Valorisation of Coffee Roasting By-Products: Recovery of Silverskin Fat By Supercritical CO2 Extraction

Recovery of agro and food-industrial waste and their valorisation via green technologies can help to outline new concepts of industrial strategies. In this contest, a fat enriched of added-value components was extracted from cofee silverskin by applying a supercritical fuid extraction technique (sc-CO2). An appropriate modulation of process parameters like temperature (T=35, 50, 60 °C) and pressure (p=200–300 bar) infuences the fat yield and the chemical composition, opening the way for targeted extraction. The extraction time, the organic solvent use and the energy consume were reduced compared to Soxhlet. Moreover, a mathematical model was constructed based on the experimental data collected, employed apparatus, and physico-chemical characteristics of biomass, pointing to a possible industrial scale-up. The experimental results are accompanied by a preliminary cost of manufacturing (COM), highlighting how the high investment for the apparatus is compensated by several benefts

Supported copper precatalysts for ligand-free, palladium-free Sonogashira coupling reactions

Copper(II) oxide and Cu metal, highly dispersed on inert oxides ( silica, alumina), have been employed as precatalysts in ligand-free, palladium-free Sonogashira coupling reactions. Best results were obtained with highly dispersed Cu metal on alumina, which exhibited high reactivity with aryl iodides. Electron-rich alkynes, in particular arylacetylenes, act as the most effective alkyne substrates. The present catalytic system appears attractive in view of its ease of application and low cost, due to the use of a readily available non-noble metal catalyst combined with the absence of ligands

A new, Fe based, heterogeneous Lewis acid : selective isomerization of a-pinene oxide

Heterogeneous Fe supported catalysts prepared by grafting Fe(III) acetylacetonate under basic conditions onto pure silica and a series of modi\ufb01ed silicas with variable amount of zirconia were prepared. Their characterization showed the presence of Fe3+ species, with complete surface dispersion of the iron-phase and without any Fe3O4 presence. These materials exhibit not only excellent activity in the liquid phase isomerization of a-pinene oxide but also good selectivity towards campholenic aldehyde, thus showing their Lewis acid nature

Reduction and oxidation through hydrogen transfer reactions

Low loading supported copper catalysts have been used to selectively reduce saturated and unsaturated carbonyl compounds through hydrogen transfer from 2-propanol. The effect of the catalyst support and of the donor alcohol have been investigated in detail in the reduction of 4-tert-butyl-cyclohexanone allowing to put in light a dehydrogenation-hydrogenation mechanism. The dehydrogenation reaction has been used to selectively transform secondary aliphatic alcohols into ketones in the presence of styrene as hydrogen acceptor