Los avances tecnológicos han permitido diversificar y optimizar la producción de ener-gía, lo que ha conducido al mismo tiempo, a desarrollar nuevas vías de almacenamiento de la misma. En particular, a medida que se diversifican los métodos de producción energética, es necesario desarrollar nuevos materiales para almacenamiento de energía, para su uso en dispositivos de…
Se pretende desarrollar óxidos eutécticos binarios y ternarios basados en la alúmina –en concreto, Al2O3/ZrO2, Al2O3/Y3Al5O12(YAG), Al2O3/ZrO2/YAG y Al2O3/SiO2/ZrO2, con la circona estabilizada con diferentes contenidos de Y2O3– con microestructuras controladas en el intervalo micro- a nanométrico, para su empleo en aplicaciones estructurales y térmicas de sistemas de generación y conversión más eficientes de la…
The sorption reversibility of La and Lu (considered as actinide analogues) onto a set of smectites (bentonite FEBEX; hectorite, HEC; MX80; saponite, SAP; Otay montmorillonite, SCa-3; and Texas montmorillonite, STx-1) was studied to estimate actinide retention by smectites that are candidates for use as engineered barriers in deep geological repositories. The sorption distribution coefficients (K…
A mimetic polymer of plant cutin have been synthesized from 9,10,16-trihydroxyhexadecanoic (aleuritic) acid through a low temperature polycondensation reaction. Reaction conditions (solvent, catalyst, temperature, etc…) were studied and modified to optimize yield and product characteristics. The resulting polyaleurate polymer was characterized by Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Differential Scanning Calorimetry (DSC), X-ray Diffraction…
Kalsilite (the low-temperature form of KAlSiO4) is used as the precursor of leucite, an important component in porcelain-fused-to-metal and ceramic-restoration systems, and it has also been proposed as a high-thermal expansion ceramic for bonding to metals. The present study reports the hydrothermal synthesis and characterization of pure kalsilite from kaolinite in subcritical conditions, as well…
This study reports a simple method to synthesize pure kalsilite (KAlSiO4) using readily available precursors, kaolinite and KOH solution, after only 12 h of hydrothermal treatment in mild conditions. A structural refinement has been carried out using the Rietveld method to obtain unit cell parameters, and the 29Si and 27Al magic angle spinning nuclear magnetic…
The Deep Geological Repository (DGR) concept involves the placement of long-lived radioactive waste in rooms excavated deep. The major responsibility of the disposal safety falls on the Engineered Barrier System (EBS). The main constituent of EBS is bentonite that prevents the release of radiactive nuclei by physical and chemical mechanisms. The physical mechanism is expected…
Mineralogical changes in a set of phyllosilicates, differing in their layer nature, chemical composition, octahedral character, and Al content of the tetrahedral sheet, were analyzed after hydrothermal reaction in an alkaline solution. The composition of the alkaline solution was selected to simulate the first stage of cement degradation [NaOH-KOH-Ca(OH)2]. The reaction products have been analyzed…
This paper presents the results of a comprehensive investigation of the interaction of layered silicates with Ca(OH)2 in hydrothermal conditions. The study is intended to evaluate the stability of the clay buffer in radioactive waste repositories, at the intermediate stages of concrete leaching, when the pH is controlled by the dissolution of portlandite. The influence…
9(10),16-Dihydroxypalmitic acid (diHPA) is a particularly interesting polyhydroxylated fatty acid (1) because it is the main monomer of cutin, the most abundant biopolyester in nature, and (2) because the presence of a terminal and a secondary hydroxyl group in midchain positions provides an excellent model to study their intermolecular interactions in a confined phase such…