The dispersibility of nonmagnetic and magnetic ferric oxides adsorbing polymer molecules (copoly(vinyl acetate-vinyl chloride-maleic acid) and copoly(vinyl acetate-vinyl chloride-vinyl alcohol)) in polar organic media (2-butanone) was investigate from the particle distribution data and the potential energy between the particles. In order to calculate the potential energy, the octahedral and needlelike particles used in this study were assumed to be spherical and cylindrical, respectively. It was found that the order of the median diameter obtained from the particle distribution histogram was the same as the order of the dispersion stability reported in the previous paper.
The strong magnetic attractive force operated over a long range of distance for the octahedral particles due to their large volume and magnetism, while the weak magnetic attractive force operated f or the needlelike particles due to their comparatively small volume. It was shown from the calculation of the potential energy that the magnetic attractive force became weaker, provided that the volume of the octahedral particles were lowered and it became to be as small as that of the needlelike particle. It was concluded from the results that the strength of the magnetization and the volume of the particle were main factors for flocculation of the magnetic particles. The new equation introduced in this paper for the potential energy of the needlelike particles was qualitatively consistent with the experimental results.

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Rheological properties of hydrogels of poly (vinyl alcohol) (PVA) (frozen at -15°C, and melted every 24 h) were examined by vibration, stress relaxation and simple extension measurements. The freezing time was chosen as 6, 12, 24, 48, 72, and 96 h. The degree of polymerization and the degree of saponification of the PVA were about 2400 and 99.6 ±0.3mol%, respectively. Stress relaxation was measured in the temperature range from 25°C to 65°C up to 10 h. The dynamic Young's modulus, E', and the mechanical loss tangent, tan o, were obtained at 2.5 Hz by longitudinal vibrations of a cylindrical gel. The weight and E'of the gels frozen for more than 72 h did not decrease even after a month of immersion in distilled water. The tan o decreased with increasing freezing time. The course of extension of the gels was photographed. From these results, the effect of freezing time on E' was explained through the formation of microcrystalline within the gels.

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Seventeen photopolymers have been synthesized by esterifying acrylic - acid and/or a dicarboxylic acid with 1, 2-polybutadiene modified by adding 2-mercaptoethanol, and their photosensitivities were studied. The dicarboxylic acids used in this study involved phthalic acid, maleic acid, itaconic acid, trimellitic acid, tetrahydrophthalic acid and 5-norbornene-2, 3dicarboxylic acid. Among the photopolymers synthesized, those, in which more than 1/3 mol%of hydroxyl groups in a molecule of the parent polymer were esterified with dicarboxylic acid, were soluble in a weak alkaline water such as 1 wt% aqueous solution of sodium hydroxide.
The polymers, with the aid of photoinitiator were insolubilized in the solvents by irradiating the ultraviolet light and showed the sensitivities between 3.0 mJ/cm2 when sensitized with the bimolecular type photoinitiator, 2, 4-diisopropylthioxanthone/isopentyl p-dimethylaminobenzoate. The minimum quantity of exposure energy required for gelation of the polymer was proportional to the square root of the initiator concentration when the concentration was low. It was found from the measurement of spectral sensitivity that the minimum quantity of the exposure energy f or the gelation was clearly related to the molarextinction coefficient of the initiator molecule.

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The polarographic behaviors of oxobis(2, 4-pentanedionato)vanadium(IV) ([VO(acac)₂]) have been studied by tast d. c. polarography and pulse polarography in acetate buffer solutions. The complex features obtained usually for polarograms of [VO(acac)₂] were successfully interpreted in terms of auto-inhibition with electrolytic products. Well-defined two separate waves of equal height were obtained when the effect of auto-inhibition was negligibly small. [VO(acac)₂] is reduced to V^III at -0.812 V vs. SCE and then reduced to V^II at -1.072 V vs. SCE. The reduction of [VO(acac)₂] to V is more feasible in aqueous solutions than in acetonitrile solutions. The characteristics of polarogaphic reduction waves were discussed.

