Retardation by trimellitic acid (TMA) and 4-methyl orthophthalic acid (MOA) of the main steps of the oxidation of pseudocumene with cobalt catalyst and methyl ethyl ketone activator in acetic acid was examined. The removal of these inhibitors from the oxidation system was also studied, and insoluble compounds containing TMA, MOA and cobalt were found formed by heat treatment of the filtrate of the reaction mixture.
The first order rate constants of dimethyl benzoic acid (DBA), 2-methyl terephthalic acid (MTA) and 4-methyl isophthalic acid (MIA) decreased linearly with increase in the TMA or in the MOA concentration.
Oxidation of DBA: k₂=1.12(1-0.53[TMA]/[Co]) (Figs. 2, 3)
Oxidation of MTA and MIA: k₃=1.80(1-1.43[TMA]/[Co]) (Fig 4)
It was confirmed that TMA coordinates with cobaltous ion and forms a 1:1 complex compound (Figs. 6, 7); however, its deactivation effect on the cobalt catalyst was different in each reaction. For instance, the deactivation effect on the rate constant of the oxidation of MTA was about three times as effective as that of DBA. The retardation effect of MOA per molecule is almost the same as that of TMA. The oxidation of PC is also retarded by the presence of TMA and MOA; however, there is no relationship between decrease in the rate constant and TMA and MOA concentrations (Fig. 1). In the continuous oxidation of PC, k₂, the rate constant of the DBA→MPA step, is almost proportional to ([Co]-[TMA]) (Fig. 8).
The formation of insoluble compounds containing TMA, MOA and Co by heat treatment of the filtrate of the reaction mixture was observed. These insoluble compounds were thought to be of two kinds and the mole ratios of (TMA+MOA) to Co of the two kinds of compounds are close to 1 (Table 1). The rate of formation of these insoluble compounds was accelerated by the addition of a model precipitate as a nucleus of crystal and the amount of the precipitate approached maximum after treating at 140°C for 1hr. (Fig. 10). The amount of precipitate was proportional to the concentrations of Co and TMA, and the value of ([Co]× [TMA]) of the filtrate could be reduced to 0.05-0.08 (wt%)² by this treatment (Figs. 11, 12).
Using a circulating system, including the steps for heat treatment of the filtrate of the reaction mixture and for separation of the precipitate formed, PC was continuously oxidized for a long time during which MPA was produced without a marked decrease in the rate constant of each step (Table 2, Figs. 15, 16).

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A formula was proposed to estimate the atmospheric flow activation volumes of synthetic ester lubricants from their molecular structures based on the assumption of independent movement and contribution of each flow unit of the ester molecule. The estimated activation volumes were in good agreement with those of the experimental. Data, reported by other investigators for high pressure viscosities of several hydrocarbons, were used to test the applicability of the proposed formula. Limitations in its applicability were also discussed.

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This report deals with a fully automatic computeroperated reaction system (FACORS) which was designed and developed for a wide variety of automatic experiments, with or without on-line analysis and feedback of data, in research on catalytic or on non-catalytic reactions carried on in a laboratory-scale continuous flow reaction apparatus.
Fig. 1 shows a schematic diagram of FACORS designed to automate the following seven processes which are very common in various experiments in the laboratory:
(1) controlling variables such as reactor, catalystbed temperatures; flow rates, compositions, and pressures of fluids; process times; the paths of flowing substances; etc., (2) sampling products and operations for analysis by such means as gas chromatograph and mass spectrometer, etc., (3) measuring and recording process variables, (4) logging analytical data, (5) summarizing data obtained and preparing tables and graphs, (6) performing analysis and comparison of the data, and (7) deciding whether or not to continue, change, or stop the experiments based on the feedback of the results from (6) and others, and deciding the experimental conditions for subsequent experiments.
The automation of these (1)-(7) processes by use of a single computer (see the legend of Fig. 1) made it possible to perform a variety of fully automatic, unattended feedback and/or feedforward experiments; such as activity and life tests of catalysts, determination of optimum reaction conditions, repetitive operations such as reaction/regeneration or adsorption/desorption cycles, various temperature programmed experiments for examination of the properties of catalysts.
Two examples of unattended feedback experiments, Ex-(A) and Ex-(B), were carried out by use of FACORS to reveal the advantages and characteristics of the system. The Ex-(A) is for the determination of optimum reaction conditions [reaction temperature(T) and flow rate of reactant(F)] to attain the maximum yield of ethylene in Eq. (1). The flow diagram for Ex-(A) is illustrated in Fig. 3 and the results are shown in Figs. 5 and 6, which were drawn by a GP (Fig. 1), and summarized in Table 1. The profiles of T and F (uncorrected values) recorded on a RC (Fig. 1) during the course of Ex-(A) are shown in Fig. 4.
The Ex-(B), which consists of alternate reaction/regeneration cycles of Eqs. (2) and (3), was carried out according to the flow diagram illustrated in Fig. 7. Variation in the concentration of methane produced (y(t)) and time-averaged yield (Y(t)) obtained by online integration of y(t) using Eq. (4) during the course of reaction are shown in Figs. 8 and 9, respectively. At about 5hr after the start of the optimization experiment (see Fig. 7) the computer found the optimum time of reaction ((t)_opt=27±2min) and that of regeneration ((t_o)_opt=12.5±0.2min) with the maximum timeaveraged yield ([Y(t)_m]_M=1.15+0.05μmol•min^-1).
In conclusion, the major advantages of the system developed here are as follows: (i) A wide variety of "unattended" feedback and feedforward experiments are possible. (ii) Experiments with previously unknown objective conditions could be carried out. (iii) Once the programs are designed, even a nonprofessional can readily perform complicated experiments. (iv) The present system gives us well-organized original data as well as analysed ones, which are recorded on a tape or a disk of a computer. They are convenient for storing, carrying, reproducing, re-analyzing, and transforming into tables and graphs. (v) The data obtained are of high accuracy, reliability, reproducibility, and objectivity.

