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We report experimental results forthe melting of eutectic mixturesconfined in nanoporous matrices. Dielectric relaxation spectroscopyand differential scanning calorimetry were used to determine the solid/liquidphase diagram of C6H4Br2/CCl4mixtures confined in controlled pore glasses (CPG) with anaverage pore diameter of 7.5 nm, and C6H5Br/CCl4mixtures confined in activated carbon fibers (ACF) with amean pore diameter of 1.4 nm. We find that the phase diagram of theconfined mixtures are of the same type as that for the bulk mixture(eutectic). However, in the case of mixtures in carbon nanopores thesolid/liquid coexistence lines are located at higher temperaturesthan for the bulk mixtures, whereas they are at lower temperaturesthan the bulk for mixtures confined in silica pores. These resultsare compared with those previously obtained for azeotropic mixturesin ACF. The results suggest that the melting temperatures, Tmp, of confined mixtures decrease relative tothe bulk when the fluid–wall interactions are weaker than thefluid–fluid interaction (silica glasses), and increase in thecase of fluid–wall interactions that are stronger than thefluid–fluid interaction (nanoporous carbons). [ABSTRACT FROM AUTHOR]