CONFIGURATIONAL-BIAS MONTE-CARLO (CB-MC) CALCULATIONS OF N-ALKANE SORPTION IN ZEOLITE-RHO AND ZEOLITE-FER

A newly-developed Monte Carlo method is used to simulate the energetic s, location and conformation of n-alkanes from butane to decane inside all-silica polymorphs of zeolites rho and ferrierite. Sorption in fer rierite yields far larger heats of adsorption than in rho. In rho, the alkanes adopt highly coiled conformations within the alpha-cages of t he structure, whereas in ferrierite they are confined to all-trans con formations within the 10-ring channel. Only butane is distributed over both the 8-ring and 10-ring channels of ferrierite in the approximate ratio of 1:2. An increase in temperature to 498 K has little effect o n the heats of adsorption, locations or conformations of the alkanes.