Combined effects of jarosite and visible light on chalcopyrite dissolution mediated by Acidithiobacillus ferrooxidans

• Published in: The Science of the total environment Vol. 698; p. 134175
• Main Authors: Yang, Baojun, Lin, Mo, Fang, Jinghua, Zhang, Ruiyong, Luo, Wen, Wang, Xingxing, Liao, Rui, Wu, Baiqiang, Wang, Jun, Gan, Min, Liu, Bin, Zhang, Yi, Liu, Xueduan, Qin, Wenqing, Qiu, Guanzhou
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2020
• Subjects: Acid mine drainage; Acidithiobacillus - metabolism; Acidithiobacillus ferrooxidans; Biodegradation, Environmental; Biodissolution; Chalcopyrite; Copper - chemistry; Ferric Compounds - chemistry; Jarosite; Light; Sulfates - chemistry; Visible light; Acidithiobacillus ferrooxidans; Visible light; Chalcopyrite; Acid mine drainage; Biodissolution; Jarosite
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2019.134175

Although jarosite and visible light are important factors for the formation of acid mine drainage (AMD), the effects of combined jarosite and visible light on chalcopyrite biodissolution have not been explored until now. In order to fill this knowledge gap, the combined effects of jarosite and visible light on chalcopyrite dissolution mediated by Acidithiobacillus ferrooxidans were investigated. The results indicated that jarosite and visible light could significantly accelerate chalcopyrite biodissolution, thus releasing more copper ions, iron ions and producing more acid. This in turn suggests enhanced generation of AMD under these conditions. Biodissolution results, mineral surface morphology, mineralogical phase and elemental composition analyses revealed that the promotion of chalcopyrite dissolution by additional jarosite and visible light was mainly attributed to the acceleration of ferric iron/ferrous iron cycling and the inhibition of the formation of a passivation layer (jarosite and Sn2−/S0) on the surface of chalcopyrite. This study provides a better understanding of the effects of jarosite and visible light on chalcopyrite biodissolution. In the future, the influences of jarosite and visible light on chalcopyrite dissolution should be considered in AMD evaluation to ensure reliability. Visible light and jarosite could significantly accelerate ferric iron/ferrous iron cycling. In addition, additional jarosite could be used as seed crystal to inhibit passivation layer formation on chalcopyrite surface, thus promoting chalcopyrite dissolution. [Display omitted] •The effects of jarosite on chalcopyrite biodissolution was first studied.•Jarosite and visible light could enhance chalcopyrite biodissolution.•Visible light and additional jarosite could accelerate Fe3+/Fe2+ cycling.•Additional jarosite could inhibit passivation layer formation on chalcopyrite surface.