Article
Licensed
Unlicensed
Requires Authentication
Natural sepiolite: Enthalpies of dehydration, dehydroxylation, and formation derived from thermochemical studies
-
Lyubov P. Ogorodova
,
Irina A. Kiseleva
Published/Copyright:
November 12, 2014
Abstract
Sepiolite is widely used in various fields due to its unique colloidal-rheological and physicochemical properties. The first experimental thermochemical study of natural sepiolite Mg8Si12O30(OH)4(H2O)4·nH2O from Akkermanovskoe field (Southern Ural, Russia) was performed utilizing the high-temperature heat-flux Tian-Calvet microcalorimeter. X-ray powder diffraction, thermal analysis, and FTIR spectroscopy methods were used to characterize sepiolite. Processes of dehydration, dehydroxylation, and various water types’ removal enthalpies were studied using thermochemical methods. The values of Ddehydr.H0(298.15 K) of adsorbed, zeolitic, and bound water calculated per 1 mol of released H2O, were as follows: 15 ± 4, 28 ± 8, and 39 ± 15 kJ/mol, respectively. The enthalpy of dehydroxylation of sepiolite was found as 145 ± 14 kJ/(mol H2O). Obtained data point at different binding strengths of water in the structure of sepiolite. The enthalpies of formation from the elements ΔH0f (298.15 K) were derived by melt solution calorimetry for sepiolite with various content of different water types: -18 773 ± 28 kJ/mol for Mg8Si12O30(OH)4(H2O)4·4H2O and -16 426 ± 21 kJ/mol for Mg8Si12O30(OH)4(H2O)4
Keywords : Sepiolite; thermochemistry; microcalorimetry; enthalpy of dehydration; enthalpy of dehydroxylation; enthalpy of formation
Received: 2013-11-13
Accepted: 2014-5-13
Published Online: 2014-11-12
Published in Print: 2014-11-1
© 2014 by Walter de Gruyter Berlin/Boston
You are currently not able to access this content.
You are currently not able to access this content.
Articles in the same Issue
- Highlights and Breakthroughs Merrillite and apatite as recorders of planetary magmatic processes
- Highlights and Breakthroughs Comparing clays from Mars and Earth: Implications for martian habitability
- Data-driven abductive discovery in mineralogy
- Thermal expansion of fluorapatite-hydroxylapatite crystalline solutions
- Synthesis and structure of carbonated barium and lead fluorapatites: Effect of cation size on A-type carbonate substitution
- Optical absorption spectroscopy study of the causes for color variations in natural Fe-bearing gahnite: Insights from iron valency and site distribution data
- Si-magnetite nano-precipitates in silician magnetite from banded iron formation: Z-contrast imaging and ab initio study
- Ordering kinetics in synthetic Mg(Al,Fe3+)2O4 spinels: Quantitative elucidation of the whole Al-Mg-Fe partitioning, rate constants, activation energies
- Experimental study of phlogopite reaction rim formation on olivine in phonolite melts: Kinetics, reaction rates, and residence times
- Etch-pit size, dissolution rate, and time in the experimental dissolution of olivine: Implications for estimating olivine lifetime at the surface of Mars
- Ferrian saponite from the Santa Monica Mountains (California, U.S.A., Earth): Characterization as an analog for clay minerals on Mars with application to Yellowknife Bay in Gale Crater
- A large spectral survey of small lunar craters: Implications for the composition of the lunar mantle
- In-situ characterization of oxalic acid breakdown at elevated P and T: Implications for organic C-O-H fluid sources in petrologic experiments
- Slawsonite-celsian-hyalophane assemblage from a picrite sill (Prague Basin, Czech Republic)
- Determining hematite content from NUV/Vis/NIR spectra: Limits of detection
- The role of water in generation of group II kimberlite magmas: Constraints from multiple saturation experiments
- Quantum mechanical modeling of hydrolysis and H2O-exchange in Mg-, Ca-, and Nisilicate clusters: Implications for dissolution mechanisms of olivine minerals
- Redox-driven exsolution of iron-titanium oxides in magnetite in Miller Range (MIL) 03346 nakhlite: Evidence for post crystallization oxidation in the nakhlite cumulate pile?