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In order to elucidate the stereochemistry of 1:2 adducts derived from the Diels-Alder reactions of cyclopentadiene and isoprene, 1:1 adducts were allowed to react with additional cyclopentadiene or isoprene. Several trimers having a norbornane or a norbornene skeleton were the predominant products, comprising more than 80% of the trimers yielded. Although a few isoprene dimers were obtained, no 1:2 adduct involving isoprene dimer was produced. The configuration of 1:2 adducts 8 through 15, except for 10 and 11, was established by means of ¹³C-NMR spectroscopy.

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Two kinds of oil shales were retorted mostly under hydrogen pressure to clarify the effects of pressure, inlet gas flow rate, kind of gas and type of retort used. Although the yield of oil per weight of shale was not improved, lighter shale oils were obtained under higher pressures. Based on the hydrogen balance, a considerable amount of hydrogen was consumed in retorting, and the amount increased with increase in pressure. The rate of gas flow had a slight effect on the properties of the oil. Moreover, the type of retort, i.e., a box-type and a shaft-type retort, affected the properties but slightly, too.

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The adsorption of alkaline-earth metal salts of dinonyl-naphthalene sulfonic acid(DNNS) on carbon black was studied in a three-component system consisting of Solvent I (n-heptane), Solvent II (polar compounds and others), and DNNS in which the influence of Solvent II was investigated. The adsorption of DNNS is influenced by the kind of Solvent II used. The amount of adsorbed DNNS on carbon black decreases sharply with increasing amount of polar solvent, particularly, in the range of low fractions of the solvent. Non-polar solvents exert mild degrees of influence. Similar phenomenon was observed in the actual diesel engine sludge. There is a trend in the influence on adsorption of BaDNNS by polarity and by solubility parameters of the solvent II used. An isotherm equation for competitive adsorption was derived from the equilibrium theory and found that it was applicable to the data obtained in the present three-component system. Dispersancy of carbon black particle correlates with the amount of adsorbed BaDNNS at low concentrations of 1-propanol.

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The test methods to evaluate scoring resistances of automotive gear oils, were studied by means of the vehicle test using a 1, 770cc passenger car and the laboratory test using a Timken extreme pressure test machine.
(1) The vehicle tests were carried out on a chassis dynamometer under a driving mode of the modified IP-MIRA high speed shock test. Under the first test condition (Method A) which corresponded to the acutual even-road driving, scoring did not occur even with the SAE 80 GL-3 gear oil (Table 6). Therefore, the next test condition (Method B) was set in order to increase the strengths of shock loads. The running resistance of method B was based only on inertia resistance; and other resistances, for example, rolling resistance, air resistance, speed resistance and grade resistance were neglected. Under this condition, scoring was found on the coast side surface of the ring gears and on the pinion gears in the case of GL-3 and GL-4 gear oils. The scored area seem to be proportional to the scoring resistance of each oil (Table 7). These results indicate that the vehicle test by method B is suitable as a scoring test method for evaluation of scoring-resistances of various grade gear oils.
(2) In order to establish a laboratory screening test method that correlates with the vehicle test, scoring resistances of automotive gear oils were examined using the Timken test machine under various test conditions.
The test conditions used are shown in Table 4.
The results are shown in Table 8. It was found that the results obtained under the standerd test condition "800rpm•52°C", which is defined by the Fedcral Test Method, did not correlate with the results of the vehicle test. On the other hand, the results under test condition "2, 000rpm•95°C" correlated with the vehicle test results (Fig. 7). These results would suggest that the test condition "2, 000rpm•95°C" is much closer to the lubricating condition of the vehicle test. We call this Timken test condition "high speed-high temperature test method".

