Fe2＋ oxidation by Acidithiobacillus ferrooxidans（At.ferrooxidans） under different solid contents by adding inert Al2O3 powder was examined in rotating-drum and stirred-tank reactors.The results show that the bioact...Fe2＋ oxidation by Acidithiobacillus ferrooxidans（At.ferrooxidans） under different solid contents by adding inert Al2O3 powder was examined in rotating-drum and stirred-tank reactors.The results show that the bioactivity of At.ferrooxidans in the stirred-tank is higher than that in the rotating-drum in the absence of Al2O3 powder,but the biooxidation rate of Fe2＋ decreases markedly from 0.23 g/（L·h） to 0.025 g/（L·h） with increasing the content of Al2O3 powder from 0 to 50%（mass fraction） in the stirred-tank probably due to the deactivation of At.ferrooxidans resulting from the collision and friction of solid particles.The increase in Al2O3 content has a little adverse effect on the bioactivity of At.ferrooxidans in the rotating-drum due to different mixing mechanisms of the two reactors.The biooxidation rate of Fe2＋ in the rotating-drum is higher than that in the stirred-tank at the same content of Al2O3 powder,especially at high solid content.The higher bioactivity of At.ferrooxidans can be maintained for allowing high solid content in the rotating-drum reactor,but its application potential still needs to be verified further by the sulfide bioleaching for the property differences of Al2O3 powder and sulfide minerals.展开更多
The adsorption equilibrium of a fluoride solution on 1-2 mm granular activated alumina modified by Fe2(SO4)3 solution was investigated.The experiments were conducted using a wide range of initial fluoride concentratio...The adsorption equilibrium of a fluoride solution on 1-2 mm granular activated alumina modified by Fe2(SO4)3 solution was investigated.The experiments were conducted using a wide range of initial fluoride concentrations(0.5 to 180 mg·L-1 at pH～7.0) and an adsorbent dose of 1.0 g·L-1.The application of Langmuir and Freundlich adsorption isotherm models(linear and nonlinear forms) generally showed that a single Langmuir or Freundlich equation cannot fit the entire concentration gap.Experimental data on low equilibrium concentrations(0.1 to 5.0 mg·L-1) was in line with both Langmuir and Freundlich isotherm models,whereas that of high equilibrium concentrations(5.0 to 150 mg·L-1) was more in line with the Freundlich isotherm model.A new LangmuirFreundlich function was used for the entire concentration gap,as well as for low and high concentrations.展开更多
基金Project(2010CB630904) supported by the National Basic Research Program of ChinaProject(5102030) supported by the Beijing Natural Science Foundation,China+1 种基金Projects(21076214,21006108) supported by the National Natural Science Foundation of ChinaProject supported by the Open Funding Project of the State Key Laboratory of Bioreactor Engineering,China
文摘Fe2＋ oxidation by Acidithiobacillus ferrooxidans（At.ferrooxidans） under different solid contents by adding inert Al2O3 powder was examined in rotating-drum and stirred-tank reactors.The results show that the bioactivity of At.ferrooxidans in the stirred-tank is higher than that in the rotating-drum in the absence of Al2O3 powder,but the biooxidation rate of Fe2＋ decreases markedly from 0.23 g/（L·h） to 0.025 g/（L·h） with increasing the content of Al2O3 powder from 0 to 50%（mass fraction） in the stirred-tank probably due to the deactivation of At.ferrooxidans resulting from the collision and friction of solid particles.The increase in Al2O3 content has a little adverse effect on the bioactivity of At.ferrooxidans in the rotating-drum due to different mixing mechanisms of the two reactors.The biooxidation rate of Fe2＋ in the rotating-drum is higher than that in the stirred-tank at the same content of Al2O3 powder,especially at high solid content.The higher bioactivity of At.ferrooxidans can be maintained for allowing high solid content in the rotating-drum reactor,but its application potential still needs to be verified further by the sulfide bioleaching for the property differences of Al2O3 powder and sulfide minerals.
基金Supported by the Major National Science and Technology Special Project on Treatment and Control of Water Pollution(2009ZX07425-006)the State Key laboratory of Environmental Simulation and Pollution Control (09K04ESPCT)
文摘The adsorption equilibrium of a fluoride solution on 1-2 mm granular activated alumina modified by Fe2(SO4)3 solution was investigated.The experiments were conducted using a wide range of initial fluoride concentrations(0.5 to 180 mg·L-1 at pH～7.0) and an adsorbent dose of 1.0 g·L-1.The application of Langmuir and Freundlich adsorption isotherm models(linear and nonlinear forms) generally showed that a single Langmuir or Freundlich equation cannot fit the entire concentration gap.Experimental data on low equilibrium concentrations(0.1 to 5.0 mg·L-1) was in line with both Langmuir and Freundlich isotherm models,whereas that of high equilibrium concentrations(5.0 to 150 mg·L-1) was more in line with the Freundlich isotherm model.A new LangmuirFreundlich function was used for the entire concentration gap,as well as for low and high concentrations.
