Chapters authored
Microporous and Mesoporous Materials in Decontamination of Water Process
Water pollution is the main threat that confronts humanity today. The daily human activity introduces different pollutants in hydric sources that modify water quality. This represents a high production of water that is not appropriate for different applications like human consumption. Among the water pollutants more common are dyes, herbicides, pesticides, alkanes, halo alkanes, aliphatic compounds, alcohols, carboxylic acids, aromatic compounds, detergents, surfactants, inorganic compounds (heavy metals), harmful gases, and pathogenic bacteria (bacteria and virus). These pollutants can be found in underground and surface water, and therefore can produce adverse effects on the environment and human health. These effluents can be treated with different procedures such as biological and chemical treatments, among others. However, in some cases, these processes are not appropriate for compliance legislation. Thus, adsorption with special materials such as carbon aerogels and advance oxidation processes such as photocatalysis are widely studied nowadays.
Part of the book: Microporous and Mesoporous Materials
Calorimetry of Immersion in the Energetic Characterization of Porous Solids
In order to study and understand the adsorption process in a liquid-solid interface, it is necessary to know both textural and chemical properties of the adsorbent. It is also important to know the behavior of the solid in a liquid medium, considering that the interaction can produce some changes in the texture and the electrochemical properties when the adsorbent is immersed in a solvent or a solution. The study of the influence of these properties in the adsorption process with techniques like immersion microcalorimetry can provide direct information on particular liquid–solid interactions. The parameter that is evaluated by immersion microcalorimetry is the immersion enthalpy, ΔHim. Immersion enthalpy is defined as the energy change at temperature and pressure constants when the surface of the solid is completely immersed in a wetting liquid in which the solid is insoluble and does not react. The immersion calorimetry can be a versatile, sensitive and precise technique that has many advantages for the characterization of porous solids. The versatility of immersion microcalorimetry is because changes in surface area, surface chemistry, or microporosity will result in a change in immersion energy. The interactions solid-liquid can be physical or chemical type, the physical present a lower amount of energy than that generated when exist chemical interactions.
Part of the book: Calorimetry