Claus’ blues

A spectroscopic study of Claus blue, with comparisons to the much better characterized (180) ion [Rh2(0H)2(H20)n(/u,-02)]3+, was thus undertaken (181). By the use of UV-vis, ESR, and IR/Raman spectroscopies, as well as magnetic susceptibility measurements and voltamme-tric studies, it was determined that Claus blue solutions actually contain superoxo-dirhodium complexes, and not RhO2- ions. The su-peroxo bridge does not, however, derive from dioxygen, but from oxidation of coordinated hydroxide. Finally, Claus blue solutions were demonstrated to be good starting materials for the preparation of superoxo-dirhodium carboxylate complexes, which could be isolated and characterized. 

Excess oils and hydrocarbons in the sulfur plant feed can readily darken the sulfur, minimizing its sales value. Ammonia can cause fouling of the Claus catalyst beds. Cyanides have a tendency to polymerize, causing significant problems with the formation of Prussian blue. Organic forms of sulfur are not so readily reacted in low-temperature Claus beds and may cause problems in achieving the desired sulfur plant efficiency. Addi-... 

Tannio acid seems to form combinations with solutions of sterch, giving a greyish-white flaky precipitate, which becomes transparent in the heat, but reappears in the usual form as the liquid cools. This acid decolors the blue iodide of starch, and when present in sufficient quantity it prevents the entire decomposition of focula by means of diastase. The reaction contributes in part to the formation of artificial leather on Claus-SBN s principle, as already detailed in this work. 

Some forty years before the discovery7 of ruthenium by Claus, it had been observed by Vauquelin that an azure blue colour is obtained by the action of zinc on certain solutions. This was attributed to the presence of osmium, but is now known to be a characteristic reaction for trivalent ruthenium. A similar colour is obtained by the action of hydrogen sulphide upon ruthenium trichloride, and wTas attributed by Claus and Joly 6 to reduction to the dichloride. This view is supported by Howe,7 who, however, has not succeeded in isolating the salt, but has obtained a derivative to which he gives the formula ... 

Sodium Rhodate, Na2Rh04.—If the gases evolved by the action of hydrochloric acid upon potassium chlorate are passed into a solution of a rhodium salt rendered alkaline with sodium hydroxide, the liquid assumes a yellowish red, then a red colour, and finally a slight green precipitate forms. The latter dissolves, yielding a solution of blue colour known as Claus s Blue, and containing sodium rhodate. 

It has long been known (Claus, 1846) that reduction (e.g. Zn, H2 with Pt catalyst) of some ruthenium salts gives a blue solution, which on treatment with HCl or oxidation turns green. Various claims have been made for... 

There are other verbally exuberant qualities in Gogol s style his elaborate sentence structure, analyzed in detail by Bely, who speaks of Gogol s exploded sentence, scattered about in splinters of subordinate clauses and the devices which Pereverzev in his chapter on Gogol s style calls amplification and self-interruption. The best example of the use of amplification is the Tale of Captain Kopey-kin, a good early illustration of what later came to be called skaz. The narrative manner of the postmaster who tells this story is announced in chapter 8 the auxiliary expressions he uses to stretch out and amplify the tale occupy roughly half of the text, and if we were to blue-pencil the extraneous matter and the repetitions, the story could probably be cut down to about one-third of its length. 

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