The solution behavior of poly (oxyethylene) hydrogenated castor oils (EC) and poly (oxyethylene)sorbitol tetroleates (ESTO) with different oxyethylene chain length in water was investigated and discussed in comparison with that of poly (oxyethylene) nonylphenyl ether (NP). Their binary phase diagrams were obtained by a polarizing microscopic technique and differential scanninig calorimetry.
With an inc rease of the oxyethylene chain length, the dissolved states of these surfactants in water changed from dispersion of concentric lamella liquid crystal to micellar solution at low concentrations. At relatively high concentrations however, it changed from neat phase to middle phase liquid crystal and further to micellar solution. These observations can be attributable to the decrease of the aggregation number of the aggregates. The aggregation number increased with a multiplication of the hydrophobic chain. When the dissolved states of NP, EC and ESTO each having the same clouding point were compared in the same constitution, EC formed the middle phase and ESTO formed the neat phase at low concentrations where NP formed the micellar solution. Furthermore EC and ESTO formed the neat phase at high concentrations where NP formed the middle phase liquid crystal. This study indicated that a surfactant with multi-hydrophobic chains acts more hydrophobically than an ordinary singlechain surfactant having the same H/L balance.

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The thermal dissociation kinetics of diarsenic pentaoxide (As₂O₅), nickel(II) arsenate (3NiO. As₂O₅), cobalt(fl) arsenate (3 CoO⋅As₂O₅), aluminium arsenate (AlAsO₄) and iron(III) arse nate (FeAsO₄) have been studied by T. G. technique. The activation energy ΔE (kcal/mol) of the dissociation reactions of each compound was dependent on the oxygen partial pressure Po₂. For all the compounds mentioned above, following relations between ΔE and ΔH were found:
where ΔH is the heat of the dissociation reaction in kcal of each compound producing 0.5mol As₄O₆ and 1 mol of O₂ gas. The dissociation rate of As₄O₆ gas species from the solid surface v was obtained as follows:
where K(=P_AS4O6^1/2⋅Po₂) is the equilibrium constant for the dissociation reaction of each compound.
Considering the above rate equations based on the rate equation of the free evaporation, mean molecular gas species AsO_1.5 (Po₂<0.2) and As₂O₃ (Po₂>0.5) are assumed to evaporate from all the arsenate compounds, though As₄O₆ molecule is the most stable in the measured temperature range.

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Reduction and reoxidation properties of trisilver dodecamolybdophosphate (Ag₃PMo₁₂O₄₀) in solid phase were examined. The rate of reduction was the first order with respect to hydro gen pressure and it had a high dependence on the average degree of oxdidation in the solid. Kinetic isotope effects on the rate of reduction with H₂ or D₂ was not found. A pulse reoxidation method indicated that the oxygen comsumption rate depended on the pulse interval: the longer the intermission, greater the reoxidation rate.
These results are interpreted on the basis of co ncentration gradient of oxide ion in the solid lattice. The high dependence of reduction rate on the average degree of oxidation in the solid is due to the difference between bulk and surface oxide ion concentration. The diffusion coefficients were evaluated by fitting the experimental curve to the theoretical one derived from a basic diffusional equation. The diffusion coefficients of oxide ion in the solid, obtained from both reduction and reoxidation experiments, agree ith one another in the order of magnitude, 10^-12∼10^-13cm²/s. The value is extraordinary high, when compared with that for usu al oxides.

