As one aspect of the studies concerning desulphurization of flue gases by active carbon, the desorption of sulphur dioxide from active carbon was investigated. The adsorption of sulphur dioxide into the active carbon from flue gases at 100∼150°C is an adsorption involving chemical reactions, and the sulphur dioxide changes into sulphuric acid on the active carbon. The desorption rate of sulphur dioxide by thermal desorption is affected greatly by the temperature. The desorption reaction begins gradually at 200°C and the rate increases rapidly at 300°C. Sulphur dioxide and carbon dioxide are formed during the desorption and adsorbed water is eliminated at the same time. The molar ratio of the carbon dioxide to the sulphur dioxide is fixed by the temperature of desorption regardless of the quantity of sulphur dioxide adsorbed, and it is less than 0.5 when the temperature is under 750°C. The desorption reaction with superheated steam is a 1.5-order reaction, and the energy of activation is 7.98kcal/mol.

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In the present work such factors, which influence the reaction rate in residue hydrodesulfurization, as space velocity, temperature, pressure, hydrogen gas rate and feed oils were studied. In addition, trial catalysts were compared with a commercial catalyst for hydrogen consumption and catalyst activity. From the experimental results the following conclusions were obtained.
(1) The rate of desulfurization reaction was apparently second order with respect to the sulfur concentration. The apparent activation energy was about 25kcal/mol.
(2) The rate of sulfur removal increased linearly with increasing reaction pressure in the range of 50∼140kg/cm².
(3) The effect of hydrogen gas rate on the rate was relatively small in the range of 500∼1, 000Nl/l.
(4) Khafji atmospheric residue was more difficult to desulfurize than Kuwait residue.
(5) The trial catalysts were superior to the commercial catalyst with respect to hydrodesulfurization activity and hydrogen consumption.

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A new method is developed for calculations of the multicomponent distillation in complex column having any number of feeds and multi-side streams. This method employs the group relaxation algorithm for the solution of the non-linear material balance equations at unsteady state condition around each stage in the column. The non-linear material balance equations are solved simultaneously for each component, therefore, no matching is required.
The method may will be applied to either ideal system or nonideal system multicomponent distillation to calculate the product distribution and the composition and temperature profiles in the complex column, when one specifies the column pressure, the number of plates, the rate, composition and thermal condition of each feed as well as the locations of the feeds plate and the side-streams.
The method may be started with the assumption only that all the liquid compositions on each stage equal to the overall-feed compositions.
Therefore, a great deal of experience and judgment in choosing initial values are unnecessary. And also both distributed and non-distributed components are handled with equal case.
The computational procedure is simple, and numerically stable. Some problems were discussed to demonstrate the feasibility of the method.

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This paper considers surface temperatures in extreme pressure lubrication. The EP failure temperatures are estimated utilizing Shell-4 Ball machine for five sulfur and two chlorine compounds. It is shown that EP film failure can be considered to occur at a constant critical temperature. Also the estimated surface temperatures are utilized to develop a different model for EP lubrication failure. Analysis of the temperature problem indicated that EP films are not insulating and evidence to this effect under dynamic conditions is presented utilizing electrical contact potential measurements. Finally a brief consideration is given to the possible elasto-hydrodynamic effects under certain conditions.

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The initial rates of the catalytic disproportionation of propylene were determined under controlled conditions in a closed circulating glass reactor. The catalysts used were MoO₃-Al₂O₃, WO₃-Al₂O₃, and WO₃-SiO₂, being typical combinations of promoters and supports. The initial rate data obtained are discussed and are correlated by a rate expression based upon a dual site Langmuir-Hinshelwood mechanism; the same expression is also derived from a mechanism involving a four center intermediate and a Langmuir type adsorption. The data obtained for the MoO₃-Al₂O₃ catalyst or the WO₃-Al₂O₃ catalyst are well correlated by this expression. It is considered that the adsorption of propylene on WO₃-SiO₂ catalyst obeys the Freundlich equation rather than the Langmuir isotherm. In the range of low pressure, however, the data obtained on the WO₃-SiO₂ are also correlated by the above mechanism. The activation energies for the surface reaction are evaluated to be 5.15kcal/mol on the MoO₃-Al₂O₃, 14.8kcal/mol on the WO₃-Al₂O₃, and 11.5kcal/mol on the WO₃-SiO₂.

