An in situ characterization technique called electrochemical noise(ECN) was used to investigate the bioleaching of natural pyrite.ECN experiments were conducted in four active systems(sulfuric acid,ferric-ion,9k cu...An in situ characterization technique called electrochemical noise(ECN) was used to investigate the bioleaching of natural pyrite.ECN experiments were conducted in four active systems(sulfuric acid,ferric-ion,9k culture medium,and bioleaching solutions).The ECN data were analyzed in both the time and frequency domains.Spectral noise impedance spectra obtained from power spectral density(PSD)plots for different systems were compared.A reaction mechanism was also proposed on the basis of the experimental data analysis.The bioleaching system exhibits the lowest noise resistance of 0.101 MΩ The bioleaching of natural pyrite is considered to be a bio-battery reaction,which distinguishes it from chemical oxidation reactions in ferric-ion and culture-medium(9k) solutions.The corrosion of pyrite becomes more severe over time after the long-term testing of bioleaching.展开更多
Oily wastewater poses significant threats to the soil, water, air and human beings because of the hazardous nature of its oil contents. The objective of this review paper is to highlight the current and recently devel...Oily wastewater poses significant threats to the soil, water, air and human beings because of the hazardous nature of its oil contents. The objective of this review paper is to highlight the current and recently developed methods for oily wastewater treatment through which contaminants such as oil, fats, grease, and inorganics can be removed for safe applications.These include electrochemical treatment, membrane filtration, biological treatment,hybrid technologies, use of biosurfactants, treatment via vacuum ultraviolet radiation,and destabilization of emulsions through the use of zeolites and other natural minerals.This review encompasses innovative and novel approaches to oily wastewater treatment and provides scientific background for future work that will be aimed at reducing the adverse impact of the discharge of oily wastewater into the environment. The current challenges affecting the optimal performance of oily wastewater treatment methods and opportunities for future research development in this field are also discussed.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 51304047 and 51374066)the Ph.D. Programs Foundation of the Ministry of Education of China (No.20130042120040)
文摘An in situ characterization technique called electrochemical noise(ECN) was used to investigate the bioleaching of natural pyrite.ECN experiments were conducted in four active systems(sulfuric acid,ferric-ion,9k culture medium,and bioleaching solutions).The ECN data were analyzed in both the time and frequency domains.Spectral noise impedance spectra obtained from power spectral density(PSD)plots for different systems were compared.A reaction mechanism was also proposed on the basis of the experimental data analysis.The bioleaching system exhibits the lowest noise resistance of 0.101 MΩ The bioleaching of natural pyrite is considered to be a bio-battery reaction,which distinguishes it from chemical oxidation reactions in ferric-ion and culture-medium(9k) solutions.The corrosion of pyrite becomes more severe over time after the long-term testing of bioleaching.
文摘Oily wastewater poses significant threats to the soil, water, air and human beings because of the hazardous nature of its oil contents. The objective of this review paper is to highlight the current and recently developed methods for oily wastewater treatment through which contaminants such as oil, fats, grease, and inorganics can be removed for safe applications.These include electrochemical treatment, membrane filtration, biological treatment,hybrid technologies, use of biosurfactants, treatment via vacuum ultraviolet radiation,and destabilization of emulsions through the use of zeolites and other natural minerals.This review encompasses innovative and novel approaches to oily wastewater treatment and provides scientific background for future work that will be aimed at reducing the adverse impact of the discharge of oily wastewater into the environment. The current challenges affecting the optimal performance of oily wastewater treatment methods and opportunities for future research development in this field are also discussed.