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The behavior of a silver-silver oxide electrode in KOH solution containing a small amount of manganese(II) chloride and manganese(IV) oxide was examined by potentiostati c and galvanostatic methods as well as an observation under a scanning electron microscope.
The following results were obtained.1) The charge and discharge capacity of the electrode measured by a galvanostatic method was obviously increased by the addition of manganese(II)chloride and manganese(IV) oxide.2) The coulombic areas under all the peaks in c rams increased with the addition of the chloride. On the other hand, the yfcirlisct voltammog oxidation peak and the second reduction peak increased with the addition of the oxide. The electrode capacity determined by charge-discharge curves and current-potential curves inc reased i n the presence of the chloride and the oxide. Consequently, manganese(II) chloride 1×10^-3mol/l (4.7 mol/l KOH) solution was more effective than any other solutions.3) The active materials of the electrode grew into a big crystal in the absence of the chloride electrode with added chloride the formation of_a fine crystal was obserbed by electr, o mwihcriloes cionp eth. eThe increase in electrode capacity caused by the addition of the chloride seems to be due to the formation of such finely crystalline substance. It has been concluded that the behavior of the elcctrode can be explained by the adsorption and electrolytic deposition-dissolution of ionized particles produced from the added manganesean chloride during charge and discharge cycles.

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Stability of sodium bromite (NaBrO₂) aqueous solution was studied by means of chemical and UV spectral analyses. NaBrO₂ aq. soln. hardly decomposed in the presence of Br^-, Cl^-(by-products of NaBrO₂) and BrO₂^- (decomposition product of NaBrO₂) at.70°C and pH 13. However, NaBrO₂ aq. soln. gradually decomposed by addition of metal ions such as Fe⁺, Ni²⁺, Cu²⁺ and Al³⁺.
The X-ray diffraction study and chemical analysis of decomposition products of NaBrO₂ by copper ions showed existence of CuO, CuBr₂, Br₂O₂ and hence following reactions are suggested.
It was considered that these reactions simultaneously proceeded for CuBr2 was soluble and CuO was slightly soluble in strong alkaline soln. This paper has also revealed that pure NaBrO₂ aq. soln. at pH 13 is stable at 95°C for 6 h and could be condensed to crystallize NaBr0₂·3 H₂O.

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Thermal decomposition of tricalcium imidobis(sulfate)-water (1/6) (TCIS?6 aq) over the temperature range 20-500°C was investigated by using DTA and TG together with X-ray powder diffraction method and paper chromatography. Also, the solubility for the system Ca(SO₃)₂NHCa(OH)₂-H₂O at 30°C was studied to clarify the area of formation of TCIS·6 aq in the system.
The thermal decomposition of TCIS·6 aq progressed in three stages. In the first stage, 2 mol of the water of crystallization were liberated at about 90°C and in the second stage 4 mol of the residual water at about 207°C. In the last stage, the following decomposition began at about 250°C,
Ca₂(SO₃)4N₂Ca→3CaSO₄+N2↑ +S↑
and the reaction was practically compleated at 400-500°C. The powder X-ray diffraction data of TCIS?6 aq was presented. The solubility of TCIS in water was as follows; 0°C: 41.0g/100 g H₂O, 30°C: 23.0 g/100 g H₂O, 50°C: 15.4 g/100 g H₂O, 70°C: 10.1 g/100 g H₂O. The phase diagram for the aqueous system indicated the stable area of Ca(SO₃)₂NH.4H₂O snd Ca₂(SO₃)N₂Ca·6H₂O as the solid phase together with the feature that the solubilities of both salts being diminished remarkably on addition of a small amount of calcium hydroxide.

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The decomposition of Lepidolite was studied under alkaline hydrothermal conditions of 150-350°C and up to 20Mpa. The extraction ratios of Li₂O, K₂O, Al₂O₃ and SiO₂ were 99, 95, 23 and 74%, respectively, by using 7 mol. dm^-3 NaOH solution at 350°C. The region of formation of alumminosilicate residue was determined in terms of temperatures and alkaline conditions. Analcime was formed at 200-350°C and up to 3mol·dm^-3 NaOH concentration, Natrodavyne (low temperature form) at 150-250°C and above 3mol·dm^-3 NaOH concentration, and Cancrinite and Na-zeolite at 250-350°C and above 3mol·dm^-3 NaOH concentration.

