Ohya-ishi powder contains many minerals and clay minerals. A mineralogical discussion concerning Ohya-ishi has been carried out. Taking a notice of mineralogical constituents, this experiment was made in order to study the adsorptive capacity of Ohya-ishi powder as liquid phase adsorbent for aqueous Methylene Blue solution.
Ohya-ishi samples used for this experiment were prepared by the classification with several screens and a Nöble elutriation apparatus after an original piece of Ohya-ishi was crushed. Some samples heat-terated were also used. Adsorptive capacity of these samples was measured with the liquid-solid contact method by a batch process, and the relation between these values and mineralogical constituents of the samples were examined with the method of X-ray powder diffraction and DTA. From the results of the experiment, it was found that Methylene Blue molecules were adsorbed in Ohya-ishi powder when 1.0 g of this powder was added into 100 ml aqueous solution with the concentration of 250 μg/m/, and it was also found that coloring matter was removed and the solution became colorless and transparent. Moreover, adsorptive capacities were strongly influenced by the particle diameter and the heat treatments. It was ascertained that Ohya-ishi powder has high adsorptive capacity for aqueous Methylene Blue solution, and samples having finer particle diameters are more effective for the removal of Methylene Blue.
Comparing the hardness indexes of the component minerals contained in Ohya-ishi powder, smectite group including montmorillonite and saponite as accessory ingredients has a low hardness index, and these minerals are easily crushed at the initial stage of grinding, and transferred and collected in the samples having small particle diameters. Furthermore, these minerals have a tendency to lose the adsorptive capacity by the heat treatments. So it can be concluded that these minerals can contribute to the removal of Methylene Blue molecules.

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The evolution of sulfur oxides from the SO₂-adsorbed Fe (III) hydroxide oxides (α-, β-, and γ-FeOOH) was examined by the temperature programmed desorption (TPD) method in the temperature range between 30 and 600°C. TPD spectra of α-FeOOH and γ-FeOOH showed peaks at 130, 230, and 500°C (Figs.2 and 4). As for β-FeOOH, in addition to 130 and 230°C peaks, other two peaks appeared at 300 and 430°C corresponding to the structural transformation from FeOOH to α-Fe₂O₃ (Fig.3). The chemical analysis of the desorbed gases indicated that a portion of adsorbed SO₂ molecules is desorbed as SO₃ at 230 and 500°C, and that the evolved gas at 130°C consists of SO₂. The state of adsorption of SO2 was discussed with reference to the surface structures of each FeOOH crystal: SO₂ bound with the surface OH- evolves at 130°C and SO₂ bound with the surface O^2- at 230 and 500°C.
The TPD experiments have been carried out for SO₂ adsorbed on the sample pre-treated at the transformation temperature from FeOOH to α-Fe₂O₃. The results indicated that the surface O^2- is highly active to SO₂ in an intermediate state between the original FeOOH and the resultant Fe₂O₃, because the SO₃ content is considerably high (Fig.9) and the activation energy of desorption of SO₂ is low (Fig.10) at the transformation temperature.

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The mechanism for the absorption of NOx (NO+NO₂) gas mixtures in ammonium sulfite solutions was investigated for preparing hydroxylamine by use of a packed-bed absorber. The NOx gas of 10 vol% was absorbed in ammonium sulfite solutions at NO₂/NOx molar ratios of 0.25 to 0.75 mol/mol, temperatures of 0 to 40°C, pHs of 5.4 to 9.3 and sulfite concentrations of 0.045 to 1.58 mo/ll. Main products were NO₂- and HON (SO₃)₂^2- and by-products were N₂, N (SO₃)₃^3-, NO₃- and N₂O.
Although any appreciable amount of HS0₃- was not present in pH 8.0 to 9.3 region, the reaction between NO₂- and HSO₃- took place to form a considerable amount of HON (SO₃)₂^2-The formation of HON (SO₃) ₂^2- was increased in pH below 8.0. Different from the absorption in other alkaline solutions such as an ammonium carbonate solution, any appreciable amount of NO₃- was not produced in all the experiments unless the sulfite concentration was low.

