USE OF ~1H NMR IMAGING TO STUDY COMPETITIVE ADSORPTION OF HYDROCARBONS IN ZEOLITES

摘要

~1H NMR imaging has been used to study the adsorption or desorption of pure or mixed hydrocarbons (benzene, n-hexane,) on or from a fixed bed of HZSM-5 zeolite crystallites. This technique makes it possible to visualise the progression of the diffusing molecules in the bed of the catalyst and to determine their intracrystallite diffusion coefficient. In the case of competitive adsorption, it gives the instantaneous distribution of the two components before thermodynamic equilibrium is reached.