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Ternary manganese oxides of La_1-xSrxMnO₃, La_1-xKxMnO₃ and La_1-xPbxMnO₃ with perovskite structure were prepared, and their physicochemical properties and electrocatalysis for oxygen reduction were studied. The crystal structures of La_1-xPbxMnO₃ and the other oxides were cubic and trigonal, respectively, and the lattice constants decreased with the increase of x. This decrease is attributable to the increase of Mn⁴⁺ in the lattice, whose radius is smaller than that of Mn³⁺. The resistivities, measured by a four prove method, also decrease with the increase of x, since the formation of the σ* conduction band is brought about by the increase of Mn⁴⁺. The oxygen reduction currents were measured in two testing systems, i. e., the dispersion system and the system using the Teflon bonded electrodes. The current-potential curves of the oxygen reduction measured in the dispersion system were dependent on the kind of the working electrodes (Pt and Au). Morever, the variation of the catalytic activity with x, obtained in the Lai, La_1-xSrxMnO₃ system, was different from that with the Teflon bonded electrode. These differences indicate that the dispersion system is not appropriate for the testing of the electrocatalytic activity for the oxygen reduction, but suggest that this system is useful for the evalution of the promoter of the electrocatalyst. It is found that the order of the electrocatalytic activity was Lai, La_1-xSrxMnO₃>La_1-xKxMnO₃>La_1-xPbxMnO₃, and that these activities increase with the increase of x, in the measurement using the Teflon bonded electrodes. These variations in the activity are explained by the theory of the σ* band formation previously reported.

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In the determination of beryllium with a graphite furnace atomizer, the suppression effects of coexisting chlorides on beryllium atomic absorption were examined under various analytical conditions. Two mechanisms for the chloride interference are proposed on the basis of the interaction between beryllium and the chlorides in the solutions and in the processes of drying and ashing. The first interference occurs with the chloride salts remaining at the atomization step. This interference can be eliminated by vaporizing the chlorides or converting them to other types of compounds such as oxides before the atomization step. The second arises from The coordination of the chlorides to beryllium, which can be prevented by addition of the masking reagents. Ammonium salt of EDTA is suitable as an additive for such a purpose because it is able to coordinate to both beryllium and coexisting cations. The addition of EDTA was successfully applied to the determination of beryllium in alloys based on copper or aluminium.

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A mixture of anion exchange, cation exchange and chelating resin beads shows an excellent ability to collect trace elements in water samples. Moreover, when the constituent resin beads have different adsorption characteristics and can be separated from water after concentrating reactions, the measurement of each kind of resin beads can allow chemical state analysis.
Commercially available resin beads (AG 1 X 8 Cl, AG 50 WX 8 Na and Chelex-100Na) were dried and sieved to give narrow bead size distribution. The mixture of anion exchange (200∼250 mesh, ROH, 0.2 g), cation exchange (115∼150 mesh, RH, 0.2 g) and chelating (<350 mesh CHLNa₂, 0.18 g) resin beads was added to the water sample. The resin beads were separ ated by filtration and dried under vacuum. Then, they were sieved by a 170 mesh and a 300 mesh standard sieve. Cr⁶⁺ was adsorbed by the anion-exchange resin beads. Cr³⁺ was concentrated onto the chelating and the cation exchange resin beads.It was distributed between the cation exchanger and the chelateformer when the concentration of total ions was low. With an increase in the amount of total ions, Cr³⁺ tended to be collected by the chelating resin. The separated and dried resin beads were fixed onto an adhesive tape to form a monolayer resin bead sample of excellent reproducibility. The proposed method (Fig.8) showed concentrating factors of 1000 and 500 for Cr⁶⁺and Cr³⁺ respectively. The lower detection limits were 2.3and 8∼10 ppb for Cr⁶⁺ and Cr³⁺ respectively, by a standard wavelength dispersive X-ray fluorescence spectrometer.

