Pseudocumene was isopropylated by using an isopropyl aromatic sulfonate as alkylation agent. This reaction proceeded rapidly at the temperature of 120-130°C. The crude product contained 3-, 5-, and 6-isopropyl pseudocumene in the ratio of about 4:68:28. It was found that the same reaction also proceeded with pseudocumene and propylene when aromatic sulfonic acid was added as catalyst. Mono isopropyl pseudocumene could be obtained, as the main product of this catalysed reaction, by controlling reaction conditions, and the ratio of three isomers in it was not influenced by the reaction time. These results show that the above isopropylation is different in reaction mechanism from the isopropylation catalysed by Lewis acid or sulfuric acid. 5-isopropyl pseudocumene was effectively separated by washing the reaction mixture with sulfuric acid. After purification of the isopropylated product, 5-isopropyl pseudocumene with 95% purity was obtained, and its yield was about 65mol% based on pseudocumene fed under the optimum conditions.

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Reforming reaction of Methylcyclopentane (MCP) over Pt/Al₂O₃/Cl type catalyst was investigated under the conditions of the industrial use, such as reaction temperature; 480-520°C, total pressure; 20-44.5atm, Liquid Hourly Space Velocity; 5.99-34.83vol/vol•hr, and supply ratio of H₂/MCP; 5-15mol/mol. The following conclusions were obtained.
(1) Two kinds of reaction paths are considered; one is the dehydro-ring isomerization-aromatization process which produces Methylcyclopentene, Benzene and Cyclohexane, and the other is the ring opening process which produces Hexanes.
(2) In the initial MCP-reforming reaction, the rate determining step in the dehydro-aromatization reaction is the process where Methylcyclopentyl (MCP•) adsorbed on Pt-site dissociates one hydrogen, and the rate determining step in the ring opening reaction is the process where hydrogenolysis of (MCP•) adsorbed on Pt-site takes place by dissociated hydrogen.
(3) Initial reaction rate equations of dehydro-aromatization [v_0(MCP=_+Arom)] and of hydro-ring opening [v_{0(Ring open)}] can be expressed by equation (A) and (B). The equations (A) and (B) satisfy the experimental data respectively.
v_0(MCP=_+Arom)=k_(Arom)K_(MCP•)p_MCP/p_H2^1/2/[1+K_(MCP•)p_MCP/p_H2^1/2]² (A) v_{0(Ring open)}=k_(open)K_(MCP•)p_MCP/[1+K_(MCP•)p_MCP/p_H2^1/2]² (B)
(4) Activation energy (E) and heat of adsorption (Q) are calculated as follows;
E_(MCP=_+Arom)=32.6, E_{(Ring open)}=38.5, Q_(MCP•)=2.5-2.6(kcal/mol).

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Because of its outstanding strength at elevated temperaturs and resistivity to intergranular corrosion, stabilized austenitic stainless steel has been widely used throughout the petroleum and petrochemical industries. Recently, however, authors have experienced the embrittlement of commercial stabilized austenitic stainless steel after long time service at temperatures between 600°C and 800°C. It was found through an examination that the embrittlement was remarkable in a zone affected by the welding heat cracking occasionally occurring by tensile stress such as thermal stress in the embrittled heat affected zone. Authors studied on the properties of embrittled material and the cause of cracking. The results obtained were as follows;
1) The crack takes place in the base metal within 0.5-1mm distance from the welding fusion line, and is mainly intergranular cracking.
2) It is found that a let of fine needle-shaped carbide precipitated near the crack, and it seems that there is some correlation between needle-shaped carbide and cracking.
3) A high temperature tensile test at 650°C shows that the embrittled zone has ductility large enough for normal austenitic stainless steel type AISI 321.
4) Judging from the above fact, the cracking is caused by coincidence of low ductility of the material at lower temperatures and arrest of creep phenomenon accompanied by precipitation of carbide, and thermal stress. Accordingly, the cracking may be prevented by relief of concentration of stress and thermal stress.
5) And then, the embrittlement after long time service at elevated temperatures may be recovered by solution heat treatment.

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The vapor phase catalytic synthesis of aniline from phenol and ammonia over some catalysts has been studied in a flow reactor under atmospheric pressure. Activity tests were carried out at a temperature range of 380-530°C, a W/F ratio of 3.7g cat•hr/mol total-feed and 3 mole ratio of ammonia/phenol. The order of catalyst activities at 450°C was found to be as follows:
SiO₂-Al₂O₃(25%Al₂O₃)>>SiO₂-Al₂O₃(13%Al₂O₃)>5%F-SiO₂-Al₂O₃(13%Al₂O₃)>7.5%F-SiO₂-Al₂O₃(25%Al₂O₃)>CaY zeolite>>γ-Al₂O₃.
SiO₂-MgO, Ca phosphate and NaY zeolite were virtually inactive. The activities of these catalysts were reasonably correlated with the heat of adsorption of phenol on their surfaces determined gas-chromatographically, showing that the adsorption of phenol on the catalyst plays an important role in this reaction. A kinetic experiment on the most effective catalyst SiO₂-Al₂O₃ (25%Al₂O₃) at 500°C using a differential reactor technique indicated that the rate of the production of aniline was proportional to p_NH3 at a partial pressure range of phenol of 0.4-0.6atm and to p_NH3•p^1/2_{C_??_H_??_O_??_} at that of phenol of 0.04-0.09atm. The partial pressure dependency on the rate was explained according to the Rideal-Eley mechanism, involving a surface reaction between phenol chemisorbed and ammonia physically adsorbed or in bulk gas phase.

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The thermal decomposition of propane has been studied in an argon-hydrogen microwave plasma jet at 470W and 1atm. Propane was fed perpendicular to a plasma jet axis at 12mm from a nozzle of plasma torch gun. The local products distribution in the plasma jet was studied using a probe. Main products were acetylene, carbon, ethylene, methane and hydrogen. Besides a little amount of propylene was also formed. It has been found that estimated propane concentration reached maximum at 10mm section on central axis of the reactor, and then diffused to mix perfectly with the plasma jet at 30-40mm Section.
Furthermore, in 0mm section, propane scarcely reached beyond radius of 5mm perpendicular to the axis connecting both propane inlets. On central axis of plasma jet, the conversion of propane was high at 0mm section, but decreased with the increase of axial distance. Downstream from 20mm section, the profile of the conversion showed a tendency similar to that of the other measured position.

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