ADSORPTION SITES FOR BENZENE IN KL ZEOLITE - AN INFRARED STUDY OF MOLECULAR RECOGNITION

The adsorption of benzene is followed by infrared spectroscopy. A deta iled study in the range p/p(0) from 0 to 10(-4) is extended further to p/p(0) = 0.5. It shows that about two molecules of benzene per unit c ell strongly interact with cations for p/p(0) = 10(-4). At higher benz ene loadings the excess of aromatic is simply filling the pores. No si gnificant interaction is detected with the 12R windows. The comparison with KY, NaY, NaEMT, and NaBeta suggests that in KL a molecular recog nition effect directs the adsorption on the cations and keeps it from the 12R aperture.