This paper describes the kinetic treatment of oxidation of squalane at 60∼120°C.
Di-tert-butyl peroxide (DTBP) and 2, 2'-azobisisobutyronitrile (AIBN) were used as initiators and chlorobenzene was used as an inert solvent.
The values of k_p/(2k_t)^1/2 in the neat phase are slightly less than those in chlorobenzene solution for a given initiator concentration and temperature. This retardation can be attributed to the solvent effect of chlorobenzene on the decomposition rate of DTBP, since the correction of the solvent effect eliminates the decrease in k_p/(2k_t)^1/2. The values of first-order term "aRi" were calculated from the data, and the values of "a" were found to be 0.77 and 0.65 at 60 and 95°C, respectively, instead of 0.50, which was predicted by simple oxidation scheme.
The kinetic order with respect to the initiation rate is 0.57 at 95°C instead of the theoretical value of 0.50 both in the neat phase and in chlorobenzene solution.
The values of activation energy (E_p-E_t/2) are obtained as 11.6kcal/mole and 14.3kcal/mole in chlorobenzene solution and in the neat phase, respectively, on the assumption that the decomposition rate of DTBP in the neat phase is the same as that in chlorobenzene solution. The correction of the solvent effect also eliminates the difference in both values.
The solvent effect on the decomposition rate of DTBP plays an important role especially in the initiated oxidation of aliphatic hydrocarbons.

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The activation volume of viscous flow in mixtures of paraffinic and naphthenic base oils of high and low viscosities, and in those of liquid fatty acids, their esters, and fatty oils have been determined experimentally. The results are used to test the applicability of the semiempirical formula which can estimate the activation volume from the molecular structure of the substance involved. Limitations in its applicability are also discussed.

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The isomerization of pentanes in the presence of hydrogen was investigated in a flow system at total pressure ranging from 1 to 50atm and temperatures from 270 to 330°C on platinum/rare earths-hydrogen-zeolite Y catalysts. Platinum was introduced into the zeolite by ion-exchanging it with an aqueous solution of platinum ammine complex. The platinum contents of the catalysts were in the range of 0.05∼1.0wt%. It was observed that isomerization of n-pentane to isopentane and that of isopentane to n-pentane were accompanied with disproportionation to hexane and butane isomers, hydrogenolysis to lower molecular weight paraffins, and isomerization to neopentane. Based on such effects as the Pt content, the treatment of the catalyst with steam and the reaction conditions, and also based on kinetic considerations, the four reactions were considered to proceed through the following scheme. Several factors that influence the isomerization selectivity to isopentane were summarized. Finally, the mechanism of isomerization of pentanes was discussed on the basis of the present experimental results.

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In order to obtain active catalysts for low-temperature steam-reforming of hydrocarbons, experimental studies have been carried out using various catalysts which consist of a noble metal and a support containing WO₃.
Experimental results have shown that Rh-MgWO₄ exhibits an outstanding catalytic actiaity (more than 70% conversion of n-heptane at 500°C and at S. V.=10⁴hr^-1) despite the fact that MgWO₄ consists of developed crystallites and it has a very small surface area (3∼5m²/g). Other tungstates, i. e. BeWO₄, ZnWO₄, CaWO₄ and BaWO₄ have shown much inferior supporting properties for Rh than MgWO₄. The superior supporting property of MgWO₄ suggests a special role of Mg²⁺ ion in the catalyst support.

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The reaction between benzene and steam on potassium polyaluminate catalysts was investigated in a flow system under atmospheric pressure at 900°C. The catalytic activity increased with increasing K⁺ content in the catalyst, showing that the potassium cation constituted the active sites for this reaction. The rate of reaction between the deposited carbon and steam also increased as the K⁺ content increased. A good linear relationship was obtained between activity and the rate of the carbon-steam reaction.
The conversion of benzene to carbon monoxide and dioxide and the amount of deposited carbon decreased with increasing partial pressure of steam, while both of them increased with increasing partial pressure of benzene. The depression with steam was explained by the competition of the steam with benzene for the active sites, resulting in retardation of the formation of intermediate deposited carbon.

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The catalytic activity and selectivity of Group VIII transition metals, except Os and Ir, supported on graphite for hydrocarbon synthesis from mixtures of carbon monoxide and hydrogen were investigated under atmospheric pressure at 300∼400°C. Methane was the main reaction product on all these catalysts. Some of the catalysts, however, exhibited considerably high selectivity for production of C₂ or higher gaseous hydrocarbons. The following sequence of selectivity for C₂ hydrocarbons was obtained: Fe>Pd>Rh>Ru>Pt>Co>Ni. Among the catalysts tested, the graphite-supported Rh catalyst showed the highest rate of production of C₂ hydrocarbons.
In the whole ragne of conversions, the graphite-supported Rh catalyst produced C₂ hydrocarbons more selectively than the alumina-supported or charcoal-supported catalysts. This difference was considered due to the strong metal-support interaction in the graphite-supported catalyst that involved electron transfer between rhodium and graphite.
Among the various pretreatments rendered using different gases, pretreatment in air enhanced most the activity of the graphite-supported Rh catalyst.

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Two different kinds of vacuum gas oils have been hydrodesulfurized and hydrogen consumption has been measured by means of three procedures. It has been proposed that the convenient procedure based on the measurements of the changes in aromatic carbon content in the oil by n-d-M analysis is sufficiently applicable to the measurements of hydrogen consumption.
Reaction kinetics has also been studied, and the apparent reaction order has been found to vary with change in the reaction temperature.