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Following to our previous study that recently prepared oxamido(oa), oxamato(om), and oxalato(ox) bridged binuclear copper(II) complexes showed interesting magnetic properties, corresponding nickel(II) complexes(Table 2) were prepared and the dependence of physical properties of the complexes upon L(Table 1) and the bridging groups, oa, om, and ox were studied. The nickel( II ) complexes were characterized by the infrared and electronic spectra, and magnetic moments(Table 3). The complexes have the skeletal structures as shown in Fig.1, and magnetic moments are slightly less than those of usual mononuclear nickel(10)high-spin complexes at room temperature. The values decrease, in general, in the order of the bridging group, ox>om>oa, but no clear trend was found for the ligands L. To see the magnetic properties in detail, the complexes [Ni₂(bridge)(dpa)₄](NO₃)₂·nH₂O(dpa=di-2-pyridylamine)were subjected to the measurements of magnetic susceptibilities at various temperatures. The results are explained in terms of a binuclear nickel(10) complex having antiferromagnetic interaction and the interactions decrease in the order of the bridging group, oa(J/k=-29 K)>om(-26)>ox(-22).

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The flow rate and flow direction of ground water were determined on the basis of the intervals of sampling dates which indicated maximum correlation number between two wells. The concentrations of water soluble components (Cl, Na, Ca, Mg, etc. ) were analyzed for three wells sharing common aquifer. The correlation number between the ground water samples was determined by the concentration ratio matching method which provides correlations among chemical components. As for all intervals of sampling dates, the variation of correlation number between two wells was obtained. The variation showed a flow pattern of ground water and the maximum correlation number was found at some intervals for each combination of two wells (Figs.3, 4, 5). It was assumed that the interval corresponds to the time that a flowing face of a whole flow moved from one well to another. The whole flow rate and flow direction were determined by means of the combination of two intervals. The combination number of the intervals among three wells is three. These three whole flow rates and flow directions agreed with each other.

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A highly sensitive and simple method is developed for the determination of ppt (pg·cm^-3)levels of cobalt in water by adapting flow injection and a catalytic photometric detection. The oxidation of Tiron (4, 5-dihydroxy-1, 3-benzenedisulfonic acid) by hydrogen peroxide is catalyzed by small amount of cobalt ion. The product has maximum absorbance at 440 nm. The sample volume can be increased as much as cm3 order by setting up a cation exchange resin column between a sample injection valve and a mixer. Under the conditions of carrier solution: O.15mol·dm^-3 NaCl-0.015 mol·dm^-3 sodium tartrate mixed solution (1.0 cm^-3·min^-1), Tiron solution: 0.01 mol· dm^-3 (0.2 cm³·min^-1), H₂O₂ solution: 0, 01 mol·dm^-3(0.2 cm³·min-1), reaction coil: 5 m long and 1 mm i. d., reaction temperature: 40°C and the sample: 2.0 cm³, a linear relation was found between the peak height and the cobalt concentration in the range of 5-200 ppt. The detection limit and the determination limit were 2 pg and 5 ppt, respectively. The relative standard deviation was 7.8% (n=5) at 5 ppt. Coexistence of Fe(II), Cu(II), Ni(II), Mn(II), Cr(II), Ca( II) and Mg( II) of 200-fold against 50 ppt cobalt ion not interfere with the determination.

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The ¹³C-NMR chemical shifts of various substituted anthrones were measured, and the absorption peaks of respective carbons were assigned according to the chemical shifts calculated by using empirical additivity rule. The observed chemical shifts for the anthrones are discussed in relation to the charge densities calculated by CNDO/2 method. The chemical shifts of C-1, C-2, C-3, C-4, C-9 a and C-4 a carbons are correlated with the chemical shifts of monosubstituted benzenes. A multiple correlation of the chemical shifts with Swain, Lupton and Schaefer's substitutent constants are discussed. The three types of the correlations can be used for predicting the chemical shifts of anthrones.

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Present paper deals with the construction of a second harmonic A. C. polarograph, the assessment of its performance, and its analytical application. Although the foundamental harmonic A. C. polarographs have been used so widely in analytical chemistry, the second harmonic A. C. polarographs have not been so widely used.
The block diagram of the apparatus is shown in Fig.1. The A. C. frequencies used were 10-300 Hz. The total current of the second harmonics was measured through a tuned ampliher. The base current of the second harmonic A. C. polarogram for Cd(II) was much smaller than that of the fundamental A. C. polarogram. In the application to the stripping analysis of nickel(II) ion, employing the preconcentration by the adsorption of nickel(II)-2, 2'-bipyridine complex, the second harmonic A. C. polarography was shown to be much more sensitive compared to D. C. and fundamental harmonic A. C. polarogrpahy (Fig.2). The sensitivity of the method was about 10 times higher than in the previous result. After 30 min preconcentration, 10^-8molf/ nickel(II) ion was detected. The standard deviation of 5 samples was 2.61%. Only cobalt(II) ion interfered with the method.

