Does Langmuir model predict evaporation rates?

[Slide #16 of this presentation on amalgams](https://www.fda.gov/ohrms/dockets/ac/06/slides/2006-4218s1-03.pdf) says that "Langmuir's equation" provides a specific "theoretical maximum evaporation rate" for liquid Hg as a function of temperature and surface area.


The only common equation bearing Langmuir's name is [his adsorption model](https://en.wikipedia.org/wiki/Langmuir_adsorption_model). I can vaguely imagine that model being applied in reverse to characterize evaporation rates, but I can't see or find how in general, much less in the specific case asserted in the paper. Can someone provide a reference or example of how that (or any other model) provides a "theoretical maximum evaporation rate" of a particular liquid?




That most likely refers to the [Hertz-Knudsen equation](https://en.wikipedia.org/wiki/Hertz%E2%80%93Knudsen_equation), also known as **Knudsen-Langmuir equation**. It is the most simplified model of evaporation in which no discussion is given into the diffusivity and the chemical potential gradient (let alone other driving forces like gravity and pressure gradient): one just assumes the leaving mass flux is dictated by the system's thermal energy. This model then suggests a direct relation between evaporation rate and vapor pressure, temperature and molar mass.


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