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The solubility of thiotriazinone in water, methanol, ethanol, water + methanol, and water + ethanol has been measured under temperatures ranging from (283 to 330) K with a laser technique. The results of these measurements were correlated with semiempirical equations. The calculated results have showed fine representativity of experimental data. The stepwise regression method was used to simplify the modified Jouyban–Acree equation.

Cadmium modified HZSM-5 catalyst (Cd/ZSM-5) prepared by incipient wetness impregnation shows markedly high selectivity of aromatics and low selectivity of light alkanes and C5–C9 nonaromatics in the methanol-to-aromatics (MTA) transformation. The majority of the introduced Cd cations can exchange with protons of the bridged hydroxyl groups of HZSM-5, leading to a reduced number of Brønsted acid sites while generating new Lewis acid sites on the catalysts. The selectivity of aromatics with the Cd/ZSM-5 is found to be linearly correlated with the concentration of the strong Lewis acid sites. Compared to Zn/ZSM-5, the most extensively investigated catalyst thus far for the MTA, Cd/ZSM-5 is found to be more effective in promoting the aromatics formation. The different catalytic behavior observed for Cd/ZSM-5 and Zn/ZSM-5 catalysts is most likely due to the difference in ionic radius of Cd and Zn.

Alkali metal oxides supported on SBA-15, M/ SBA-15 (M = Li, Na, K, Rb, and Cs), prepared by the impregnation method were characterized and tested for the aldol condensation of methyl acetate and formaldehyde to methyl acrylate (MA). M/SBA-15 catalysts are active for the formation of MA while the support is inert. The supported alkali metals react with hydroxyl groups on SBA-15 by replacing the H atoms and generate weak and medium basic sites. The latter plays an important role in promoting the reaction. Coke formation results in deactivation of Cs/SBA-15, and the deactivated catalyst can be regenerated by burning off the coke. Two possible reaction pathways for the formation of MA were explored using quantum calculations. The predicated activity for M/SBA-15 is consistent with the experimental observations. A pathway with adsorbed enol molecule as an intermediate was suggested to be predominant for the formation of MA.