[en] Coprecipitation has been studied of beryllium with hydroxides of metals of 2-4,6, and 8 groups of the periodic Table (Zn,Cd,Al,Ga,In,Sc,Y,Th, etc.). It has been shown that the main characteristics of coprecipitation of beryllium (pH of the onset and maximum coprecipitation,pH of the beginning and end of desorption) are affected by the nature of the collectors. It has been stated that sorption ability of the metal hydroxides being studied correlates in respect of beryllium with pH value of the onset of precipitation

[en] Studied is the coprecipitation of different quantities of indium (from 1μg to 7.2 mg) with the hydroxides of Sn(4), Fe(3), Th, Be, Cd and Mg depending on solution pH. The coprecipitation of a given element is shown to be described by the same effects which have been previously found in studying coprecipitation of other hydrolizing elements such as berillium, tin(4), iron(3), chromium(3), and cadmium. Basing on the acid-basic nature of the sorbent-sorbate reaction the study finds universal relationships for the above hydrolizing elements with metal hydroxides

[en] Coprecipitation of beryllium with hydroxides of amphoteric metals (Zn, Al, Ga, Sn⁴, Pb², Te⁴, Cr³) has been studied upon neutralization of their alkali solutions depending on pH of the solution. Specific features of such coprecipitation have been revealed and compared with a capture of beryllium under conditions of hydrolytic precipitation of the corresponding collectors from acid solutions. In particular, the formation of the stable product of acid-basic interaction has been observed. The product is formed by beryllium with chromium (3) and tin (4) and can be decomposed only upon complete dissolution of the collector in the excess of the acid. The results obtained allow to conclude that the character of coprecipitation of beryllium with metal hydroxides upon neutralization of both acid and alkaline solutions is determined by different acid-basic properties of the microcomponent and the collector

[en] Studied is the coprecipitation of different cadmium quantities (from 10 μg to 7.05 mg) with Snsup((4)), Fesup((3)), Th, Be and Mg hydroxides depending on solution pH. The pH value of the initial coprecipitation of the microcomponent with the hydroxides of Snsup((4)), Fe((3)), Tn, and Be, was shown to be coincident with the disappearence from the solution of a positively-charged hydroxocomplex of relevant element. It was also shown that the capture of large cadmium quantities (500 μg, 7.05 mg) by tin(4) hydroxide was greatly enhanced when hydrolized microcomponent elements emerged in the solution at pH>5.2. The coincidence of the pH values of the initial cadmium coprecipitation with magnesium hydroxide with the pH initial precipitation value is caused by the fact that for cadmium at pH>8 it is typical to form its principle coprecipitate species, the neutral hydroxocomplex Cd(OH)₂⁰, in the solution. An explanation is offered for the controversy existing in literary data. Specifically, it is shown that the competing effects of the macroquantities of indium and aluminium for the capture of cadmium microquantities by iron(3) hydroxide are caused by the presence in the solution of their positively-charged hydroxocomplexes

No abstract available

[en] Sorption of thorium microquantities by hydroxides of bi-, tri-, and tetravalent metals in coprecipitation conditions is investigated. It is shown that sorptive ability of of metal hydroxides relative to thorium decreases with increase of pH value of precipitation beginning, that is with decrease of acidic properties of the collectors in a row Sn(1.1)>Ti(1.1)>Zr(0.8)>Fe(2.0)>Ga(2.8)>In(3.4)>Al(4.0)>Cr(5.)>Be(6.0). It is determined that thorium sorption by metal hydroxides takes place as a result of acid-base interaction between micro- and macrocomponents through heterohydroxocomplex formation type

[en] Element atom electronegativities are used when evaluating the relative ability of oxo anions to interact with metal hydroxides M(OH)₂ with the production of M₂(OH)₃X composition basic salts, where M=Mg, Cd, Co(2), Ni(2), Zn and Cu(2); X-oxo anion. The ability of basic salts to resist electrolytic and hydrolytic dissociation in aqueous solutions, which is considerably defined by the character of oxo anion chemical bond in the composition of basic salts and protonated forms, is taken for evaluation. Basic salt resistance to electrolytic and hydrolytic dissociation in characterized by opposite dependences on the values of average oxo anion electronegativity

[en] The present report concerns the vibrational spectra and assignments of Ln(OH)₃ (Ln = La, Nd, Tm, Eu, Gd, Tb, Dy, and Y). (author)

[en] A study was made on sorption of uranium(6) small quantities by hydroxides of some bivalent metals during coprecipitation in the absence of carbonate ions, as well as by cryogranulated hydroxides of bivalent metals and mixed hydroxides of different-valent metals from weakly carbonate solutions depending on pH. It is shown that sorption ability of hydroxides of bivalent metals decreases with respect to uranium(6) with growth of pH of the beginning of their precipitation, that is with decrease of acidic properties of collector in Be>Zn>Cd>Sr series. The same dependence preserves during sorption by cryogranulated hydroxides from weakly carbonate solutions at pH 9.5-10.0 in Zn?>Cu>Pb>Ni>Co series. Uranium(6) sorption is presented as a result of acid-base interaction between micro- and macrocomponents according to the type of formation of heterohydroxocomplexes. 9 refs., 6 figs

[en] Boron sorption with metal hydroxides, prepared in the form of granulated material, has been realized when using the regime of repeating cycles of sorption and desorption. Bivalent metal hydroxides with the structure of brucite (Mg, Mn, Fe, Co, Ni and Cd) adsorb B₄O₇^2- ions from solutions due to the exchange with OH^- ions. The adsorption depends on the value of hydroxide basicity constant. Using Ni(OH)₂ as an example, it is shown that the sorption products present basic salt of nonstoichiometric composition with the structure of nickel hydroxinitrate type. Desorption of boron ions is exercised with the NaOH solution