Thermodynamics of vivianite-group arsenates M3(AsO4)2.8H2O (M is Ni, Co, Mg, Zn, Cu) and chemical variability in the natural arsenates of this group

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00023272%3A_____%2F24%3A10136227" target="_blank" >RIV/00023272:_____/24:10136227 - isvavai.cz</a>

Výsledek na webu

<a href="https://ejm.copernicus.org/articles/36/31/2024/" target="_blank" >https://ejm.copernicus.org/articles/36/31/2024/</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.5194/ejm-36-31-2024" target="_blank" >10.5194/ejm-36-31-2024</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Thermodynamics of vivianite-group arsenates M3(AsO4)2.8H2O (M is Ni, Co, Mg, Zn, Cu) and chemical variability in the natural arsenates of this group

Popis výsledku v původním jazyce

In this work, we investigated the M3(AsO4)2.8H2O end members annabergite (M = Ni), erythrite (M = Co), hornesite (M = Mg), and their solid solutions. Acid-solution calorimetry and relaxation calorimetry were used to determine the solubility products (logKsp) for annabergite (MINUS SIGN 33.7), erythrite (MINUS SIGN 32.1), and hornesite (MINUS SIGN 22.3). Solubility products for other end members of this group were extracted from literature and critically evaluated. The enthalpies of mixing are complex, related to subsystems M(1)3(AsO4)2.8H2O - M(1)M(2)2(AsO4)2.8H2O and M(1)M(2)2(AsO4)2.8H2O - M(2)3(AsO4)2.8H2O. They are small and positive for the annabergite-erythrite solid solution and small and negative for the annabergite-hornesite solid solution. Autocorrelation analysis of FTIR spectra shows correlation of strain decrease in the structure with the negative enthalpies of mixing in the annabergite-hornesite solid solution. A set of more than 600 electron microprobe analyses of the M3(AsO4)2.8H2O minerals documents the variability and complexity in this group. Most common compositions are those dominated by Ni, Co, or Ni-Co. The analytical results were used to calculate the maximal configurational entropies which could be a factor that compensates for the small enthalpies of mixing in the annabergite-erythrite solid solution. The data presented here can be used to model sites polluted with metals and arsenic and to enhance our understanding of complex solid solutions.

Název v anglickém jazyce

Thermodynamics of vivianite-group arsenates M3(AsO4)2.8H2O (M is Ni, Co, Mg, Zn, Cu) and chemical variability in the natural arsenates of this group

Popis výsledku anglicky

In this work, we investigated the M3(AsO4)2.8H2O end members annabergite (M = Ni), erythrite (M = Co), hornesite (M = Mg), and their solid solutions. Acid-solution calorimetry and relaxation calorimetry were used to determine the solubility products (logKsp) for annabergite (MINUS SIGN 33.7), erythrite (MINUS SIGN 32.1), and hornesite (MINUS SIGN 22.3). Solubility products for other end members of this group were extracted from literature and critically evaluated. The enthalpies of mixing are complex, related to subsystems M(1)3(AsO4)2.8H2O - M(1)M(2)2(AsO4)2.8H2O and M(1)M(2)2(AsO4)2.8H2O - M(2)3(AsO4)2.8H2O. They are small and positive for the annabergite-erythrite solid solution and small and negative for the annabergite-hornesite solid solution. Autocorrelation analysis of FTIR spectra shows correlation of strain decrease in the structure with the negative enthalpies of mixing in the annabergite-hornesite solid solution. A set of more than 600 electron microprobe analyses of the M3(AsO4)2.8H2O minerals documents the variability and complexity in this group. Most common compositions are those dominated by Ni, Co, or Ni-Co. The analytical results were used to calculate the maximal configurational entropies which could be a factor that compensates for the small enthalpies of mixing in the annabergite-erythrite solid solution. The data presented here can be used to model sites polluted with metals and arsenic and to enhance our understanding of complex solid solutions.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

10504 - Mineralogy

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

European Journal of Mineralogy

ISSN

1617-4011

e-ISSN

—

Svazek periodika

36

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

24

Strana od-do

31-54

Kód UT WoS článku

001173378300001

EID výsledku v databázi Scopus

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