The Technology On The Iron And Nickel Were Drawn From Sodium Jarosite's Slag And Preparation Of The High Frequency Ni-Zn Ferrite

There are develop way on preparaeing functional material by full utilize non-ferrous metal in industrial slag with new method and technology. Ni-Zn ferrites were synthesized by hydrothermal synthesis method using sodium jarosite's slag as materials, the process of reduction-roast and leaching of sodium jarosite's slag, the leaching solution purified, the characteristic and apply of Fe₂O₃ powders prepared by precipitation method, the thermodynamics, kinetics, microstructure and reaction process of hydrothermal system were discussed, the parameters having effects on sintered mechanism of densification, microstructure and magnetic properties were investigated, the fitful technical conditions were obtained.The iron and nickel were drawn using the method of reduction-roast and leaching from sodium jarosite's slag with anthracite. Sodium jarosite—anthracite ratio is 5:1, reduction roasting lasts for 30min at 800℃, leaching is carried out for 40min at 70℃by 0.7mol/L H₂SO₄ while liquid-solid ratio 5:1, 90% of iron and 83% nickel can be leached out. The reaction activation energy of leaching is 48.7kJ·mol^-1, the process of leaching were control of chemistry reaction.The results of analysis on thermodynamics shown that the Ca²⁺ and Mg²⁺ et al would be removed from the leaching liquid using NaF. The uniform and shperoidalα-Fe₂O₃ nanoparticles with high purity are obtained by precipitation method using FeSO₄ purified. The characteristic and apply of Fe₂O₃ powders shown that they can be used in the intermediate grade and the high grade NiZn ferrite inductors.The Ni-Zn ferrite powders were prepared by hydrothermal method using purified leaching solution. The decompose trend of metal salt solution were calculated on thermodynamics in hydrothermal system. The phase, morphology, grain size and construction properties were determined with the aid of TEM, XRD, IR and ICE The kinetics of hydrothermal system was discussed. The results of experiment shown that the nanoparticles powder are spinel ferrite and satisfied with require of stoicheiometric compound, the crystal lattice constant is seen to increase linearly and the ferrite stretching position is shifted to lower wave number with Zn content increase. It is clearly shown that XRD densities decrease with increasing of Zn content increase. Steady energy of crystalline field shown that the trend of metal cation enter into the space cavity on spinel ferriteThe hydrothermal method ferrite powders were to cores and sintered, the phase, morphology, density and linear shrinkage were analyzed, the sintering temperature, time of the heat preservation and additives on the sintering characteristic were studied. Grains size increase, crystal construction more complete and densification degree increase with sintering temperature increase or time of the heat preservation. The densification degree increased with lower sintering temperature when additive of CuO. At sintering earlier stage, grains growth were control with pore migrate process by interface reaction or crystal boundary diffusion. The grains rapid growths which were controls with crystal boundary migrate by crystal boundary diffusion, there growth degree were more rapid than densification degree at sintering later stage. According to Huang Peiyun's Synthesize Sintering Theory, the main matter migrate mechanism of ferrite sintering should be grain boundary diffusion, and there also exists volume diffusion. The sintering equation was:The kinetics equation of shrinkags were:1100℃: ln(â–³L/L₀)=(1/2.89)1nt—0.941200℃: ln(â–³L/L₀)=(1/2.91)lnt—0.571300℃: In(â–³L/L₀)=(1/2.87)lnt—0.381350℃: ln(â–³L/L₀)=(1/2.94)lnt—0.29The magnetic properties of cores wrapped wires were measured on TYU-2000 magnetic automatic measure equipment et al. The effects of sintering temperature, time of the heat preservation and additives on sintered Ni-Zn ferrite were investigated. Comparison between hydrothermal ferrite using sodium jarosite's slag as materials and commercial ferrite showed that the magnetic properties of hydrothermal ferrite were not inferior to the latter.According to composition's properties of sodium jarosite's slag, the Fe₂O₃ powders prepared by precipitation method can be used in the intermediate grade and the high grade NiZn ferrite inductors, the Ni-Zn ferrite were prepared by hydrothermal synthesis method with high productivity and low consumption, and the manufacture satisfied with the magnetic properties of commercial ferrite. It is beneficial to scale industrial appliance for sodium jarosite's slag, and this can be used as a good reference to the industrial slag.