The chemical compositions of benzene soluble fractions of eleven petroleum residues were investigated by means of flame ionization detector-thin layer chromatography (TLC-FID), and the results were analyzed using triangle diagrams involving various amounts of sulfur and analytical values of chemical composition. As a result, we were able to separate from petroleum residues into three different groups of optical texture.
The change in the chemical compositions of benzene soluble fraction samples 1, 5, and 6 during early stages of carbonization was also determined by TLC-FID. From the results obtained, it was found that a large difference existed between vacuum residues (samples 5, 6) and sample 1 in the change of chemical composition resulted by the carbonization reaction.
The maximum amount of asphaltene was 40% for vacuum residues, while that for sample 1 was only 10 % during carbonization.
We also examined the effect of rate of heating on the optical texture of the cokes. With increasing rate of heating the resultant cokes showed decrease in the size of the anisotropic unit of mesophase.

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Oxidation of 1-butene to methyl ethyl ketone (MEK) was carried out with a palladium chloride-cupric chloride-aqueous-solution catalyst at elevated temperatures and pressures in order to obtain the basic data for manufacturing MEK by Wacker process. The metallic palladium formed by carbonyl oxidation (carbonyl formation) was reoxidized simultaneously with cupric chloride to generate palladium chloride which was repeatedly utilized as oxidation catalyst. The selectivity to MEK was reduced above 130°C, suggesting the occurrence of side reactions. 3-Chloro-2-butanone was the main byproduct in the Wacker process for manufacturing MEK, and this was the result of further reaction of MEK with cupric chloride. The addition of hydrochloric acid to the catalyst solution caused a decrease in the oxidation reaction rate, which was similar to the result of butene oxidation at room temperature and atmospheric pressure.

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Diels-Alder reaction of cyclopentadiene and butadiene gives several dimers, which are considered to be valuable materials for various organic preparations. The cis-dihydroxylation of these dimers with N-methylmorpholine-N-oxide in the presence of a catalytic amount of osmium tetroxide was investigated to examine the regio- and stereoselectivities of the reaction. The hydroxylation of 4-vinyl-1-cyclohexene occurred exclusively at the double bond of cyclohexene ring to give two stereoisomeric mixture of cis-diols 2a and 2b. 5-Vinyl-2-norbornene led to the cis-diol 4 which was hydroxylated regio- and stereoselectively. The same reaction of cis-3a, 4, 7, 7a-tetrahydroindene gave cis-diols, 6 and 7, and tetrol 8 with a high stereoselectivity. On the other hand, the cis-hydroxylation of endo-dicyclopentadiene gave diols, 10 and 11, but that of exo-isomer afforded only cis-diol 13. Cis-dihydroxylation of norbornene ring and that of cyclopentene ring proceeded stereoselectively by one side attack, but that of cyclohexene ring occurred at both side of double bonds. It was assumed that these selectivities depended on the reactivity of double bond and on the steric effect between the substrate and oxidizing reagent in the transition state.

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The effects on the cracking reaction of vacuum gas oil of nickel and vanadium impregnated on FCC catalysts were examined. The reaction was carried out using a fixed bed flow reactor in the same manner as described in ASTM D-32.04 (ASTM Micro Activity Test). The catalysts were impregnated with nickel and vanadium naphthenates and steam deactivated before the microactivity tests were made. The metal tolerance of REY zeolite was also examined by measuring its crystallinity retention.
The catalytic activity for conversion and that for gasoline yields were fairly constant up to about 10, 000ppm of nickel as shown in Fig. 1. On the other hand, the impregnated vanadium poisoned the active sites of the FCC catalyst decreasing the degree of conversion and of gasoline yields. The catalytic activity of nickel for coke and hydrogen production was greater than that of vanadium (Fig. 2). As shown in Fig. 3, the decrease in the activity due to vanadium impregnation was brought about largely by the temperature of steam deactivation, i, e., the difference in the activity loss of the metal-free and vanadium-impregnated catalysts that increased with increasing temperature from 730°C to 770°C. The dehydrogenation activity of nickel and vanadium was not additive.
The crystallinity retention of metal-free and that of metal-impregnated zeolites were measured after calcination or after steam aging at 750°C (Fig. 4). The crystallinity of vanadium-impregnated zeolite decreased largely after steaming in agreement with the results of Figs. 1 and 3. Moreover, the exchangeable sodium ions found in the zeolite substantially accelerated the structural degradation of the vanadium-impregnated REY (Table 2). After calcined at 750°C in air, the degree of structural degradation of the vanadiumimpregnated REY was almost the same as that of the metal-free REY. These results suggested that the collapse of zeolite structure was probably due to the interaction of vanadium oxide with the lattice oxygen of zeolite.

