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In this paper we report experimental and theoretical studies concerning the thermal behavior of some organotin-Ti(IV) oxides employed as precursors for TiO(2)/SnO(2) semiconducting based composites, with photocatalytic properties. The organotin-TiO(2) supported materials were obtained by chemical reactions of SnBu(3)Cl (Bu = butyl), TiCl(4) with NH(4)OH in ethanol, in order to impregnate organotin oxide in a TiO(2) matrix. A theoretical model was developed to support experimental procedures. The kinetics parameters: frequency factor (A), activation energy, and reaction order (n) can be estimated through artificial intelligence methods. Genetic algorithm, fuzzy logic, and Petri neural nets were used in order to determine the kinetic parameters as a function of temperature. With this in mind, three precursors were prepared in order to obtain composites with Sn/TiO(2) ratios of 0% (1), 15% (2), and 30% (3) in weight, respectively. The thermal behavior of products (1-3) was studied by thermogravimetric experiments in oxygen.

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This article presents the study of CO2 capture through aqueous solutions with high basicity conditions. Systematic experiments were conducted to assess the performance of alcohols mixed with aqueous alkaline hydroxides for carbon dioxide capture. Alcohols can work as a catalyst in the capture of CO2 providing greater basicity, a lower surface tension, and an amphiphilic character in the polar aqueous solvent/ (nonpolar CO2 and N2) gas mixture interface, and a lower temperature of solvent regeneration. The results showed that short‐chain alcohols, such as methanol and ethanol, and alkaline metals of greater molar mass (i. e., K compared to Na) can produce greater basicity and a higher CO2 absorption rate in the mixtures than conventional aqueous solutions such as ammonia or monoethanolamine in the same concentration. DFT calculations of electronic and thermodynamic properties for CO2 absorption reactions were carried out to analyze the nucleophilic trend of the short‐chain alkoxides studied. The volumetric proportion between water and alcohol, as well as the concentration of alkaline hydroxide, influences the rate of CO2 absorption, the temperature of regeneration and volatility of the solvent, and the formation of precipitates. CO2 absorption rates greater than 90 % v/v and solvent regeneration temperatures of approximately 78 °C were achieved using ethanol, water, and KOH.