Preparation And Properties Research Of Fe/Ni And Co/Ni Composite Nanomaterial By Emulsion Liquid Membrane Method

The emulsion liquid membrane method of internal phase precipitation has double advantages of extraction and reverse extraction in treating Iron Cobalt and Nickel transition metal wastewater.Iron Cobalt and Nickel can be selectively transferred from the external water phase to the internal phase by this technology,and these heavy metal ions are removed from the waste water with the form of precipitation.at the same time,composite-nano hydroxides and oxides of Iron Cobalt and Nickel have the good photocatalytic activity.This paper mainly studies the emulsion liquid membrane system with NaOH solution as the precipitant of internal phase for extraction and separation of Iron Cobalt and Nickel ion in the wastewater.The Fe/Ni composite-nano hydroxides,Fe/Ni composite-nano oxides and Co/Ni composite-nano oxides powders are prepared by this method in the experiment,respectively.The properties of these powders are also studied in the paper.This paper uses the internal phase precipitation to extract the Fe³⁺,Co²⁺ and Ni²⁺ from simulated wastewater by emulsion liquid membrane for the research.The emulsion liquid membrane of Span85-TBP-NaOH system is used to remove the Fe³⁺,Co²⁺ and Ni²⁺ in the experiment,The Fe/Ni composite-nano hydroxides powders are prepared by this method,Effects of the internal phase NaOH concentration,external Fe-Ni proportion,Span85 concentrations,agitation rate,dosage of samples and other factors on the photocatalytic activity of Fe/Ni composite-nano hydroxides samples are investigated with UV-Vis spectrophotometry,respectively.The phase,particle size,morphology and structure of samples are analyzed and researched with using FT-IR,XRD,SEM,and other detection means in the experiment.The results show that the higher photocatalytic activity of Fe/Ni composite-nano hydroxides sample is obtained at internal phase NaOH concentration of 0.35 mol/L,external Fe-Ni proportion of 1:3,Span85 concentrations of 5%,agitation rate of 300 r/min,dosage of samples of 0.1g,and its photocatalytic activity is up to 88% for 4 mg/L methylene blue solution.The obtained powder samples are nanometer ?-Ni?OH?₂,?-Ni?OH?₂ and Fe O?OH?,and the particle size of Ni?OH?₂ is between 5.1 nm and 10.9 nm,the particle size of Fe O?OH?is between 6 nm and 8.7 nm,and the sample have apparent reunion phenomenon among the particles.The Fe/Ni composite-nano hydroxides powders prepared by emulsion liquid membrane are calcinated under certain temperature in this experiment.Effects of the internal phase NaOH concentration,external Fe-Ni proportion,Span85 concentrations,agitation rate,calcination temperature and other factors on the photocatalytic activity of Fe/Ni composite-nano oxides samples are investigated with UV-Vis spectrophotometry,respectively.The surface morphology and physical and chemical properties of samples are analyzed and researched with using FT-IR,XRD,SEM,and other detection means in the experiment.The results show that the higher photocatalytic activity of Fe/Ni composite-nano oxides sample is obtained at internal phase NaOH concentration of 0.40 mol/L,n(Fe³⁺):n(Ni²⁺)=1:3,Span85 concentrations of 3%,agitation rate of 300 r/min,calcination temperature of 400?,and its photocatalytic activity is up to 97% for 4 mg/L methylene blue solution.The obtained powder samples are nanometer Fe2O3 and NiO,the particle size of NiO is between 9 nm and 19 nm,the particle size of Fe2O3 is between 11 nm and 25 nm,and the sample have apparent reunion phenomenon among the particles.Co/Ni composite-nano hydroxides samples are prepared in the same way,Effects of the internal phase NaOH concentration,external Fe-Ni proportion,Span85 concentrations,agitation rate,calcination temperature and other factors on the photocatalytic activity of Co/Ni composite-nano oxides samples are investigated with UV-Vis spectrophotometry,respectively.The surface morphology and physical and chemical properties of samples are analyzed and researched with different detection means in the experiment.The results show that the higher photocatalytic activity of sample is obtained at internal phase NaOH concentration of 0.30 mol/L,n(Co²⁺):n(Ni²⁺)=1:3,Span85 concentrations of 5 %,agitation rate of 300 r/min,calcination temperature of 350 ?,and its photocatalytic activity is up to 98% for 4 mg/L methylene blue solution.The obtained powder samples are nanometer NiO and Co₃O₄,they have also obvious reunion phenomenon among the particles.The particle size of NiO is between 12.4 nm and 18.3 nm,the particle size of Co₃O₄ is between 13 nm and 32 nm.