Thermodynamic properties of the lithium bromide + diethanolamine + water system

Abstract

Thermodynamic properties (solubility, vapor pressure, density, viscosity, and heat capacity) of the lithium bromide + diethanolamine + water system (LiBr/(HOCH2CH2)2NH, mass ratio = 3.5) were measured as a possible new working fluid for absorption heat pumps. Solubility was measured by the visual polythermal method in the temperature range from 281.75 to 338.95 K and vapor pressure by the boiling point method from 329.15 to 401.25 K. Density and viscosity were measured by using a set of hydrometers and five pieces of Ubbelohde-type capillary viscometers in the temperature range from 283.15 to 343.15 K. Heat capacity was measured by using an isoperibol solution calorimeter in the temperature range from 283.15 to 333.15 K. Each measured data set was correlated with a proper equation, and all the correlation results showed good agreement between measured and calculated values.