The dry desulphurization test plant with active carbon was estabilshed and was operated continuously for 1, 200 hours. The capacity of test plant for flue gases treatment was 1, 200Nm³/hr. The adsorber consisted of the cross flow type traveling bed system where the active carbon moved downward very slowly, the flue gases were conducted cross way to the flowing direction of active carbon, and the active carbon adsorbed sulphur dioxide contained in the flue gases.
The active carbon which has chemically adsorbed sulphur dioxide was treated by superheated steam in the travelling bed type desorber to desorb sulphur dioxide.
The test plant was operated almost smoothly throughouthe continuous operation period. However, decrease in degree of desulphurization was observed. It is considered that the decrease in the degree of desulphurization was caused by deterioration in sulphur dioxide adsorbing capacity of the active carbon. There are two kinds of loss in active carbon, namely, mechanicaloss and chemical loss. As the results of this experiment, the latter was larger than the former.

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Variation of properties of active carbon used in continuous run of a test plant employing the active carbon process using steam desorption was measured, and the relationship between these properties and sulphur dioxide adsorption capacity was studied.
During the continuous run, the porous structure of active carbon developed, and the BET surface area expanded slightly. The total oxygen content of active carbon also increased. Thus it reached at 17.6wt% being over two times of that in the original active carbon after 1, 200 hours. The oxygen existed mainly as surface oxides in active carbon. The surface oxides were classified into basic surface group and acidic surface group for quantitative analysis. The results indicated decrease in the amount of basic surface group and increase in the acidic surface group.
The sulphur dioxide adsorption capacity of active carbon did not show a relationship with its structural properties. It was found that the adsorption capacity is influenced by the chemical properties of surface oxides.
It was estimated that the basic surface group functions as the activation point of chemisorption with oxidation for sulphur dioxide adsorption.

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As a way to clarify the causes for deterioration of sulphur dioxide adsorption capacity of active carbon, the environmental conditions which bring deterioration to active carbon were investigated. The results indicated that exposure to oxygen at a temperature level of around 300°C gives large influence on sulphur dioxide adsorption capacity of active carbon.
Consequently, the relationship among the degree of activity for sulphur dioxide, concentration of oxygen in the atmosphere, temperature of the gas, and exposure time to oxygen was investigated. The results clarified that all these factors are related to deterioration of the degree of activity.
Then, regeneration method of the deteriorated active carbon was studied, that is, the deteriorated active carbon was heated at 300∼800°C in the various surrounding gases.
After this treatment, change in sulphur dioxide adsorption capacity of active carbon was investigated. It was clarified that the deteriorated active carbon is regenerated nearly to the initial capacity of original active carbon when heated at 550°C and 730°C respectively in the hydrogen stream and the other gases.

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The catalysts used for the long run activity tests of hydrodesulfurization reaction of the residual fuel were regenerated by burning with air. Physical properties and the desulfurization activity of the regenerated catalysts were studied. From the experimental results, the following conclusions were obtained.
1) The specific surface area of the catalysts used for the long run activity tests decreased to 40% of the original value of the fresh catalysts. The specific surface area after regeneration recovered up to 50% in the upper part of the catalyst bed and about 70% in the lower part. The specific surface area of the catalysts after about 100 hours on stream was almost completely regenerated. The pore volume also varied in proportion to the degree of recovery of the specific surface area. The mean pore diameter became greater than that of the fresh catalyst by regeneration.
2) The pore size distribution varied remarkably during the 100 hours on stream from the start, and after which it maintained almost the same distribution. Pores were plugged up by the deposited carbon and metals on the surface of the catalyst. Sites of the plugged up pores were considered to be different with different catalysts. The pore size distribution recovered more at the upper part of the catalyst bed than at the lower part after regeneration.
3) When the decrease in the catalyst activity was caused by the deposited carbon, the major part of the activity was recovered after regeneration. However, when the decrease in the activity was due to the deposited metals like vanadium etc., the activity was not recovered, since the metals could not be removed by regeneration.

