Unusual phase behavior of decane–dodecane mixtures confined in SBA-15: Size effect on binary phase diagram

Phase behavior of normal decane–dodecane (n-C10H22–C12H26, C10–C12) system confined in SBA-15 (Santa Barbara Amorphous, pore diameters 3.8, 7.8, and 17.2 nm) has been studied by using differential scanning calorimetry. It has been found solid–liquid phase diagram of the C10–C12/SBA-15 system is composed of a straight line (3.8 nm), a curve (7.8 nm) and a loop line (17.2 nm). The growth of the phase diagram clearly shows the size effect on phase behavior of binary alkanes. Phase behavior has been compared among the systems C10H22–C12H26/SBA-15, C12H26–C14H30/SBA-15 and C14H30–C16H34/SBA-15.