This report describes the results of experiments which were conducted following those on the adsorption of boron in boric acid solution and raw bittern to ferric hydroxide reported in the previous paper (This Journal 16, 264 (1963))
The sample, concentrated bittern used in this research, contained a larger quantity of sulfate ion. Studies were made to investigate the influence of the pH of solution, the temperature, the quantity of adsorbent and the time required, upon the adsorption of boron.
Ferric hydroxide prepared by the reaction of ferric chloride with milk of lime was stronger on the adsorption of boron in concentrated bittern than ferric hydroxide prepared by alkali solution of sodium hydroxide.

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On the basis of the best conditions obtained after examining the experimental results mentioned in our previous reports (This Journal 16, 264 (1963); 18, 105 (1964)), the boron contained in concentrated bittern and desulfurized bittern was adsorbed in ferric hydroxide that was prepared by the reaction of ferric chloride with alkali solution of sodium hydroxide or milk of lime.
The present investigation was conducted on the conditions under which boron adsorbed in ferric hydroxide was extracted with solution of sodium hydroxide or hydrochloric acid. The precipitates were washed with a proper quantity of water. The method using dilute solution of sodium hydroxide was the treatment in which the alkali solution over pH 11 was heated, and the method using dilute hydrochloric acid was the one in which the solution was heated at pH 3.5 to 4.5. Next, the elute of boron was obtained by the following method. The precipitate in which boron was adsorbed was dissolved in a proper quantity of dilute hydrochloric acid, and it was reprecipitated at pH 3.0 to 3.5 by adding dilute solution of sodium hydroxide.
It was found that the treatment using dilute hydrochloric acid was the best of all the methods used for the elution of boron to ferric hydroxide for the reason that the consumption of reagent was small.

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Magnesium stearate was prepared by heating stearic acid and magnesium hydroxide, The process of this reaction was discussed by means of differential thermal analysis, Magnesium hydroxide easily reacted upon with stearic acid under 100°, but neither magnesium oxide nor basic magnesium carbonate easily reacted upon with stearic acid. The mixture of magnesium stearate and stearic acid generally showed a complicated D. T. A. curve, and the figure of the curve varied according to mixing state. However, the mixture previously melted showed a characteristic curve, which was similar to that of reaction products, and it was possible to estimate the ratio of magnesium stearate to stearic acid in reaction products.

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The permselectivity coefficients of calcium ions against sodium ions (T^Ca_Na) across the hetero-geneous cation exchange membranes prepared from various types of ion exchange resins were determined by the electrodialysis in a five-compartment cell. The permselectivity coefficient T^Ca_Nashowed a max-imum value when X (the degree of cross-linking, percentage of divinylbenzene) was 4, in the case of the membranes prepared from Dowex 50W. Among the membranes containing such exchange groups as-SO₃H (from Amberlite IR-120),-COOH (from Amberlite IRC-50),-N (CH₂COOH)₂(from Dowex A-1) and-PO(OH)₂(from Duolite C-63), the order of T^Ca_Nawas;-SO₃H>-COOH>-N (CH₂COOH)₂>-PO(OH)₂, however, the latter three showed almost the same values of T^Ca_Na.

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The present investigation was conducted to explain the fact that the concentration rate of sulfate ion is generally less than that of chloride ion in the concentration of sea water by electrodialysis using ion exchange membranes. The electrophoretic mobility of chloride or sulfate ion in sodium chloride or sodium sulfate solution, respectively, and migration quantities of those ions in the mixed solution of sodium chloride and sodium sulfate in the anion exchange membranes were measured by applying a newly devised electrophoretic apparatus.
The following were the results obtained from the above experiments:
1) The mobility of each chloride and sulfate ion in the heterogeneous membrane was nearly equal, amounting to about 2.2×10-5cm2/v·sec. In the case of homogeneous membrane, on the other hand, there was 5.5×10-5for chloride ion and 4.7×10-5for sulfate ion.
These differences in mobilities between heterogeneous and homogeneous membranes were explained by the supposition that paths for ions in the former might be winding owing to the membrane structure, namely physical mixture of vinyl chloride and ion exchange resin.
2) As to the state of electromigration of chloride and sulfate ions in the membrane in the mixed solution of sodium chloride and sodium sulfate, the following facts were observed.
i) Under the low current density such as 1A/dm2, the separation factor of sulfate ion to chloride ion SSO4Clon the surface of membrane was 0.2-0.3, and this was nearly equal to the selectivity coefficient of sulfate ion to chloride ion KSO4Clunder the non-current state.
ii) Adsorbed ions on the surface of membrane were migrated into the membrane according to each mobility.
iii) Under the high current density such as 6A/dm2, the rate of sulfate ion adsorbed on the surface of membrane became higher, and then increased the ratio of migration quantity of sulfate ion to chloride ion in the membrane.

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In order to know the crystal structures, the compositions and the lattice constants of trichloromonofluoromethane (R-11), dichlorodifluoromethane (R-12), dichloromonofluoromethane (R-21) and monochlorodifluoromethane (R-22) hydrate, the X-ray diffraction diagrams of these hydrates were measured, and the following results were obtained:
1) The lattice constants of R-11, R-12, R-21 and R-22 hydrates were 17, 4, 17.3, 17.3 and 12.1 Å respectively.
2) It was evident that each of the R-11, R-12 and R-21 hydrates has the structure whichbe-longs to so-called structure type II and that the R-22 hydrate has the structure which belongs to so-called structure type I trans. Therefore, the former's theoretical composition was 17 H₂O mol/hydrating agent mol and the latter's one was 7 2/3 H₂O mol/hydrating agent mol.

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