The leaching kinetics of copper from low-grade copper ore was investigated in ammonia-ammonium sulfate solution with sodium persulfate. The effect parameters of stirring speed, temperature, particle size, concentratio...The leaching kinetics of copper from low-grade copper ore was investigated in ammonia-ammonium sulfate solution with sodium persulfate. The effect parameters of stirring speed, temperature, particle size, concentrations of ammonia, ammonium sulfate and sodium persulfate were determined. The results show that the leaching rate is nearly independent of agitation above 300 r/min and increases with the increase of temperature, concentrations of ammonia, ammonium sulfate and sodium persulfate. The EDS analysis and phase quantitative analysis of the residues indicate that bornite can be dissolved by persulfate oxidization. The leaching kinetics with activation energy of 22.91 kJ/mol was analyzed by using a new shrinking core model （SCM） in which both the interfacial transfer and diffusion across the product layer affect the leaching rate. A semi-empirical rate equation was obtained to describe the leaching process and the empirical reaction orders with respect to the concentrations of ammonia, ammonium sulfate and sodium persulfate are 0.5, 1.2 and 0.5, respectively.展开更多
In recent years,with the emergence of new pollutants,the effective treatment of wastewater has become very important.Persulfate-based advanced oxidation processes have been successfully applied to the treatment of was...In recent years,with the emergence of new pollutants,the effective treatment of wastewater has become very important.Persulfate-based advanced oxidation processes have been successfully applied to the treatment of wastewater,such as wastewater containing antibiotics,pharmaceuticals and personal care products,dyes,endocrine-disrupting chemicals,chlorinated organic pollutants,and phenolics,for the degradation of refractory organic contaminants.This paper summarizes the production of sulfate radicals,which can be generated by the activation of persulfate via conventional and emerging approaches.The existing problems of persulfate-based advanced oxidation processes were analyzed in detail,including residual sulfates,coexisting factors(coexisting inorganic anions and natural organic matter),and energy consumption.This paper proposes corresponding possible solutions to the problems mentioned above,and this paper could provide a reference for the application of persulfate-based advanced oxidation processes in actual wastewater treatment.展开更多
基金Project(2007CB613601)supported by the National Basic Research Program of ChinaProject(10C1095)supported by the Foundation of Hunan Educational Committee,China
文摘The leaching kinetics of copper from low-grade copper ore was investigated in ammonia-ammonium sulfate solution with sodium persulfate. The effect parameters of stirring speed, temperature, particle size, concentrations of ammonia, ammonium sulfate and sodium persulfate were determined. The results show that the leaching rate is nearly independent of agitation above 300 r/min and increases with the increase of temperature, concentrations of ammonia, ammonium sulfate and sodium persulfate. The EDS analysis and phase quantitative analysis of the residues indicate that bornite can be dissolved by persulfate oxidization. The leaching kinetics with activation energy of 22.91 kJ/mol was analyzed by using a new shrinking core model （SCM） in which both the interfacial transfer and diffusion across the product layer affect the leaching rate. A semi-empirical rate equation was obtained to describe the leaching process and the empirical reaction orders with respect to the concentrations of ammonia, ammonium sulfate and sodium persulfate are 0.5, 1.2 and 0.5, respectively.
基金the National Natural Science Foundation of China(No.51678185)Talents of High Level Scientific Research Foundation of Qingdao Agricultural University(No.6651120004).
文摘In recent years,with the emergence of new pollutants,the effective treatment of wastewater has become very important.Persulfate-based advanced oxidation processes have been successfully applied to the treatment of wastewater,such as wastewater containing antibiotics,pharmaceuticals and personal care products,dyes,endocrine-disrupting chemicals,chlorinated organic pollutants,and phenolics,for the degradation of refractory organic contaminants.This paper summarizes the production of sulfate radicals,which can be generated by the activation of persulfate via conventional and emerging approaches.The existing problems of persulfate-based advanced oxidation processes were analyzed in detail,including residual sulfates,coexisting factors(coexisting inorganic anions and natural organic matter),and energy consumption.This paper proposes corresponding possible solutions to the problems mentioned above,and this paper could provide a reference for the application of persulfate-based advanced oxidation processes in actual wastewater treatment.
