Distribution of Isomorphous Salts Between Aqueous and Solid Phases in Fractional Crystallization. Effect of Varying Concentration of Less Soluble Salt on Distribution

Murthy, A. S. Ananda; Mahadevappa, D. S.

doi:10.1021/i260042a009

Cited by 2 publications

(3 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In conclusion, it may be stated that from an approximate estimate of a in any industrial separation involving these systems the reported values of K and are quite adequate for theoretically computing the amount of Mg, Fe(II), or Ni salt crystallizing out of the ternary systems. A similar conclusion has been reached in our earlier work and eq 5 has been successfully employed for theoretically computing the less soluble salt crystallizing out of the ternary systems: (i) thallium alum-ammonium alum-water and potassium alum-ammonium alum-water (Ananda Murthy and Mahadevappa, 1969); (ii) nickel ammonium sulfate-magnesium ammonium sulfate-water and barium nitrate-lead nitrate-water (Ananda Murthy and Mahadevappa, 1970);…”

Section: Assumingsupporting

confidence: 76%

“…The resulting solution was kept in a thermostat at 30 °C for 6 h at the end of which crystals formed were separated from the mother liquor. Detailed experimental procedure has been described in the previous communications (Ananda Murthy and Mahadevappa, 1970).…”

mentioning

confidence: 99%

“…The correction factors (Ananda Murthy and Mahadevappa, 1970) range between 0.203-0.019 and 0.432-0.011, respectively, for the Mg-Cu salt system, 0.394-0.027 and 0.228-0.030, respectively, for Fe-Cu salt system, and 0.217-0.004 and 0.348-0.013, respectively, for the Ni-Cu salt system. Although the analysis of the aqueous phase is not required, it was carried out in all the experiments to check the results of analysis of the solid phase.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Distribution of isomorphous salts between aqueous and solid phases in ternary systems

Hariharan¹,

Anandamurthy²,

Mahadevappa³

1982

Ind. Eng. Chem. Proc. Des. Dev.

View full text Add to dashboard Cite

Distribution of isomorphous salts between aqueous and solid phases in ternary systems was studied at different concentrations of less soluble salt in the systems magnesium ammonium sulfate-copper ammonium sulfate-water, ferrous ammonium sulfate-copper ammonium sulfate-water, and nickel ammonium sulfate-copper ammonium sulate-water. Applicability of the theoretical equations developed by Doerner-Hoskins, Berthelot-Nernst, and Abu Elamayem for thg separations was investigated. Experimental results were explained by a proper choice of values for the parameters Kand m in Abu Elamayem's equation. These parameters characterize a given system over a wide range of concentrations and can be effectively used in predicting the amount of less soluble salt crystallizing out of the ternary system.Rapid crystallization of a pair of isomorphous salts from an aqueous solution results in a solid solution which changes in composition continuously. A study of the distribution of salts in the resulting system is of considerable theoretical and practical interest. Nonequilibrium states result when crystallization is carried out for short periods. Several equations have been proposed for studying the distribution of salts in ternary systems under equilibrium and nonequilibrium conditions. The Berthelot-Nernst law (Chlopin, 1925) may be written as x a -x -= Dc b -c where a and b are the total amounts of original salts, x and c are the amounts (grams) in the solid phase, (a -x ) and (b -c) are the amounts in the liquid phase, and D is the distribution constant. The logarithmic relation developed by Doerner and Hoskins (1925) for the coprecipitation of radium and barium chlorides with sulfuric acid is of the form d n In -= Xlne f where e and f are the initial amounts and d and n are the final amounts of radium and barium chlorides in solution. X is a constant. Hill et al. (1940) have given a semiempirical relation governing the distribution of a pair of isomorphous salts having a common ion, between the solid and aqueous phases -K R1 R," _ -(3)where R1 and R, are the mole ratios of salts A and B in the liquid and solid phases, respectively, m is an empirical constant, and K is the distribution constant.Abu Elamayem (1964) has worked out eq 4 and 5 for fractional crystallization of isomorphous salts in equilibrium and nonequilibrium systems, respectively y2w(K -1) -y[(w + a)(K -1) + 11 + Ka = 0 (4) r 1 1 where w = fraction by weight of original mixture separated as crystals, y = fraction by weight of less soluble salt in crystals, and a = fraction by weight of the less soluble salt in the original mixtures.MA and MB are the molecular weights of the two salts. K and m are constants employed in eq 3. As a special case when m = 1, eq 5 reduces to r 1 K \ a -wy -1Equations 1-4 are proposed for systems in equilibrium while eq 5 is applicable to a nonequilibrium system.The object of the present investigation was to study experimentally the distribution of a pair of isomorphous salts between aqueous and solid phases and examine the results from t...

show abstract

Section: Assumingsupporting

confidence: 76%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation