Abstract
The original abrasion pH test of Stevens and Carron (1948) is based on grinding and wetting of minerals and subsequent pH measurements of the minerals’ paste and suspensions. Such pH values allow insights into the behaviour of individual minerals upon fluid:mineral reactions in surface environments including mine sites and waste repositories. This study proposes a modified abrasion pH method which includes the use of 0.01 M CaCl2, an operationally defined grain size (<0.075 mm), and high precision pH measurements. Several mineral specimens (n = 20) were obtained from commercial suppliers for the modified abrasion pH testwork, with the acquired specimens having a range of purities and resultant pH values. The modified abrasion pH testwork demonstrates that small admixtures to monomineralic samples caused significant pH changes. Only pure monomineralic samples provide a true indication of the modified abrasion pH of that mineral type. The NAGpH method aims to oxidize sulfide minerals but the reliability of this method in waste classification can be compromised depending on the sample mineralogy. This study demonstrates that NAGpH measurements of some carbonate minerals led to very alkaline pH values that are possibly due to the formation of Ca and Mg hydroxides. Such reactions do not occur in waste environments and therefore, NAGpH measurements of carbonate-rich wastes may overestimate their acid buffering capacity .
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References
Charles J, Barnes A, Declercq J, Warrender R, Brough C, Bowell R (2015) Difficulties of interpretation of NAG test results on net neutralizing mine: initial observations of elevated pH conditions and theory of CO2 disequilibrium. In: Proceedings of the 10th international conference on acid rock drainage and IMWA annual conference, 21–24 April 2015, Santiago, Chile, pp 1–10
Faimona J, Stelcl J, Kubesova S, Zimak J (2003) Environmentally acceptable effect of hydrogen peroxide on cave ‘‘lamp-flora’’, calcite speleothems and limestones. Environ Poll 122:417–422
Grant WG (1969) Abrasion pH, an index of chemical weathering. Clays Clay Miner 17:151–155
Hammarstrom JM, Seal RR II, Meier AL, Kornfeld JM (2005) Secondary sulphate minerals associated with acid drainage in the eastern US: recycling of metals and acidity in surficial environments. Chem Geol 215:407–431
Jennings SR, Dollhop JD, Inskeep WP (2000) Acid production from sulfide minerals using hydrogen peroxide weathering. Appl Geochem 15:235–243
Jerz JK, Rimstidt JD (2003) Efflorescent iron sulfate minerals: Paragenesis, relative stability, and environmental impact. Am Mineral 88:1919–1932
Lottermoser BG (2010) Mine wastes: characterization, treatment and environmental impacts, 3rd edn. Springer, Berlin
Noble TL, Parbhakar-Fox A, Lottermoser BG (2016) pH Testing Methods for Sulfidic Mine Wastes. In: Lottermoser B (ed) Environmental Indicators in Metal Mining, Springer, Switzerland. doi:10.1007/978-3-319-42731-7_11
Price WA (2009) Prediction manual for drainage chemistry from sulphidic geologic materials. CANMET Mining and Mineral Sciences Laboratories, Canada
Smart R, Skinner B, Levay G, Gerson A, Thomas J, Sobieraj H, Schumann R, Weisener C, Weber P, Miller S, Stewart W (2002) ARD test handbook. AMIRA P387A, prediction and kinetic control of acid mine drainage. AMIRA International Ltd, Melbourne
Stevens RE, Carron MK (1948) Simple field test for distinguishing minerals by abrasion pH. Am Mineral 33:31–50
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Noble, T.L., Lottermoser, B. (2017). Modified Abrasion pH and NAGpH Testing of Minerals. In: Lottermoser, B. (eds) Environmental Indicators in Metal Mining. Springer, Cham. https://doi.org/10.1007/978-3-319-42731-7_12
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DOI: https://doi.org/10.1007/978-3-319-42731-7_12
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