(320u) Adsorption of Mixed Organic Solvent by Y Type Zeolite

In recent years, instead of the chlorofluorocarbon specified as the ozone-depleting substance, a chlorinated organic compound, hydrocarbon, alcohol, etc. are used as an alternative washing solvent, and they are used as a mixed solvent in many cases. Therefore, adsorption operation of binary systems is needed. Furthermore, since azeotropic may happen, in the case of the design of a solvent recovery system and operation, those adsorption equilibrium are required as basic data. This study considered the adsorption equilibrium relation used as basic data required in order to adsorb various binary mixture solvent vapor by high silica zeolite (HSZ). Moreover, the breakthrough simulation using the STOP & GO method was performed and compared with the experiment result. The adsorbate used were ethanol and trichloroethylene which are the system of azeotropic mixture. The Experiments were carried out using a flow method, changing the total concentration of ethanol and trichloroethylene and composition. By this system, one azeotropic point appeared and three kinds of breakthrough curves were obtained by the difference in composition. The adsorption and desorption experiments were repeated. Degradation by using Y type high silica zeolite repeatedly was seldom seen. Repeated adsorption runs were reproducible. And it can be said that this azeotropic adsorption is reversible phenomenon. The STOP & GO method is a simulation which considers that each column is divided to N complete mixed cells, and the adsorbed or desorbed amount of the adsorbate within this time interval and the flows between cells are calculated repeatedly. The azeotropic theory in a liquid-vapor azeotropic equilibrium was used for this binary system instead of Langmuir equation. Breakthrough curve could be simulated using the Stop & Go method in the whole range for azeotropic mixture systems as well as for zeotropic systems.