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A new, reusable palladium/magnesium-lanthanum mixed oxide catalyst has been found to exhibit unprecedented high catalytic activity and selectivity for the heterogeneous Heck cross-coupling reaction of aryl halides with alkenes. The nature of the aryl halides has a determinate effect on the reaction yield. The corresponding reactions of a wide range of activated and non-activated aryl bromides and chlorides furnished the arylated product with high E/Z isomer ratios even already at 80 8C. The stereoselectivity depended on the nature of the olefins.

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A new, reusable Pd/MgLa mixed oxide catalyst has been applied successfully in the Suzuki-Miyaura carbon-carbon cross-coupling reaction of aryl halides as well as benzylic bromide with boronic acids in ethanol. The catalyst is air stable, can be stored and handled under an ambient atmosphere and after the reaction it can be recovered by simple filtration and reused without significant loss of activity.

Carbonation of industrial wastes rich in earth-alkali oxides is found to have a significant potential for CO2 sequestration. This process opens new perspectives not only for carbon dioxide mitigation, but also for the valorization and new applications of industrial waste materials from coal-burning power 2 plants. In this study, mineral carbonation of high-calcium fly ash is investigated under dry and moist conditions in a continuous flow reactor during up to 2 hours, at temperatures ranging from 160 to 290 ºC and CO2 pressures between 1 and 6 bar. A comprehensive charaterization of treated and untreated samples was carried out before and after carbonation using X-ray diffraction, X-ray fluorescence spectroscopy, thermogravimetric analysis, infrared spectroscopy and scanning electron microscopy. The maximum sequestration capacity achieved was 117.7 g CO2/kg fly ash (48.14 % carbonation efficiency) under dry conditions. Results showed that increasing the pressure and temperature enhances the process of carbonation, as well as the presence of moderate amounts of water vapor in the CO2 gas flow. Newly formed carbonates were always present in the treated samples. This study shows that about 21% of all CO2 emissions of a coal-burning power plant could potentially be sequestered as carbonates.

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