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The corrosion reaction of iron wire and the effect of tensile stress on the reaction were investigated in a hydrocarbon oil and hydrocarbon solution containing sulfur compounds using the hot wire method.
The corrosion rate followed the parabolic law after an initial stage in white oil and elementary sulfur solutions. The diffusion of reactant through the formed film on the iron wire is considered to be the rate-determining step. Generally the tensile stress applied to iron wire accelerated the corrosion reaction. It seems to be the effect of stress-induced heterogeneity in the formed film.
Corrosion observed in the case of benzyl mercaptan solutions was significantly higher than other sulfur compounds, and the corrosion rate followed linear relationships. In this case the effect of tensile stress was not observed clearly because of high corrosion rate.
With dibenzyl disulfide the corrosion did not follow any of the known relationships. To understand the mechanism further, similar experiments were conducted in nitrogen atmosphere. Corrosion occured severely on iron surface in nitrogen atmosphere as compared to air.
The reaction products on the wire surface were analysed by X-ray diffraction method to deduce the corrosion mechanism.

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Catalytic activities of the molten metals, i. e. zinc, gallium and indium were measured by employing the dehydrogenation reactions of alcohols (ethanol, n-, isopropanol, allylalcohol, cyclohexanol, benzylalcohol) as the test reaction.
Except allylalcohol which converted considerably to propionaldehyde via a side reaction, all alcohols were dehydrogenated with considerably high selectivities by the molten metal catalysts. Among the three molten metals, the molten zinc showed the highest activity for all alcohols. Further, the molten zinc showed the highest selectivity for the dehydrogenation of almost all alcohols except ethanol.
From the experimental data, the first order kinetic parameter E (activation energy) and A (frequency factor) were evaluated. A single straight line log A-E relationship was found to hold not only for the data of the present work but also for the data of the preceding work (data for butanols).

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The synthetic coking coal, which is obtained from the selected virgin crude or the thermal tar pitch by means of their processing and conditioning at a critical temperature range, shows typical behaviours of coking similar with those of natural coking coal on heating up to about 1, 000°C. The synthetic coking coal has high fluidity and a wide fluidity temperature range. Coke, which is obtained from the synthetic coal or its blend with natural coal, shows excellent drum strength, reactivity with CO₂ and abrasion. The merit of the synthetic coking coal lies in that characteristics of whatever kind one may desire is obtainable by selecting conditions for preparation and original materials.

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Carboxylation of isobutylene (I. B.) and its oligomers (dimers∼tetramers) in the presence of BF₃-H₂O complex catalysts having 0.4∼1.0 BF₃/H₂O molar ratios was conducted in a heterogeneous liquid phase (solvent layer and catalyst layer) at 80∼140°C under CO atmosphere (50kg/cm²).
Trimethylacetic acid (T. M. A. A.) was obtained as the main product together with C₆, C₈, C₉, C₁₃ acids and isobutylene oligomers.
The rate of absorption of CO increased with the increase of BF₃/H₂O molar ratio of the catalyst. Carboxylic acids produced were usually distributed between solvent layer and catalyst layer, and the product distribution between both layers was greatly affected both by the BF₃/H₂O molar ratio of the catalyst and by reaction temperature. Total yield of carboxylic acids had the tendency to decrease with the higher reaction temperature with using catalyst of 0.5∼1.0 BF₃/H₂O molar ratios, but in the case of catalyst of molar ratio lower than 0.5 BF₃/H₂O, the yield of carboxylic acids increased along with the reaction temperature.
Although the mode of addition of water to the reaction mixture did not show an appreciable effect on the total amount of carboxyl group in the products, it had an appreciable effect on the T. M. A. A. content in the acids produced.
The effect of reaction time on the distribution of the products was studied too. In the early stage of the reaction, the larger part of I. B. introduced was converted into I. B. oligomers and the amount of I. B. used for the formation of carboxylic acids was comparatively small. In this stage the C₉ acid content in the carboxylic acids produced predominated over that of T. M. A. A., C₆ and C₈, and C₁₃ acids were also produced in appreciable amounts. However, in the latter stage of the reaction, the yield of carboxylic acids and the content of T. M. A. A. in the products increased at the expense of I. B. oligomers. The change in the composition of C₉ acids in the course of the reaction was also observed.
Based on the results obtained, the reaction scheme for carboxylation of isobutylene and its oligomers was discussed.

