The increasing emission of carbon dioxide (CO2) caused by the unrestrained consumption of fossil fuels in recent hundreds of years, has caused global environmental and social problems. Meanwhile, CO2 is a cheap, abu...The increasing emission of carbon dioxide (CO2) caused by the unrestrained consumption of fossil fuels in recent hundreds of years, has caused global environmental and social problems. Meanwhile, CO2 is a cheap, abundant and renewable Cl-feedstock, which can be converted into alco- hols, ethers, acids and other value-added chemicals. Compared with the thermal reactions, electrochemical reduction of CO2 is more attractive because of its advantages by using the seasonal, geographical and intermittent energy (tide, wind and solar) under mild conditions. In recent years, taking ionic liquids (ILs) as electrolytes in the CO2 electrochemical reduction reaction has been paid much more attention due to the advantages of lowering the overpotential of CO2 electroreduction and improving the Faradaic efficiency. In this paper, we summarized the recent progresses of electrochemical re- duction of CO2 in ILs electrolytes, and analyzed the reaction mechanism of CO2 reaction in the electrode-electrolyte interface region by experimental and simulation methods. Finally, the research which needs to be highlighted in this area was proposed.展开更多
The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performa...The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performance was investigated in a fixed-bed system with respect to the adsorption superficial velocity,ionic strength and pH.A mathematical model was used to simulate the mass transfer mechanism,taking film mass transfer,pore diffusion and axial dispersion into account.The model predictions were consistent with the experi-mental data and were consequently used to determine the mass transfer coefficients.展开更多
To improve the low-temperature performances of Li-ion cells, three types of linear carboxylic ester-based electrolyte, such as EC/EMC/EA(1:1:2, mass ratio), EC/EMC/EP(1:1:2, mass ratio) and EC/EMC/EB(1:1:2,...To improve the low-temperature performances of Li-ion cells, three types of linear carboxylic ester-based electrolyte, such as EC/EMC/EA(1:1:2, mass ratio), EC/EMC/EP(1:1:2, mass ratio) and EC/EMC/EB(1:1:2, mass ratio), were prepared to substitute for industrial electrolyte(EC/EMC/DMC). Then, 18650-type Li Mn2O4-graphite cells(nominal capacity of 1150 mA ·h) were assembled and studied. Results show that the cells containing three types of electrolyte are able to undertake 5C discharging current with above 93% capacity retention at-20 °C. Electrochemical impedance spectra show that the discharge capacity fading of Li-ion cells at low temperature is mainly ascribed to the charge transfer resistance increasing with temperature decreasing. In comparison, the cells containing electrolyte of 1.0 mol/L LiPF6 in EC/EMC/EA(1:1:2, mass ratio) have the highest capacity retention of 90% at-40 °C and 44.41% at-60 °C, due to its lowest charge-transfer resistance.展开更多
Ionic liquids have been used as catalysts for Blanc reaction of toluene. The effects of reaction temperature, reaction time and dosage of the ionic liquid catalyst have been investigated, and the catalytic performance...Ionic liquids have been used as catalysts for Blanc reaction of toluene. The effects of reaction temperature, reaction time and dosage of the ionic liquid catalyst have been investigated, and the catalytic performance of different ionic liquid catalysts for toluene chloromethylation was also studied. The reaction was found to proceed under mild conditions with excellent conversion (up to 90%) in the absence of Lewis acids. The ionic liquids could be recycled and reused without loss of their catalytic activities.展开更多
Recovery of carbon monoxide from flue gases by selective absorption of carbon monoxide in an imidazolium chlorocuprate(l) ionic liquid is considered in this work as an alternative to the use of molecular volatile so...Recovery of carbon monoxide from flue gases by selective absorption of carbon monoxide in an imidazolium chlorocuprate(l) ionic liquid is considered in this work as an alternative to the use of molecular volatile solvents such as aromatic hydrocarbons. The present work evaluates the CO mass transfer rates from the gas phase to the ionic liquid solutions in the absence of chemical reaction. To that end, carbon dioxide was employed as an inert model gas and absorption experiments were performed to assess the influence of different process variables in a batch reactor with fiat gas-liquid interface. The experimental mass transfer coefficients showed significant var- iation with temperature, (3.4-10.9) × 10^-7 m·s^-1 between 293 and 313 K; stirring speed, (10.2- 33.1)× 10^-7 m.s 1 between 100 and 300 r·min^-1; and concentration of copper(1), (6.6-10.2) × 10^-7 m·s^-1 between 0.25 and 2 mol· L^- 1. In addition, the mass transfer coefficients were eventually found to follow a poten- tial proportionality of the type kL ∝μ^-0.5 and the dimensionless correlation that makes the estimation of the mass transfer coefficients possible in the studied range of process variables was obtained: Sh=10^-2.64 Re^1.07 , Sc^0.75,These results constitute the first step in the kinetic analysis of the reaction between CO and imidazolium chlorocuprate(I) ionic liquid that determines the design of the separation units.展开更多
基金This work was supported by Fundamental Research and the National Key Projects for Development of China (2018YFB0605802), the National Natural Science Foundation of China (21425625 & 21506219), Beijing Natural Science Founda- tion (2182072), the Research Council of Norway {267615), and Beijing Hundreds of Leading Talents Training Project of Science and Technology (Z171100001117154).
