论文信息 - Heat capacities of concentrated aqueous alkaline aluminate solutions at 25°C

Heat capacities of concentrated aqueous alkaline aluminate solutions at 25°C

Heat capacities of aqueous NaOH/NaAl(OH)4 solutions at total stoichiometric ionic strengths of up to 6 mol kg-1 and with up to 60 mol % substitution of OH- by Al(OH)4- have been measured at 25 °C using a Picker flow calorimeter. The mean apparent molar heat capacities (Cpφ) of the NaOH/NaAl(OH)4 mixtures were linear with respect to Al(OH)4- substitution, consistent with Young's rule. This enabled Cpφvalues to be derived for the hypothetical pure NaAl(OH)4(aq) solutions. The results so obtained are well described by a Pitzer model adapted from the literature, even up to high concentrations.

E. Königsberger | G. Hefter | M. Magalhães | A. May

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