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Further investigations on high temperature methanation catalysts are not only desirable but also necessary. With such catalysts, the overall heat efficiency of current coal gasification-SNG processes could be improved. Moreover, these catalysts can also be used in a chemical heat pipe system, which is one of the efficient energy transfer systems.
The thermal stability of Ni-Mo alloy catalysts supported on zirconia for high temperature methanation was tested at 650°C, 80kg/cm² and 15, 000hr^-1 GHSV for several weeks using a feed mixture containing 15% of carbon monoxide, 45% of hydrogen and 40% of methane. Shown in Table 2 are four kinds of zirconium compounds, monoclinic zirconia, zirconyl hydroxide, zirconyl carbonate and stabilized, cubic zirconia, used as support materials. The results of the thermal stability tests are shown in Figs. 1-4, in which the methane concentration at temperatures lower than the thermal stability test temperature, 650°C, is represented as a measure of the catalytic activity at that temperature. As a result, Ni-Mo-ZrO₂-1 maintained its high activity in the temperature range of from 400 to 500°C for 4 weeks in spite of the rapid decrease in its initial activity. On the other hand, the activity of Ni-Mo-ZrO₂-2 and that of Ni-Mo-ZrO₂-4 were low initially but they increased with progress of the test, but their catalytic activities were lower than the activity of Ni-Mo-ZrO₂-1 even at the end of the test. For Ni-Mo-ZrO₂-3, its catalytic activity was low throughout the test. Thus, Ni-Mo-ZrO₂-1 supported on monoclinic zirconia was found most active among the catalysts tested.
The result of X-ray diffraction analyses on these catalysts are shown in Figs. 5-8 and Table 2. The diffraction peaks identifiable with Ni-Mo alloy and metallic molybdenum were observed for all of the catalysts tested after hydrogen reduction at 700°C. The Mo content in the Ni-Mo alloy decreased with progress of the test, as shown in Fig. 10. Metallic Mo disappeared and Mo₂C appeared at the same time.
The crystal forms of zirconia in Ni-Mo-ZrO₂-1 and Ni-Mo-ZrO₂-4 did not change during the test. On the other hand, the amorphous zirconia in Ni-Mo-ZrO₂-2 and Ni-Mo-ZrO₂-3 before hydrogen reduction, appeared as tetragonal and monoclinic zirconia after reduction.
As to the carbon content of the catalysts, no increase was observed except the rapid increase on the first day of the test for all catalysts as shown in Fig. 9. If all of the Mo atoms in the catalysts had been changed to a mixture of Mo₂C and Ni-Mo alloy containing 10 atomic % of Mo, the calculated carbon content of the catalysts tested would be 1.0% by weight; thus, the observed value of 1-2% would not be considered large.
According to the results above, monoclinic zirconia is considered to be the best support material for the high temperature methanation catalysts investigated. The reason may be attributed to the less extent of interaction between the monoclinic zirconia possessing covalent nature and the nickel and molybdenum oxides in the calcined catalyst. On the other hand, for other three catalysts, a greater extent of interaction between zirconium compounds and the nickel and molybdenum oxides is expected from the results described below. One of the results is the increase in activity in the early stages of the test. This may indicate that incompletely reduced oxides by hydrogen treatment might be rereduced during the thermal stability test. The other is that the catalysts were amorphous before they were subjected to the hydrogen treatment.

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Organic and inorganic pollutants in oil shales, spent shales, retort waters and shale oils produced by retorting of oil shales from Thailand and Colorado were analyzed to study the trend in the distribution and contents of the pollutants in these products. As a result, 65wt% of Pb and 95wt% of As were found in the spent shale, and the oil contained a maximum of 15ppm of As. The content of As in the oil decreased with increase in the pressure of hydrogen during retorting of the oil shale. Pb, Mn, Cr and V, which are potentially poisonous to oil refining catalysts, were not detected in both shale oils, and the contents of other metals were less than 10ppm.

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The dynamic structure of calcium dodecylsalicylates, which are employed as principal detergent-dispersant additives in engine oils, in micellar states in chloroform was studied by measurements of ¹³C-NMR spectra and spin-lattice relaxation times with the following results. The resonances from the aromatic ring and the five carbons of the dodecyl group nearest the aromatic ring, which constitute the inner part of the reversed micelle of salicylates, were broadened as compared to those of dodecylsalicylic acid. This showed that the local mobility of the inner part of the reversed micelles was considerably restricted as in the solid state, whereas the local mobility of the remaining carbons of the dodecyl group were not affected. The relaxation study showed that the segmental mobility of the alkyl chains gradually became greater as the distance separating the carbons from the aromatic ring increased. The effects of the addition of water on the structure of the micelles were also studied. The addition of water decreased slightly the broadening of the resonances from the inner part of the reversed micelles. This is probably due to hydration or formation of aqueous solutions in the micellar core, resulting in an increase in the local mobility.

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The yellow dark green anthracene species chemisorbed on SiO₂-Al₂O₃, activated at 550°C under 10^-4 Torr for 3hr, exhibited, in the range from 1, 600 to 1, 450cm^-1, several absorption bands which were very similar to the ring stretching bands of the anion radical or of the 9-anthracenium ion, but there were no bands arising from the aliphatic groups. These observations indicated that most of the species were for the first the σ-complex produced between the adsorbate and a Lewis acid center, and for the second the cation radical.

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