Sulfato

Concentrated sulfuric acid (97 wt %) at 300—400°C has been used to solubili2e niobium from columbite and pyrochlore (18,19). The exothermic reaction is performed in iron or siUcon-iron cmcibles to yield a stable sulfato complex. The complex is filtered free of residue and is hydroly2ed by dilution with water and boiling to yield niobic acid which is removed by filtration as a white coUoidal precipitate. 

Ion Excha.nge, The recovery of uranium from leach solutions using ion exchange is a very important process (42). The uranium(VI) is selectively adsorbed to an anion-exchange resin as either the anionic sulfato or carbonato complexes. In carbonate solutions, the uranyl species is thought to be the tris carbonato complex, U02(C03) 3 [24646-13-7] and from sulfate solutions the anion is likely to be U02(S0 , where nis ) [56959-61-6] or 2 [27190-85-8], The uranium is eluted from the resin with a salt or acid solution of 1 AfMCl or MNO (M = H", Na", The sulfate solution is... 

One of the few strong acids is tetrafhydrogen sulfato)boric acid HB(HS04)4 solutions of this can be obtained by dissolving boric acid in oleum ... 

The separation of basic precipitates of hydrous Th02 from the lanthanides in monazite sands has been outlined in Fig. 30.1 (p. 1230). These precipitates may then be dissolved in nitric acid and the thorium extracted into tributyl phosphate, (Bu"0)3PO, diluted with kerosene. In the case of Canadian production, the uranium ores are leached with sulfuric acid and the anionic sulfato complex of U preferentially absorbed onto an anion exchange resin. The Th is separated from Fe, A1 and other metals in the liquor by solvent extraction. 

Chemical Name Hexadeca-)U-hydroxytetracosahydroxyl/Ug-l 1,3,4,6-tetra-O-suifo-/3-D-fructo-furanosyl-a-D-glucopyranoside tetrakisihydrogen sulfato)(8-)] ] hexadecaaluminum... 

B-C bonds, 3, 97 B-N bonds, 3, 97 B-O bonds, 3,94 B-P bonds, 3, 97 B-Si bonds, 3, 97 oxo acid anion complexes, 3, 96 Borates, alkoxo-, 3, 94 Borates, amidotrihydro-, 3,92 Borates, aryloxo-, 3, 94 Borates, carboxylato-, 3,96 Borates, catechol, 3,95 Borates, chlorosulfato-, 3,97 Borates, dicarboxylato-, 3,96 Borates, dipyrazol-l-yl-, 3, 92 Borates, halogeno-, 3,92 Borates, halogenohydro-, 3,90 Borates, hydro-, 3,90 Borates, hydrohydroxo-, 3,90 Borates, hydropyrazol-l-yl-, 3, 92 Borates, hydroxo-, 3,94 Borates, hydroxycarboxylato-, 3,96 Borates, inositol, 3, 95 Borates, monoalkyl-, 3, 92 Borates, monophosphido-, 3, 92 Borates, peroxohydroxo-, 3, 94 Borates, polyol, 3, 95 Borates, pyrrol-l-yl-, 3, 92 Borates, sulfato-, 3, 97 Borates, tetrabromo-, 3, 92 Borates, tetrachloro-, 3, 92 Borates, tetrafluoro-, 3, 92 minerals, 6, 847 Borates, tetrahalogeno-mixed, 3, 93 nB NMR, 3, 92 Borates, tetraiodo-, 3, 92 Borates, tetranitrato-, 3, 96 Borates, tetraperchlorato-, 3, 97 Borates, tripyrazol-l-yl-, 3, 92 Borax, 3,101 Borazines... 

U1 "1" (16), and Np1 "1" (17) (Table IV). Only in the thorium system have stability constants been determined as a function of acidity. Zebroski et al., (12) found that the 1 2 complex had the form TMSOi, at 0.5 M and 1.0 M acidity but suggested a contribution from the monoprotonated, bis-sulfato complex in 2 M acid. However, Zielen (9) found no evidence for such a species. The Kj/K2 ratio found in the latter study (n.8) compares favorably with the Am(III)-S0 data of DeCarvalho and Choppin (10)... 

Analysis of sulfonic acid species in sulfonated olefins. Kupfer and Kuenzler [108] reported the determination of acid species following partition between a 6.5% hydrochloric acid solution in 40% ethanol and a 1 1 (v/v) propan-2-ol-hexane mixture. The organic fraction contains alkenesulfonic and hydroxy-alkanesulfonic acids and the aqueous phase disulfonic acids and sulfato-sulfonates. The monosulfonic acids were converted to methyl esters and separated by column chromatography. To determine sulfatosulfonates the aqueous fraction was hydrolyzed and then partitioned and chromatographed. The separation is controlled using IR spectroscopy. 

The sulfate ion, well known as a monodentate and simple bidentate ligand, has been observed also as a bridging ligand, as exemplified in [(en)2Co(OS(O2)O)2Co(en)2]2+.10°3 The c/.v-bisf/x-sulfato) bridge undergoes hydrolysis to c -[Co(en)2(OS03)(OH2)]+ in acidic solution, hydrolyzing further with loss of coordinated sulfate in aqueous base to the dihydroxo complex. 

With diammonium ions [H3N(CH2) NH3]2+ (2 < n < 6) as counterions, several linear and layered polymeric Cd sulfates are generated. In the chain anion oo1[CdCl4/2(S04)2/2]2 ( = 2), octahedral units are linked by both /r-chloro and /r-sulfato bridges a similar structural situation is met in the compounds with oo1[CdX4/2(S04)2/2]2 anions (X = C1, Br n = 6). A layered structure of the anion oo2[Cd2(H20)2(S04)3T (n = 3) is achieved by linking two different octahedral CdOfi units by S04 bridges exclusively. 0... 

A simplified series of reactions between a hafnium salt and sulfuric acid is given in Fig. 4.3. The reactions showcase important facets of thin-film synthesis (but do not address the precise identities of intermediates or complexities of aqueous hafnium chemistry.) In the first step, a hafnium oxide chloride crystal hydrate is dissolved in water to disperse small hafnium-hydroxo molecular clusters. Sulfato ligands are subsequently added in the form of sulfuric acid. Since sulfato binds more strongly than chloro, hafnium-hydroxo-sulfato aqueous species are created. Under mild heating, these species readily poly-... 

Sulfate de Dimethyle Sulfate de Methyle Sulfate Dimethylique Sulfato de Dimetilo Sulfinyl Chloride Sulfinyl Dichloride Sulfocarbonic Anhydride Sulfonal... 

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