On the explanation of hysteresis in the adsorption of ammonia on graphitized thermal carbon black

摘要: We present a Monte Carlo simulation and experimental study of ammonia adsorption on graphitized thermal carbon black. Our new molecular model for the adsorbent is composed basal plane graphene surfaces with ultrafine pores grafted hydroxyl groups at junctions between layers. The simulated isotherms isosteric heats are in good agreement data Holmes Beebe, simulations reproduce unusual hysteresis an open graphite surface first time literature. detailed mechanisms desorption, origin hysteresis, investigated by microscopic analysis adsorbate structures to show that restructuring occurs during adsorption. main results from this work are: (i) triple point, adsorbs preferentially around functional form clusters spills-over onto as loading increased; followed 2D condensation bilayer adsorbate; (ii) boiling due increasing importance fluctuations (an entropic effect); (iii) heat very high zero strong interaction groups, decreases steeply when group saturated, eventually reaches fluid-fluid increases.