Two experimental methods to study adsorption equilibria of xylene isomers in the liquid phase on a Y zeolite

Two experimental complementary techniques for the study of the adsorption o f a binary liquid mixture p-xylene/m-xylene on a dehydrated KBaY zeolite at 50 degrees C are described in this paper: (1) a classical method using a g as chromatograph (GC) allowed us to measure selectivities in the concentrat ion range [3%, 95%] p-xylene; (2) an original method using a GC-combustion (C)-isotopic ratio mass spectrometer (IRMS) and C-13 labeled xylenes was de veloped to investigate the ranges of strongly contrasting concentrations [0 %, 3%] and [95%, 100%] p-xylene, which ate representative of high purity do mains. Both techniques are based on the use of an inert component to perfor m mass balance calculations and analyses of the liquid phase after adsorpti on. Comparison tests were carried out between the two techniques, and the r esults are satisfactory. Lastly, the Langmuir-Freundlich model yielded a go od representation of our adsorption data. (C) 2000 Elsevier Science B.V. Al l rights reserved.