Concentration of trace components using freezing and meltingprocess of eutectics of salt and water-Magnetic field effect-

摘要

Alkali halide aqueous solution forms eutectics of salt and water at low temperature.Bykeeping the temperature at which only the eutectics of salt and water melted at around 0 to－20 °C,trace elements in water can be concentrated to the eutectic mixture.In the temperaturerange above the eutectic point and below the melting point of ice,only the eutectic mixtureexists as a liquid phase,so it was thought that a new low-temperature separation andconcentration method could be constructed.Since the eutectic point depends on the alkalihalide,the applicable temperature range is different.Previous studies have shown that when anexternal magnetic field is applied to the stationary phase during eutectic formation,the meltingenthalpy of the eutectics decreases and the amount of trace components such as Co decreasesin the stationary phase.In this study,a new experimental system was developed to improve theaccuracy of temperature control,and the effects of external magnetic fields during separationwere also investigated.