@article {97,
	title = {Water adsorption constrained Frenkel-Halsey-Hill adsorption activation theory: Montmorillonite and illite.},
	journal = {Atmospheric Environment},
	volume = {87},
	year = {2014},
	note = {CAPLUS AN 2014:435046(Journal; Online Computer File)},
	pages = {26 - 33},
	publisher = {Elsevier Ltd.},
	abstract = {Fresh mineral aerosol has recently been found to be effective cloud condensation nuclei (CCN) and contribute to the no. of cloud droplets in the atm. due to the effect of water adsorption on CCN activation.  The work described here uses exptl. water adsorption measurements on Na-montmorillonite and illite clay to det. empirical adsorption parameters that can be used in a recently derived theor. framework (Frenkel-Halsey-Hill Activation Theory, FHH-AT) that accounts for the effect of water adsorption on CCN activation.  Upon fitting the Frenkel-Halsey-Hill (FHH) adsorption model to water adsorption measurements, we find FHH adsorption parameters, A and B, to be 98 {\textpm} 22 and 1.79 {\textpm} 0.11 for montmorillonite and 75 {\textpm} 17 and 1.77 {\textpm} 0.11 for illite, resp.  The A and B values obtained from water adsorption measurements differ from values reported previously detd. by applying FHH-AT to CCN activation measurements.  Differences in FHH adsorption parameters were attributed to different methods used to obtain them and the hydratable nature of the clays.  FHH adsorption parameters detd. from water adsorption measurements were then used to calc. the crit. super-satn. (s) for CCN activation using FHH-AT.  The relationship between s and the dry particle diam. (D) gave CCN activation curve exponents (x) of -0.61 and -0.64 for montmorillonite and illite, resp.  The x values were slightly lower than reported previously for mineral aerosol.  The lower exponent suggests that the CCN activity of hydratable clays is less sensitive to changes in D and the hygroscopicity parameter exhibits a broader variability with D compared to more sol. aerosols.  Despite the differences in A, B and x, the FHH-AT derived CCN activities of montmorillonite and illite are quite similar to each other and in excellent agreement with exptl. CCN measurements resulting from wet-generated clay aerosol.  This study illustrates that FHH-AT using adsorption parameters constrained by water adsorption is a simple, valid method for predicting CCN activation of fresh clay minerals and provides parameters that can be used in atm. models to study the effect of mineral dust aerosol on cloud formation and climate. [on SciFinder(R)]},
	keywords = {dust montmorillonite illite water adsorption activation cloud condensation nuclei},
	isbn = {1352-2310},
	author = {Hatch, Courtney D. and Greenaway, Ann L. and Christie, Matthew J. and Baltrusaitis, Jonas.}
}
@article {148,
	title = {Water Adsorption on Clay Minerals As a Function of Relative Humidity: Application of BET and Freundlich Adsorption Models.},
	journal = {Langmuir},
	volume = {28},
	year = {2012},
	note = {CAPLUS AN 2011:1640459(Journal; Online Computer File)},
	month = {2012///},
	pages = {1790 - 1803},
	publisher = {American Chemical Society},
	abstract = {Water adsorption on kaolinite, illite, and montmorillonite clays was studied as a function of relative humidity (RH) at room temp. (298 K) using horizontal attenuated total reflectance (HATR) FTIR spectroscopy equipped with a flow cell.  The water content as a function of RH was modeled using the Brunauer, Emmett, and Teller (BET) and Freundlich adsorption isotherm models to provide complementary multilayer adsorption anal. of water uptake on the clays.  A detailed anal. of model fit integrity is reported.  From the BET fit to the exptl. data, the water content on each of the three clays at monolayer (ML) water coverage was detd. and found to agree with previously reported gravimetric data.  However, BET anal. failed to adequately describe adsorption phenomena at RH values >80\%, 50\%, and 70\% RH for kaolinite, illite, and montmorillonite clays, resp.  The Freundlich adsorption model was found to fit the data well over the entire range of RH values studied and revealed two distinct water adsorption regimes.  Data obtained from the Freundlich model showed that montmorillonite has the highest water adsorption strength and highest adsorption capacity at RH values >19\% (i.e., above ML water adsorption) relative to the kaolinite and illite clays.  The difference in the obsd. water adsorption behavior between the three clays was attributed to different water uptake mechanisms based on a distribution of available adsorption sites.  Probably different properties drive water adsorption under different adsorption regimes resulting in the broad variability of water uptake mechanisms. [on SciFinder(R)]},
	keywords = {water adsorption clay mineral humidity},
	isbn = {0743-7463},
	author = {Hatch, Courtney D. and Wiese, Jadon S. and Crane, Cameron C. and Harris, Kenneth J. and Kloss, Hannah G. and Baltrusaitis, Jonas.}
}