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The phase diagram of theCaMnO_3-x, system (Fig.1) has been constructed in the temperature range of 650 to 1300°C and in the oxygen partial pressure region of 1 to 3 × 10^-3 atm by means of gravimetric, quenching and X-ray diffraction techniques. The phases found are cubic, tetragonal, and orthorhombic perovskite-type structures. The oxygen deficit in tetragonal and orthorhombic phases increases with increasing temperature and with decreasing oxygen partial pressure. The densities of these phases, determined pycnometrically and by X-ray diffraction technique, decrease with an increase in oxygen deficit.

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Recently, the wet removement methods of nitrogen oxides by using the thiourea in aqueous solution containing small amounts of copper salts was reported as a patent. As the basic study on the removement method, the amounts of thiocyanic acid produced by the reaction of thiourea (tu) complexes of several transition metals with nitrous acid were determined. The results showed that the copper(I) complex is more stable than the other complexes. When the copper(I) complex underwent reaction with nitrous acid or nitrogen dioxide gas in we ak alkaline media, pale yellow crystals of copper(I) complex were obtained. When the complex underwent reaction with nitrous acid in acidic media containing excess thiourea, white crystals which are very insoluble in water and other solvents were obtained. Elemental analysis and measurements of infrared and electronic absorption spectra for these two complexes indicated that the pale yellow complex is a nitrito (thiourea)copper (I) complex Cu (tu) (ONO), and the white one is a sulfate salt of tris(thiourea)copper(I) complex, [Cu(tu)₃]₂SO₄.

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Dimercaptomaleonitrile (mnt, H₂L) reacts with nickel (II) and mercury (II) to form stable water-soluble complexes, respectively.
A stability constant of the mercury complex, β₂^HgL2, was determined by the measurments of the ligand exchange equilibria:
The value of log β₂^HgL2 was determined to be 43.31 at ionic strength, I=0.3 ( NaClO₄) and 25±0.1°C.

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The corrosion potential Ecorr of aluminum with a purity of 99.5% in hydrochloric acid solutions at high concentration levels was measured. Ecowas well correlatedwith the concentration of hydrochloric acid [HC1] up to about 1 mol⋅dm^-3 in the manner as where A ≅-790 mV vs. SCE and ≅-120 mV/decade. This relation was slightly affected by temperature, oxidation-reduction atomosphere, immersion time, and stirring of solution. The apparent electrical impedance of the measuring system was as low as 2Ω⋅cm² when [HC1] =1mol⋅dm^-3. The continuous renewal of the aluminum surface due to corrosion minimized t he hysteresis of the measurement.
These features were favorable to the sensor of hydrochlolic acid in the industrial field.

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The electron capture detector (ECD) has the highest sensitivity to the Cr (III) complexes of acetylacetone, trifluoroacetylacetone, and hexafluoroacetylacetone. The electron capturing processes of these complexes were investigated by determining electron capture coefficients (K) at various detection temperatures. Based on the slopes of Arrhenius plots of in K and in KT^3/2 for Cr (acac)₃, Cr(tfa)₃ and Cr(hfa)₃ the types of electron capturing reactions are discussed. Sin ce the slopes of the plots are negative for Cr(acac)₃ this compound is considered to capture free electrons dissociatively. As for Cr(tfa)₃ and Cr (hfa)the plots show potsitive slopes, indicating that these compounds capture free electrons nondissociatively. The activation energy for the dissociative electron capture reaction of Cr (acac), was calculated as 51.5 kJ/mol by using the equation, in K=Z-E* /RT. The electron affinities for the nondissociative elecron capture reactions of Cr(tfa)₃ and Cr(hfa)₃ were determined to be 55.6 kJ/mol and 39.7 kJ/mol, respectively, by using the equation, In KT^3/2=Z+1-EA/RT. The obtained value of the electron affinity for Cr(tfa)₃ is larger than that for Cr(hfa)₃. The heats of solution(ΔHs) were determined by gas chromatography in order to obtain information on thermodynamical behavior of these metal complexes in column. The values of ΔHs for Cr (acac)₃ fac- and mer-Cr(tfa)₃ and Cr (hfa)₃ were 64.0, 68.6, 68.6, and 42.3 kJ/mol, respectively.

