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RDF description of Chemical and surface analysis during evolution of arsenopyrite oxidation by Acidithiobacillus thiooxidans in the presence and absence of supplementary arsenic - http://orbis.uaslp.mx/vivo/individual/scopus4838
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Consejo Nacional de Ciencia y Tecnología, CONACYT
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arsenic, 7440-38-2; pyrite, 1309-36-0; sulfide, 18496-25-8; Arsenic; Arsenicals; arsenopyrite; Iron Compounds; Minerals; Sulfides; Water Pollutants, Chemical
Bioleaching of arsenopyrite presents a great interest due to recovery of valuable metals and environmental issues. The current study aims to evaluate the arsenopyrite oxidation by Acidithiobacillus thiooxidans during 240 h at different time intervals, in the presence and absence of supplementary arsenic. Chemical and electrochemical characterizations are carried out using Raman, AFM, SEM-EDS, Cyclic Voltammetry, EIS, electrophoretic and adhesion forces to comprehensively assess the surface behavior and biooxidation mechanism of this mineral. These analyses evidence the formation of pyrite-like secondary phase on abiotic control surfaces, which contrast with the formation of pyrite (FeS2)-like, orpiment (As2S3)-like and elementary sulfur and polysulfide (Sn2 −/S0) phases found on biooxidized surfaces. Voltammetric results indicate a significant alteration of arsenopyrite due to (bio)oxidation. Resistive processes determined with EIS are associated with chemical and electrochemical reactions mediated by (bio)oxidation, resulting in the transformation of arsenopyrite surface and biofilm direct attachment. Charge transfer resistance is increased when (bio)oxidation is performed in the presence of supplementary arsenic, in comparison with lowered abiotic control resistances obtained in its absence; reinforcing the idea that more stable surface products are generated when As(V) is in the system. Biofilm structure is mainly comprised of micro-colonies, progressively enclosed in secondary compounds. A more compact biofilm structure with enhanced formation of secondary compounds is identified in the presence of supplementary arsenic, whereby variable arsenopyrite reactivity is linked and attributed to these secondary compounds, including Sn2 −/S0, pyrite-like and orpiment-like phases. © 2016 Elsevier B.V.
Chemical and surface analysis during evolution of arsenopyrite oxidation by Acidithiobacillus thiooxidans in the presence and absence of supplementary arsenic
Acidithiobacillus thiooxidans; Arsenopyrite biooxidation; Biofilm modification; Direct cell attachment; Electrochemical impedance spectroscopy; Toxic arsenic Arsenic; Biofilms; Charge transfer; Chemical analysis; Cyclic voltammetry; Electrochemical impedance spectroscopy; Metal recovery; Oxidation; Pyrites; Surface analysis; Acidithiobacillus thiooxidans; Bio-oxidation; Cell attachments; Charge transfer resistance; Electrochemical characterizations; Electrochemical reactions; Recovery of valuable metals; Toxic arsenic; Arsenic compounds; arsenic; arsenic derivative; arsenopyrite; orpiment; polysulfide; pyrite; sulfur derivative; unclassified drug; arsenic; arsenopyrite; iron derivative; mineral; organoarsenic derivative; sulfide; arsenic; arsenopyrite; bacterium; biofilm; chemical analysis; electrochemistry; oxidation; Acidithiobacillus thiooxidans; adhesion; Article; atomic force microscopy; biofilm; chemical analysis; chemical reaction; controlled study; cyclic potentiometry; electrochemical impedance spectroscopy; electrochemistry; electrophoresis; nonhuman; oxidation; priority journal; Raman spectrometry; scanning electron microscopy; surface property; Acidithiobacillus thiooxidans; biofilm; bioremediation; chemistry; metabolism; oxidation reduction reaction; physiology; time factor; water pollutant; Acidithiobacillus thiooxidans; Acidithiobacillus thiooxidans; Arsenic; Arsenicals; Biodegradation, Environmental; Biofilms; Iron Compounds; Minerals; Oxidation-Reduction; Sulfides; Time Factors; Water Pollutants, Chemical