Zirconium sulphates

Zireonyl Pyroarsenate, (Zr0)2As207.nH20, is obtained as a white precipitate when sodium monohydrogen orthoarsenate is added to a solution of zirconium sulphate.7 When dried at 110° C. the monohydrate, (Zr0)2As207.H20, remains. It is insoluble in water, but readily dissolves in hydrochloric acid. 

S04)3(H20)6 has been prepared during a study of the effects of bridging oxo-groups on the stability of zirconium sulphates prepared291 from oxosulphate solutions. 

Metal salts may be used in the treatment of wool. Flame methods for the determination of aluminium [185], barium, chromium, copper, mercury, strontium, tin, zinc [186] and zirconium [187] in wool have been published. Standard additions to wool cleaned by soaking and washing it with disodium EDTA (800 ml of 0.5 M for 30g wool with soaking for 3 days and double washing) was used as the calibration technique. This compensated for interferences from hydrochloric acid and amino-acids. The samples were equilibrated to a constant humidity for 24 h and then 0.3 g sealed with 5 ml of constant boiling point hydrochloric acid in a glass tube. The tubes were placed in an oven at 110UC for 20 h. The nitrous oxide/acetylene flame was used for the determination of aluminium and zirconium. Sulphate, phosphate, citrate and silicate have been found to interfere in the determination of titanium and zirconium in fire-proofed wool [188], These flame... 

Note A solution of zirconium sulphate or a zirconium salt solution containing excess sulphate ions does not give a precipitate with either ammonium oxalate or oxalic acid. This is due to the fact that the zirconium is present as the anion [Zr0(S04)2]2, hence sulphuric acid should be avoided in preparing solutions of zirconium salts. 

Saturated potassium sulphate solution white precipitate of K2[Zr0(S04)2], insoluble in excess of the reagent. When precipitation takes place in boiling solution, the resulting basic zirconium sulphate is insoluble in dilute hydrochloric acid (difference from thorium and cerium). No precipitate is obtained with sodium sulphate solution. 

Zirconium Molybdate, ZrfMoOjlj.ilHjO, is obtained by precipitation of ammonium paramolybdatc- solution with zirconium sulphate. ... 

The halogenates of zirconium, cerium, and thorium.—M. Weibuipsi claimed to have obtained needle-like crystals of hexahydrated zirconyl chlorate, Zr0(C10s)2-6H20, by the double decomposition of barium chlorate and zirconium sulphate, Zr(804)2, evaporation of the soln. over potassium hydroxide. 

Raman spectroscopic evidence has been obtained in support of the suggestion of over a decade ago that aqueous zirconium sulphate solutions do not contain a single preferred species stable over a range of composition. The equilibria shown in Scheme 2 were suggested to occur in sulphate solutions 0.1—0.4 mol 1 in zirconium. ... 

Solubility studies at different temperature of hydrated solid zirconium sulphates show the solids to be extremely soluble in water [07HAU], [41FAL] and... 

Falinski studied the solubility of hydrated zirconium sulphates and nitrates with differing concentrations of added sulphuric or nitric acid (see Figure A-2 and Figure A-3 respectively). Solid phases were analysed and show change in the solid phase composition with the concentration of added acid. Experiments were carried out at 25°C and 40°C. 

Figure A-8 Solubility data of solid zirconium sulphates with differing concentrations of added sulphuric acid.

A study by means of ion exchange yields thermodynamic data for zirconium sulphate complexes. The study confirmed the finding of [49CON/MCV] that no hydrolysis and polymerisation occur at log, [Zr] < - 4 in 2 M HCIO4. 

All of the members of the final review team contributed, if not text, then comments to all of the chapters of the book. Their primary responsibilities for the different sections/chapters were divided as follows. Paul Brown prepared the introduction, and the sections on elemental zirconium, the zirconyl ion, the gaseous zirconium oxides, zirconium hydride, the halogen compounds and complexes, the chalcogen compounds and complexes, the Group 15 compounds and complexes, zirconium carbides and silicates. He was assisted by Christian Ekberg in the interpretation of aqueous zirconium complexes in these sections. Some initial work was done by Ken Jackson on the zirconium sulphate, nitrate and phosphate compounds and complexes. Bernd Grambow was responsible for the drafting of the sections on zirconium hydrolysis, the ion and the section on crystalline and amorphous zirconium oxides. Enzo Curti drafted the section on the zirconium carbonates. 

A process has been developed by Ayres for the purification of zirconium, in which the various impurities are absorbed upon a cation-exchange resin. The zirconium itself is not absorbed as it is in the colloidal condition. This state is not difficult to achieve with, for example, zirconyl nitrate ZrO(NOs)2, since it is normally hydrolysed to the highly insoluble hydrated oxide in a neutral or near neutral solution. A zirconium ore is therefore broken in concentrated sulphuric acid and the soluble zirconium sulphate converted to the nitrate by suitable means and passed through a column of resin in the usual manner. Amberlite I.R.-100 has been used, in the hydrogen form. Impurities such as iron, beryllium and rare earth elements are absorbed completely, together with about 80 per cent of the titanium. The resin capacity for zirconium, however, is as low as 0-84 mmoles/100 cm of resin, and it is therefore recovered virtually completely in the pure column effluent. The very small amount of zirconium taken up by the resin is probably retained by a surface absorption process rather than true ion-exchange. The zirconium can be precipitated by alkah from the effluent as the hydrated oxide, in massive form, for conversion to other compounds and finally to metal. The resin is regenerated for further use by elution of the cation impurities with, for example, dilute sulphuric acid. 

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