Bulletin of the Society of Sea Water Science, Japan
Online ISSN : 2185-9213
Print ISSN : 0369-4550
ISSN-L : 0369-4550
Volume 24 , Issue 5
Showing 1-4 articles out of 4 articles from the selected issue
  • Hiroshi MUROTANI, Tadatoshi GOTO, Reiko AMEMIYA, Kazuo OGAWA, Akimasa ...
    1971 Volume 24 Issue 5 Pages 183-189
    Published: 1971
    Released: February 19, 2013
    Alkaline scale (calcium carbonate and magnesium hydroxide) and calcium sulfate scale are formed the evaporation process of sea water. Among these substances, the following reaction takesace: CaCO2(S) +MgSO4(L)+H2O (L) Mg (OH)2(S)+CaSO4(L)+CO2(G).
    The calcium carbonate scale is deposited by the decomposition of the calcium bicarbonate solution, nd this rate is proportional to the concentration of calcium and to the square of the bicarbonate oncentration.
    The magnesium hydroxide scale is formed by the above reaction toward the right side at highmperature, and this rate is proportional to the concentration of magnesium but is in inverseoportion to that of calcium.The calcium carbonate is crystallized by the above reaction toward the left side at the roommperature, where normal magnesium carbonate MgCO3·3H2O can be used instead of magnesiumydroxide and carbon dioxide. When normal carbonate is added to sea water, the reaction towarde left side takes place, and calcium component is removed as calcium carbonate precipitate.urthermore, the precipitation rate is influenced by the impurity of the additive. In this case, theddition of calcium carbonate as seed crystal indicates a positive effect in the following order: lcium carbonate monohydrate>aragonite>calcite.
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  • Masao MOTOYAMA, Minoru KADOTA, Shumpei OKA
    1971 Volume 24 Issue 5 Pages 189-196
    Published: 1971
    Released: February 19, 2013
    The authors investigated data related to the solubility of oceanic salts containing NaCl mainlym Chemical Abstracts published from 1940 to 1970. As the result, they made out four newbles; namely, three four-component systems, Na, Mg Cl, SO4-H2O, Na, K Cl, SO4-H2O and Na, Mg Cl-H2O and a five-component system, Na, K, Mg Cl, SO4-H2O. These tables represent thempositions of liquid phases and the kinds of solid phases on the mono-variant points saturatedth NaCl.
    The authors made out of these data polythermic equilibrium diagrams within the temperaturege of 50°C to 110°C, partially modifying the diagrams shown in the classical work of D'Ans.
    It was confirmed that the point of Y, at which four solid phases, namely, NaCl, loeweite (Na2SO4·MgSO4·5/2H2O), langbeinite (K2SO4·2MgSO4) and kieserite (MgSO4·H2O) coexist, existed evenat 110°C, and the composition of liquid phase was extrapolated, namely, Na2Cl2 23.9, K2Cl2 11.1, MgCl2 32.0 and MgSO4 11.5 moles per 1000 moles of H2O.
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  • Noboru OGATA
    1971 Volume 24 Issue 5 Pages 197-212
    Published: 1971
    Released: February 19, 2013
    Through the course of this fundamental study on the collection of uranium in sea water, the authorconducted an extensive improvement in the separating and determining methods of uranium in seawater. Also, he made various studies on the collecting methods of uranium in sea water, chieflyemploying the adsorption method with titanic acid which was one of the most effective methods.
    Chemical species of uranium in sea water were researched by the stability constants of suchcomponents of sea water as Na+, K+, Ca2+, Me+, SO42-, PO33-, HPO32-, CO32-, OH-, and UO22+. As the consequence, most of the dissolved uranium species were found to be UO2 (CO3) 34-.The adsorption mechanism of uranyl carbonate complex ion on titanic acid was presumed an anionexchange reaction. The adsorption of uranium was governed by the kind of titanic acid, thetemperature of sea water, the contacted volume of sea water and the concentration of uranium insea water.
    In the preparation of titanic acid, the adsorption capacity of titanic acid prepared in homogeneousand acidic solution proved to be larger than those prepared in non-homogeneous and neutral solution.Warm sea water was more preferrable because the amount of uranium adsorption indicated anextreme increase at a high temperature. The adsorption capacity was estimated by the distributioncoefficient multiplied by the concentration of uranium in sea water.
    Experimentally, the maximum value of the concentration of uranium in titanic acid amounted toU/Ti=1550μg/g, while the maximum adsorption capacity evaluated was U/Ti=4200μg/g. For thedesorption of uranium from titanic acid, the use use of hydrochloric acid was recommended as themost faultless method. In the conclusion of this study, the author presented some problems for future studies.
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  • Nagaaki TAKEMOTO
    1971 Volume 24 Issue 5 Pages 213-216
    Published: 1971
    Released: February 19, 2013
    In concentrating sea water for brine production by ion exchange membrane method, the permsele-tivity of each of the cations [Ti; {i cation in brine (N) /total cations in brine (N)} /{i cation in seawater (N) /total cations in sea water (N)}] was found to be expressed by linear equation of “thequivalent purity” of brine [PNa; Na (N) /total cations (N)] independent of membranes, units andonditions of electrodialysis. Thus, the concentration ratios of cations in brine [Pi; i cation (N) /totalations (N)] were given by the following equations:
    PMg=-0.8337 PNa+0.8057
    PCa=-0.1795 PNa+0.1797
    PK=0.01321 PNa+0.01462
    This regularity provided full suggestion as to the mechanism of permselectivity. For example, suggested the possibility of applying Stokes' law to the movement of ions within the membrane.In addition, three “purities” of brine generally used were termed here “the equivalent purity” PNa; mentioned above,“the weight purity” [PNaCl; NaCl (g/l) /total salts (g/l)] and “the convenienturity” [P°; {Cl-(Mg+Ca)} (N) /Cl (N)] of brine, respectively. These were correlated by theollowing equations:
    PNa=0.989P°-0.015 PNaCl=0.871P°+0.095
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