Osmometric studies on the state of solution of mixtures of rust inhibitors have been made. Mixtures of rust inhibitors investigated here have been found to dissolve in oils forming various mixed micelles.
The degree of interaction of sodium dinonylnaphthalene sulfonate with other rust inhibitors is in the following order:
Potassium abietate>Duomeen-T dioleate>Pentaerythritmonoisostearate>Lead naphthenate
The degree of interaction of sodium dinonylnaphthalene sulfonate with lead naphthenate in hydrocarbon solvents increases with the decrease in the solubility parameters of the solvents due to the enhancement of the solute-solute interaction of the dual solutes.
The activity of mixtures of rust inhibitors in the commercial rust preventive oils decreases by the formation of mixed micelles.

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Comparative studies on the vapor phase and liquid phase oxidation of ethylene were made with palladium chloride-active charcoal catalyst. The catalyst activity in the vapor phase reaction was higher than that in the liquid phase reaction. Acetaldehyde was obtained with high selectivity in both phases. The rate of acetaldehyde formation in the vapor phase was accelerated by the increase in steam pressure and was suppressed by the rise in the reaction temperature while the rate in the liquid phase reaction was accelerated by the rise in the reaction temperature. Aqueous hydrogen chloride solution of about 0.1N was effective as a reaction medium to keep the catalyst activity constant. Contrary to the vapor phase reaction the rate in the liquid phase reaction decreased with the increase in partial pressure of oxygen.

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An investigation has been carried out to obtain information about the effect of quenching on ethylene decomposition in the induction-coupled argon plasma jet at 1 atm. The quenching of the decomposed products was made by a small water-cooled silica tube. The lowering of the quenching temperature due to the increase in the distance between the inlet of the small silica tube and the induction coil increased the selectivity of acetylene formation on carbon base, but at the same time, the increase in the distance changed the conditions of mixing of ethylene with the plasma jet flame. The increase of the inside diameter of the small silica tube with a given outside diameter also yielded acetylene more selectively due to the drop in the quenching rate. Furthermore, it was suggested from the products distribution that the quenching of the decomposed products occurred at higher temperatures as the flow rate of argon increased. Deviation from thermodynamic equilibrium of the carbon-hydrogen system for composition C/H=0.5 increased with the increase in the distance between the inlet of the small silica tube and the induction coil and with the lowering of argon flow rate.

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In order to elucidate the effect of X_nO_m on the catalytic activity and selectivity, vapor phase oxidation of butadiene and isomerization of 1-butene were carried out in air over a series of Mo-P-X (1:0.2:0.1 atomic ratio) oxide catalysts in which component X was varied over a wide range. Oxidation and isomerization activities were compared with the dehydration activity on isopropyl alcohol that was used as a measure of acidity of the catalysts. A good proportional relationship was obtained between dehydration activity and oxidation activity as well as isomerization activity. The change in the reaction-order of butadiene oxidation was also interpreted in terms of the acidic property of the catalyst. The selectivity of butadiene to maleic anhydride increased clearly by the addition of a third component, but the relationship between selectivity and acidic property was not clear.

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Catalytic hydrocracking of cresols was investigated to elucidate the effect of catalyst carrier on demethylation and dehydroxylation rates. Conventional flow reactor made of quartz was used. The experimental reaction conditions were as follows; temperature 350∼380°C (for CoO-MoO₃ supported on Al₂O₃) and 450∼530°C (for NiO supported on MgO), LHSV 1∼6hr^-1, H₂/ cresols 2∼18mol/mol. Primary cracking reactions were demetkylation and dehydroxylation; disproportionation and isomerization reactions were also detected in the advance stages of hydrocracking. CoO-MoO₃ supported on Al₂O₃(cat-A) favoured dehydroxylation over demethylation and NiO supported on MgO(cat-B) favoured demethylation over dehydroxylation. Disproportionation and isomerization reactions were more pronounced by cat-A than by cat-B. Products detected were phenol, toluene, 2, 6-dimethylphenol, 2, 4-dimethylphenol and m-, p-xylenes. Kinetics was correlated using a conventional Langmuir-Hinshelwood model. The model was first order with respect to cresol, and the reaction mechanism based on carbonium ion complex formation was suggested.

