Syntheses and characterizations of cobalt doped mesoporous alumina prepared using natural rubber latex as template and its catalytic oxidation of tetralin to tetralone Original Research Article

Natural rubber latex, one of the most important biosynthesized polymers, was successfully used as template in the syntheses of cobalt doped mesoporous alumina. The synthesized cobalt doped mesoporous alumina was characterized by a combination of various physicochemical techniques; N2 adsorption/desorption, diffuse reflectance UV–vis, X-ray diffraction and FT-IR. It was used as an efficient catalyst for the oxidation of tetralin to 1-tetralone under mild conditions for the first time. The catalyst exhibited high substrate conversion (80.3%) and good product (1-tetralone) selectivity (74.5%). Fast hot catalyst filtration experiments proved that the catalyst acted as a heterogeneous one; it can be reused three times without losing its activity. By contrast, undoped alumina synthesized using rubber latex as template, cobalt-doped alumina synthesized by a using traditional chemical template: poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (P123) as template, and cobalt-doped mesoporous silica synthesized by using natural rubber latex as template exhibited much lower activities.