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The hydration of ethylene over various solid acids such as metal sulfates, phosphates, oxides, solid phosphoric acid and cation exchanged zeolites was investigated in a closed circulation system at 160∼300°C.
Ferric and aluminum sulfates and zeolites Y showed high catalytic activity in comparison with solid phosphoric acid, SiO₂-Al₂O₃, zeolites A and all other catalysts. The selectivity for ethanol formation was extremely high in metal sulfates and zeolites A, but low in SiO₂-Al₂O₃ and zeolites Y. The order of activities of metal sulfates was Fe₂(SO₄)₃>Al₂(SO₄)₃>NiSO₄>Cr₂(SO₄)₃>CuSO₄>MnSO₄>CaSO₄. The catalysts those acid strength in their dried state was as strong as -8.2<H_o_??_-3 were found to be active and selective for ethanol formation. The activities of cation exchanged zeolites A which varied in order of Mg-A>Cd-A>Zn-A>Ca-A>Ag-A>Sr-A>La-A∼Ce-A were shown to correlate with the electronegativities of exchanged cations and the adsorption heats of ethylene.
The rate of ethanol formation increased as the mole ratio of H₂O/C₂H₄ decreased. The experiment on the reaction of ethylene with heavy water showed that deuterium did not transfer into ethylene at all. It was concluded by analyzing the kinetic data that the formation of an adsorbed ethyl carbonium ion from an adsorbed ethylene and a proton on acid sites was the rate-determining step of the hydration.

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Benzene-steam and alkylbenzenes-steam reactions over a silica-supported nickel catalyst have been studied under atmospheric pressure in a temperature range of 370∼430°C.
In the reaction of benzene-steam, the methane yield is lower and the carbon dioxide yield is higher than the estimated value. The reaction is zero order with respect to benzene and approximately first order with respect to steam.
In the reaction of alkylbenzenes-steam, ring breakdown and dealkylation occur at the initial stage of reaction, and the former occurs more easily than the latter at high conversion and at high temperature. The number and the position of the alkyl group on the benzene ring influence the reaction rate and the selectivity.
The reaction path of dealkylation is proposed as follows:

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The condensation of C₉ aromatic hydrocarbons (C₉) with CH₃CHO in the presence of H₂SO₄ and the catalytic cracking of the condensation products over a SiO₂-Al₂O₃ catalyst were investigated. The isomer distribution of 1, 1-diarylethanes (DAE), the condensates formed, were measured. DAE formed from n- and i-PB (Abbreviation of each C₉ isomer is noted in Table 1), and 1, 3, 5- and 1, 2, 4-TMB consisted of a single isomer, while three DAE isomers were formed from o-, m-, and p-ET, 1, 2, 3-TMB, and indane, respectively. The reactivity of C₉ in the condensation was expressed in the increasing order as follows: 1, 2, 4-TMB>1, 2, 3-TMB>m-ET>indane>1, 3, 5-TMB>o-ET>p-ET>i-PB>n-PB.
When C₉ reformate was used as an aromatic feed, the concentrations of n-PB and ET in unchanged C₉ increased 1.5 times after the condensation reaction, and the concentration of 1, 2, 4-TMB in C₉ obtained by the catalytic cracking of DAE increased 2 times.
About 80% of 2, 4, 5-TMPE (1, 1-bis (2, 4, 5-trimethylphenyl) ethane) formed from 1, 2, 4-TMB was obtained by chilling the crude condensation products. About 90% of alkylstyrenes obtained by the catalytic cracking of the condensate were composed of o-substituted isomers.

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The autoxidations of aromatic hydrocarbons are inhibited by the addition of boric acids and their derivatives, whereas the oxidations of aliphatic and alicyclic hydrocarbons are not inhibited and give selectively a boric ester of the corresponding secondary alcohol. In order to clarify these facts, tetralyl and cumyl hydroperoxides were decomposed by several types of boric acids and their derivatives. The rates of decompositions of these hydroperoxides were significantly accelerated by the boric acids and their derivatives, and γ-o-hydroxyphenylbutylaldehyde and phenol were produced selectively from tetralyl and cumyl hydroperoxide respectively. It was found that the faster the inhibition of the oxidation of tetralin, the higher the activity of the boric acids and their derivatives in the decomposition of tetralyl hydroperoxide. The acid strength of the boric acids was found to be much larger than that known as Brönsted acids. It was concluded that the boric acids acted as Lewis acids and not as Brönsted acids in the decomposition of aromatic hydroperoxides.

