eprintid: 10189981
rev_number: 7
eprint_status: archive
userid: 699
dir: disk0/10/18/99/81
datestamp: 2024-04-05 12:59:16
lastmod: 2024-04-05 12:59:16
status_changed: 2024-04-05 12:59:16
type: article
metadata_visibility: show
sword_depositor: 699
creators_name: Godts, Sebastiaan
creators_name: Steiger, Michael
creators_name: Stahlbuhk, Amelie
creators_name: Orr, Scott Allan
creators_name: Desarnaud, Julie
creators_name: De Clercq, Hilde
creators_name: Cnudde, Veerle
creators_name: De Kock, Tim
title: Modeled versus Experimental Salt Mixture Behavior under Variable Humidity
ispublished: inpress
divisions: UCL
divisions: B04
divisions: C04
divisions: F34
keywords: Crystallization, Dissolution, Mixtures, Salts, Vinyl
note: © 2024 The Authors. Published by American Chemical Society. This publication is licensed under

CC-BY 4.0.
abstract: 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.
date: 2024-03-27
date_type: published
publisher: American Chemical Society (ACS)
official_url: http://dx.doi.org/10.1021/acsomega.4c01486
oa_status: green
full_text_type: pub
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 2263395
doi: 10.1021/acsomega.4c01486
lyricists_name: Orr, Scott
lyricists_id: SAORR49
actors_name: Orr, Scott
actors_id: SAORR49
actors_role: owner
full_text_status: public
publication: ACS Omega
issn: 2470-1343
citation:        Godts, Sebastiaan;    Steiger, Michael;    Stahlbuhk, Amelie;    Orr, Scott Allan;    Desarnaud, Julie;    De Clercq, Hilde;    Cnudde, Veerle;           Godts, Sebastiaan;  Steiger, Michael;  Stahlbuhk, Amelie;  Orr, Scott Allan;  Desarnaud, Julie;  De Clercq, Hilde;  Cnudde, Veerle;  De Kock, Tim;   - view fewer <#>    (2024)    Modeled versus Experimental Salt Mixture Behavior under Variable Humidity.                   ACS Omega        10.1021/acsomega.4c01486 <https://doi.org/10.1021/acsomega.4c01486>.    (In press).    Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10189981/1/godts-et-al-2024-modeled-versus-experimental-salt-mixture-behavior-under-variable-humidity.pdf