Title of article :
The effect of aqueous sulphate on basaltic glass dissolution rates
Author/Authors :
Therese K. Flaathen، نويسنده , , Therese K. and Gislason، نويسنده , , Sigurًur R. and Oelkers، نويسنده , , Eric H.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2010
Pages :
10
From page :
345
To page :
354
Abstract :
Steady-state dissolution rates of basaltic glass were measured in mixed-flow reactors at 50 °C and 3 < pH < 10 in HCl–NaCl–NH4OH bearing solutions having an ionic strength of 0.01 M, or higher, as a function of aqueous sulphate concentration. Sulphate was added to reactive aqueous solutions in the form of Na2SO4. Measured dissolution rates increase with increased sulphate concentration in acid conditions, but little effect was found in basic conditions. At pH 5, the presence of 0.01 mol/kg sulphate doubled the dissolution rate while 0.10 mol/kg of sulphate tripled the dissolution rate compared to that measured in sulphate-free solutions. This rate increase is found to be consistent with that calculated using an equation previously proposed by Gislason and Oelkers (2003), where the observed rate increase stems from the formation of aqueous Al-sulphate complexes. As the release of divalent cations is thought to be the rate limiting step for CO2 mineralization in basalt, adding aqueous sulphate to injected CO2 could accelerate carbonization processes in this rock during carbon sequestration efforts.
Keywords :
Martian weathering , Basaltic glass , CO2 sequestration , dissolution rates , Kinetics , Aqueous sulphate
Journal title :
Chemical Geology
Serial Year :
2010
Journal title :
Chemical Geology
Record number :
2260103
Link To Document :
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