Heat of absorption

In the Fluid Editor, you can choose to include the heat of absorption in the calculations for liquid enthalpy for liquid activity methods when Henry's solutes are present (the Use Henry's Law checkbox is selected). You use the Include Heat of Absorption in Liquid Enthalpy Calculations checkbox to include or exclude the heat of absorption in the liquid enthalpy calculations. By default, the Include Heat of Absorption in Liquid Enthalpy Calculations checkbox is selected. When you clear this checkbox, the liquid enthalpy calculations do not include the heat of absorption (Habs = 0).

When you select the Include Heat of Absorption in Liquid Enthalpy Calculations checkbox, we calculate the heat of absorption by using the following equation:

where

Hi is the Henry's constant for component i in the solvent mixture

We use the following mixing rule to calculate the heat of absorption for the liquid phase (Habs):

For the Electrolyte NRTL (eNRTL) method, we use a reference state of infinite dilution in aqueous solution. Therefore, we assume that the solvent is pure water and calculate the heat of absorption by using the following equation:

where

Hi,w is the Henry's constant for component i in pure water

We use the following mixing rule to calculate the heat of absorption for the liquid phase (Habs):