CAPILLARY CONDENSATION OF A FLUID IN A SLIT-LIKE PORE FILLED WITH OBSTACLES: LATTICE MONTE CARLO SIMULATION

We study the capillary condensation of a lattice gas with nearest neighbor attraction confined to a slit-like pore filled with frozen obstacles (matrix). First, the lattice Monte Carlo simulations were performed for a slit-like pore without obstacles. Next, the pore filled with obstacles, i.e., confined microporous medium, is prepared by adsorbing and then by quenching a hard sphere fluid in the pore of the width H. The model includes fluid-wall attraction; however, the fluid-matrix interaction is entirely repulsive. We have investigated how concentration of obstacles and the pore width H influence the capillary phase diagrams. Our numerical experiments reveal essential changes in the critical temperature and in the shape of the coexistence line with the amount of quenched obstacles.