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Hydrophilic gels were prepared by the suspension copolymerization of 2-hydroxyethyl acrylate (PHEA) with ethylene dimethacrylate in an aqueous solution of sodium sulfate using aliphatic alcohols as diluents. The permeability was determined by the elution of water soluble materials, such as poly(oxyethylene), on a column packed with the gels. Excluded molecular weights increased gradually with increasing the amount of the diluent. ' An amount of hydrophobic materials, which were adsorbed on the gels during elution, was less than that on a copolymer of 2-hydroxyethyl methacrylate (PHEMA) and ethylene dimethacrylate. On the other hand, the pressure-resistance of the gel, the property of the gel by which it opposed and limited the pressure of the passage, was inferior to that of the latter copolymer.

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The extractions of titanium(IV) and molybdenum (VI) from aqueous oxalic acid solutions with trioctylamine (R₃N, TOA) in xylene have been studied. The stoichiometry of the extracted species has been investigated by three different methods. The composition of both extracted species can be estimated as follows: R₃N: Metal ion: Oxalate=2:1:2. The dependences of the distribution ratios of the oxalato complexes on the pH and the TOA concentration are also investigated. These results suggest that the oxalato complexes combine with two mole cules of R₃NH⁺. The extracted species isolated are subjected to infrared (IR) and thermal analyses to estimate their compositions. Gel permeation chromatography (GPC) of the isolated species is also carried out to determine their molecular weights. In the IR spectrum of the titanium(IV) species, the absorption due to the OH strectching vibration, which indicates the presence of bound water in it, occurs at 3450 cm^-1. The results of the GPC show that the molecular weight of titanium( IV) and molybdenum (VI) species are 9.80× 10² and 1.03 × 10³ respectively. The results of the thermal analysis agree with those based on amine extraction methods and the IR spectra. These observations lead us to a conclusion that the extracted titanium (IV) and molybdenum (VI) species from aqueous oxalic acid solutions predominantly consist of (R₃NH)₂, TiO (C₂O₄)₂·2H₂O and (R₃NH)₂MoO₂(C₂O₄)₂, respectively.

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The photochemical reduction of p-benzoquinone sensitized by chlorophylls (chlorophyll a and pheophytin a) has been studied in aqueous organic solvents. When EDTA was used as an electron donor, p-benzoquinone was reduced quantitatively to hydroquinone in aqueous dimethyl sulfoxide, N, N-dimethylacetamide, and N, N-dimethylformamide. Both acetonitrile and 2propanol were unfavorable solvents f or this photoreduction. When Na₂[Co(edta)] was used in place of EDTA, the irradiation gave hydroquinone in good yields even when aqueous acetonitrile and 2-propanol were used as the solvents. Plausible mechanisms for these photosensitized reductions have been discussed.

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Although it is well-known that an alkoxide cannot reduce carbon-carbon double bond, >C=C<, to >CH-CH> because of its weak reducing power, 9-alkylidenefluorenes e. g., 9-ethylidene[10], 9-isoporopylidene- [11], 9-benzylidene- [12], 1-methyl-9-ethylidene-[13], 1-methyl-9-benzylidene-[14], and 9-benzhydrylidene-fluorene [15] were reduced quantitatively to the corresponding 9-alkylfluorenes i. e., 9-ethyl- [17], 9-isopropyl-[18], 9-benzyl[19], 9-ethyl-l-methyl- [20], 9-benzy1-1-methyl- [21], and 9-benzhydrylfluorene [22] by heating with sodium isopropoxide-2-propanol in a sealed tube. Under refluxing with sodium isopropoxide in 2-propanol, 9-alkylidenefluorene of larger polarity with regard to C(9)=C bond was more easily reduced to 9-alkylfluorene.

