The extraction/hydrolysis process of arabinoxylans from destarched wheat bran was studied in this work using different mesoporous silica supports and the corresponding RuCl3-based catalysts. The effects of temperature, time, catalyst supports and ruthenium catalysts were investigated and discussed in terms of the arabinoxylans extraction yield and their polymerization degree. Relatively high temperatures (180 ºC), short […]
Microwave-assisted extraction (MAE) of polyphenols from medicinal plant, Clinacanthus nutans (C.nutans) was developed. Affecting parameters on the extraction yield of polyphenols such as ethanol concentration, solvent-to-feed ratio (S/F) and energy absorbed were studied. The variations in the effect of ethanol concentration and S/F were also explained in view of energy absorption. Polyphenols yield was found […]
Three different bimetallic Ru:Ni catalysts supported on a mesoporous silica MCM-48 were prepared by consecutive wet impregnations, with a total metal loading of ca. 3 % (w·w-1). Ru:Ni ratios spanned in the range of 0.15 – 1.39 (w·w-1) and were compared with the corresponding monometallic Ni/MCM-48. The catalysts so prepared were characterized by X-Ray Diffraction, […]
The fractionation of grape seeds as a model biomass was studied using a combination of two processes: solvothermal extraction using ethanol and hydrothermal fractionation-autohydrolysis process in a semicontinuous reactor using subcritial water. Around 70% of the polyphenols were extracted in the first step and close to 80% of the sugars in the second step.
Epigallocatechin gallate (EGCG) is the catechin with the highest antioxidant activity present in green tea. Nevertheless, due its low bioavailability, it is necessary to develop EGCG formulations capable of improving its stability resulting in increased bioavailability and thus higher biological activity of this catechin (e.g. antioxidant activity). The purpose of this work was the formulation […]
New Research paper: Adsorption of nickelocene and ruthenocene on mesoporous silica MCM-48 and activated carbon supports in supercritical carbon dioxide Álvaro Sastre, Ángel Martín, Esther Alonso / J. Supercritical Fluids 117 (2016) 138-146 Available online until 24 September 2016 http://authors.elsevier.com/a/1TUxC3BwpenVpg
A process to coat nanoparticle agglomerates has been developed and its critical operation parameters have been studied in this work. It consists on a fluidized bed where a supercritical anti-solvent process (SAS) takes place. Titanium dioxide (TiO2), used as model nanoparticle, has been coated with a polymer, Pluronic F-127, from an ethanolic solution.
This work presents a methodology to characterise continuous hydrothermal flow systems both experimentally and numerically, working at low Reynolds numbers. Under these conditions traditional computational approaches in the field are of limited use, so new tools are in demand. Residence time distributions (RTD) experiments are carried out using a purpose built continuous flow rig featuring […]