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An amperometric titration was developed for the micro determination of L-cysteine and Lcystine. The reduction current of iodate ion was measured at +0.6 V vs. SCE with a rotating (2000 rpm) platinum electrode. L-Cysteine and L-cystine could be titrated with O.05 ml portions of a potassium iodate solution at an interval of 5 s in the presence of 4 mol/l hydrochloric acid. The titration was carried out at about 45°C for L-cysteine and at room temperature for L-cystine. L-Cysteine (0.01∼1.8 mg) and L-cystine (0.5 mg) were determined with a relative error of less than 2.4%. The best results with a relative error and a coefficient of variation of less than 0.3% were obtainedin the amount range 0.2∼1.8 mg (2×10^-5 ∼ 2×10^-4mol/l) for L-cysteine and 0.1∼2.5 mg (5×10^-5∼2×10^-4mol/l) for L-cystine. The titration of a dilute L-cysteine solution ( ≤0.1 mg) was performed under nitrogen atmosphere. The whole procedure required only 5 min. The recommended procedure is as follows. Ten milliliters of the sample solution containing ca.1 mg of L-cysteine or L-cystine are introduced into the titration cell. Twenty milliliters of 10 moll/ hydrochloric acid and 20ml of water are added. The resulting solution is immediately titrated with 5×10^-3mol/l potassium iodate standard solution amperometrically.

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Thermal decomposition of several arenediazonium tetrafluoroborates in nitromethane gave the corresponding phenols as the main products, accompanying the corresponding fluorinated benzenes and benzoxazoles. The oxygen atom of the hydroxyl group of the products was proved to arise from nitromethane. Product analyses, kinetic results of the decomposition reaction, and the analyses of isomer distribution of products in the reaction of aromatic substrate with the diazonium salt suggested that the decomposition proceeded heterolytically, via aryl cation intermediates. In the decomposition of the p-methoxy derivative, however, a competition between heterolytic and homolytic pathways was suggested.

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Chemical properties were investigated for ammonium pyridinium imidobis (sulfate) [1]which was prepared by heating amidosulfuric acid in pyridine at 100°C for 10 min. Unexpectedly [1] was stable and hydrolyzed very slowly at room temperature. Refluxing [1]in pyridine at 115°C for 120 minutes yielded pyridinesulfur trioxide complex and ammonium amidosulfate. In pyridine, amidosulfuric acid and [1] were interconverted:
Prolonged heating of ammonium amidosulfate in pyridine gave diammonium imidobis (sulfate).From these rerults, it was concluded that aquo-ammono-sulfuric acids, including amidosulfuric acid, imidobis (sulfuric) acid, and their ammonium salts, in pyridine were first transformed into the complex salts of the general composition, (NH₃)m (SO₃)n which then rearranged into aquo-ammono-sulfates.

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Reactions of benzyl mono-, di-, and trichloroacetates with fluoride ion generated from potassium fluoride and 18-crown-6 were carried out at 100°C in sulfolane.
Benzyl chloroacetate gave benzyl fluoroacetate, the halo gen exchange ' product, in a high yield (93%). The reaction of benzyl trichloroacetate proceeded by fluoride ion attack to the carbonyl carbon to afford chloroform and benzyl fluoride [3] in addition to a small amount of benzyl chloride [4] J, and none of halogen-exchange products (CCl_3-nF_nCOOCH₂C₆H₅n=1∼3) were obtained. In the reaction of benzyl dichloroacetate, both the halogen exchange and the attack of fluoride anion to carbonyl carbon were observed, and the reaction products were dichloromethane, [3], [4], benzyl difluoroacetate, benzyl 3, 3, 3-trifluoropropionate, and benzyl 3, 3-dichloroacrylate. The reaction mechanisms were discussed.

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The reactions of alkyl diphenyl phosphites and diphenyl N, N-dialkylphosphoramidites with pyridine N-oxide were studied. The reaction followed the second order rate equation. The electron-attracting substituents on the phosphorus atom of alkyl diphenyl phosphites and diphenyl N, N-dialkylphosphoramidites accelerated the reactions. These observations indicate that the electrophilic attack of the phosphorus atom on the oxygen atom of pyridine N-oxide is included in the rate determining step. The substituent effect can be explained in terms of the Taft's equation which contains both polar and steric substituent parameters. The reactivity of triphenyl derivatives of phosphorus, arsenic and antimony with pyridine N-oxide was found to be in the order: Ph₃P>>Ph₃Sb_??_ Ph₃As. Tris(p-chlorophenyl)phosphine reacted slightly faster with pyridine N-oxide than triphenylphosphine did. These results can be explained by the combined effect of electron acceptability of the group V elements and the stability of group V element-oxygen double bonds.

