oxidising agents such as oxides of nitrogen, or excessive amounts of iron(III), nitrate or nitric acid. Chloride ion is avoided because Cu( I) is stabilised as a chloro-complex and remains in solution to be re-oxidised at the anode unless hydrazinium chloride is added as depolariser. 

Sulphuric acid is not recommended, because sulphate ions have a certain tendency to form complexes with iron(III) ions. Silver, copper, nickel, cobalt, titanium, uranium, molybdenum, mercury (>lgL-1), zinc, cadmium, and bismuth interfere. Mercury(I) and tin(II) salts, if present, should be converted into the mercury(II) and tin(IV) salts, otherwise the colour is destroyed. Phosphates, arsenates, fluorides, oxalates, and tartrates interfere, since they form fairly stable complexes with iron(III) ions the influence of phosphates and arsenates is reduced by the presence of a comparatively high concentration of acid. 

S.2.4.2.4. Complexes of Mercury(l) with Phosphorus-, Arsenic-and Antimony-Donor Ligands. 

The structural chemistry of some metal dithiocarbamates, i.e. systematics, coordination modes, crystal packing, and supramolecular self-assembly patterns of nickel, zinc, cadmium, mercury,363 organotin,364 and tellurium,365 366 complexes has been thoroughly analyzed and discussed in detail. Supramolecular self-assembly frequently occurs in non-transition heavier soft metal dithiocarbamates. Thus, lead(II),367 bismuth(III)368 zinc,369 cadmium,370 and (organo)mercury371 dithiocarbamates are associated through M- S secondary bonds, to form either dimeric supermolecules or chain-like supramolecular arrays. The arsenic(III)372 and antimony(III)373 dithiocarbamates are... 

Poisoning - Penicillamine also forms soluble complexes with iron, mercury, lead, and arsenic, which are readily excreted by the kidneys. The drug may be used to treat poisoning by these metals. 

Forrester Environmental Services, Inc., has developed a group of technologies for the stabilization of wastes containing heavy metals, such as lead, cadmium, arsenic, mercury, copper, zinc, and antimony. These technologies have been used in both industrial pollution prevention and remediation applications. One version of the technology involves the use of water-soluble phosphates and various complexing agents to produce a less soluble lead waste. This process results in a leach-resistant lead product. 

Besides the unintentional in-process adulteration of heavy metals, it is well established that Ayurvedic medicine and traditional Chinese medicine sometimes employ complex mixtures of plant, animal, and mineral substances, and it is not uncommon to find appreciable quantities of heavy metals such as lead, mercury, cadmium, arsenic, and gold in certain formulations (19,22,23). 

Insoluble starch xanthate (ISX) releases magnesium and takes up heavy metals. There are also a number of proprietary chemicals developed by various companies (e.g. Environmental Technology of Sanford, Florida) for removal of complexed copper, silver (from photographic process wastes), arsenic, nickel, lead, mercury, zinc, cadmium, barium, and other heavy metals. 

The cathodic deposition of arsenic at the dropping mercury cathode has been studied7 and appears to be complex both in acid and in alkaline solutions the polarisation curves do not show reversible shifts. From acid solutions the deposition of antimony or bismuth proceeds reversibly. 

A complex bromiodide of mercury and arsenic, AsHggBr Ig, presumably the arsenic salt of the acid HI(HgBr2)2, prepared by addition of hvdriodie acid to a benzene solution of mercuric bromide, has been obtained. ... 

N-(2,3-Dimercaptopropyl)phthalamidic acid (41, DMPA) has been shown to form relatively stable complexes with cadmium, zinc and mercury312. DMPA has also been shown to enhance faecal and urinary excretion of mercury in mice and arsenic in mice and rabbits. For the decorporation of arsenic, taken in as arsine, the administration of 3-(tolylthio)propane-l, 2-dithiol (42) has been proposed in the USSR313. ... 

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