Qu Jingkui

Electrodeposition of Aluminum from AlCl3/Et3NHCl Ionic Liquids

Aluminum was successfully electrodeposited on Al electrodes from aluminum chloride (AlCl3)/triethylamine hydrochloride (Et3NHCl) ionic liquids by the constant potential electrolysis. Electrical conductivities of AlCl3/Et3NHCl ionic liquids were measured as a function of the temperature and composition. The nucleation processes and the influence of experimental conditions on the current efficiency and surface morphology of aluminum electrodeposits were studied on Al electrodes from 2:1 molar ratio AlCl3/Et3NHCl ionic liquid. The electrical conductivities of ionic liquids increased as the electrolyte temperature increased, following the Arrhenius behavior. Analyses of the chronoamperograms indicated that the deposition process of aluminium on Al substrates was controlled by instantaneous nucleation with diffusion-controlled growth. Constant potential deposition experiments showed that the electrodeposits obtained on Al electrodes were dense, continuous, and well adherent, and the current efficiency was 73% at -2.4 V (vs Pt) for 20 min electrolysis at room temperature. The purity of aluminum electrodeposits on Al electrodes was above 96% (w).

Equilibrium Solubility Modeling of CO 2 in Na 2 Cr 2 O 7 Solutions

The solubility of CO2 in aqueous Na2Cr2O7 solutions of different concentrations (0, 0.361, 0.650, and 0.901 mol.kg(-1)) was measured in a stirred vapor-liquid high-pressure equilibrium cell using the static method at temperatures and pressures in the ranges of 313.2 to 333.2 K and 0.1 to 1.9 MPa, respectively. The results indicated that the phenomenon of CO2 dissolved in aqueous Na2Cr2O7 could be interpreted according to a salting-out effect. Furthermore, our solubility data for CO2 in aqueous Na2Cr2O7 was in agreement with Henrys law, and the Henry constant appeared to be a function of temperature, pressure, and the concentration of Na2Cr2O2. Two thermodynamic models were applied to correlate the experimental data, including the modified Setschenow and Peng-Robinson-Pitzer equations, and the averaged relative deviations were found to be 4.24% and 3.32%, respectively.

Equilibrium Solubility Modeling of CO2 in Na2Cr2O7 Solutions

The solubility of CO2 in aqueous Na2Cr2O7 solutions of different concentrations (0, 0.361, 0.650, and 0.901 mol.kg(-1)) was measured in a stirred vapor-liquid high-pressure equilibrium cell using the static method at temperatures and pressures in the ranges of 313.2 to 333.2 K and 0.1 to 1.9 MPa, respectively. The results indicated that the phenomenon of CO2 dissolved in aqueous Na2Cr2O7 could be interpreted according to a salting-out effect. Furthermore, our solubility data for CO2 in aqueous Na2Cr2O7 was in agreement with Henrys law, and the Henry constant appeared to be a function of temperature, pressure, and the concentration of Na2Cr2O2. Two thermodynamic models were applied to correlate the experimental data, including the modified Setschenow and Peng-Robinson-Pitzer equations, and the averaged relative deviations were found to be 4.24% and 3.32%, respectively.