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The kinetics of the oxidation of coked silica-alumina catalysts in an air-nitrogen stream was studied under differential reactor conditions at atmospheric pressure and from 467°C to 560°C. The rates of the reaction were evaluated from the experimental data, according to a proposed kinetic model which includes coupled reactions of carbon and hydrogen in coke, and the catalytic oxidation of the carbon monoxide formed. They were then correlated with variables such as carbon content, hydrogen content, oxygen partial pressure, etc.
In addition, to examine the applicability of the rate equations obtained, the product concentration profiles for various contact times of the feed gas were observed under isothermal integral reactor conditions, and were compared with the calculated values from the material balance equations combined with the rate equations.

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Several reactions containing alcohol which has both acidic and basic characters were carried out over acid-base bifunctional catalysts. The reactions applied here were (1) dehydration and dehydrogenation of alcohols, (2) hydrogen transfer between alcohols and acetone and (3) butadiene formation from ethanol.
The reaction paths and the roles of acidic and basic sites were clarified taking into account the relationship between the reactivities of alcohols and the structure of them and the correlation of catalytic activities with their acid-base properties. Based on these results, the principles how to select the optimum catalyst was proposed. In order to obtain the optimum catalyst, it is necessary to control the acid-base properties of the catalysts taking into consideration the character of the reactive group in the molecules and the rate determining step.

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This study was conducted to determine the precise optimum atomic ratio of Co to Mo, at which the activity of hydrodesulfurization over Co-Mo-Al₂O₃ is maximum. For this purpose, over a series of catalysts, which are preferable with respect to the uniformity of impregnants and in which the concentrations of impregnants were varied in wide range of from about 3 to 16wt% of MoO₃ and from 0 to 6wt% of CoO, the hydrodesulfurization activities were measured. It was shown that the optimum ratio of Co to Mo depends to a significant extent upon the concentration of impregnated MoO₃. This result was discussed on the basis of the fact that the dispersed state of MoO₃ on carrier varied with the increases of the ratio and the concentration of MoO₃.

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The oxidation catalyst for producing acrylic acid by vapor phase oxidation of acrolein was investigated.
It was found that a single component catalyst was not very active, but the multi-component catalyst was improved in activity and selectivity.
In regard to the activities over certain types of multi-component catalysts, the volcano-type correlation between the consumption rate of acrolein and ΔH₀, which is the heat of formation at each additive component, was observed, and maximum consumption rate of acrolein was found in the range of 60∼80kcal mol^-1 in ΔH₀.
In addition, this reaction with catalysts containing at least one member of the group of Mo, W or V appears to proceed principally by a consecutive path via acrylic acid, and, on the basis of the increase of Brönsted acidity of these catalysts, the following step in the formation of carboxylic acid was suggested.

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The oxidative dehydrogenation of C₄, C₅ olefins over bismuth molybdate catalyst has been investigated by a flow method and a pulse technique. The isomers of pentene were found to be less reactive than those of corresponding butenes in the case of using the flow method, but the reverse result was obtained by means of a pulse technique. The activation energy of the reaction obtained by the former was much larger than that of the latter. The value of activation energy obtained by the pulse technique varied from 11kcal•mol^-1 to 23kcal•mol^-1 with the amount of isoprene added to the pulse of 1-butene. It was found that the reaction was strongly inhibited by isoprene added. The heat of adsorption of olefins and dienes was also measured by the gaschromatographic method.
From these results, it was suggested that the active sites of bismuth molybdate catalyst were ununiformity. The pulse reaction proceeded on the strong active sites which were inhibited by the products in the flow reaction, and the mild active sites which had a similar activity were only effective for the flow reaction.

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Dew-points were determined of the systems hydrogen+carbon monoxide+methane+carbon dioxide+propane and hydrogen+carbon monoxide+methane+carbon dioxide+n-butane at a temperature of 0°C and a pressure range of 8 to 46kg/cm²•G. In the determination of dewpoint two sets of composition of propane- or n-butane-free quaternary gas mixtures were tested. The experimental results were treated as the vapor phase solubility of propane or n-butane into quaternary mixtures. The estimations of dew-point and vapor-liquid equilibrium constants were made by the Chao-Seader and the BWR methods. For estimations of dew-point, deviations were 5 to 10°C from the experimental data.

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