New “batch” cells adapted to measure saturated heat capacities with a Micro DSC II (Setaram) microcalorimeter designed to avoid any leakage during measurement are described. Using the “scanning” and “step-by-step” methods, the heat capacities of pure organic liquidshexane, heptane, decane, dodecane, cyclohexane, toluene, methanol, and 1-butanolin the temperature range (5 to 75) °C were determined. In addition, the excess heat capacities of several binary liquid mixtures(benzene + cyclohexane) and (2,5,8,11-tetraoxadodecane + dodecane)with the step-by-step procedure were measured. A very close agreement with literature values better than 1% indicates that the apparatus and technique are suitable for heat capacity measurements on volatile liquids.

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The saturated heat capacities of some linear alkylbenzenes (ethylbenzene, propylbenzene, butylbenzene, hexylbenzene, 1-phenylheptane, and 1-phenylhexadecane) and branched alkylbenzenes (m-xylene, cumene, (1-methylpropyl)benzene, (1,1-dimethylethyl)benzene, and (2-methylpropyl)benzene) in the temperature range from (332.15 to 401.15) K have been measured. A Calvet calorimeter C80D from Setaram (France) with batch cells modified from the standard vessels of Setaram, along with the "step by step method", has been used to perform the measurements. The estimated uncertainty of the saturated heat capacities was better than 0.5 % for the substances with higher purity and of the order of 1 % for the others. In the literature there exists c sat (T) data for some of the liquids studied. Agreement with our measurements is within the range of the experimental uncertainties.

The saturated heat capacities of oxygenated gasoline additives methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), diisopropyl ether (DIPE), and tert-amyl methyl ether (TAME) in the temperature range of 277.15 K to some degrees below their normal boiling temperatures have been measured. A Micro DSC II from Setaram (France) with batch cells designed in our laboratory and the "scanning method" were used to perform the measurements. The estimated uncertainty of the saturated heat capacities was better than 0.3%. In the literature, there exist c sat (T) data for some of the liquids studied. Agreement with our measurements is within the range of the experimental uncertainties. At each temperature, the saturated heat capacity of liquid MTBE is smaller than those of ETBE, DIPE, and TAME, and the corresponding c sat values of these three liquids are similar. This behavior can be related with the surface fraction of the ether group in each molecule.