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The catalytic activity of the Si-Ce type oxides containing the Va group-elements for vapor-phase oxidative dehydrogenation of ethylbenzene has been studied. The Mo-Ce-X (X: the Va group-elements, P, As, Bi or Sb) type oxides have also been used in order to compare their activities with those of the Si-Ce-X type oxides.
The reaction was performed at 480°C and at GHSV 1, 300-6, 500hr^-1 using a gaseous reactant mixture with the ethylbenzene/oxygen molar ratio of 1 or 1/2.
When SiO₂ and Si-Ce (1:1) binary oxide were used as the catalyst, the yield of styrene was 6.5% and 12.5 and its selectivity was 39.4% and 37.2%, respectively (Table 3). By the addition of a small amount of Sb component to the Si-Ce (1:1) binary oxide, the selectivity of styrene increased remarkably though the activity decreased. By increasing the amount of Sb component in the catalyst, the activity increased (Fig. 3). The largest yield of styrene, 44.0% with selectivity of 87.0%, was obtained by using the Si-Ce-Sb (1:1:1) oxide catalyst. In this case, the major products, excluding water, were styrene and carbon oxides, and the amounts of other products including benzaldehyde were very small (Table 4).
The Mo-Ce-X type oxide showed a high activity for n-butene oxidative dehydrogenation which is known to proceed via π-allyl intermediate (Table 1). When this catalyst was used in the oxidation of ethylbenzene, substantial amounts of benzaldehyde, benzoic acid, and benzene were formed and the yields and selectivitys of styrene were very low (Table 2).
The conversion of ethylbenzene and the yields of styrene over the Si-Ce-Sb (1:1:1) oxide catalyst increased during the reaction for 10-20 hours, and the selectivity of styrene showed a constant and high value throughout the reaction period (Fig. 4).
Acidity increased with increasing amount of Sb component (x) in the Si-Ce-Sb (1:1:x) oxide catalyst (Fig. 6). The formation of coke was observed on the Si-Ce-Sb (1:1:1) oxide catalyst during the reaction. The IR spectroscopy and elementary analysis of used catalyst suggested that the coke consisted mainly of a polynaphthoquinone-type compound which was considered to be active for the oxidative dehydrogenation of ethylbenzene to styrene.

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Hydrodenitrogenation of Taching atmospheric residue was performed in a fixed bed co-current up-flow reactor packed with a Ni-Mo/Al₂O₃ catalyst under 50-200kg/cm² and 360-440°C, and the characteristics of the residue hydrodenitrogenation and effects of sulfur on the reaction were investigated. Nitrogen was found to be considerably poorer than sulfur in reactivity with hydrogen. One of the reasons could be that nitrogen's existence was more localized than sulfur in the heavier fractions. Hydrodenitrogenation of Taching residue was promoted markedly by adding a sulfur compound to the feedstock. This sulfur is assumed to be hydrogenated to hydrogen sulfide that activated the catalyst by keeping it in the sulfided state, and 2% of sulfur in the feedstock seemed adequate. Hydrodenitrogenation was found to be closely related to hydrocracking. The nitrogen removal was linearly correlated with the hydrocracking ratio represented by the decrease in the molecular weight within the range of nitrogen removal above 30%.

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The behavior of complexes of iodine and asphaltenes derived from Khafji and Minas crude oils (KF-VO and SL-VO) was investigated by using the ESR technique. Two kinds of radicals are present in the asphaltenes. One corresponds to a paramagnetic species obeying the Curie-Weiss law (Eq.(1)). The other is a sort of complex with charge-transfer nature, i. e., the ESR signal intensity of which shows temperature dependence expressed as Eq. (2). The free radicals can be distinguished by analyzing the temperature dependence of the signal intensity.
The ratios of the numbers of the radicals obeying the Curie-Weiss law (N_d) to the total number of the radicals (N_d+N_st, where N_st is the number of the charge-transfer complex radicals), were evaluated in terms of the relative intensity curves for the asphaltenes containing various amounts of iodine (Fig. 2). In addition, the values of N_d and N_st were determined by measuring the radical concentrations (Fig. 3), and they were plotted against the amounts of iodine in Fig. 4.
The results obtained from the variations of N_d and N_st with the addition of iodine suggest that, with addition of less than 10wt% of iodine, its molecules sandwitched in the asphaltene micelles dissociate the complex radicals present originally between the asphaltene layers and produce charge-transfer complexes with the polycondensed aromatic molecules unrestricted in the asphaltenes. Further introduction of iodine is considered to result in an increase in the iodine-asphaltene complex, which delocalizes positive holes and electrons in the complex.
From the behavior of the system of iodine-asphaltene pretreated at 430°C, it is concluded that incorporation of iodine molecules into the KF asphaltene is hindered by the rigid structure of the micelles, whereas the molecules can readily be included between the aromatic layers in the SL asphaltene because of the increase in the mobility of asphaltene components with heat-treatment.