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Cellulose triacetate tips were obtained by cutting off filaments, which were produced by means of dry spinning out of a dichloromethane-ethanol solution containing cellulose t riacetate. C ellulose triacetate beads were produced by melting the tips in heated silicone oil. Meanwhile, cellulose triacetate and cellulose diacetate beads were also produced by suspendin g a dichsololro-methane ution of cellulose triacetate and a dichloromethane -ethanol solution of cellulose diacetate in an aqueous solution of gelatine with stirring, respectively, and then by evaporating the solvents. Composite gel beads of cellulose triacetate and starch tria cetate were produced similarly. Cellulose beads and porous cellulose beads were produced by sapo nification of the beads d escribed above. The cellulose beads ranging from 5 to 500 μm i n diameter were obtained especially by the suspending method. The cellulose gels were found to be available as packing materials for gel chromatography.

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Various types of bead-shaped cellulosic ion exchangers were prepared from bead-shaped cellulose or crosslinked bead-shaped cellulose or crosslinked porous bead-shaped cellulose. Diethylaminoethyl (DEAE) -cellulose and ECTEOLA-cellulose were prepared by the reaction of the basic materials with 2-chlorotriethylamine hydrochloride and a mixture of epichlorohydrin and triethanolamine, respectively. Their anion-exchange capacities and degrees of swelling were ∼2.7 ∼0.5 meq/g and∼29 ∼6.2 ml/g, respectively. Carboxymethyl (CM) -ce llulose, sulfomethyl (SM) -cellulose and phospho (P) -cellulose were prepared by the reaction o f the basic materials with chloroacetic acid, sodium chloromethanesulfonate and phosphoryl chloride, respectively. Their cation-exchange capacities and degrees of swelling were ∼2.2, ∼0.9, 1.8 m eq/g and ∼47, ∼49, ∼10 ml/g, respectively. Excluded critical mo lecular weights (Mum)of the ion exchangers from crosslinked porous cellulose beads were larger than those from crosslinked cellulose beads. For example, Mum of diethylaminoethyl-cellulose from the former was 4 times larger than that from the latter.

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The reaction of 1, 4-naphthoquinone-2-sulfonate (NQS) with Na₂SO₃ has been examined and compared with that of p-benzoquinonesulfonate (PQS). The former reaction takes place when the redox potential of NQS (ENQS) is more negative than that of Na₂SO₃ (Ess). On the other hand, the latter reaction proceeds under the conditions that the redox potential of PQS (Ems)is more positive than Ess.
The reaction of NQ S with Na₂SO₃ did not practically proceed at pH<2.6, but gave a quantitative yield of 1, 4-dioxo-1, 2, 3, 4-tetrahydro-2, 3-naphthalenedisulfonate at pH>7. In contrast, the reaction of PQS with Na₂S0₃ gave hydroquinonesulfonate in the strongly acidic media, 3-hydroxy-6-oxo-2, 4-cyclohexadiene-1, 2-disulfonate in the weakly acidic media, and hydroquinonedisulfonate via 1, 4-addition in the alkaline media.

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Optical activation of 2-phenylpropionaldehyde (PPA) and 3-(p-cumy1)-2-methylpropionaldehyde (CPA) via enamines has been studied, employing (S)-2-isopropyl-1-methylpiperazine J and (S)-3-isopropyl-1-methylpiperazine [2] as the se c[o1n] dary amine components of the enamines. Whe, n [2] J was used as the amine component, the optical rotation of CPA recovered by hydrolysis of the enamine was significantly dependent on the acids. However, the optical rotation of CPA from the enamine of [1] J was found to be moderately positive and almost constant. The ¹H-NMR spectrum of the iminium salt of CPA enamine of [1]showed the signals of the isopropyl substituent of the piperazine shifted slightly to the higher field (Table 3). The occurrence of the CH-π interaction between the isopropyl substituent o f the piperazine and the phenyl group in the aldehyde moiety was suggested (Scheme 4).
From the deuterium labeling experiments of the enamines, the optical activation of CPA via the enamine with [2] was considered to be kinetically controlled, while that of the enamine with Li J to be thermodynamically controlled. This would coincide with the presence of the iminium salt stabilized by the CH-n-interaction. An explanation on the dredominant formation of S(+)-CPA was given, based on the expected preference of one of the possible iminium salts, (S)-salt, over another, (R)-salt, from stereochemical points of view (Scheme 4).

