A method for preparation and cleaning of uniformly sized arsenopyrite particles

Geochemical Transactions

Methodology

Hariprasad Parthasarathy¹  David A Dzombak¹  Athanasios K Karamalidis¹  John P Baltrus² 

[1] Department of Civil and Environmental Engineering, Carnegie Mellon University, 15213, Pittsburgh, PA, USA;U.S. Department of Energy, National Energy Technology Laboratory, 15236, Pittsburgh, PA, USA;

关键词: Arsenopyrite;    XPS;    Mineral preparation;    Surface cleaning;    Oxidation;   

DOI  :  10.1186/s12932-014-0014-9

 received in 2014-05-14, accepted in 2014-10-02,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundThe oxidative dissolution of sulfide minerals, such as arsenopyrite (FeAsS), is of critical importance in many geochemical systems. A comprehensive understanding of their dissolution rates entails careful preparation of the mineral surface. Measurements of dissolution rates of arsenic from arsenopyrite are dependent on the size and degree of oxidation of its particles, among other factors. In this work, a method was developed for preparation and cleaning of arsenopyrite particles with size range of 15-250 μm. Four different cleaning methods were evaluated for effectiveness based on the removal of oxidized species of iron (Fe), arsenic (As) and sulfur (S) from the surface. The percentage oxidation of the surface was determined using X-ray photoelectron spectroscopy (XPS), and surface stoichiometry was measured using scanning electron microscopy - energy dispersive X-ray spectroscopy (SEM-EDS).ResultsResults indicate that sonicating the arsenopyrite particles and then cleaning them with 12N HCl followed by 50% ethanol, and drying in nitrogen was the most effective method. This method was successful in greatly reducing the oxide species of Fe while completely removing oxides of As and S from the arsenopyrite surface.ConclusionsAlthough sonication and acid cleaning have been widely used for mineral preparation, the method described in this study can significantly reduce grain size heterogeneity as well as surface oxidation, which enables greater control in surface and dissolution experiments.

【 授权许可】

Unknown   
© Parthasarathy et al.; licensee Springer. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.