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A bench-scale investigation of hydrocracking o Canadian Cold Lake bitumen was performed using a discharged hydrodesulfurization catalyst to produce distillable hydrocarbon fractions.
The cobalt molybdate catalyst, withdrawn from a commercial residue HDS unit, contained 12.9wt% carbon, 9.6wt% vanadium and 2.1wt% nickel as the deposits. The catalyst was crushed to 45-325 mesh and slurried with bitumen (whose properties are given in Table 1) to obtain an oil-to-catalyst ratio of 100/3.37. Hydrocracking was carried out in two 5-l reactors in series at a constant hydrogen pressure of 100kg/cm², temperatures of 430, 440 and 450°C, and liquid hourly space velocities (LHSV) of 0.27-1.25 volume of oil per volume of the reactors per hour.
The operating conditions and results of the nine runs are summarized in Table 2. The conversion of 500° C+ material to lighter distillates shown in the last column of the table ranged from 47% to 88%. Temperature and LHSV greatly affected the conversion, which increased with decreasing LHSV or/and with increasing temperature. As the conversion increased, specific gravity, viscosity, Gonradson carbon residue, average molecular weight, and nitrogen and metals contents of the product oil decreased, whereas hydrogen consumption, yields of gaseous hydrocarbons, C₅-340°C fraction and carbonaceous substances increased. However, to attain the same level of sulfur removal, a higher conversion level was required at higher temperature than at lower temperature as indicated in Fig. 3.
Assuming that the cracking rate is of the first order, and applying the rate equation of the continuous feedstirred tank reactors, Eq.(1)*, 500°C+conversion data obtained at 430, 440 and 450°C are plotted in Fig. 1. The rate constants were calculated from the straight lines for the three temperatures. The temperatures and rate constants in the Arrehenius equation are plotted in Fig. 2 and an activation energy of 55 kcals was obtained from the slope of the plot for 500°C+ conversion. Simlilarly an activation energy of 53 kcals was obtained fbr 340°C+ conversion as shown in Fig. 2.
The product oil was fractionated into seven fractions using a packed column still. Table 3 shows the yields of the fractions. The yields of naphtha fractions were relatively low and the yields of kerosene and gas oil fractions were high that would be the characteristics of this slurry reaction process as in the case of hydrocracking of petroleum atmospheric and vacuum residuess3), 5). The properties of the fractions are listed in Tables 4-9. The nine runs are arranged in the tables in the order of increasing conversion. It was observed in some fractions that the content of aromatics increased and that of olefins or naphthenes decreased with an increase in the conversion. The fractions did not meet all of the petroleum fuel specifications, and each fraction, which colored rapidly in air, contained a considerable amount of olefins.
These results indicate that discharged HDS catalysts can be used in the slurry process to hydrocrack oil sand bitumen to give distillates in good yields. The distillates would, however, require upgrading to produce marketable fuels.
* The nomenclature in Eq. (1) is as follows:
k: rate constant, hr^-1
V: volume of a reaetar, l
F: feed. rate, l/hr
C₀: concentration of residuum in feedstock, wt/wt
C: concentration of residuumin product oil, wt/wt

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Zinc dialkyldithiophosphate (ZnDTP) is used widely in motor oils, diesel engine oils and industrial lubricating oils because of its excellent extreme pressure and anti-oxidation properties. These properties depend mainly on the structure of the alkyl group in the Zn-DTP molecule.
The characterization and determination of alkyl groups of fourteen ZnDTPs were successfully conducted by using ¹³C-NMR (Table 1) with the aid of mass and infrared spectroscopies.
In ¹³C-NMR spectra the chemical shifts of α-carbons and β-carbons of the alkyl groups appear in the range of 65-75ppm and 20-50ppm, respectively (Tables 2, 4 and Figs. 1, 3, 4), and their signals are doublets owing to the coupling with ³¹P nucleus (Tables 2, 4).
The analyses of ¹³C-NMR spectra of ZnDTPs were performed with the aid of these facts and the Lindeman-Adams' rule, and the distribution of different alkyl groups was determined from the integrated areas of the α-carbons.
The analytical test results of alkyl groups of the fourteen ZnDTPs are shown in Table 3, which indicates that main alkyl groups of commercial ZnDTPs are branched and of low molecular weights, such as isopropyl, isobutyl, sec-butyl, 4-methyl-2-pentyl and 2-ethylhexyl. It also indicates that four ZnDTPs out of the fourteen are single-component types and their alkyl groups are 4-methyl-2-pentyl and 2-ethylhexyl, whereas the others are mixed-ester types.
The alkyl groups of ZnDTP contained in commercial lubricating oils and in additive concentrates can be identified and characterized by ¹³C-NMR spectroscopy provided that they are properly processed before analysis.

