TY - JOUR

T1 - Comparative study of the HP-HT behavior of a layered silicate apophyllite in water and paraffin oil

AU - Likhacheva, Anna Yu

AU - Goryainov, Sergey V.

AU - Ignatov, Mark A.

AU - Romanenko, Alexandr V.

AU - Seryotkin, Yurii V.

N1 - Funding Information: We thank G.D. Gatta and the anonymous reviewers for their comprehensive remarks, as well as I.A. Belitsky for providing us with the apophyllite sample. The chemical analysis of apophyllite was carried out with the use of analytical equipment of the Analytical Center for multi‐elemental and isotope research SB RAS (Novosibirsk, Russia). The study was supported by grant 22‐27‐00235 from the Russian Science Foundation. Publisher Copyright: © 2022 John Wiley & Sons Ltd.

PY - 2023/2

Y1 - 2023/2

N2 - The interaction of porous minerals with liquids, especially water, is involved in many technological and geochemical processes. Apophyllite (K,Na)Ca4[Si8O20](F,OH).8H2O, exhibiting mixed properties of layered and framework microporous silicates, is a promising object to model the interaction of a fluid with porous material. It was studied by the in situ Raman spectroscopy at simultaneously high pressure (HP) and high temperature (HT) up to 225°C and 9 GPa in order to clarify the effect of the composition of the pressure medium and the temperature on its HP behavior. Penetrating (water) and nonpenetrating (paraffin oil) media were used. Independently of the compressing medium, at HT, the lattice vibrational modes of apophyllite demonstrate regular pressure shifts. Almost uniform shift rates imply little differentiation between the compression of silicate layers and interlayer ion-molecular assemblage. Similar HP behavior of apophyllite in penetrating and nonpenetrating media indicates no pressure-induced overhydration within 1–9 GPa. Thereby, the significance of such structural factors, as a limited H2O mobility and relatively strong contacts between silicate layers, determining low structure tolerance towards the penetration of additional molecules, is emphasized. The elevated temperature does not affect the mobility of the interlayer H2O molecules to allow the pressure-induced intercalation in apophyllite.

AB - The interaction of porous minerals with liquids, especially water, is involved in many technological and geochemical processes. Apophyllite (K,Na)Ca4[Si8O20](F,OH).8H2O, exhibiting mixed properties of layered and framework microporous silicates, is a promising object to model the interaction of a fluid with porous material. It was studied by the in situ Raman spectroscopy at simultaneously high pressure (HP) and high temperature (HT) up to 225°C and 9 GPa in order to clarify the effect of the composition of the pressure medium and the temperature on its HP behavior. Penetrating (water) and nonpenetrating (paraffin oil) media were used. Independently of the compressing medium, at HT, the lattice vibrational modes of apophyllite demonstrate regular pressure shifts. Almost uniform shift rates imply little differentiation between the compression of silicate layers and interlayer ion-molecular assemblage. Similar HP behavior of apophyllite in penetrating and nonpenetrating media indicates no pressure-induced overhydration within 1–9 GPa. Thereby, the significance of such structural factors, as a limited H2O mobility and relatively strong contacts between silicate layers, determining low structure tolerance towards the penetration of additional molecules, is emphasized. The elevated temperature does not affect the mobility of the interlayer H2O molecules to allow the pressure-induced intercalation in apophyllite.

KW - high pressure

KW - high temperature

KW - layer silicate

KW - paraffin oil

KW - water

UR - http://www.scopus.com/inward/record.url?scp=85142350371&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/66d8ff8c-4f93-3359-adf8-702b29ff2390/

U2 - 10.1002/jrs.6468

DO - 10.1002/jrs.6468

M3 - Article

AN - SCOPUS:85142350371

VL - 54

SP - 209

EP - 216

JO - Journal of Raman Spectroscopy

JF - Journal of Raman Spectroscopy

SN - 0377-0486

IS - 2

ER -