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2-(Trichlorovinyl) adipic acid has been prepared by the dehydration of 2- (trichlorovinyl) cyclohexanol [1b]b p with phosphoric acid, followed by the oxidation with potassium permanganate. Organic peroxide-induced substitution reaction of cyclohexanol with tetrachloroethylene gave 1- and 2-(trichlorovinyl)cyclohexanols ([1a] and [1b] ). The yields of [1a] and [1 b] were approximately equal, when di-t-butyl peroxide was used as an initiator. Dehydration of these compounds [1a]and 11 bp with phosphoric acid, gave 1- and 3-(trichlorovinyl) cyclohexenes ([2a] and [2b]) in 58% and 61% yields, respectively. Oxidation of [2 b] gave in 10%yield 2- (trichlorovinyl) adipic acid [4]. Adipic acid was obtained by the oxidation of [2a].

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Prim4. ry products and reactions on the ethene pyrolysis in the range of 750 to 890°C under atmosAeric pressure in the presence of high temperature diluents (steam and nitrogen ) has been stUdied. The pyrolysis was carried out by a flow method in a spherical quartz reactor.The range of the residence time was 0.02∼0.65s, and the range of the partial pressure of ethene was 0.02∼0.8 atm.
The reaction product s obtained in the pyrolysis were hydrogen, 1, 3-butadiene, acetylene, propene, methane, ethane, butenes, polymer and/or tar, and carbon. Initial produc t formed was an equimolar mixture of hydrogen and 1, 3-butadiene. A major product at the lower partial pressure of: ethene was acetylene. The acetylene formation was not concerned with 1, 3-butadiene formation, and that recognized as ax effect of the reactor wall. Steam dilution was different in the rate of over-all reaction from nitrogen dilution. The rate in the steam dilution was first-order with respect to ethene, though changed to zero-order at the partial pressure lower than 0.1atm, While that in the nitrogen dilution was approaching to secondorder.

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Coal liquids derived from hydrogenation of Taiheiyo coal were separated into aromatic fractions according to the size of the molecular weight by a sequence of separation procedures of solvent extraction, liquid chromatography and gel permeation chromatography.
The molecular weight of the GPC fractions measured by VPO gave good separation results indicating a gradual decrease from 390 to 210 with the increase of the fraction number (Fig.3). The mass spectral profiles measured by the low voltage-low resolution method for the respective GPC fractions shifted from the high molecular weight range for first eluted fractions to the low one for later eluted fractions. The spectral range were however considerably broad (Fig.4). Average molecular weight of each GPC fraction calculated by the mass spectra coincided fairly well with the results from VPO (Fig.5).
Compound types of aromatics in the GPC fractio ns were analysed by estimation of hydrogen deficiency (Z value) from the respective mass peaks. Distribution of molecular weight with different carbon number of alkyl substitution for each compound type was also estimated. These distributions shifted gradually from the low molecular weight range for the compound type having higher Z values to the higher range for lower' Z values, and were considerably narrow for each compound type, except for the fraction A-2 which was one of the first eluted fractions (Fig.6).
The average molecular weight of the respective compound type for each fraction showed good correlation with th6 elution volume (Fig.7). From these correlation, not only the average molecular weight but also information concerning the chemical structure of the GPC fractions were derived.
Distributions of each compound type were estimated from the intensities of individual mass peaks for all the fractions taking into account the correction of molecular ion sensitivities derived by Lumpkin (Fig.9).

