The apparent sulfur oxidation activities of four pure thermophilic archaea, Acidianus brierleyi (JCM 8954), Metallosphaera sedula (YN 23), Acidianus manzaensis (YN 25) and Sulfolobus metallicus (YN 24) and the...The apparent sulfur oxidation activities of four pure thermophilic archaea, Acidianus brierleyi (JCM 8954), Metallosphaera sedula (YN 23), Acidianus manzaensis (YN 25) and Sulfolobus metallicus (YN 24) and their mixture in bioleaching chalcopyrite were compared, which were characterized indirectly by the evolution of the cells concentration, pH value and sulfate ions concentration in solution. The results show that the mixed culture contributed significantly to the raising of leaching rate, which suggests that the mixed culture had a higher sulfur oxidation activity than the pure culture. Meanwhile, the results also indicate that the changes of parameters characterizing the sulfur oxidation activity of thermophilic archaea are often influenced by many factors, so it is hard to reflect accurately the specific sulfur oxidation activities among the different sulfur-oxidizing microbes when bioleaching chalcopyrite at different conditions. Accordingly, an efficient method to characterize microbial sulfur oxidation activity appears to be desirable.展开更多
The relatedness between catalytic effect of activated carbon and passivation phenomenon during chalcopyrite bioleachingby mixed thermophilic Archaea culture(Acidianus brierleyi,Metallosphaera sedula,Acidianus manzaens...The relatedness between catalytic effect of activated carbon and passivation phenomenon during chalcopyrite bioleachingby mixed thermophilic Archaea culture(Acidianus brierleyi,Metallosphaera sedula,Acidianus manzaensis and Sulfolobusmetallicus)at65°C was studied.Leaching experiments showed that the addition of activated carbon could significantly promote thedissolution of chalcopyrite for both bioleaching and chemical leaching.The results of synchrotron-based X-ray diffraction,ironL-edge and sulfur K-edge X-ray absorption near edge structure spectroscopy indicated that activated carbon could change thetransition path of electrons through galvanic interactions to form more readily dissolved secondary mineral chalcocite at a low redoxpotential(?400mV)and then enhanced the copper dissolution.Jarosite accumulated immediately in the initial stage of bioleachingwith activated carbon but copper dissolution was not hindered.However,much jarosite precipitated on the surface of chalcopyrite inthe late stage of bioleaching,which might account for the decrease of copper dissolution rate.More elemental sulfur(S0)was alsodetected with additional activated carbon but the mixed thermophilic Archaea culture had a great sulfur oxidation activity,thus S0waseliminated and seemed to have no significant influence on the dissolution of chalcopyrite.展开更多
The adsorption and leaching of chalcopyrite by two extreme thermophilic archaea(A.brierleyi and S.metallicus)and their mixture were studied.The results revealed that the chalcopyrite leaching rate of S.metallicus was ...The adsorption and leaching of chalcopyrite by two extreme thermophilic archaea(A.brierleyi and S.metallicus)and their mixture were studied.The results revealed that the chalcopyrite leaching rate of S.metallicus was slightly higher than that of A.brierleyi;the mixed system showed the highest rate.Community structure analysis during the leaching process showed that S.metallicus was maintained in a predominant state.However,the proportion of A.brierleyi in the community increased during leaching.Copper concentrations,which increased faster in the mixed system than in the single-organism systems during later stages,was related to the change of A.brierleyi in the community.Langmuir parameter analysis revealed no competitive adsorption between these two thermophilic archaea.Furthermore,qPCR(quantitative polymerase chain reaction)confirmed that adsorption was promoted between A.brierleyi and S.metallicus during mixed leaching.These findings can improve our understanding of the adsorption behaviors of mixed extreme microbial populations on mineral surfaces.展开更多
基金Project(50974140) supported by the National Natural Science Foundation of ChinaProject(20090162110054) supported by Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘The apparent sulfur oxidation activities of four pure thermophilic archaea, Acidianus brierleyi (JCM 8954), Metallosphaera sedula (YN 23), Acidianus manzaensis (YN 25) and Sulfolobus metallicus (YN 24) and their mixture in bioleaching chalcopyrite were compared, which were characterized indirectly by the evolution of the cells concentration, pH value and sulfate ions concentration in solution. The results show that the mixed culture contributed significantly to the raising of leaching rate, which suggests that the mixed culture had a higher sulfur oxidation activity than the pure culture. Meanwhile, the results also indicate that the changes of parameters characterizing the sulfur oxidation activity of thermophilic archaea are often influenced by many factors, so it is hard to reflect accurately the specific sulfur oxidation activities among the different sulfur-oxidizing microbes when bioleaching chalcopyrite at different conditions. Accordingly, an efficient method to characterize microbial sulfur oxidation activity appears to be desirable.
基金Project(51274257) supported by the National Natural Science Foundation of ChinaProject(U1232103) supported by the Joint Funds of National Natural Science Foundation of China and Large Scientific Facility Foundation of Chinese Academy of Sciences+1 种基金Project(VR-12419) supported by the Beijing Synchrotron Radiation Facility Public User Program,ChinaProject(15ssrf00924) supported by the Shanghai Institute of Applied Physics Open Fund of Shanghai Synchrotron Radiation Facility,China
文摘The relatedness between catalytic effect of activated carbon and passivation phenomenon during chalcopyrite bioleachingby mixed thermophilic Archaea culture(Acidianus brierleyi,Metallosphaera sedula,Acidianus manzaensis and Sulfolobusmetallicus)at65°C was studied.Leaching experiments showed that the addition of activated carbon could significantly promote thedissolution of chalcopyrite for both bioleaching and chemical leaching.The results of synchrotron-based X-ray diffraction,ironL-edge and sulfur K-edge X-ray absorption near edge structure spectroscopy indicated that activated carbon could change thetransition path of electrons through galvanic interactions to form more readily dissolved secondary mineral chalcocite at a low redoxpotential(?400mV)and then enhanced the copper dissolution.Jarosite accumulated immediately in the initial stage of bioleachingwith activated carbon but copper dissolution was not hindered.However,much jarosite precipitated on the surface of chalcopyrite inthe late stage of bioleaching,which might account for the decrease of copper dissolution rate.More elemental sulfur(S0)was alsodetected with additional activated carbon but the mixed thermophilic Archaea culture had a great sulfur oxidation activity,thus S0waseliminated and seemed to have no significant influence on the dissolution of chalcopyrite.
基金Project (51774342) supported by the National Natural Science Foundation of ChinaProject (2016RS2016) supproted by the Hunan Provincial Science and Technology Leader (Innovation Team of Interface Chemistry of Efficient and Clean Utilization of Complex Mineral Resources),China
文摘The adsorption and leaching of chalcopyrite by two extreme thermophilic archaea(A.brierleyi and S.metallicus)and their mixture were studied.The results revealed that the chalcopyrite leaching rate of S.metallicus was slightly higher than that of A.brierleyi;the mixed system showed the highest rate.Community structure analysis during the leaching process showed that S.metallicus was maintained in a predominant state.However,the proportion of A.brierleyi in the community increased during leaching.Copper concentrations,which increased faster in the mixed system than in the single-organism systems during later stages,was related to the change of A.brierleyi in the community.Langmuir parameter analysis revealed no competitive adsorption between these two thermophilic archaea.Furthermore,qPCR(quantitative polymerase chain reaction)confirmed that adsorption was promoted between A.brierleyi and S.metallicus during mixed leaching.These findings can improve our understanding of the adsorption behaviors of mixed extreme microbial populations on mineral surfaces.