On the isomerization of propylene oxide (PO) to propionaldehyde (PA) and/or acetone (AC) on five oxide catalysts (SiO₂, Al₂O₃, MgO, ZnO and CdO), mechanisms and selectivity-controlling factors of the isomerization were studied by the MOPAC-PM3 semi-empirical calculation method. The validity of the mechanisms proposed so far was discussed by comparison of activation energies for the isomerization of PO with experimentally determined selectivity on the five catalysts. It was found that PO isomerizes to PA on a metal ion (Lewis acidic site) and that the selectivity depends on the net charge of the site, i. e., the PA selectivity increases with the net charge of the site. Active sites adjacent to the Lewis acidic site, which are the metal ions in case of SiO₂, Al₂O₃ and MgO or the surface oxide ions in case of ZnO, are able to stabilize the reaction intermediate. It was concluded that the degree of the stabilization tends to increase as the bond length between the metal ion and the oxide ion decreases.
The isomerization of PO to AC, however, was estimated to proceed witho ut chemisorbing of the reactant on the surface of the catalyst.

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Partial hydrogenation of benzene was carried out with Ru catalyst-H₂O system in the presence of a small amount of alcohols. Ru/La (OH) ₃, Ru/γ-Al₂O₃ and fine Ru metal particle dispersed in the aqueous phase were used as catalyst for the hydrogenation.
The addition of alcohols to the reaction system decreased the reaction rate and increased the selectivity to cyclohexene, so alcohols worked as “co-catalyst” for the selective partial hydrogenation of benzene.
The enhancing effects on the selectivity were different among the alcohols, for example, in butanols, a primary alcohol (n-butanol) > secondary and tertiary butanols. Ally' alcohols and benzyl alcohol remarkably decreased the rate of the hydrogenation catalyzed by Ru/La (OH) ₃ and Ru/γ-Al₃O₃. When the fine Ru metal particle was used as the catalyst, a high selectivity to cyclohexene> 70% was obtained at 30% conversion of benzene by addition of a very small amount of benzyl alcohol.
It was assumed that these phenomena were caused by the change of electric character of the Ru surface by a lone pair of oxygen of alcohols. t Partial Hydrogenationo f Benz e ne. Part 2.

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Various types of bead-shaped starch ion exchangers were prepared from crosslinked bead-shaped starch which were produced by corn starch as starting materials. Diethyl-aminoethyl(DEAE) starch, 2-hydroxy-3-trimethylpropylammonio (HTMPA) starch and 2-hydroxy-3- {2- [bis (2-hydroxyethyl) amino] ethoxy}propyl (ECTEOLA) starch were prepared by the reaction of the basic materials with 2chloroethyl (diethyl) amine hydrochloride, (3-chloro-2-hydroxypropyl) trimethylammonium chloride and a mixture of 2, 3-epoxypropyl chloride (epichlorohydrin) and 2, 2', 2''-nitrilotrisethanol (triethanolamine), respectively. Their anion-exchange capacities and degrees of swelling were ≈2.47, ≈0.90, ≈0.48 meq/g and ≈6.6, ≈4.0, ≈6.7 cm³/g, respectively. Carboxymethyl (CM) starch, sulfome thyl (SM) starch and phospho (P) starch were prepared by the reaction of the basic materials with chloroacetic acid, sodium chloromethanesulfonate and phosphoryl chloride, respectively. Their cation-exchange capacities and degrees of swelling were ≈0.83, ≈1.70, ≈1.88 meq/g and ≈4.6, ≈3.7, ≈4.6cm³/g, respectively. The CM starch ion exchange beads obtained were found to be available as packing materials for ion exchange chromatography.

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The Michael type addition of primary amines to methyl acrylate in benzene was accelerated by alumina, and monoadducts were selectively obtained in high yield. The reaction in benzene did not proceed without alumina. The yields of adducts were dependent on the structure of amines; the monoa dducts were obtained in h igh yield (77-91% yield) when linear amines were used, and in the case of branched or bulky primary amines and secondary amines, the yields were decreased compared to the linear ones. In the addition of diamines to methyl acrylate, only anamino group on one side of the diamines added to methyl acrylate to give the monoadducts selectively, and the amino group on the another side did n ot react. In the addition of asymmetric diamine, the less hindered amino group predominantly reacted with methyl acrylate.