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The pitch gasification process produces reducing gas (H₂+CO) for iron ore reduction from petroleum pitch by utilizing the heat generated in a high temperature gas-cooled reactor. The process comprises mixing anthracene oil with a petroleum pitch of low hydrogen content and high softening point; blowing the mixture into a gas-solid fluidized bed (coker) composed of inorganic particles fluidized with high temperature steam to produce cracked gas and oil; and finally, gasifying the resulted coke with high temperature steam or steam-oxygen in a gas-solid fluidized bed (gasifier).
A pilot plant capable of feeding pitch at the rate of 4.8 tons a day was built in 1978, and it had operated for a total of 3, 000 hours, including 800 hours of continuous gasification. The physical properties of the petroleum pitch used in the pilot plant are shown in Table 4, and the process flow in Fig. 2. The design data for the principal apparatus are shown below and in Table 1, and the operation data are shown in Table 3:
Temperature (°C) Pressure (kg/cm₂ G)
Coker 650 3
Gasifier 950 3
_{Fig. 3} shows the results obtained from the coker in the pilot plant. The yield of gas (C₄^-) was 14%, and the yield of coke was 38% at 650°C and 3kg/cm² G. Table 5 shows the composition of the gas. The coke yield in a single pass corresponded to 78% of fixed carbon in the petroleum pitch.
Fig. 5 shows that variation in the rate of coke gasification in the coker is related to the difference in the content of sodium in the petroleum pitch.
Table 6 shows the composition of the gas generated from the gasifier in the pilot plant. The concentration of methane in the gas was from 0.7 to 2.5mol% based on dry gas before the removal of the acid gas, which is shown in Fig. 9, and it is from 1.5 to 4 after the removal. Nitrogen in the coke was found in the form of ammonia, and the sulfur in the form of hydrogen sulfide.
Fig. 8 shows the deviation from the equilibrium of the CO shift reaction of the gas produced in the gasifier, and it indicated an equilibrium temperature calculated from the composition of the gas, which was higher than the reaction temperature.
Table 7 shows a loss of heat in the pilot plant, and it indicated that 14% of the heat input was lost.
The following three processes for producing reducing gas from petroleum pitch by utilizing nuclear energy were tried, and their thermal efficiencies were examined under the conditions shown in Table 8:
Case 1: Gasifying process employing steam at 2, 000 °C as shown in Fig. 10
Case 2: Gasifying process in which coke is burned with air as shown in Fig. 11
Case 3: Partial oxidation process as shown in Fig. 12.
Case 1 showed the highest efficiency, and case 2 was also found promising.
By utilizing nuclear energy, cases 1 and 2 make it possible to save 19% and 28% of fossil energy, respectively, in the production of reducing gas.

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A simulator for unsteady state gas flow in pipe lines was made in the computer. The gas flow was indicated by the Kinetic Formula and the Continuity Equation. The Simultaneous Difference Equations of these equations were used in the simulator, and the simulations were conducted to find the best simulation approach. The final simulation selected matched the field performance satisfactorily.

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The heat consumption of distillation column is considered for both the open steam and reboiler systems. The Ponchon-Savarit method is used for calculations.
Cases (A), (B) in Fig. 1 show the calculated results of the bottoms product composition and the theoretical number of plates when feed composition, distillate composition, reflux ratio, heat consumption, and the total number of plates are the same. Cases (A), (C) in Fig. 1 show the calculated results of heat consumption when feed composition, distillate composition, reflux ratio, bottoms product composition, and the total number of plates are the same. The enthalpy-composition diagram used is shown in Fig. 2. The calculated results are summarized in Table 1.
Comparing the results of cases (A), (B) in Fig. 1. it is found that the open steam method requires much more theoretical number of plates, but the ethanol content in the bottoms product becomes smaller. Comparing the results of cases (A), (C) in Fig. 1, it is found also that less heat is required by heating with open steam than with a reboiler. This heat saving effect becomes greater as the ethanol content in the bottoms product becomes larger.

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Niobium sulfide, Nb_1.158S₂, was synthesized by niobium pentoxide reacting with hydrogen sulfide at 700°C. Its lubricating properties were compared with those of molybdenum disulfide using a pendulum type friction tester and the Falex machine when they were added to the lithium soap/liquid paraffin grease. Niobium sulfide gave a lower friction coefficient and better extreme pressure properties than MoS₂.

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