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The vapor-phase reaction of cyclopentadiene (CPD) with acetylene over silicon carbide has been investigated with reference to the formation of 2, 5-norbornadiene (2, 5-NBD) and toluene. The yield of 2, 5-NBD was enhanced with rise in the reaction temperature and showed a maximum yield at 420°C. On the other hand, the formation of toluene initiating at 400°C increased with increasing temperature and with a simultaneous decrease in the yield of (2, 5-NBD). At 550°C, the yield of toluene was 30% and the selectivity was 75%. The formation of toluene was also observed in the reaction of 2, 5-NBD. Therefore, it was concluded that 2, 5-NBD was an intermediate of toluene. This was consistent with the kinetic studies on the formation of toluene. The menchanism of the addition of acetylene to CPD was also discussed and as a result, the role of a radical mechanism, in addition to that of a concerted one, was also assumed.

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tert-Butylation of aromatic hydrocarbons with tert-butyl chloride in the presence of AlCl₃-tert-butylanisole was investigated. Neither isomerization of the products nor transalkylation of the substrate with the products was observed when the molar ratio of tert-butylanisole to AlCl₃ was more than two. Competitive tert-butylation of benzene and toluene showed higher substrate selectivity (k_T/k_B=21-24). A role of trans-tert-butylation in the tert-butylation was suggested from the results of tert-butylation of toluene in the presence of 2, 4- and 2, 5-dimethylanisole.

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The liquid phase disproportionation of propylene and 1-butene over MoO₃-Al₂O₃ catalyst was carried out in a conventional flow system at 80°C under 50kg/cm² to elucidate the effect of addition of metal oxides to MoO₃-Al₂O₃ as well as the solvent effect of paraffins, aromatics, and naphthenics.
By the addition of Cs₂O and Tl₂O to MoO₃-Al₂O₃ catalyst, the selectivity for disproportionation of olefins increased, showing a tendency similar to that in the gas phase disproportionation reactions.
In the presence of linear hydrocarbon solvents, the catalyst life was remarkably enhanced. This tendency was especially intensified in the presence of n-heptane. Disproportionation of propylene in the presence of aromatic or naphthenic hydrocarbons could not be continued for a long time because of the flow resistance in the reactor. In the case of aromatic solvents, large quantities of alkylbenzenes were produced. Infrared spectra of the polymers produced in the presence of various solvents showed absorption bands due to the carbonyl groups. These absorption bands may have resulted from the oxidation of the polymers by the oxygen of the MoO₃-Al₂O₃ catalyst. It is concluded that the reactions in the presence of linear hydrocarbon solvents are prevented from extensive formation of polymers with higher molecular weights.

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The probability of acetic acid synthesis from n-butenes and isobutene was studied with V₂O₅-binary catalysts. As a second component, following atoms were added to V₂O₅ in the form of oxide or metal; Rh, B, Cr, Nb, Zn, Pd, Ta, Zr, Si, Ni, Ge, Fe, Ca, Pt, W, Li, Cd, As, Co, Te, Mg, Mn, Mo, Cu, Ag, P, Ba, Ti, Sn, Al, and Sb.
In the presence of water, n-butenes and isobutene were oxidized to acetic acid with more than 40% selectivity based on the carbon atom at about 100% conversion of each butene with air containing 3% of butene over V-Cr(3/7), V-Rh(8/2), V-B(5/5) and V-Nb(5/5) catalysts at 270∼310°C.
Acetaldehyde, acetone, formaldehyde, maleic acid, formic acid, propionic acid, acrylic acid and citoraconic acid were obtained in low yields from n-butenes.
On the other hand, from isobutene methacrylic acid and isobutylic acid were formed in addition to above by-products in low yields.
As to the reaction path, acetic acid was considered to be formed via hydration of butenes to form an alcoholic intermediate¹⁾), followed by oxydehydrogenation on the catalyst which had some different active sites to induce other reactions at the same time.

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Alumina FE (fibrous powder containing no sodium) and alumina FF (fibrous fine particles with small bulk density) were synthesized, and their surfaces and catalytic properties were studied. Both fibrillar aluminas were found to have high acid strengths and large amounts of oxidizing and reducing sites compared with gibbsite aluminas.
For the isomerization of 1-butene, only Al₂O₃ FF showed no decrease in activity, and the selectivity (the ratio of cis-2-butene to trans-2-butene) was 1.6. In the reaction of propylene oxide, Al₂O₃ FE produced a larger amount of propion aldehyde compared with a gibbsite. On the other hand, Al₂O₃ FE predominantly formed ketone in the reaction of 1-methylcyclohexene oxide, while Al₂O₃ FF formed allyl alcohol predominantly. For the alkylation of phenol with methanol, Al₂O₃ FF was more active than Al₂O₃ FE, and it formed a larger amount of anisole than an activated alumina. For the hydrocracking of thiophene, MoO₃ CoO mounted on a fibrillar Al₂O₃ was much more active than the same catalyst mounted on Al₂O₃ prepared by homogeneous precipitation.

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After the addition of potassium chloride (90g) and of various amounts of ferrofluid (0.5∼4.0ml) to 3, 000ml of a kerosene-in-water emulsion containing 1, 000ppm of kerosene, it was treated magnetically in a magnetic field of 462, 871 and 1, 480 Oe. The flow rate of the emulsion was varied from 100 to 600ml/min. The effects of the amount of ferrofluid added, the magnetic field and the flow rate of emulsion on the oil removal efficiency were studied. As a result, the oil removal efficiency increased as the amount of ferrofluid added and the strength of magnetic field increased, but it decreased as the flow rate of emulsion increased. Ferrofluid is a stable colloidal dispersion of magnetic particles (D<150Å) whose carrier liquid is kerosene.
An equation for oil removal efficiency was theoretically derived. The calculated and measured values of oil removal efficiency are shown.

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