- Energetics of lanthanide-doped calcium phosphate apatite
- Thermal conductivity of molten and glassy NaAlSi3O8, CaMgSi2O6, and Mg2SiO4 by non-equilibrium molecular dynamics at elevated temperature and pressure
- Energetics of heterometal substitution in ε-Keggin [MO4Al12(OH)24(OH2)12]6/7/8+ ions
- Ab initio calculations of elastic constants of plagioclase feldspars
- Diagenetic formation of interlayer-deficient fluorophlogopite as a clay mineral in Early Cambrian phosphorite (Lesser Himalaya, India): The trioctahedral analog of illite
- Natural sepiolite: Enthalpies of dehydration, dehydroxylation, and formation derived from thermochemical studies
- A new interpretation of decomposition products of serpentine under shock compression
- model for calculating the viscosity of natural iron-bearing silicate melts over a wide range of temperatures, pressures, oxygen fugacites, and compositions
- The replacement of chalcopyrite by bornite under hydrothermal conditions
- Characterization of porosity in sulfide ore minerals: A USANS/SANS study
- Synthesis of a quenchable high-pressure form of magnetite (h-Fe3O4) with composition Fel(Fe2+0.75Mg0.26)Fe2(Fe3+ 0.70Cr0.15Al0.11Si0.04)2O4
- High-pressure elasticity of sodium majorite garnet, Na2MgSi5O12
- Armstrongite from Khan Bogdo (Mongolia): Crystal structure determination and implications for zeolite-like cation exchange properties
- Steinhardtite, a new body-centered-cubic allotropic form of aluminum from the Khatyrka CV3 carbonaceous chondrite
- New Mineral Names
- Book Review
Keywords for this article
Sepiolite;
thermochemistry;
microcalorimetry;
enthalpy of dehydration;
enthalpy of dehydroxylation;
enthalpy of formation
Articles in the same Issue
- Highlights and Breakthroughs Merrillite and apatite as recorders of planetary magmatic processes
- Highlights and Breakthroughs Comparing clays from Mars and Earth: Implications for martian habitability
- Data-driven abductive discovery in mineralogy
- Thermal expansion of fluorapatite-hydroxylapatite crystalline solutions
- Synthesis and structure of carbonated barium and lead fluorapatites: Effect of cation size on A-type carbonate substitution
- Optical absorption spectroscopy study of the causes for color variations in natural Fe-bearing gahnite: Insights from iron valency and site distribution data
- Si-magnetite nano-precipitates in silician magnetite from banded iron formation: Z-contrast imaging and ab initio study
- Ordering kinetics in synthetic Mg(Al,Fe3+)2O4 spinels: Quantitative elucidation of the whole Al-Mg-Fe partitioning, rate constants, activation energies
- Experimental study of phlogopite reaction rim formation on olivine in phonolite melts: Kinetics, reaction rates, and residence times
- Etch-pit size, dissolution rate, and time in the experimental dissolution of olivine: Implications for estimating olivine lifetime at the surface of Mars
- Ferrian saponite from the Santa Monica Mountains (California, U.S.A., Earth): Characterization as an analog for clay minerals on Mars with application to Yellowknife Bay in Gale Crater
- A large spectral survey of small lunar craters: Implications for the composition of the lunar mantle
- In-situ characterization of oxalic acid breakdown at elevated P and T: Implications for organic C-O-H fluid sources in petrologic experiments
- Slawsonite-celsian-hyalophane assemblage from a picrite sill (Prague Basin, Czech Republic)
- Determining hematite content from NUV/Vis/NIR spectra: Limits of detection
- The role of water in generation of group II kimberlite magmas: Constraints from multiple saturation experiments
- Quantum mechanical modeling of hydrolysis and H2O-exchange in Mg-, Ca-, and Nisilicate clusters: Implications for dissolution mechanisms of olivine minerals
- Redox-driven exsolution of iron-titanium oxides in magnetite in Miller Range (MIL) 03346 nakhlite: Evidence for post crystallization oxidation in the nakhlite cumulate pile?
- Energetics of lanthanide-doped calcium phosphate apatite
- Thermal conductivity of molten and glassy NaAlSi3O8, CaMgSi2O6, and Mg2SiO4 by non-equilibrium molecular dynamics at elevated temperature and pressure
- Energetics of heterometal substitution in ε-Keggin [MO4Al12(OH)24(OH2)12]6/7/8+ ions
- Ab initio calculations of elastic constants of plagioclase feldspars
- Diagenetic formation of interlayer-deficient fluorophlogopite as a clay mineral in Early Cambrian phosphorite (Lesser Himalaya, India): The trioctahedral analog of illite
- Natural sepiolite: Enthalpies of dehydration, dehydroxylation, and formation derived from thermochemical studies
- A new interpretation of decomposition products of serpentine under shock compression
- model for calculating the viscosity of natural iron-bearing silicate melts over a wide range of temperatures, pressures, oxygen fugacites, and compositions
- The replacement of chalcopyrite by bornite under hydrothermal conditions
- Characterization of porosity in sulfide ore minerals: A USANS/SANS study
- Synthesis of a quenchable high-pressure form of magnetite (h-Fe3O4) with composition Fel(Fe2+0.75Mg0.26)Fe2(Fe3+ 0.70Cr0.15Al0.11Si0.04)2O4
- High-pressure elasticity of sodium majorite garnet, Na2MgSi5O12
- Armstrongite from Khan Bogdo (Mongolia): Crystal structure determination and implications for zeolite-like cation exchange properties
- Steinhardtite, a new body-centered-cubic allotropic form of aluminum from the Khatyrka CV3 carbonaceous chondrite
- New Mineral Names
- Book Review
