TY  - INPR
JF  - ACS Omega
Y1  - 2024/03/27/
N1  - © 2024 The Authors. Published by American Chemical Society. This publication is licensed under

CC-BY 4.0.
ID  - discovery10189981
PB  - American Chemical Society (ACS)
TI  - Modeled versus Experimental Salt Mixture Behavior under Variable Humidity
AV  - public
N2  - This study investigates the kinetics of salt mixture crystallization under relative humidity (RH) conditions, varying between 15 and 95% (at 20 °C), to inform applications in built heritage preservation, geology, and environmental sciences. We focused on commonly found, sulfate-rich and calcium-rich salt mixtures containing five to six ions, Cl?, NO3?, Na+, and K+, including or excluding less common Mg2+, and including either an excess of SO42? or Ca2+, with respect to gypsum. Using time-lapse micrographs and dynamic vapor sorption, we explore how crystallization and dissolution behavior depend on RH and mixture composition under constant temperature. A range of RH change rates were studied to simulate realistic weather events. Microstructural analyses through environmental scanning electron microscopy (ESEM) confirmed the crystal habit corresponding with RH transitions. Phases predicted from thermodynamic modeling (ECOS/RUNSALT) were confirmed using micro-Raman spectroscopy, X-ray diffraction (XRD), and elemental mapping via energy-dispersive X-ray spectroscopy (EDX). We identify a strong correlation between phase transition kinetics and RH change rates, with crystallization deviating by ?15% and dissolution by +7% from modeled values under rapid (several seconds) and slow (several days) RH changes. These insights are important for preservation strategies in built heritage, salt deposition, and dissolution mechanisms in diverse geological and realistic environmental contexts, laboratory experiments, future modeling efforts, and the understanding of stone decay in general.
KW  - Crystallization
KW  -  Dissolution
KW  -  Mixtures
KW  -  Salts
KW  -  Vinyl
UR  - http://dx.doi.org/10.1021/acsomega.4c01486
A1  - Godts, Sebastiaan
A1  - Steiger, Michael
A1  - Stahlbuhk, Amelie
A1  - Orr, Scott Allan
A1  - Desarnaud, Julie
A1  - De Clercq, Hilde
A1  - Cnudde, Veerle
A1  - De Kock, Tim
SN  - 2470-1343
ER  -