文摘The increasing emission of carbon dioxide (CO2) caused by the unrestrained consumption of fossil fuels in recent hundreds of years, has caused global environmental and social problems. Meanwhile, CO2 is a cheap, abundant and renewable Cl-feedstock, which can be converted into alco- hols, ethers, acids and other value-added chemicals. Compared with the thermal reactions, electrochemical reduction of CO2 is more attractive because of its advantages by using the seasonal, geographical and intermittent energy (tide, wind and solar) under mild conditions. In recent years, taking ionic liquids (ILs) as electrolytes in the CO2 electrochemical reduction reaction has been paid much more attention due to the advantages of lowering the overpotential of CO2 electroreduction and improving the Faradaic efficiency. In this paper, we summarized the recent progresses of electrochemical re- duction of CO2 in ILs electrolytes, and analyzed the reaction mechanism of CO2 reaction in the electrode-electrolyte interface region by experimental and simulation methods. Finally, the research which needs to be highlighted in this area was proposed.
文摘The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performance was investigated in a fixed-bed system with respect to the adsorption superficial velocity,ionic strength and pH.A mathematical model was used to simulate the mass transfer mechanism,taking film mass transfer,pore diffusion and axial dispersion into account.The model predictions were consistent with the experi-mental data and were consequently used to determine the mass transfer coefficients.
基金Project(2007BAE12B01)supported by the National Key Technology Research and Development Program of ChinaProject(20803095)supported by the National Natural Science Foundation of China
文摘To improve the low-temperature performances of Li-ion cells, three types of linear carboxylic ester-based electrolyte, such as EC/EMC/EA(1:1:2, mass ratio), EC/EMC/EP(1:1:2, mass ratio) and EC/EMC/EB(1:1:2, mass ratio), were prepared to substitute for industrial electrolyte(EC/EMC/DMC). Then, 18650-type Li Mn2O4-graphite cells(nominal capacity of 1150 mA ·h) were assembled and studied. Results show that the cells containing three types of electrolyte are able to undertake 5C discharging current with above 93% capacity retention at-20 °C. Electrochemical impedance spectra show that the discharge capacity fading of Li-ion cells at low temperature is mainly ascribed to the charge transfer resistance increasing with temperature decreasing. In comparison, the cells containing electrolyte of 1.0 mol/L LiPF6 in EC/EMC/EA(1:1:2, mass ratio) have the highest capacity retention of 90% at-40 °C and 44.41% at-60 °C, due to its lowest charge-transfer resistance.
基金Supported by the National Natural Science Foundation of China (20376015), the Natural Science Foundation of Guangdong Province (32491) and Guangzhou Project of Science & Technology (2004J1-C0151).
文摘Ionic liquids have been used as catalysts for Blanc reaction of toluene. The effects of reaction temperature, reaction time and dosage of the ionic liquid catalyst have been investigated, and the catalytic performance of different ionic liquid catalysts for toluene chloromethylation was also studied. The reaction was found to proceed under mild conditions with excellent conversion (up to 90%) in the absence of Lewis acids. The ionic liquids could be recycled and reused without loss of their catalytic activities.
基金the projects ENE2010-15585 and CTQ2012-31639the FPI postgraduate research grant(BES-2011-046279)
文摘Recovery of carbon monoxide from flue gases by selective absorption of carbon monoxide in an imidazolium chlorocuprate(l) ionic liquid is considered in this work as an alternative to the use of molecular volatile solvents such as aromatic hydrocarbons. The present work evaluates the CO mass transfer rates from the gas phase to the ionic liquid solutions in the absence of chemical reaction. To that end, carbon dioxide was employed as an inert model gas and absorption experiments were performed to assess the influence of different process variables in a batch reactor with fiat gas-liquid interface. The experimental mass transfer coefficients showed significant var- iation with temperature, (3.4-10.9) × 10^-7 m·s^-1 between 293 and 313 K; stirring speed, (10.2- 33.1)× 10^-7 m.s 1 between 100 and 300 r·min^-1; and concentration of copper(1), (6.6-10.2) × 10^-7 m·s^-1 between 0.25 and 2 mol· L^- 1. In addition, the mass transfer coefficients were eventually found to follow a poten- tial proportionality of the type kL ∝μ^-0.5 and the dimensionless correlation that makes the estimation of the mass transfer coefficients possible in the studied range of process variables was obtained: Sh=10^-2.64 Re^1.07 , Sc^0.75,These results constitute the first step in the kinetic analysis of the reaction between CO and imidazolium chlorocuprate(I) ionic liquid that determines the design of the separation units.