Pentaerythritol partial-esters were synthesized and their physical properties, thermal stabilities, heat of adsorption, and lubricity were investigated. It was found that the hydroxyl groups involved in the partial-esters exerted some important effects on their properties. The partial-esters showed higher viscosities than their respective full-esters due to the association of their molecules. They adsorbed strongly onto metal surfaces to control corrosion of the metals, and to give better boundary lubricity.

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Activation volume of viscous flow was investigated with twelve mineral lubricating oils of different molecular types. The activation volume was derived experimentally from the change of kinematic viscosity for pressures from 1 to 300atm at 25°C. A semi-empirical formula was proposed to evaluate the activation volume based on the segment flow theory. The activation volume was calculated by averaging the segmental activation volumes assigned to the aromatic ring, the naphthenic ring, and the paraffinic chain. The estimated activation volume was in good agreement with the measured value within the accuracy of several percent.

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The dehydrosulfurization of ethanethiol over various alkali metal zeolite catalysts was studied. The catalytic activity of NaY zeolite was little affected by the exchange of sodium ion with other alkali metal ions (Li, K, Cs and Rb). The catalytic activity of sodium zeolite was dependent on the types of zeolite (NaX, NaY and NaA), and the order of its catalytic activity was NaX>NaY>NaA. When NaY and NaA were used, the dehydrosulfurization products were only ethylene and hydrogen sulfide. In the case of dehydrosulfurization of ethanethiol on NaX, the products were ethylene, hydrogen sulfide and a substantial amount of diethyl sulfide which was formed by disproportionation of ethanethiol. Furthermore, discussions were made on the active sites of alkali metal zeolite catalysts, and it was concluded that they were the alkali metal ions and the oxygen anion of skeletal structure of zeolite. In the light of the nature of the active sites, the reaction mechanisms were also proposed.

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In order to clarify the active species of MoO₃-Al₂O₃ catalyst for hydrocracking of diarylmethane, the effects of MoO₃ content and calcination temperature on catalytic activity were studied. Moreover, changes in the hydrocracking behavior of diarylmethane over pretreated catalysts with water and aqueous ammonia were investigated.
The catalytic activity increased with increasing MoO₃ content, calcination temperature, and reduction time. Molybdenum oxide, which is extractable with aqueous ammonia but not extractable with water, was favorable for hydrocracking reaction.
These results were well correlated with Giordano's study¹⁾. It was suggested that the main active species for hydrocracking were weak acidic sites formed by the reduction of octahedral Mo(VI) interacting with Al₂O₃.

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A series of nickel catalysts supported on silica-alumina was prepared for hydroalkylation of aromatic hydrocarbons and effects of pretreatment of catalysts and reaction conditions on their catalytic activity were studied. The selectivity of cyclohexylbenzene which is obtained by hydroalkylation of benzene correlated to the surface acidity of silica-alumina support. The most suitable catalyst was nickel (3∼5wt%) supported on silica-alumina (alumina content: ca. 42wt%), and the results obtained with this simple catalyst were compared with those obtained with catalyst of nickel on a silica-alumina carrier containing both tungsten and fluorine reported by Slaugh et al.
The molar ratio of cyclohexylmethylbenzenes to cyclohexylbenzene formed by the reaction of equimolar mixture of benzene and methylbenzenes increased with increase in the basicity of the methylbenzenes.

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The alkylation of phenol with cyclohexene in the vapor phase has been studied over the cation-exchanged X zeolite catalysts. Because of the dealkylation of products, the catalytic activity decreased with rising reaction temperature. The yield of cyclohexylphenol increased linearly with increase in the amount of acid. Furthermore, the catalytic activity decreased by the addition of pyridine. However, the order of catalytic activity for alkylation of phenol with cyclohexene was not in accord with that for the cracking of cumene. On the other hand, the volcanoshape relation was observed between the catalytic activity for alkylation of phenol with cyclohexene and the electronegativity of metal ion in the catalyst. On the basis of these results, it is concluded that the alkylation reaction proceeds on the acid sites, and the active sites are the surface protons and the metal ions of the catalyst.

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Oxidation reactions of ethylene over zeolite loaded with Pd(II) and/or Cu(II) by way of ion exchange were studied in the presence of steam. Neither Pd(II)-zeolite nor Cu(II)-zeolite had good catalytic activity for oxidation of ethylene to acetaldehyde. However, the dual ion catalysts, namely, Pd(II)-Cu(II)-zeolites which were prepared by various ion exchange methods, were found highly active and selective for oxidation of ethylene to acetaldehyde. The degree of conversion of olefins under the same experimental conditions was in the order: ethylene>propylene>1-butene>cis-2-butene≈trans-2-butene. The reaction mechanism was discussed in analogy with that of Wacker-reaction.

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A new type of benzylic oxidation of toluene in vapor-phase was described in which toluene was dehydrodimerized to bibenzyl and stilbene over Bi₂O₃-SnO₂, catalyst in the temperature range 400∼600°C. Effects of temperature, contact time, and oxygen-to-toluene ratio were investigated in detail, and a proposal of reaction scheme was made.
The results obtained show that reactions with longer contact time and higher oxygen-to-toluene ratio are favorable to the formation of stilbene, while shorter contact time and lower oxygen-to-toluene ratio favor the formation of bibenzyl. A reaction route for the formation of stilbene consistent with these data involves the following consecutive steps; toluene→benzylic intermediates→bibenzyl→stilbene. This type of benzylic oxidation is considered to be analogous to the oxidative dehydroaromatization of C₃-C₄ olefins.