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The removal of heavy metal ions by the method of ion flotation using a series of synthesized amidoxime-type surfactants was investigated.
The cyanoethylated compounds (R-AN) were obtained by treating 1-dodecanol or 1-dodecanethiol with acrylonitrile, and acrylonitrile telomers (Ls nAN) were obtained by the solution polymerization of acrylonitrile using 1-dodecanethiol and 2, 2'-azobisisobutyronitrile as a solvent and an initiator, respectively. These compounds were treated with hydroxylamine to obtain the corresponding amidoxime-type surfactants (R-AOx and Ls nAOx) (Table 1∼4).
Hg(II), Fe (III), Cu (II), Pb (II), Zn (II) and Cd (II) were effectively remov ed by using RAOx in appropriated pH ranges. The minimum values after treatment at pH 3 were: Hg 1ppm, Fe 2 ppm, and Cu 4 ppm (Figs.1 and 2). The content of ⁶⁰Co (II) was reduced to O.5ppb from 5.8 ppb at pH 5. The scums formed with the collectors were colored (Hg: yellow, Fe: purple, Cu: green, Co: pink). Hg (II) was selectively floated at pH 3 from a solution containing other metal ions. This could be ascribed to the stabilities of complexes and the HLB values. By using nonionic surfactants together with Ls 9.8 AOx, the removal efficiency increased greatly in comparison with the case of using L, 9.8 AOx alone (Figs.3 and 4).
These collectors can be effectively removed at neutral pH; the residual concentration o f R12AOx is below 78 ppb.

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The higher homologues of the title compounds [3] J (group 1 bearing 1-methyl and longchain acyl, group 2 long-chain 1-alkyl and acetyl, group 3 middle chain in both 1-alkyl and acyl) were readily prepared by acylation of 1-alkylpyridinio 2-imines [2] J derived from 2aminopyridine via 1-alkyl-2-aminopyridinium halogenides [1]. For the compounds belong to groups 2 and 3, the synthetic route appeared to be more favorable in both overall yield and operational convenience than the previous one involving the process of 1-alkylation of 2(acylamino) pyridine [4].
Catalytic action in the substitution reation of octyl bromide with aqueous potassium iodide was examined for [3] and [4]. All of [3] markedly accelerated the reaction, while no effect was observed for [4]. The catalytic efficency of [3] J increased in the order: group 1< group 3 < group 2. Some of groups 2 and 3 exhibited high ability comparable to that of “dicyclohexyl-18-crown-6”. The efficiency of groups 2 and 3 compounds apparently depende d on the alkyl chain length, having optimum carbon number (ranging 12∼16) of the hydrophobic parts. On the other hand, such a trend was not observed for group 1 compounds (see Fig.2). The results were explained by the structural effect on both the interaction of [3] w ith potassium salt and the hydrophilic-lipophilic balance of [3] for the phase transfer reaction.

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In order to study the solution behavior of polyphosphate compounds, light scattering and viscosity measurements were made on the aqueous solutions, with added sodium chloride, of potassium polyphosphate prepared under the various polymerization conditions. Under the control of heating time, potassium polyphosphate samples with a -wide variety of molecular weight were synthesized. The relationship between the weight-average molecular weight, Mw, and intrinsic viscosity, [η], of potassium polyphosphate in a saline solution (0.1mol/l) was represented by equation [η] = 1.80×10^-5 M^0.87at 25°C for the molecular weight ranging from 72000 to 1340000. On the other hand, the relationship between the z-average radius of gyration, (RG)z, and the weight-average molecular weight, Mw, could not be represented by one equation, showing different slopes in the low and high molecular weight regions. In view of the discrepancy between the viscosity and the gyration radius behavior, the polydispersity in molecular weight was examined on the several potassium polyphosphate samples by gel filtration and light scattering methods. The molecular weight distribution was found to be narrow for high molecular weight samples, but considerably broad for low molecular weight samples. After making correction of the effect of molecular weight distribution, two equations, [η]= =3.04×10^-5 M^0.83 and, [RG]w=0.48 M^0.52, were obtained for the molecular weight range from 93000 to 1340000.