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The Friedel-Crafts benzylation of benzene derivatives with substituted benzyl alcohols was carried out in the presence of titanium (IV) chloride to compare its catalytic effect with that of aluminium chloride. The ortho-para ratio in the products of the Fries rearrangement of a few m-substituted phenyl benzoates was also compared between the two catalysts. When three kinds of benzyl alcohols were treated with TiCl₃ in ether, the corresponding benzyl chlorides were obtained and the substituent effect on the yield was found. Whereas the equimolar reaction of azoxybenzene with TiCl₄ gave azobenzene, 4-chloroazobenzene was obtained in high yield in the reaction with excess TiCl₄. A similar results was obtained in the reaction of azoxybenzene with AlCl₃.

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2, 3-Dicyano-1, 4-naphthoquinone [1], which is expected to be a strong electron acceptor, is an interesting compound. For the synthesis of coloring matters, 5-amino-2, 3-dicyano-1, 4naphthoquinone [5] was prepared from 2, 3-dichloro-5-nitro-1, 4-naphthoquinone [3] by cyanation, reduction and oxidation. The reactions of [5] with anilines (aniline [9], p-toluidine [10], p-anisidine [11], p-chloroaniline [12], N, N-dimethyl-p-phenylenediamine [13]) were carried out. Anilines [9]∼[13] gave [9a]∼[13a] (8-substitution) as major products, in which the 8-position of [5] reacted with amino group of anilines, and [9b]∼[12b](CN-substitution)as minor products, in which the cyano group is substituted by amino group.
The structure of [9b] was determined as the 2-substituted by the synthesis from a known compound. The 8-position substitution in [5] is rather unusual and interesting, therefore more detailed investigation of the reaction was carried out under various conditions.
The mechanism for the formation of [9a] and [9b] were discussed from the se results.5-Nitro-[4], 6-nitro-[7] and 6-amino-2, 3-dicyano-1, 4-naphthoquinones [8] were synth esized and the CN-substituted products were obtained by the reaction with aniline, but 8-substitution could not be observed. According to the visible absorption measurements of the obtained compounds, the bathochromic shift were shown more 300 nm by the 8-substituted [9a]∼[12a] than the CN-substituted [9b]∼[12b].

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Reductions with sodium monosulfide and catalytic reduction (catalyst; palladium-carbon)of 4, 6-disubstituted 2- (p-nitrophenylazo) -1, 3, 5-triazines [2a∼j] (substituents; a:N(CH₃)₂, N(CH₃)₂, b:N(C₂H₅)₂, N(C₂H₅)₂, c:N(CH₃)₂, N(C₂H₄CN)₂, d:NC₄H₆, NC₄H₆, e:NC₄H₆O, NC₄H₆O, f:NH₂, NH₂, g:NHC₆H₅, NHC₆H₅, h:N(CH₃)₂, C₆H₅, i:OCH₃, OCH₃, j:OC₆H₅, OC₆H₅) were studied.
By reduction of [2a∼e] with sodium monosulfide, in which nitro group of these cornpounds were reduced to amino group in preference to azo group, the corresponding 2- (paminophenylazo)-1, 3, 5-triazines [3a∼e] were obtained; and of [2f∼j]the corresponding 2(p-nitrophenylhydrazino) -1, 3, 5-triazines [1f∼j] were obtained as the results of reduction of azo group to hydrazo group. On the other hand, catalytic reduction which occurred selectivel y at nitro group of all [2], except for [2c], gave [3a], [3b] and [3a∼j] Furtheremore, methyl derivatives [4a∼e] of [3a∼e] and ethyl derivative [4a'] of [3a] were synthesized by dialkylation of amino group. Absorption maxima of [3a∼j] [4a∼e] and [4a']in ethanol were observed to be 403∼476 nm in visible region.

