Ferric dithionate

Ferric dithionate has not been isolated, as its solution decomposes yielding ferric sulphate, ferrous dithionate, sulphurous and sulphuric acids. 

In the case of the reduction of ferric salts by sulphur dioxide it has been suggested 9 that the reduction most probably proceeds in stages, a red ferric ferrisulphite, Fe[Fe(S03)3], being first formed, which on warming yields the ferrous salt and the dithionate, thus ... 

Dithionic Acid, H2S2O0, is obtained only in aqueous solution. If sulphur dioxide is passed into an aqueous suspension of ferric hydroxide at 0° C., a red solution of ferric sulphite is first produced, which then changes to a pale green solution of ferrous sulphite and ferrous dithionate 4... 

Reduction of Ferric Chelates by HSO3 and Formation of Dithionate. FeJ+(EDTA) is reduced by HSO3, producing dithionate and a small amount of S0/2 (24). The rate of reduction of Fe +(EDTA) is first order in [HSO3] and [Fe +(EDTA)], and inversely first order in [Fe2+(EDTA)]. 

The improvement over the existing Japanese processes can be made by developing a more efficient ferrous chelate such that it can provide better absorption efficiency for NO, faster reaction rates between NO and S02> and better stability for the ferrous chelate toward oxidation, compared to Fe +(EDTA) or Fe +(NTA) employed in Japanese processes. The development of an efficient and cost-effective method for the reduction of ferric chelate to ferrous chelate without producing dithionate ions could make the process attractive. In addition to these areas, the study of several alternative approaches and novel ideas could develop into a much more efficient and cost-effective scrubber system employing metal chelate additives. 

Ferrous dithionate, FeS206, is readily obtained by double decomposition of solutions of the barium salt and ferrous sulphate. The dithionate is also formed by dissolving ferric hydroxide in sulphurous... 

On passing sulphur dioxide into cold solutions of ferric sulphate, ferrous dithionate is formed.3 With a 2 per cent, solution of ferric sulphate, 80 per cent, of the sulphate is converted into dithionate at 0° C., but this amount diminishes as the temperature rises, none being formed at 95 ° C. The equilibrium may be represented by the equation —... 

Pyrazolin-5-ones form complexes with both inorganic and organic compounds much more readily than do the 2-pyrazolin-5-ones. The most extensive series of complexes is that formed with a variety of metallic salts. Antipyrine (2,3-dimethyl-l-phenyl-3-pyrazolin-5-one) forms a series of complexes with salts of divalent, trivalent and tetra-valent metals. Two molecules of antipyrine form a complex with one molecule of copper, cadmium, cobalt and zinc salts.266,866,1116 Complexes prepared from metallic nitrates are usually hydrated.1322 There also exists a series of complexes in which three molecules of antipyrine form a complex with one or two molecules of metallic salts. Such complexes form with two molecules of simple ferric salts272 or with one of complex iron cyanides.608 Nitrates of thorium, lanthanum, cerium and samarium also give such complexes.841 This ratio also occurs in some antipyrine complexes with cadmium and zinc thiocyanate.266 A number of salts of rare earths and iron which have complex anions such as thiosulfate, thiocyanate, dithionic acid and complex iron cyanides form complexes in which six molecules of antipyrine are present.405,408 608,841,950 Stannic chloride forms salts containing three or four molecules of antipyrine and hydrochloric acid.46... 

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