TY - JOUR
T1 - Self-Generated Electrokinetic Fluid Flows during Pseudomorphic Mineral Replacement Reactions
AU - Kar, Abhishek
AU - McEldrew, Michael
AU - Stout, Robert F.
AU - Mays, Benjamin E.
AU - Khair, Aditya
AU - Velegol, Darrell
AU - Gorski, Christopher A.
N1 - Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/5/31
Y1 - 2016/5/31
N2 - Pseudomorphic mineral replacement reactions involve one mineral phase replacing another, while preserving the original mineral's size and texture. Macroscopically, these transformations are driven by system-wide equilibration through dissolution and precipitation reactions. It is unclear, however, how replacement occurs on the molecular scale and what role dissolved ion transport plays. Here, we develop a new quantitative framework to explain the pseudomorphic replacement of KBr crystal in a saturated KCl solution through a combination of microscopic, spectroscopic, and modeling techniques. Our observations reveal that pseudomorphic mineral replacement (pMRR) is transport-controlled for this system and that convective fluid flows, caused by diffusioosmosis, play a key role in the ion transport process across the reaction-induced pores in the product phase. Our findings have important implications for understanding mineral transformations in natural environments and suggest that replacement could be exploited in commercial and laboratory applications.
AB - Pseudomorphic mineral replacement reactions involve one mineral phase replacing another, while preserving the original mineral's size and texture. Macroscopically, these transformations are driven by system-wide equilibration through dissolution and precipitation reactions. It is unclear, however, how replacement occurs on the molecular scale and what role dissolved ion transport plays. Here, we develop a new quantitative framework to explain the pseudomorphic replacement of KBr crystal in a saturated KCl solution through a combination of microscopic, spectroscopic, and modeling techniques. Our observations reveal that pseudomorphic mineral replacement (pMRR) is transport-controlled for this system and that convective fluid flows, caused by diffusioosmosis, play a key role in the ion transport process across the reaction-induced pores in the product phase. Our findings have important implications for understanding mineral transformations in natural environments and suggest that replacement could be exploited in commercial and laboratory applications.
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U2 - 10.1021/acs.langmuir.6b00462
DO - 10.1021/acs.langmuir.6b00462
M3 - Article
AN - SCOPUS:84973281904
SN - 0743-7463
VL - 32
SP - 5233
EP - 5240
JO - Langmuir
JF - Langmuir
IS - 21
ER -