کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5779256 | 1634387 | 2017 | 5 صفحه PDF | دانلود رایگان |
One of the most significant environmental variables that affect albite dissolution rate is deviation from equilibrium (ÎGr). Most of the studies that describe the effect of ÎGr on albite dissolution rate were conducted under alkline pH (8.8-9.2), elvetad temperatures (80-300 °C) and for Amelia Courthouse (USA) albite. Comparison of the f(ÎGr) derived from those studies to the only f(ÎGr) from low temperature (25 °C), circum neutral pH and EVJE (Norway) albite leads to different ÎGr functions. Yet, except for the study of1, rate laws for silicate minerals dissolution, which are based on experiments conducted under ambient conditions, are lacking. Here we present new experimental results of single point batch experiments (SPBE) of albite dissolution in a isotopically spiked solution. The novel method that use Si isotopes2 enables detecting rates that otherwise can't be detected under ambient conditions. Albite dissolution rates were determined under neutral-acidic pH, temperatures of 3.6, 25 and 50 °C, and a wide range of undersaturation conditions. The dependency of the dissolution rate on deviation from equilibrium (f(ÎGr)) was in agreement with the prediction of previous studies. However, the value of ÎGcrit was found to be significantly different, suggesting an effect of extrinsic properties of the environment.
Journal: Procedia Earth and Planetary Science - Volume 17, 2017, Pages 148-152