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Copyright of Revista CIENCIA UNEMI is the property of Universidad Estatal de Milagro (UNEMI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This document presents a brief history of catalysis, as well as of the selective oxidation processes of hydrocarbons. On the other hand, the basic concepts involved in heterogeneous catalysis are addressed, emphasizing the role of catalytic materials in chemical oxidation processes and posing a series of guiding questions that must be followed when addressing a process catalyzed by solid materials. In the same way, the preparation methods known in the literature as sol-gel and impregnation are shown, identifying the influence of each preparation step with the physical and chemical properties of the materials. Finally, a case study applied to the selective catalytic oxidation of methane and methanol using iron, molybdenum, and vanadium catalytic materials synthesized by the sol-gel method is presented. [ABSTRACT FROM AUTHOR]

In this work we performed the synthesis and characterization of salen-type catalysts with Zn, which were obtained by condensation reaction between a 1,2-diamine and 3,5- ditertbutylsalicylaldehyde in the presence of zinc acetate. We reported yields of 86% in the synthesis of catalyst Zn-salen-1, 60% for Zn-salen-2 and 70% for Zn-salen-3. These catalysts were tested in the coupling reaction between CO2 and limonene oxide. The best results in terms of conversion (20%) were achieved when the catalytic system Zn-salen-2/NBuI was evaluated under 20 bar of CO2, 40 °C for 24h. In all cases studied, the reaction was completely selective towards the poly(limonene) carbonate formation. There was no significant dependence of CO2 pressure on the determination of the activity of the catalytic system examined. [ABSTRACT FROM AUTHOR]

Copyright of Scientia et Technica is the property of Scientia et Technica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)