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The conducting mechanism of amino compounds was studied by the use of N-hydroxyethyl and N-2-methoxyethyl derivatives obtained from aniline and N-methylaniline. An electrical conduction occurs by charge transfer from N to H when molecules approach. The efficiency of electrical conduction is considered to be related with the electron density of N and with the hydrogen-bond strength between N and H. When the amino compound absorbs moisture, it shows an ionic conduction, and is therefore considered to have an ionic structure.

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Reverse osmosis separation of many kinds of polar organic solutes (alcohols, phenols, aldehydes, ketones, organic acids or bases) by a cationic charged composite membrane was examined. The correlation between solute rejection and polar parameters for these organic solutes have been investigated. The solute permeation was carried out in single-solute aqueous solution (100∼1000 ppm) under applied pressure of 80 kg/cm² at 25°C.
Solute rejection for alcohols, aldehydes and ketones are at c l ose relationship with Taft's numbers and acidities of these solutes which represent the effect of the substituent group on the polar effect of the molecule. Solute rejection decreases with increasing Taft's number (σ* or Σσ* ) and acidity of the solute (Δvs). For alkanols, solute rejection increases with increasing molecular weight and/or degree of molecular branching. For organic acids or bases, such as phenols, aniline derivatives, acetic acid and methylamine, solute rejection are dependent upon dissociation constant (pKa) and the degree of dissociation (α) of the solute. Solute rejection increases proportionally with dissociation constant and the degree of dissociation of the solutes.
These results suggest that organic solute rejections of a cationic charged composite reverse osmosis membrane are governed mainly by the following three factors; electrostatic repulsion between fixed charged groups and ionic solutes, the acidity for undissociated solute, and the chemical affinity between solute and membrane material.

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Kinetics of thermal decomposition of manganese(IV) oxide ore particles into manganese(III)oxide under the condition of reduced pressure was studied by using a vacuum thermobalance. The pressure in the reaction tube was kept at ca.10^-3mmHg and a weigh t loss was isothermally measured. The over-all rate equation derived by using two controlling mechanisms was applied to the thermal decomposition of manganese(IV) oxide ore particles, and the rate constant kc and the interparticle effective diffusivity De were determined. By comparing the resistance of the interfacial reaction with that of the mass transfer, it was concluded that the over-all reaction rate is mainly determined by the interfacial reaction at early stage, but it is determined by the resistances of both the interfacial reaction and the mass transfer because the resistance of the mass transfer gradually increased with decomposition time.

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In order to develop a deodorization process of (CH₃)₂S, the performance of various ion-exchanged Y-type zeolites (NaY) for the adsorptive removal of (CH₃)₂S at low concentration level was investigated. H(I), Ag (I), Co (11, Ni (II), Cu (II) and Zn (II) were studied as exchanged ions. The experiments were carried out by using a packed bed flow apparatus under the a tm ospheric pressure at 40∼200°C. For the adsorption, the inlet gas a mixture of 100 ppm (CH₃)₂S, H₂O (0∼8%) and N₂, and the total flow rate was 500 N crnsimin for 0.5 and 1.0 m l of the adsorbent with average diameter of 0, 25 and 0, 5 mm. Fr the desorption, the conditions were the same as that for the adsorption except for the absence of (CH₃)₂S. The holding capacity of (CH₃)₂S was determined by deducting the desorption amount from the adsorption amount. The adsorptive removal capacity of (CH₃)₂S at a very low concentration level (<0.2 ppm) was evaluated by the holding capacity. Also, the temperature-programed desorption curve (2.5°C/min flowing air) was measured to examine the stability of (CH₃)₂S held on the adsorbent. A nd the following results were obtained:
1) Ag(I)-NaY is a good adsorb ent for (CH₃)₂S at alow concentration level. Also, Cu (II)-NaY is a good adsorbent in the absence of water vapor.
2) Ag(I)-NaY and Cu (II)-NaY can be regenerated by the following treatments: (CH₃)₂S adsorbed in the absence of water vapor is treated, with flowing steam, and (CH₃)₂S adsorbed on Ag(I)-NaY in the presence of water vapor is treated with flowing air from the adsorption temperature to 500°C (2.5°C/min).
3) The exchanged me tal ion contributes to the adsorption. (CH₃)₂S held on Ag(I)-NaY is stable for heating, and the desorption occurs above ca.160°C. (CH₃)₂S seems to form a coordination compound with Ag (I) ion.