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As a part of research on the removal of sulfur from petroleum and coal products with metallic sodium, the susceptibility to the decomposition of organic sulfur compounds having different structural features by metallic sodium and factors affecting the decomposition of thiophene have been investigated. Reactions were carried out in a glass ample containing the stoichiometric amount of sodium (assuming conversion of S to Na₂S) at 200°.
In hexane or xylene, diphenyl sulfide and benzo[ b ]thiophene were readily decomposed, while the decomposition rates of thiophene, dibenzothiophene and dibutyl sulfide were comparatively slow (Fig.1 and 2).2-Butanethiol was resistant to the decomposition. The decomposition of thiophene was markedly affected by solvents used, and was found to be very rapid in tetralin and very slow in benzene (Fig.3). The great acceleration effect of tetralin has been suggested to be attributed to the great hydrogen-donating capability, because the addition of tetralin and other aromatic hydrogen donors to a benzene solution accelerated the decomposition in accordance with relative hydrogen-donating capabilities of the additives (Table 1). On the other hand, naphthalene and phenanthrene, the reduction poduction potentials of which are lower than that of benzene, caused greater decrease in the thiophene decomposition efficiency than benzene (Table 2). This inhibitory action of aromatic hydrocarbons is probably due to the electron transfer process from sodium to the hydrocarbons which is competitive with the electron transfer to thiophene. The fact that thiophene was hardly decomposed in benzene may be interpreted in the same way. Hydrogen gas also retarded the thiophene decomposition (Table 4).

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The optical resolution of DL-α-phenylglycine (DL-Phg) sulfate was attempted in 30 wt%H₂SO₄ by preferential crystallization procedure. The resolutions were carried out under the conditions of several temperatures (-5, 0, 5, 10 and 20°C), the degrees of supersaturation of racemic solution (110 and 130%) and the resolution times (5, 10, 15 and 20 minute). The resolution of DL-Phg sulfate was possible at -5-5°C, but not at 10 and 20°C. The D-Phg sulfate resolved from the racemic solution with the degree of supersaturation of 110%, at 0and 5°C and the short resolution time (5 minute) had high optical purity which was higher than 95%, and the degree of resolution was higher than 61%. Then, it is presumed that DL-Phg sulfate is conglomerate in the temperature range of -5-5°C from the above results of the resolutions, and is racemic compound at the temperature higher than 10°C by comparing the IR spectra of DL- and D-Phg sulfate and the result of the melting point binary phase diagram.

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In order to elucidate the characteristics of phenol-formaldehyde type resins as chelating ion-exchange resins, resorinol-formaldehyde resin, α-resorcylic acid-formaldehyde resin (α-RA resin) and the other chelating ion-exchange resins of phenol-formaldehyde type were prepared, and their properties for metal ion adsorption were investigated by the equilibrium method and the column method. The apparent ionization constants (pK') were calculated from pH-titration curves of the resins and the values of ion-exchange capacity. The resins were examined on the ionization of their functional groups. In the equilibrium method, all the resins (except for α-RA resin) showed the following selectivity for metal ions:
Pb²⁺≈Cu²⁺>>Zn²⁺≈Ni²⁺>Ca²⁺>Mg²⁺>>K⁺>Na⁺
α-RA Resin showed as follows:
Pb²⁺≈Cu²⁺>>Ca²⁺≈Mg²⁺>>K⁺>Na⁺
In the column method, the selectivities of all the resins were similar to those in the equilibrium method. A column made of α-RA resin showed remarkable selectivity in the adsorption of CO²⁺ and/or Mg²⁺ from aqueous solution containing much of NaCl and a little of Ca²⁺ and/or Mg²⁺. The solution volume, that could be treated by use of α-RA resin column, was much smaller ( =1/7) than that obtained by use of UR-40 resin column. But, those resins can be prepared much more easily than UR-40 resin. Futher, it may be deduced, from pH-titration curves and pK', that the ionization states of functional groups in the resins altered after the monomers were polymerized.

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Styrene-butadiene popcorn (SBP) was allowed to react with maleic anhydride, mercaptoacetic acid, dithiodiacetic acid, acetic acid, and carbon tetrachloride in the presence of a radical initiator to introduce some amount of carboxyl groups probably useful as an ion-exchanger. In the presence of benzoyl peroxide (BPO) as a radical initiator, the maximum amounts of carboxyl groups introduced were O.49, O.30 and O.32 mmol/g for maleic anhydride, mercaptoacetic acid and dithiodiacetic acid, respectively, whereas α, α'-azobis(isobutyronitrile) was not effective as an initiator. The chlorine content was 11% in the reaction of SBP with carbon tetrachloride in the presence of BPO. No carboxyl group was introduced by acetic acid with di-t-butyl peroxide as an initiator. The reaction product with maleic anhydride showed an absorption at 960 cm^-1 due to carbon-carbon double bonds which were weaker than those of the starting SBP. In other reaction products, the absorbance at 960 cm^-1 remained unchanged relative to that of the starting SBP. Therefore, the reactions with the reagents other than maleic anhydride are concluded to take place preferentially at allylic or benzylic carbons rather than at the double bonds.

