TEMPERATURE-JUMP RELAXATION MAGIC-ANGLE-SPINNING NMR-STUDY OF THE METHYL TERT-BUTYL ETHER REACTION IN A BORON PENTASIL ZEOLITE

Temperature-jump relaxation magic-angle spinning NMR experiments are f or the first time applied to study a heterogeneously catalyzed reactio n. A temperature jump from 20 to 100-150 degrees C creates a nonequili brium stale of the system consisting of methyl tert-butyl ether (MTBE) , methanol, and isobutene, which are adsorbed on a boron pentasil zeol ite in a sealed glass tube, The rate constants of MTBE decomposition a nd formation were determined, and the corresponding apparent energies of activation are 51 and 32 kJ mol(-1), respectively, The NMR findings are in agreement with experimental results obtained in a fixed bed re actor or in an autoclave.