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The kinetics of thermal decomposition of manganese (II) sulfate into trimanganese tetraoxide, and of manganese(IV) oxide into manganese(III) oxide under reduced pressure were studied by using a vacuum thermobalance on the basis of phase diagrams of the Mn-S-0 and Mn-O-T systems. The pressure in the reaction tube was kept at ca.10^-3mmHg and the weight loss was isothermally measured. For the analysis of the reaction rate, the heat transfer controlling model, the mass transfer controlling model, and the chemical reaction controlling model were examined, respectively.
(1) Thermal decomp osition of manganese (II) sulfate: The heat transfer controlling model and the mass transfer controlling model were not adopted. The chemical reaction on the interface was found to control the over-all reaction rate and the rate constant k was determined.
(2) Thermal decomposition of manganese(N) oxide: The heat transfer controlling model and the chemical reaction controlling model were not adopted. The mass transfer controlling model was found to express the over-all reaction rate and the effective diffusivity of oxygen gas within the solid particle was estimated.

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In order to establish a combustion method for a low NOx-emission, the relations among the gas composition, fractional oxidation of NH₃, CO, H₂ and fractional formation of NO, and the reaction mechanism in the NH₃-CO-H₂-CH₄-O₂-H₂O-N₂ systems were investigated. The experiments were carried out using a flow reactor under the atmospheric pressure at 850°C. The various compositions of the inlet gases employed were 500 or 1000 ppm NH₃-0 or 500 ppm NO-0∼10% CO-0∼5% H₂-0∼5% CH₄-0∼3% O₂-0∼10% H₂O-N₂ and the mean residence t i m e in the flow reactor was 0.37 Ns. And, the following results were obtained:
(1) CH₄ remarkably inhibited denitrification (removal of NH₃ and NO) and the higher the concentration, the higher was the optimum air ratio which gave the maximum of fraction al denitrification.
(2) CH, remarkably inhibited oxidation of both CO and H₂, where the formation of OH, O, H radical decreased. Consepuently, denitrification, which occurred by way of the reactions with these radicals, was inhibited.
(3) The optimum air ratio was affected by the concentration of the coexisting gases as well as CH₄. And, the extent of the effects was in the following order, . CH₄>NH₃>H₂>H₂O>CO>NO

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Permeabilities of some polymer solutions in a reverse osmosis process have been examined by using cellulose acetate membrane. The separation degree of each polymer solute was more than 99%, and the solution flux (Jv) was apparently lower than the pure water flux (Jw)The order of JvjJ, was obtained and the polymers were classified into the following three types according to the relationship between Jv/Jw and the polymer concentration:
In the case of type (1), Jv/Jw depended on the polymer concentration, and a polymer gellayer was formed upon the membrane. In the case of type (2), Jv/Jw as about 0.8 and did not show any significant dependence on the polymer concentration. In the case of type (3), the gel-layer was formed little and Jv/Jw as nearly equal to 1.0, although the viscosities of the solutions were very high.
The formation of gel-l ayer was assumed to control the flux, and it was found that the hydrophobic polymer formed gel-layer more easily; Jv of MC or PVP solution increased by the addition of sodium dodecylsulfate. Based on these facts, it was assumed that the hydrophobic bond between the polymer solute and cellulose acetate membrane had an influence on the formation of gel-layer.

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The volatilization behavior of toxic heavy metals in the residues discharging through the Resoruce Recovery System (RRS) of the municipal wastes was experimentally studied in order to examine the possible secondary pollution induced by the light-weight aggregates production process by utilizing the RRS residues. The RRS residues consist of selected inorganics and pyrolytic dust, and contain toxic metals as shown in Table 1. The pellet was made of the residues and was used for the volatilization experiment.
The volatilizing behavior was examined by using an apparatus shown in Fig.1 under various experimental conditions. It was found that the volatilization of Cd and Pb existing in the residues increased with the rising temperature, and was strongly influenced by carbon content of the pellet, oxygen concentration and velocity of the flowing gas, and increased under a reduced atmosphere as shown in Fig.4 and 5. The Cd and Pb oxides existing in the RRS residues may be reduced by reductive substances generated by thermal decomposition and partial oxidation of carbonaceous materials in the pellet. It is considered that the increase of Cd and Pb volatilization under the reduced atmosphere is ascribed to the increase of metal fraction since the vapour pressures of the Cd and Pb metals are higher than those of the oxides in the temperature range of this experiment.