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The catalysis of bismuth nitrate in the autoxidation of olefins has been kinetically investigated. The rate of oxidation is the second order with respect to the concentration of olefins and a half order to the concentration of bismuth nitrate. It was also confirmed kinetically that bismuth nitrate does not decompose hydroperoxide to free radical during the reaction. From consideration of calculated rate constants of initiation step for several olefins, the rate determining step for the initiation of oxidation has been concluded to be an electrophilic reaction, and a new mechanism of the initiation has been proposed.

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Adsorptive properties of LaY zeolite for some aromatic hydrocarbons and ethylene were investigated by a gas chromatographic method. With the pretreatment temperature of LaY being risen, the retention volume of aromatics increased, whereas that of ethylene decreased. Though the heat of adsorption of benzene slightly increased with the pretreatment temperature, that of ethylene was substantially independent of the thermal treatment of LaY. A linear relationship was found between the decrease in the ionization potential of aromatic hydrocaronbs and the increase in the heat of adsorption.
Catalytic properties of LaY for the alkylation of benzene with ethylene were also investigated by means of a flow system. The pretreatment temperature being increased, the initial rate of alkylation sharply decreased. On the other hand, the apparent activation energy of the reaction was not affected by the thermal treatment of LaY.
From these points of view, it is deduced that ethylene is adsorbed on the Brönsted acid sites of LaY to form the carbonium ion which acts as a reaction intermediate of alkylation. On the other hand, benzene seems to be adsorbed on the Lewis acid sites to form a charge transfer complex.

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The catalytic activities of Cu-Cr₂O₃-ZnO and Cu-ZnO systems for vapor phase condensation of 2-propanol were studied. The reaction was carried out by a flow method under the conditions of atmospheric pressure and LHSV=2hr^-1. The surface area and grain size of metallic copper on the used catalysts were measured by carbon monoxide adsorption and X-ray diffraction methods, respectively.
As the reaction products, higher ketones such as 4-methyl-2-pentanone (MIBK), 2, 6-dimethyl-4-heptanone (DIBK) and 2, 6, 8-trimethyl-4-nonanone (TMN) were obtained in high yield at about 250°C in addition to acetone which was thought to be an intermediate compound to above ketones.
The catalytic activity for condensation was considered to be caused by the existence of metallic copper on the catalysts and therefore, a higher total yield of condensation products was obtained by using a catalyst with larger surface area of copper on it.
Catalysts which contain larger amount of copper, have larger grain size of metallic copper, but no exact correlation between grain size of copper and the catalyst activity was found.
When 2-propanol was passed over the three-component catalyst with atomic ratio of Cu:Cr:Zn=0.5:1:1 at 255°C the highest activity for condensation was obtained, namely, yields of MIBK, DIBK and TMN were 29%, 27% and 13% (based on 2-propanol fed), respectively.

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Tokuyama Soda has developed a new process for direct hydration of propylene to isopropanol in liquid phase. This process employs a highly active and selective catalyst system which essentially comprises an aqueous solution of polytungsten compounds within a selective pH range.
The first commercial plant, having a capacity of 30, 000 metric tons of isopropanol per annum, has been successfully in operation since the beginning of June 1972 at Tokuyama Soda Co., Ltd.
The features of the process are simpleness, low value for propylene consumption and freedom from environmental pollution problems. These advantages make Tokuyama Process by far more economical than the conventional process for the manufacture of isopropanol.

