In the catalytic hydrocracking of asymmetric diarylmethanes the following two reactions are possible;
Ar-CH₂-Ar'_??_ArH+H₃C-Ar'
ArCH₃+HAr'
We studied the hydrocracking behavior of asymmetric polymethyldiphenyImethanes using CoO-MoO₃-Al₂O₃ as catalyst, and clarified the influence of methyl substituent on the hydrocracking behavior.
Results obtained can be summarized as follows;
1. In the hydrocracking of monomethyldiphenylmethanes the formation of toluene was greater than that of benzene and xylene. This shows that the fission between methylene group and methyl-substituted phenyl group occurs predominantly.
In the hydrocracking of C₆H₄-CH₂-C₆H_5-n(CH₃)_n the priority of the fission between methylene group and C₆H_3-n(CH₃)_n increased with increasing the number of methyl group.
In the hydrocracking of (CH₃)_nC₆H_5-n-CH₂-C₆H_3-m(CH₃)_m, where n was larger than m, the fission between methylene group and (CH₃)_mC₆H_5-n occurs predominantly.
2. The influence of the position of methyl group on the hydrocracking behavior was as follows.
In the hydrocracking of C₆H₃-CH₂-C₆H₄CH₃ the fission between methylene group and C₆H₄CH₃ was favorable in the order of o-CH₃>>p-CH₃≥m-CH₃.
When two methyl groups occupied two ortho positions in the same aromatic ring, the degree of the fission between methylene group and o, o-disubstituted aromatic ring remarkably increased.
3. The ratio of fission between methylene group and two aryl groups of asymmetric diarylmethane could be estimated by the relative values of two phenylarylmethanes from which asymmetric diarylmethane was constituted.
4. An empirical equation on the hydrocracking behavior of asymmetric diarylmethanes was introduced, and this equation fitted with the experimental data except in a few cases.
5. It was found that there was a relationship between logarithm of relative stability of π-complex (HCl) of Ar-CH₃ and that of Ar'-CH₃ when diarylmethanes were indicated as Ar-CH₂-Ar', and logarithm of relative fission between methylene group and aryl groups.

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The most highly alkali containing alkali polyaluminate, so called β"-Al₂O₃, was selected, and used as a catalyst for catalytic cracking of naphtha, kerosene and gas oil, using a flow reactor, and the following results were obtained. A maximum yield of ethylene from naphtha was 47.27%, under the operating conditions of 800°C, steam/oil ratio 3.0 and space velocity 7, that from kerosene was 37.51% and that from gas oil was 36.69%, under the operating conditions of 800°C, steam/oil ratio 3.0 and space velocity 5. The effect of reacting temperature, space velocity and steam/oil ratio on the yield of cracking products were similar to pyrolysis, and there were definitive correlations among reacting temperature, space velocity and maximum yield of cracking products. In naphtha cracking, carbon residues were removed from catalyst surface under steam/oil of ratio 1.5ml/g or more, and in case of kerosene and gas oil cracking steam/oil ratio of 3.0ml/g was needed. It is considered that the action of this catalyst is to accelerate the thermal cracking of hydrocarbon as a thermal medium, to increase the rate of removing carbon residues from catalyst surface by steam gasification, to attain a close approach to equilibrium of the shift reaction and to maintain the ratio of (CO)²/(CO₂) below the critical values for carbon formation.

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The relationship between the activity of molybdenum-rich MoO₃-SnO₂ catalyst for the oxidation of ethylbenzene and its structure was studied. It was found that the binary catalyst containing small amount of SnO₂ (Sn/Mo=0.025-0.2, atomic ratio) showed higher activity than MoO₃ or SnO₂ catalyst. No solid solution or chemical compound other than molybdenum trioxide or stannic oxide was observed in the binary catalyst by means of X-ray diffraction, DTA or IR spectroscopy. On the other hand, according to the results of X-ray diffraction, it was considered that the smaller crystallites of stannic oxide, which are almost the same size with the different composition of the catalysts, are dispersed on the surface of the larger crystallites of molybdenum trioxide. ESR spectra of the binary catalyst showed that the amount of Mo⁵⁺ are proportional to that of SnO₂ in the catalyst. From these points, it is considered to be reasonable that the Mo⁵⁺ ions exist along the boundaries of two kinds of oxide and Mo⁵⁺ ions near the surface worked as the active centre for ethylbenzene oxidation.

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Physical properties of asphalt were measured as function of concentration with SBR latex which contains 15% (But-15) to 100% of butadiene (But-100), and compatibility between asphalt and various latexes was discussed with solubility parameter of maltens determined by NMR structural analysis and Small's equation.
The following results were obtained,
1) Penetration index of asphalt was improved with 75% butadiene (But-75) and But-100, but But-15 was more effective in lowering penetration rather than penetration index.
2) From the results obtained by penetration and viscosity measurements, it was confirmed that the effect of improvement on properties of asphalt depended on compatibility between asphalt and latex, but that the compatibility was poor in case of But-15.
3) The value for solubility parameter of maltens calculated from an average structure of malten molecule and Small's equation was approximately 8.30, and this value agreed closely with solubility parameter of latexes (But-75 and But-100) which have good compatibility with asphalt.

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In the condensation of 1, 2, 4-trimethylbenzene (1, 2, 4-TMB) with formaldehyde bis (2, 4, 5-trimethylphenyl) methane was formed as the main product while a few asymmetric hexamethyldiphenylmethanes (HeMDPM) such as 2, 3, 6, 2', 4', 5'-HeMDPM were formed as by-products.
The reaction of 1, 2, 4-TMB with 2, 4, 5-trimethylbenzylalcohol (2, 4, 5-TMBA) and/or the reaction of 1, 2, 4-TMB with 2, 3, 6-TMBA are assumed, as the routes for the formation of 2, 3, 6, 2', 4', 5'-He MDPM. These TMBA are produced as primary products in the condensation of 1, 2, 4-TMB with formaldehyde.
To clarify the scheme of the condensation, we determined product distributions in the reaction of 1, 2, 4-TMB with formaldehyde, 2, 4, 5-TMBA and 2, 3, 6-TMBA respectively, and obtained the following results.
1) The product distribution in the condensation of 1, 2, 4-TMB with formaldehyde was 2, 4, 5, 2', 4', 5'-84%, 2, 3, 6, 2', 4', 5'-15%, 2, 3, 6, 2', 3', 6'-0.6%, and 2, 3, 5, 2', 4', 5'-HeMDPM 0.4%.
2) The distribution of TMBA formed as an intermediate product in the condensation reaction was 2, 4, 5-96%, 2, 3, 6-3.8% and 2, 3, 5-0.2%.
3) The distribution of HeMDPM formed in the reaction of 1, 2, 4-TMB with 2, 4, 5-TMBA was 2, 4, 5, 2', 4', 5'-87%, 2, 3, 6, 2', 4', 5'-12% and 2, 3, 5, 2', 4', 5'-0.2%.
4) 2, 3, 6, 2', 4', 5'-HeMDPM, a primary asymmetric product formed in the condensation of 1, 2, 4-TMB with formaldehyde, was formed predominantly through the reaction of 1, 2, 4-TMB with 2, 4, 5 TMBA.

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