0000000001225741
AUTHOR
A. Mokhlisse
Absorption and desorption of liquid water by a superabsorbent polymer: Effect of polymer in the drying of the soil and the quality of certain plants
In this work, we were interested in the study of the kinetic behavior of the reaction of drying soil representing the Marrakesh region (south of Morocco) in the presence of an superabsorbent polymer. The presence of a polymer in the soil diminished the kinetic drying of the soil, which will have as an application a reduction in water loss in the process of irrigation. The presence of a polymer in the soil enables a complete modification of the kinetic regimes controlling the soil-drying kinetic. We also realized the first study of the behavior of certain selected plants in the melange of a soil and a polymer. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 234–243, 2002
Absorption et désorption de l’eau liquide par un polymère superabsorbant
Resume L’etude cinetique du sechage d’un gel (polymere mouille) a montre que les reactions de sechage effectuees sous pression reduite de vapeur d’eau sont generalement rapides meme a basse temperature, ce qui est un avantage par rapport aux systemes zeolithiques. En effet, les systemes zeolithiques presentent une cinetique de regeneration lente ce qui peut limiter leurs utilisation dans le domaine des energies renouvelables et en particulier celui des pompes a chaleur chimique. L’utilisation des masses elevees du gel permet de modifier completement le regime cinetique limitant la reaction de sechage; il passe en chauffage classique d’un phenomene controle par l’evaporation suivie d’une dif…
Absorption and desorption of liquid water by a superabsorbent polyelectrolyte: Role of polymer on the capacity for absorption of a ground
To study the potentialities of a polyelectrolyte superabsorbent for the storage of water, we have studied a ground representative of the area of Haouz (area of Marrakesh, South of Morocco) in the presence of polymer. We sought the optimal proportions allowing the best retention of water by the mixture made up of the polymer and the ground and to prolong the storage period of water in the ground. We have also studied the effect of certain ions and the pH on the capacity for absorption of polymer. These ions can be naturally present in the ground or introduced by the means of manure and pesticides. The presence of polymer in the ground makes it possible to increase the capacity for absorption…
Étude thermodynamique du polymère super absorbant X10 vis–à–vis de l’eau vapeur
The organic polymers super absorbents present values of specific surface lower than 2m 2 /g. The isobars of adsorption of water vapor on studied polymer are of type III at ambient temperature with the hysterisis phenomena.For temperatures lower than ambient, the isobars become deformed because of an effect of chains. This type of polymer is characterized by a multi-layer adsorption which occurs before the full-course one is complete. During reactions of adsorption, the polymer undergoes rearrangement polymeric network which results from a co-operative diffusion of the water molecules and from a spacing of chain followed by an expansion of the polymeric network. Three types of water molecule…
The adsorption of water vapor on super absorbent product at low temperatures and low mass.
The adsorption isotherms of water vapor on super absorbent product have the same form of type III isotherm at ambient temperature with the hysteresis phenomena. For temperatures lower than ambient, the isotherms become deformed because of the chains effect. The polymer is characterized by a multilayer adsorption, which occurs before a full-course is complete. During adsorption reactions, the polymer undergoes rearrangement polymeric network, which results from a cooperative diffusion of the water molecules and from a chain spacing followed by an expansion of the polymeric network. Three types of water molecules adsorbed on polymer were identified: strongly dependent water, adsorbed water, a…
Caractéristiques des réactions endothermiques d'interface
The knowledge of the different thermodynamic states of an evaporative interface leads us to propose a formulation of the evolution laws (evaporation rate vs pressure) adapted to each regime (interfacial equilibrium or non equilibrium). Starting from fluid dynamics and irreversible thermodynamics, the model is able to determine the interface flux-forces relations which express the transport coefficients and the thermodynamic coupling effects. The theoretical results are compared to experimental data relative to water evaporation al T =313 K. Taking into account the different regimes arising for the deviation from equilibrium, the model reproduces quantitatively the experimental kinetic curve…
Caractéristiques des réactions endothermiques d'interface. Recherche des états thermodynamiques d'interface en relation avec les écarts à l'équilibre t. 292, pp. 49 52.
International audience; L'endothermicité de la vaporisation peut donner des propriétés particulières à l'interface. L'exploration de la carte thermique du système associée à un modèle permet d'accéder aux profils thermiques dans chaque phase et d'établir les températures à l'interface; ses différents états thermodynamiques sont en relation avec l'écart à l'équilibre du système : équilibre interfacial près de l'équilibre, puis apparition d'une discontinuité de température, enfin déséquilibre de température et de potentiel chimique.