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Activated carbons were produced from five kinds of waste phenolformaldehyde (PF) resins by the steam activation. The specific surface area of an activated carbon made from a most commonly used PF resin (sample A) reached more than 1000 m²/g in about 25% yield. The amounts of benzene and methanol vapors adsorbed on the activated carbon were much larger than those adsorbed on a commercial carbon (Figs.8, 9). The amount of phenol adsorbed from the dilute aqueous solution on the activated carbon was comparable to that of another commercial carbon (Fig.10). The specific surface areas of activated carbons produced from other two PF resins (samples B and C) were also comparable to those of an activated carbon produced from the Miike coal (Fig.6).
The activated carbon made from sa mple A was rendered to the repeated cycles consisting of adsorption of waste water and thermal regeneration. Although the specific surface area and the adsorption capacity of the activated carbon decreased with an increase of the number of the cycle, the extents of the decrease were similar to those of a commercial carbon (CAL). Thus it was found that the activated carbons made from waste PF resins can serve for practical use.

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Catalytic conversion of acrylonitrile to acrylamide over copper-on-silica-magnesia was carried out in the liquid phase fixed-bed flow system at 80°C. Selective formation of amide with consatnt conversion of nitrile was observed over 70 h on stream. Kinetic data showed strong adsorption of amide, resulting in deviation from first-order kinetics. The catalyst was sensitive to oxygen, a slight amount of oxygen might decrease the catalytic activity. Oxygen. dissolved in the solvent water, whose concentration might be limited to a lower level in practical cases, changed the color of the catalyst bed gradually. By using oxygen-saturated and air-saturated water, during 360 h on stream, brownish yellow and dull black bands developed from the top to the end of the bed. Up to 200 h, the brownish yellow band (presumably Cu₂O ⋅n H₂O) was spread over the entire bed, and the conversion of nitrile increas ed without a decrease in selectivity to amide. In further 160 h, the catalytic activity degenrated, and it might be attributed to the growth of a black band (presumably CuO) from the top of the bed. Regeneration of deactivated catalyst was successful by hydrogen reduction at 200∼300°C.

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The dechlorinating decomposition of CH₂Cl₂ was studied with a micro-autoclave (10 ml volume) under alkaline hydrothermal conditions. The transition process of the dechlorinating products to spherical carbons was followed by a scanning electron microscope. It was found that the formation of the spherical carbons resulted in the spherical aggregation of initial dechlorinating products (needle crystals) at 200°C. The neat and uniform globular ca rbons were produced under conditions of a low alkaline content (below the equimolar ratio of [Na]/[C1]) at 300°C. The size of these spherical carbons was ca.2∼3μ m. The spherical ca rbons formed under conditions of a high alkaline content were of various sizes.

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In order to remove [Fe (CN)₆]^3- and [Fe (CN)₆]^4- from waste water as insoluble zinc hexacyanoferrate (II) the reduction of [Fe (CN)₆]^3- (0.641 × 10^-3mol/l) at room temperature in the presence of zinc sulfate (2.5 times the molar quantity of [Fe (CN)₆]^3-) was compared with that in the absence of it at pH 6.4∼6.6 with seven kinds of reducing agents.
It was found that zinc ion greatly accelerated the reduction of [Fe (CN)₆]^3- with relatively small amounts of reducing agents (1∼2 times the molar quantity of [Fe (CN)₆]^3-) when sodium sulfite, sodium disulfite, hydroxylammonium chloride, hydrazinium sulfate, sodium dithionite, or sodium thiosulfate was used. Thus, the formation of zinc hexacyanoferrate (II) was almost complete within 30 min (sodium thiosulfate) or several minutes (the other reducing agents), and the residual cyanide concentration in the filtrate was < 0.1ppm. t Studies on the Treatment of Waste Water Containing Iron Cyanid e Complexes. I.

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