Electrochemical reduction of air-abundant molecules(e.g.,CO_(2),N_(2),and O_(2))offers a sustainable solution to address global energy and environmental challenges,where high current density and energy efficiency are ...Electrochemical reduction of air-abundant molecules(e.g.,CO_(2),N_(2),and O_(2))offers a sustainable solution to address global energy and environmental challenges,where high current density and energy efficiency are highly desirable.However,commercially-relevant current density will cause dramatic change of cation,solvent,p H,and reactant molecular distribution near electrode,resulting in severe concentration polarization and sluggish reaction kinetics.In this case,mass transfer such as molecule migration pathway in electrolytes,electrodes,and devices need to be rationally designed and systematically optimized.Here this review will present a systematical introduction on regulating mass transfer on electrochemical fixation of air-abundant molecules.We firstly discuss the fundamental mass transport from bulk electrolyte to catalyst surface and within electric double layer(EDL)and review the recent advances in regulating mass transport behaviors and optimizing strategy of mass transfer on the catalytic surface.Then we compare the mass transport differences among different cell architectures combining with innovative prospect for transfer pathway towards breaking natural limitation of gas solubility over electroactive interfaces.It is expected that this review can inspire research on comprehensive understanding of fundamental mass transport mechanism at catalyst/electrolyte interface and shed light on optimizing the catalytical device towards practical application for electrochemical fixation of air-abundant molecules.展开更多
In order to better understand the leaching process of rare earth （RE） and aluminum （Al） from the weathered crust elutiondepositedRE ore, the mass transfer of RE and Al in column leaching was investigated using the...In order to better understand the leaching process of rare earth （RE） and aluminum （Al） from the weathered crust elutiondepositedRE ore, the mass transfer of RE and Al in column leaching was investigated using the chromatographic plate theory. Theresults show that a higher initial ammonium concentration in a certain range can enhance the mass transfer process. pH of leachingagent in the range of 2 to 8 almost has no effect on the mass transfer efficiency of RE, but plays a positive role in the mass transferefficiency of Al under strong acidic condition （pH〈4）. There is an optimum flow rate that makes the highest mass transfer efficiency.The optimum leaching condition of RE is the leaching agent pH of 4？8, ammonium concentration of 0.4 mol/L and flow rate of0.5 mL/min. The mass transfer efficiencies of RE and Al both follow the order： （NH4）2SO4〈NH4Cl〈NH4NO3, implying thecomplexing ability of anion.展开更多
A novel surface aeration configuration featured with aself-rotating and floating baffle (SRFB) and a Rushton disk turbine(DT) with a perforated disk has been developed. The SRFB, consistedof 12 fan blades twisted By a...A novel surface aeration configuration featured with aself-rotating and floating baffle (SRFB) and a Rushton disk turbine(DT) with a perforated disk has been developed. The SRFB, consistedof 12 fan blades twisted By an angle of 30 deg to the horizontalplane, is incorporated onto the impeller shaft to improve gasentrainment, bubble Breakup, mixing in a φ 154 mm agitated vessel.This new configuration is compared to the conventional DT surfaceAeration experimentally. The results suggest that the criticalimpeller speed for onset of gas entrainment is lower for The newconfiguration and it demands greater power consumption. Moreover, theSRFB system produces 30/100-168/100 Higher volumetric mass transfercoefficient per unit power input than that obtained in theconventional DT surface Aerator under the same operation conditions.展开更多
基金the support from the National Natural Science Foundation of China(Nos.22375103,22105107)Ministry of Science and Technology of China(No.2021YFA1201900)the Fundamental Research Funds for the Central Universities。
文摘Electrochemical reduction of air-abundant molecules(e.g.,CO_(2),N_(2),and O_(2))offers a sustainable solution to address global energy and environmental challenges,where high current density and energy efficiency are highly desirable.However,commercially-relevant current density will cause dramatic change of cation,solvent,p H,and reactant molecular distribution near electrode,resulting in severe concentration polarization and sluggish reaction kinetics.In this case,mass transfer such as molecule migration pathway in electrolytes,electrodes,and devices need to be rationally designed and systematically optimized.Here this review will present a systematical introduction on regulating mass transfer on electrochemical fixation of air-abundant molecules.We firstly discuss the fundamental mass transport from bulk electrolyte to catalyst surface and within electric double layer(EDL)and review the recent advances in regulating mass transport behaviors and optimizing strategy of mass transfer on the catalytic surface.Then we compare the mass transport differences among different cell architectures combining with innovative prospect for transfer pathway towards breaking natural limitation of gas solubility over electroactive interfaces.It is expected that this review can inspire research on comprehensive understanding of fundamental mass transport mechanism at catalyst/electrolyte interface and shed light on optimizing the catalytical device towards practical application for electrochemical fixation of air-abundant molecules.
基金Projects(51274152,41472071)supported by the National Natural Science Foundation of ChinaProject(T201506)supported by the Program for Excellent Young Scientific and Technological Innovation Team of Hubei Provincial Department of Education,China
文摘In order to better understand the leaching process of rare earth （RE） and aluminum （Al） from the weathered crust elutiondepositedRE ore, the mass transfer of RE and Al in column leaching was investigated using the chromatographic plate theory. Theresults show that a higher initial ammonium concentration in a certain range can enhance the mass transfer process. pH of leachingagent in the range of 2 to 8 almost has no effect on the mass transfer efficiency of RE, but plays a positive role in the mass transferefficiency of Al under strong acidic condition （pH〈4）. There is an optimum flow rate that makes the highest mass transfer efficiency.The optimum leaching condition of RE is the leaching agent pH of 4？8, ammonium concentration of 0.4 mol/L and flow rate of0.5 mL/min. The mass transfer efficiencies of RE and Al both follow the order： （NH4）2SO4〈NH4Cl〈NH4NO3, implying thecomplexing ability of anion.
基金Supported by the National Natural Science Foundation of China (No. 29792074) and SINOPEC.
文摘A novel surface aeration configuration featured with aself-rotating and floating baffle (SRFB) and a Rushton disk turbine(DT) with a perforated disk has been developed. The SRFB, consistedof 12 fan blades twisted By an angle of 30 deg to the horizontalplane, is incorporated onto the impeller shaft to improve gasentrainment, bubble Breakup, mixing in a φ 154 mm agitated vessel.This new configuration is compared to the conventional DT surfaceAeration experimentally. The results suggest that the criticalimpeller speed for onset of gas entrainment is lower for The newconfiguration and it demands greater power consumption. Moreover, theSRFB system produces 30/100-168/100 Higher volumetric mass transfercoefficient per unit power input than that obtained in theconventional DT surface Aerator under the same operation conditions.