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Glycoluril-formaldehyde copolymer, obtained by the reaction of glycoluril with formaldehyde, is an insoluble compound in water and in most organic solvents. This copolymer can be converted into a macrocyclic compound named “cucurbituril” by further reaction.
In this study, we found that this copolymer effectively decolorized direct dyes and reactive dyes aqueous solution and that the decolorization efficiency was not only uninfluenced by temperature and pH, but also considerably better than that of cucurbituril. Mechanism of decolorization was investigated by using model compounds for the dyes.

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We prepared 29 N- (substituted phenyl) maleimides using following three methods; method A: using excess acetic anhydride, method B: using a stoichiometric amount of acetic anhydride, and method C: heating without solvent. The growth-inhibition activities of the maleimides were examined by the paper disk method against Escherichia coli (Gram negative), Bacillus subtilus (Gram positive) and a Gram positive marine bacterium. The maleimides had similar activities against Gram positive bacteria as a whole. The activities increased with the inductive electron-donating effect of the o-substituents of the N-phenylmaleimides against both Gram positive bacteria. We also examined the anti-adhesion activity in the sea of the maleimides against marine adhesive bacteria using the samples containing the maleimides in butyral resin. The anti-adhesion activity could be correlated with the growth-inhibition activity against B. subtilus.

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Dehydrochlorination rates of PVC were measured using an isothermal pyrolyzer and a thermobalance. A reaction model for the dehydrochlorination was developed on the basis of the isothermal pyrolysis data. From the Arrhenius plots of the reaction rate constants in this model, it was found that the kinetic parameters (the activation energies and the frequency factors) change at around 559 K. The kinetic parameters were divided into two groups at this temperature border. The calculated conversions of the dehydrochlorination using these parameters were compared with experimental values. Both experimental results of isothermal and non-isothermal reactions can be predicted by this model with some adjustments of the parameters according to the reaction conditions.

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A solution of copper (I) chloride-pyridine complex in acetonitrile was prepared by addition of pyridine to an acetonitrile suspension of copper (I) chloride under nitrogen. The solution of copper (T)chloride-pyridine complex in acetonitrile, 10 cm³, prepared from 10.0 mmol of copper (I) chlorid e, 40.0 mmol of pyridine, and acetonitrile rapidly absorbed carbon monoxide at 30 °C under 1.0 atm of carbon monoxide. The equilibrium amount of absorbed carbon monoxide was 5.90 mmol (59% against admitted copper (I) chloride). The absorbed carbon monoxide was rapidly released to gas phase by maintaining the solution at 70 °C under 1.0 atm. The amount of released carbon monoxide in equilibrium was 5.21 mmol (88% against absorbed carbon monoxide). The absorption-release cycle was repeated without any deterioration. The reversible absorption of carbon monoxide under mild conditions was attributed to formation of 1: 1: 1 copper (I) chloride-pyridine-carbon monoxide complex from carbon monoxide molecule and 1: 1 copper (I) chloride-pyridine complex in acetonitrile solution.

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The SO₂ poisoning phenomenon of supported palladium catalyst using ceria as oxygen storage materials was studied. Their surface states were measured before and after poisoning and examined sulfur desorption behavior. The desorption temperature of the sulfur adsorbed on Pd/CeO₂ was higher than that of Pd/Al₂O₃ in reduced condition, and gave an influence on regeneration. We suggest this was caused by the interaction between reduced palladium and ceria based on reducibility of ceria from an analysis of the sulfur quantity and chemical states change of catalyst. Also we studied the effect of a tmosphere on the SO₂ poisoning of Pd/CeO₂ at the fixed temperature. As a result, at 573 K adsorbed SO₂ would interfere the oxygen storage ability of Pd/CeO₂ in o xidizing condition and deactivate the surf ace of palladium in reducing condition.

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Carbon materials for mechanical sliders are usually manufactured from a blend raw material, which consists of pitch coke and carbon black to optimize the lubricating character and the resistance to wearing. However, in the production of the materials in commercial, scattering in the properties of carbons has been introduced by employing this technique, above all the scattering in the friction coefficient is a serious problem leading to a reduction in the product yield. In order to understand the factor determining the lubricating properties of mechanical carbon materials, eighteen carbon blocks were prepared in separate batches. Their properties including bulk density, Shore hardness, bending strength, and Young's modulus were measured and no correlation was found between the friction coefficient and these properties. The X-ray diffractograms of the samples were found to consist of two contributions, i. e. graphitic one and turbostratic one. Inspection of the relation between the friction coeffi cient and the fraction of the graphitic component calculated from X-ray diffractograms revealed a strong correlation between these two parameters. The frictional property of the carbon blocks containing carbon black and pitch coke was revealed to be mainly controlled by the presence of the graphitic component.

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