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A highly efficient and environmentally friendly approach for the synthesis of 1,8-dioxo- octahydroxanthenes has been developed catalysed by a supported cobalt nanoparticle catalyst (CoNP@SBA-15) in water. The use of this heterogeneous catalytic system offered several advantages including high yields, low catalyst loading, short reaction times and easy workup. Furthermore, the catalyst was efficiently reused for ten consecutive cycles without any significant loss in catalytic activity.

A bifunctional nanocatalyst composed of iron containing SBA-15 material modified with sulfonic acid groups was synthesized by a mechanochemical approach. A full characterization of the obtained nanocatalyst was performed by N2 physisorption isotherms analysis, transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and Fourier-Infrared Spectroscopy (FT-IR). The mechanochemically synthesized nanocatalyst displays a high isoeugenol conversion to vanillin under mild conditions using H2O2 as oxidizing agent. Interestingly, this conversion resulted to be higher than that one obtained with the same material synthesized by an impregnation method. Additionally, the nanocatalyst showed excellent reusability over four successive runs under the studied reaction conditions.

An immobilized copper Schiff base tridentate complex was prepared in three steps from SBA-15 supports. The immobilized copper nanocatalyst (heterogeneous catalyst) was characterized by Fourier transform infrared spectroscopy (FT-IR), cross polarization magic angle spinning (CP-MAS), 13-carbon nuclear magnetic resonance (13C-NMR), atomic absorption spectroscopy (AAS), thermogravimetric analysis (TGA), and N2-physisorption. Moreover, morphological and structural features of the immobilized nanocatalyst were analyzed using transmission electron microscopy (TEM) and X-ray powder diffraction spectrometry (PXRD). After characterizing the nanocatalyst, the catalytic activity was determined in hydrogen peroxide (H2O2) decomposition. The high decomposition yield of H2O2 was obtained for low-loaded copper content materials at pH 7 and at room temperature. Furthermore, the nanocatalyst exhibited high activity and stability under the investigated conditions, and could be recovered and reused for at least five consecutive times without any significant loss in activity. No copper leaching was detected during the reaction by AAS measurements.

Zn-Co double metal cyanide (DMC) catalysts were prepared by varying the initial amounts of ZnCl2 to analyze the influence of method of preparation on the different copolymerization parameters. Synthesized catalysts were analyzed by different techniques, infrared spectrometry and inductively coupled plasma optical emission spectrometry, scanning electron microscopy, N2-physisorption and X-ray diffraction to determine whether characteristics affect the catalytic activity. The copolymers were characterized by infrared spectrometry and gel permeation chromatography. Highly active catalyst (2.5 kg polymer/g catalyst) was synthesized, low amounts of cyclic carbonate byproduct were produced (0.4 %) with medium crystallinity catalysts and considerable amounts of K+ (0.4% to 1.0%wt)., CTQ2015-64892-R (MINECO/FEDER)