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Selective hydrogenation of butadiene to remove the butadiene from C₄ hydrocarbon fraction has been studied over palladium-alumina catalyst at elevated pressure. The following results were obtained.
(1) Presulfiding of the catalyst and presence of sulfur compounds in the reaction system were required to increase the selectivity of hydrogenation when butadiene content in C₄ fraction was relatively high (>1.0%).
(2) It was found to be effective that presulfiding of the catalyst by hydrogen sulfide was carried out under low temperature in order to gain high hydrogenation selectivity.
(3) Complete removal of butadiene without n-butenes loss was achieved from the studies on the reaction conditions. Activity and selectivity of the catalyst were preserved constantly during long run test.
(4) Isomerization of 1-butene accompanied with hydrogenation was retarded by the presence of butadiene. Complete isomerization of 1-butene to 2-butene needed more severe conditions than complete removal of butadiene hydrogenation.
(5) Palladium-alumina catalyst sulfided by hydrogen sulfide showed relatively strong resistance against the poison. In the presence of some gaseous inorganic compounds such as CO, Cl₂, COCl₂, N₂O, N₂O₃, and SO₂, selectivity of the hydrogenation increased. Moreover, CO completely depressed the isomerization of 1-butene.

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Selective hydrogenation of butadiene in C₄-hydrocarbon fraction in the presence of carbon monoxide in order to remove the butadiene and to prevent the isomerization of 1-butene has been studied. The following results were obtained.
(1) The sensitivities of metal-alumina catalysts to carbon monoxide varied in order of Fe>Pt>Co>Pd>Ni. The selectivities of butadiene hydrogenation in the presence of carbon monoxide were almost quantitative over Pd, Co and Ni catalysts and somewhat low over Pt catalyst. The order of the magnitude of prevention effects for 1-butene isomerization by carbon monoxide was Pd>Ni>Pt∼Co. Consequently, Pd-alumina was found to be most favorable catalyst in the selective hydrogenation of butadiene without 1-butene isomerization in the presence of carbon monoxide.
(2) Reaction conditions over Pd-alumina catalyst were investigated. Higher pressure and carbon monoxide concentration were effective for the prevention of 1-butene isomerization. Complete removal of butadiene was possible in the lower range of the pressure and carbon monoxide concentration than the prevention of 1-butene isomerization. Higher temperature was preferable to raise hydrogenation activity, whereas lower temperature was desired to prevent 1-butene isomerization. Optimum temperature was found to be nearly in 100°C, and about 90% of residual 1-butene and the complete removal of butadiene were achieved simultaneously at this temperature.
(3) The action of carbon monoxide to the Pd catalyst in the hydrogenation was reversible. The hydrogenation selectivity and residual 1-butene in the product varied rapidly by addition or removal of carbon monoxide.

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Selective hydrogenation of butadiene to prepare 1-butene in a good yield has been studied over several group VIII metal catalysts in the presence of carbon monoxide. The following results were obtained.
(1) In the presence of carbon monoxide, the selectivities of butadiene hydrogenation to n-butenes were kept nearly 100% until high conversion of butadiene over the various metal catalysts.
(2) The selectivities of 1-butene and the trans-2-butene/cis-2-butene ratios did not change with the variation of the butadiene conversion over various metal catalysts and the selectivities of 1-butene over these catalysts were rebresented in the following order: Pt>Ir>Ph∼Ru>Pd>Ni and the order of trans-2-butene/cis-2-butene ratios were Pd>>Ir>Ni>Ru∼Ir>Pt. It was considered that 1-butene and 2-butenes were formed only by 1.2- or 1.4-addition of H₂ on butadiene and the isomerization of 1-butene to 2-butenes did not proceed until butadiene disappeared.
(3) Platinum-alumina catalyst showed very high 1-butene selectivity but resulted 1-butene was isomerized to 2-butenes when the butadiene conversion exceeded 90%. On the other hand, palladium-alumina catalyst showed somewhat lower 1-butene selectivity but no isomerization was observed. As a result, 1-butene could be produced in a good yield from butadiene using platinum-alumina catalyst followed by palladium-alumina catalyst in the presence of carbon monoxide in H₂.

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