Dynamics of water and methanol in H-mordenite

The dynamic behaviors of water and methanol in acidic mordenite are studied using a novel quantum chemical molecular dynamics program and density functional method. The calculated adsorption energies for methanol and water are -108.3 and -95.2 kJ/mol, respectively. Although cationic species viz., H ₃O⁺ and CH₃OH₂⁺ were found to be more stable than neutral species by DF method, molecular dynamics simulations at finite temperatures revealed that cationic species are only short-time living species. Increasing the loading ratio of methanol to two molecules per one acidic site decreases the adsorption energy to -87.6 kJ/mol.