Waste pickling liquors （WPLs） containing high concentrations of iron and acid are hazardous waste products from the steel pickling processes. A novel combined coprecipitation-oxidation method for iron recovery by Fe...Waste pickling liquors （WPLs） containing high concentrations of iron and acid are hazardous waste products from the steel pickling processes. A novel combined coprecipitation-oxidation method for iron recovery by Fe304 nanoparhcle＇ production from the WPLs was developed in this study. 2＋All oxidation-reduction potential monitoring method was developed for real-time control of the Fe2＋/Fe3＋ molar ratio. The key coprecipitation-oxidation parameters were determined using the orthogonal experimental design method. The use of promoters greatly improved the Fe3O4 nanoparticle crystallinity, size, magnetization, and dispersion. X-ray diffraction patterns showed that the produced Fe3O4. nanoparticles were single phase. The Fe3O4 nan oparticles were approximately spherical and slightly aggtomerated. Vibrating sample magnetometry showed that the Fe3O4 nanopahicles produced from the WPLs had good magnetic properties, with a saturation magnetization of 80.206 emu. g-1 and a remanence of 10.500 emu. g-1. The results show that this novel coprecipitation-oxidation method has great potential for recycling iron in WPLs.展开更多
文摘Waste pickling liquors （WPLs） containing high concentrations of iron and acid are hazardous waste products from the steel pickling processes. A novel combined coprecipitation-oxidation method for iron recovery by Fe304 nanoparhcle＇ production from the WPLs was developed in this study. 2＋All oxidation-reduction potential monitoring method was developed for real-time control of the Fe2＋/Fe3＋ molar ratio. The key coprecipitation-oxidation parameters were determined using the orthogonal experimental design method. The use of promoters greatly improved the Fe3O4 nanoparticle crystallinity, size, magnetization, and dispersion. X-ray diffraction patterns showed that the produced Fe3O4. nanoparticles were single phase. The Fe3O4 nan oparticles were approximately spherical and slightly aggtomerated. Vibrating sample magnetometry showed that the Fe3O4 nanopahicles produced from the WPLs had good magnetic properties, with a saturation magnetization of 80.206 emu. g-1 and a remanence of 10.500 emu. g-1. The results show that this novel coprecipitation-oxidation method has great potential for recycling iron in WPLs.
