Crystallization of carbon tetrachloride in confined geometries

Adil Meziane, Jean-Pierre E. Grolier, Mohamed Baba, Jean-Marie Nedelec
2007 Faraday discussions  
Phone 00 33 (0)4 73 40 71 95 Fax 00 33 (0)4 73 40 71 08 Abstract The thermal behaviour of carbon tetrachloride confined in silica gels of different porosity was studied by differential Scanning Calorimetry. Both the melting and the phase transition at low temperature were measured and found to be inextricably dependant upon the degree of confinement. The amount of solvent was varied through two sets of experiments, sequential addition and original progressive evaporation allowing the
more » ... wing the measurement of the DSC signals for the various transitions as a function of the amount of CCl 4 . These experiments allowed the determination of transition enthalpies in the confined state which in turn allowed the determination of the exact quantities of solvent undergoing the transitions. A clear correlation was found between the amounts of solvent undergoing the two transitions (both free and confined) demonstrating that the formation of the adsorbed layer t does not interfere with the second transition. The thickness of this layer and the porous volumes of the two silica samples were measured and found to be in very close agreement with the values determined by gas sorption.
doi:10.1039/b616128f pmid:17955822 fatcat:u3o5ubaynza3vdshhyem7saxtm