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 for the first time applied to study a heterogeneously catalyzed reaction. A temperature jump from 20 to 100-150 degrees C creates a nonequilibrium stale of the system consisting of methyl tert-butyl ether (MTBE), methanol, and isobutene, which are adsorbed on a boron pentasil zeolite in a sealed glass tube, The rate constants of MTBE decomposition and 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 reactor or in an autoclave.