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The vapor-phase oxidation of 1-butene, butadiene, and acetic acid were carried out in the presence of excess air over two series of V₂O₅-K₂SO₄-H₂SO₄ catalysts, V₂O₅-K₂SO₄-H₂SO₄ (2-x-1, mole ratio) and V₂O₅-K₂SO₄-H₂SO₄ (2-1-y) where x and y were varied (X=0∼1.0, y=0∼3), and the relationship between catalytic behavior and acid-base properties of the catalysts was investigated. The acidity and basicity of V₂O₅-K₂SO₄-H₂SO₄ catalysts were obtained from the values of dehydration activity for isopropyl alcohol (IPA), r_p, and the ratio of (dehydrogenation activity for IPA)/(dehydration activity for IPA), r_a/r_p, which were measured in the presence of excess air. It has been found that the acid-base properties of the catalysts are changed largely by the contents of K₂SO₄ and H₂SO₄, and that oxidation activity and selectivity can be interpreted in terms of the acid-base properties of the catalysts. It can be concluded that the acid-base conception in which the catalytic activities are governed by the acidbase properties between the catalyst and reactant is still effective in explaining the function of the K₂SO₄ and H₂SO₄ added to V₂O₅.

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Acid strength and acidity of Mo-X (alkaline earth metal)-As oxide catalyst have been studied and discussed in connection with catalytic activity in vapor phase oxidation of 1-butene. The activity test was carried out at about 470°C, with 17% olefin in air. Acid strength and acidity were determined by the amine titration method with the set of Hammett indicators, in the range of -5.6<pKa<7.1
The acidity of Mo-Ba oxide is decreased remarkably by addition of As componen to the binary oxide, although As oxide has high acidity, especially in the range of strong acid strength, and the resultant Mo-Ba-As oxide has acidity of weak acid strength. A comparison of activity with acidic property of Mo-X-As (atomic ratio=1:1:1) type oxide catalyst containing different kinds of X component and Mo-Sr-As (As/Mo=1) oxide catalysts of different amounts of Sr showed that butadiene formation (partial oxidation) and 2-butene formation (isomerization) increased with increasing acidity in weak acid strength (1.5<pKa<7.1, while CO₂+CO formation increased with increasing acidity in strong acid strength (pKa<1.5).
It is considered that molybdate of alkaline earth metal exists in both Mo-X and Mo-X-As oxides, and plays important roles in the catalytic oxidation reaction. However, the coexistence of As component suppresses the crystallization of this salt, resulting in the decrease of isomerization and increase of selectivity for partial oxidation. By increasing atomic number of X component in Mo-X-As oxide catalyst, acidity and the activity for diene formation decreased but the selectivity for the formation increased. Propylene oxidation was also studied with regard to the acidic property of the catalyst.

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The addition reaction of carbon monoxide with ethyl iodide in aqueous hydroiodic acid was investigated under high pressure in the range of 30 to 90kg/cm². The yield of propionic acid was fairly high and the rate of formation was the first order reaction with respect to carbon monoxide and ethyl iodide. The overall activation energy has been found to be 13.0kcal/mole, which contains the molar enthalpy change of equilibrium reaction (2), i. e., the heat of dissociation of C₂H₅I and the activation energy of reaction (3), i. e., the reaction between the ethyl cation and carbon monoxide.

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A new catalytic hydroboration of olefins in the gas phase has been proposed. The kinetics of the reaction of diborane with ethylene or propylene in the presence of a Pd-carbon catalyst was investigated at 30°C to 50°C The initial rate of the reaction, r_i, was expressed by r_i=kp^1/2_BP_O, where P_B and P_O denote the initial partial pressures of diborane and ethylene or propylene, respectively, and k the rate constant. The activation energy was 6 and 1.5kcal/mol for ethylene and propylene, respectively. These activation energies were much smaller than those for noncatalytic hydroboration found in literature. The reaction mechanism was interpreted in terms of the rate-determining step which is the attack of the olefin on the dissociated diborane on the catalyst. The reaction mechanism was further confirmed by the adsorptions of diborane, ethylene and propylene.

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In dehydrogenation of n-butane over alumina-chromia catalyst, a decrease in reaction rate with increase in time of reaction process is due mainly to the catalyst fouling caused by the accumulation of coke on the catalyst pellets. Such cyclic operation in which a catalytic reaction and catalyst regeneration are performed alternately is necessary from economic considerations. It is deduced from the experimental result that in a complete mixed type reactor the rate of coke formation is proportional to the mole fraction of n-butene in the reactor, and the time required for complete generation of the fouled catalyst is proportional to the total amount of n-butene produced. The objective functions are expressed in terms of the amount of n-butene produced, the time of reaction, and the time required for complete regeneration.
Criteria for predicting the optimum switching time are associated with maximizing the average production rate of n-butene, minimizing the direct production costs per mole of n-butene, and maximizing the gross profit in one cyclic operation. By expressing the desired substance in the reactor effluent in terms of its mole fraction, these criteria have the advantage in that the optimum switching time can be determined not by the activity of the catalyst, but by the mole fraction of n-butene in the effluent.

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Complete vapor-liquid equilibrium data were determined on the systems 2-methyl-2-butene-acetonitrile and isoprene-acetonitrile at elevated pressures, and partial vapor-liquid equilibrium data very near the azeotrope were determined under compressed nitrogen pressures. The Wilson equation was used to fit the experimental liquid phase activity coefficients, taking into account the vapor phase imperfections.
The pressure effect on the azeotropes formed for all systems was determined from the experimental data and represented by two sets of empirical equations.

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