Heat Capacities of Aqueous Ternary Mixtures of 2-Amino-2-Methyl-1, 3-Propanediol + Piperazine or Lithium Bromide

Abstract

Abstract-In this work, we reported the molar heat capacities, C P , of aqueous solutions of the sterically hindered amines 2-amino-2-methyl-1, 3-propanediol (AMPD), and its aqueous ternaries containing piperazine (PZ) or lithium bromide (LiBr). Measurements were performed in the temperature range 303.15 K to 353.15 K and atmospheric pressure by heat flow differential scanning calorimetry. The excess molar heat capacities, C P E , of the binary solutions were determined, and the data were represented as function of temperature and composition using a RedlichKister-type equation. The C P of the ternary mixtures was correlated with temperature and amine concentration using the Sohnel and Novotny equation. Results showed that the calculated data agree very well with experimental C P values at average absolute deviation values of less than 0.2%. Index Terms-2-amino-2-methyl-1, 3-propanediol, molar heat capacity, redlichkister equation, sohnel and novotny equation.