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Disproportionation of propylene on MoO₃ catalysts supported on various carriers was studied by a flow method and a pulse reaction technique. The effects of pretreatment of catalyst with various gases and of various supports on the reaction results were investigated in order to clarify the formation of active centers of catalyst.
When pretreated with nitrogen, the activities of the various catalysts were dependent on the carrier used. Reduction of these catalysts with hydrogen before the reaction caused a marked increase in their activities.
The activities of catalysts were correlated with ESR intensities of Mo⁺⁵ and the amount of CO adsorbed. A linear relationship between adsorbed CO and activities was obtained.
The results confirmed that the active centers were lower valency Mo ions. Though the acidic centers of the carriers play a role in forming active centers during preparation, they are not the active centers and do not participate in the reaction.

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It was the object of this study to find correlations between acidity and the activities of various reactions on decationated zeolites.
Catalytic activities of decationated zeolites were investigated in the dehydration of ethanol, alkylation of benzene with ethylene or ethanol, cracking of cumene and isomerization and disproportionation of o-xylene using a flow apparatus. Acidity and strength of acid sites on decationated zeolites were determined by amine titration.
From these observations, it was suggested that the acid site at H₀_??_+3.3 played an important role in the alkylation of benzene with ethylene or ethanol and disproportionation of o-xylene, while the acid site at H₀_??_-3.0 played an important role in the dehydration of ethanol to ethyl ether, cracking of cumene and isomerization of o-xylene.

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Anionic telomerizations of styrene with amines catalyzed by alkali metal or metals were investigated. Reactions of styrene with aliphatic primary amines afforded N-alkyl-2-phenylethylamines (I), N-alkyldi (2-phenylethyl) amines (II) and N-alkyl-2-phenylethyl-2, 4-diphenylbutylamines (III), and those of styrene with aliphatic secondary amines yielded N, N-dialkyl-2-phenylethylamines (IV), N, N-dialkyl-2, 4-diphenylbutylamines (V) and N, N-dialkyl-2, 4, 6-triphenylhexylamines (VI). N-Aryl-2-phenylethylamines (VII) and N-alkyl-N-aryl-2-phenylethylamines (VIII) were obtained by base-catalyzed reactions of this monomer with aromatic primary amines and N-alkyl aromatic amines, respectively. The structure of telomers obtained by those reactions was determined by NMR, IR, elementary analysis, mass spectrometry and vapor pressure osmometry. The scheme of the alkali-metal-catalyzed reactions was discussed from the standpoint of anionic telomerization where amine acts as a telogen and styrene reacts as a taxogen, and the effect of reactivity of amines on the yields and compositions of telomers was also discussed.

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A new three stage process to produce benzyl alcohol from toluene has been developed as a semi pilot scale plant. The third stage, that is the hydrogenation of methyl benzoate to benzyl alcohol, is discussed in this article.
Thus the study for the optimal design of the hydrogenation stage has been made on the basis of experimental process data and collected cost data. Consequently, distinguishing features of hydrogenation of methyl benzoate in commercial operation are found as shown below:
1. Reactor, hydrogen bubbling column
2. Catalyst used, copper chromium type
3. Solvent, constant b. p. mixture of methanol/toluene
4. Catalyst recovery, pressure drum filter
5. Reaction temperature, 140°C
6. Reaction pressure, 250kg/cm²•G
7. Solvent ratio, 1.96kg/benzoate kg
8. Catalyst ratio, 0.132kg/benzoate kg
9. Hydrogen superficial velocity, 1.0cm/sec
10. Conversion, ca. 30%
11. Selectivity, 95%
The new process produces benzyl alcohol of 99.9% purity at a price less than 200yen/kg at a production capacity of 600 tons/30 days.

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To import the natural gas from oversea fields will go far towards solving an unbalance between gas demand and supply. The reasonable importing cost is one of important factors for the establishment of the LNG industry, which is characterized by a highly complex system composed of interrelated functional factors. This paper deals with an actual FORTRAN program which is the simulation model on the CIF cost in the LNG importing industry and presents with an example of calculation.

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