Reversibility Studies of Clay Hydration Degree in its Natural and Composite Condition

Abstract

In this work, the regeneration of desiccant compounds materials was studied after of its adsorption capacity. Also, reuse of the materials was evaluated after progressive regenerations. For this, the effect of regeneration temperature on adsorption capacity of the desiccant compounds materials was analyzed. For the tests adsorption of water a certain amount of dry sample was placed in a desiccator at 98% RH and 298 K, until reach the time of equilibrium, in which the final weight was recorded. In order to check the reversibility of the process re-adsorption studies were performed with water. To do this, before starting the second adsorption cycle, the same portion of sample was dried again to release the adsorbed water, using temperatures of 343 K and 373 K. Later was proceeded similarly to first adsorption cycle. After to this procedure was reiterated 5 times the test results showed no significant decrease in the efficiency of the material when the samples were regenerated at 373 K. In this way, was possible to maintain approximately constant the hygroscopic characteristics of the material. From the results it was determined that the optimum temperature of drying for the regeneration process is to the corresponding to 373 K since at this temperature the rate of desorption of water is facilitated, which allows to adapt the material in order to initiate an new cycle, being in evidence a good behavior of the material in reversibility.