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Adsorbability of heavy metal ion on activated carbon is strikingly affected by the existence of co-adsorbate. Especially, the charge of metal complex formed with co-adsorbate will dominate the adsorbability of the metal ion. In this paper, adsorption capacity of activated carbon for charged adsorbate was tested by the use of trimethylphenylammonium chloride (cation), benzyl alcohol (nonion) and benzoic acid (nonion, anion), and then, adsorbability of heavy metal ions (Cu²⁺, Cd²⁺, Hg²⁺) was studied in the presence of organic ligands (edta, 1, 10-phenanthroline, glycine, salicylic acid, picolini acid, cysteine) which formed the different charged complexes with the metal ions. Nonionic organic compounds (Fig.1) and nonionic metal complexes (Fig.4, 5, 7) were most adsorbed on the activated carbon. In addition, the adsorbability of nonionic complexes was little affected by both pH (Fig.4, 5) and the presence of excess amount of co-adsorbates (Fig.7), while the adsorbability of anionic complexes was strikingly interfered by the presence of excess amount of co-adsorbate (Fig.7). From these results, it is concluded that the activated carbon used in this experiments effectively adsorbes the metal ion as nonionic complexes. However, the adsorption mechanism of Hg²⁺ ion was so complex that it could not be clarified in this study. The effect of pH on the adsorption of Hg²⁺-edta complex (Fig.6)differed from the cases of Cu" and Cd2+-edta complexes (Fig.4).

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The mechanism of thermal decomposition of cerium(III) acetate anhydride was studied in atmospheres of N2, He and, Ar by TG, DTA, X-ray diffraction, infrared spectroscopy, mass spectroscopy and chemical analysis. The anhydride shows another crystallographic transformation at 230°C, giving the anhydride of the stable form in high temperature its anhydrous cerium(III) acetate is a new polymorph of anhydride. The anhydrous cerium(III) acetate decomposes in the temperature range of 300-550°C to cerium(IV) oxide through three intermediate compounds. Presumably these new intermediate compounds have the compositions of Ce₈O₃ (CH₃COO)₁₈, CeOCH₃COO and Ce₂O₂CO₃.

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The direct synthesis of nitriles [1] J has been carried out by the reaction of nitroalkanes with triphenylphosphine/carbon tetrachloride in the presence of triethylamine. The yields of [1] were 60-98%, and the presence of ethyl acrylate in this system gave a mixture of [1]and 2-isooxazoline derivatives [3]. On the basis of these results, it is concluded that the reaction proceeds through nitrile oxide [2], which is formed as an intermediate by the elimination of water from nitroalkane with triphenylphosphin/icarbon tetrachloride and then gives [1] by the deoxidation with excess triphenylphosphine.

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Alkyl aryl ethers have obtained in a high yield from sodium phenolates with alcohols as an alkylating agent in the presence of triphenylphosphine and carbon tetrachloride under mild conditions. The yields of ethers were hardly affected by the polarity of the substituent on phenols, but it was decreased remarkably by the use of tertiary alcohols as an alkylating agent. The use of a mixture of phenol and piperazine instead of sodium phenolate gave mainly alkyl chlorides.

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Optical resolution by the preferential crystallization procedure has been applied to ammonium N-benzoyl-DL-alaninate (NH₄-DL-BzAla). It was found by comparing the melting point, solubility and infrared spectrum of NH₄-DL-BzAla with those of NH4-L-BzAla that NH₄-DLBzAla was conglomerate. The optical, resolution was carried out for a series of supersaturated solutions (141, 156 and 170%) of NH₄-DL-BzAla in ethanol at 10°C with the resolution times of 10, 20, 30, 40 and 50 min. The NH₄-L-BzAla sample obtained from the racemic solution with the degree of supersaturation of 141% and the resolution times of 30-50 min had the optical purity of 80-91% and the degree of resolution of 43-62%.

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The continuous foam fractionation of phenol using ethylhexadecyldimethylammonium bromide(EHDA-Br) has been investigated. Such effects as feed concentration of phenol, feed concentration of EHDA-Br, pH, and the presence of competing anions on the foam separation of phenol were examined. Data were analyzed in terms of the ratios of effluent flow rate to feed flow rate, the removal ratios, and the enrichment ratios. The influences of the feed concentrations were expressed by Eqs. (4)-(8). The highest removal of phenol was attained at about pH 12. The effect of divalent sulfate ion on the removal of phenol was more prominent than that of monovalent chloride ion.

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