The current study presents for the first time the preparation of a NiAl(68%(mass)Ni)intermetallic compound through the induction heating technique as a cathode for alkaline water electrolysis.The high-purity target wa...The current study presents for the first time the preparation of a NiAl(68%(mass)Ni)intermetallic compound through the induction heating technique as a cathode for alkaline water electrolysis.The high-purity target was confirmed by X-ray diffraction and scanning electron microscopy combined with energy dispersive X-ray analysis.The chemical activation of Al from the NiAl electrode was achieved in a 25%NaOH solution at 353 K for 72 h.The performance and stability tests in a 1 mol·L^(-1)KOH solution at 298 K demonstrated that the enhancement of the hydrogen evolution reactionwas 13 times higher in the activated NiAl electrode than in the non-activated NiAl electrode.In addition,the electrochemical tests showed that the activated NiAl electrode exhibited the best hydrogen evolution reaction performance.Based on the findings,it is believed that the induction heating technique is a promising route for preparing a highly active and cost-effective NiAl electrode for green hydrogen production.展开更多
The present research work examines extraction mechanism of zinc by D2 EHPA(Di-2-ethyl hexyl phosphoric acid) and comprehensively studies the main effective parameters on the process. Results of thermodynamic experimen...The present research work examines extraction mechanism of zinc by D2 EHPA(Di-2-ethyl hexyl phosphoric acid) and comprehensively studies the main effective parameters on the process. Results of thermodynamic experiments showed that zinc extraction by D2 EHPA was endothermic and spontaneous, and thermodynamic parameters including entropy and enthalpy were + 27.37 J·mol^(-1)·K^(-1) and 25.21 kJ·mol^(-1), respectively.Gibbs free energy was varied between-7.21 kJ·mol^(-1) and-8.41 kJ·mol^(-1) with the variation of temperature from 20 °C to 70 °C. Solution ionic strength was increased by addition of potassium and lithium sulfate solution while addition of calcium sulfate decreased ionic strength whereby zinc extraction efficiency was also decreased.TBP showed positive synergism at concentration of 5%(v/v) and negative synergism effect at concentrations of2% and 10%. Simultaneous addition of both TBP and salt caused extraction efficiency to drop significantly and lower both TBP and ionic strength efficiency. Results showed that a continuous addition of TBP tends to effectively improve the zinc extraction efficiency. Experiments in the presence of catalyst Ni-Raney demonstrated that zinc extraction kinetic increases remarkably and due to easy recycling of the catalyst, we can propose a novel idea in solvent extraction field.展开更多
文摘The current study presents for the first time the preparation of a NiAl(68%(mass)Ni)intermetallic compound through the induction heating technique as a cathode for alkaline water electrolysis.The high-purity target was confirmed by X-ray diffraction and scanning electron microscopy combined with energy dispersive X-ray analysis.The chemical activation of Al from the NiAl electrode was achieved in a 25%NaOH solution at 353 K for 72 h.The performance and stability tests in a 1 mol·L^(-1)KOH solution at 298 K demonstrated that the enhancement of the hydrogen evolution reactionwas 13 times higher in the activated NiAl electrode than in the non-activated NiAl electrode.In addition,the electrochemical tests showed that the activated NiAl electrode exhibited the best hydrogen evolution reaction performance.Based on the findings,it is believed that the induction heating technique is a promising route for preparing a highly active and cost-effective NiAl electrode for green hydrogen production.
文摘The present research work examines extraction mechanism of zinc by D2 EHPA(Di-2-ethyl hexyl phosphoric acid) and comprehensively studies the main effective parameters on the process. Results of thermodynamic experiments showed that zinc extraction by D2 EHPA was endothermic and spontaneous, and thermodynamic parameters including entropy and enthalpy were + 27.37 J·mol^(-1)·K^(-1) and 25.21 kJ·mol^(-1), respectively.Gibbs free energy was varied between-7.21 kJ·mol^(-1) and-8.41 kJ·mol^(-1) with the variation of temperature from 20 °C to 70 °C. Solution ionic strength was increased by addition of potassium and lithium sulfate solution while addition of calcium sulfate decreased ionic strength whereby zinc extraction efficiency was also decreased.TBP showed positive synergism at concentration of 5%(v/v) and negative synergism effect at concentrations of2% and 10%. Simultaneous addition of both TBP and salt caused extraction efficiency to drop significantly and lower both TBP and ionic strength efficiency. Results showed that a continuous addition of TBP tends to effectively improve the zinc extraction efficiency. Experiments in the presence of catalyst Ni-Raney demonstrated that zinc extraction kinetic increases remarkably and due to easy recycling of the catalyst, we can propose a novel idea in solvent extraction field.
