No abstract

h i g h l i g h t s " Kinetic model for nopol synthesis based on the Langmuir-Hinshelwood formalism is obtained. " The main product, nopol, inhibits the activity of the Sn-MCM-41. " The rate law is robust respect to equilibrium adsorption constants. " The effect of temperature on kinetic of nopol synthesis is mainly on the surface reaction constant.

No abstract

The palladium on alumina (Pd@Al2O3)‐catalyzed hydrogenation of allylbenzene to propylbenzene was studied in methanol and aqueous micellar solutions of sodium dodecyl sulfate (SDS), decyltrimethylammonium bromide (DTAB), and t‐octylphenoxypolyethoxyethanol (TX‐100). Over Pd@Al2O3, propylbenzene was obtained via direct hydrogenation of allylbenzene and isomerization to β‐methylstyrene which was hydrogenated afterwards. In aqueous micellar solutions, the reaction was faster than in pure water, but slower than in methanol due to lower hydrogen solubility. In the H2O/SDS system, a higher activation energy was obtained than in methanol. For the investigated surfactants, the initial reaction rate in the micellar systems decreased in the order SDS > TX‐100 > DTAB.

Se comparó la actividad de Sn-MCM-41 y Sn-SBA-15 para la síntesis de nopol a partir de β-pineno yparaformaldehído. Los materiales se prepararon por los métodos hidrotérmico y el de impregnaciónhúmeda incipiente, utilizando cloruro estañoso como sal precursora de Sn. Los catalizadores sintetizados por impregnación presentaron mayor actividad y fueron más selectivos a nopol que los materialesobtenidos por el método hidrotérmico. La conversión de β-pineno obtenida con Sn-MCM-41 fue similar ala obtenida con Sn-SBA-15. Mediante síntesis hidrotérmica, se obtuvo especies de Sn(IV) en forma deagregados de SnO y substituyendo isomórficamente Si en la MCM-41 y la SBA-15, respectivamente.