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Cr (VI) was effectively removed from aqueous potassium dichromate solution by using hydrazine hydrate and activated carbon simultaneously. In the presence of activated carbon, Cr (VI)was rapidly reduced to Cr (III) with hydrazine hydrate and readily precipitated as chromium (III)hydroxide in the pH range from 5.5 to 7.0 (Fig.3).
The activated carbon promoted the reduction rate and adsorbed or coag ulated the resulting precipitate. The rate of this reaction was first order with respect to the concentration of Cr (VI) and the relationship between the rate constant k (min^-1) and the additional amount of activated carbon M (mg/l) was expressed as follows (Fig.7).

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The solution of poly (vinyl chloride) (PVC) in N, N-dimethylformamide (DMF) was heated at 100∼200°C for 5 h in the presence of ammonia in an autoclave. The reaction gave two sorts of chemically modified polymers, soluble and insoluble in DMF, accompanied with ammonium chloride. No hydrogen chloride evolution was ovserved throughout the reaction.
Structural analyses of the resulting soluble polymer indicated that there was no amino group but dimethylamino group which replaced the chlorine atom of PVC as much as 30% of the monomeric unit besides the double bond unit (70%). The dimethylamination might be resulted from the amino group exchange reaction between DMF and ammonia. The DMF soluble polymer showed high adsorvitivities (0.2 mmol/g-resin) toward Cu²⁺ or Ni²⁺ in aqueous solution.

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Positronium reaction rate constants kp of pyridinium, quinolinium and 1, 10phenanthrolinium ions were determined in acid aqueous and acid methanolic solutions. Although rather large kp values were obtained for quinolinium and phenanthrolinium ions in water, the positronium quenching by these ions as well as by pyridinium ion was practically absent in methanolic solutions (see Table 1). This result is in qualitative agreement with the prediction based on the “internal pressure effect model” for the solvent effect in the positronium complex formation reaction.

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Polynitration of fluorene was examined.2, 4, 7-Trinitrofluorene (TNF), mp 207∼208°C, and 2, 4, 5, 7-tetranitrofluorene (TENF), mp 272∼273°C (dec. ), were obtained in yields of 40 and 50%, respectively, by nitration of fluorene with a mixture of nitric acid (d¹⁵₄=1.52) and sulfuric acid (95%) in acetic acid. UV spectra of the solutions of TNF and TENF in ethanol changed with the lapse of time. TNF and TENF formed molecular complexes with some polycyclic aromatic compounds.

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Palladium (II)-copper (II)-catalyzed synthesis of alkylpyridines from ethylene and alkylamines was studied. The reaction of methylamine with ethylene produced in good yields a mixture containing pyridine and 3-methylpyridine. Ethylamine gave 2-methylpyridine and 5-ethyl-2methylpyridine, whereas ethylenediamine did not react with ethylene under similar reaction conditions. Paraldehyde was found to be used in place of ethylene in these reactions to give the same products.

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Synthsis of pyridine and 3-methylpyridine was successfully carried out by the reaction of C, compounds with ammonia and ethylene in the presence of Pd(II)-Cu (II) as catalyst. It was confirmed that 1, 3, 5-trioxane, paraformaldehyde, formalin, dichloromethane, methylal and methylamine, which would give formaldehyde under the reaction conditions, served as the C, compounds in the present synthesis.

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