The invention discloses a method and device for synchronously purifying and concentrating a ferric trichloride solution. By means of the characteristics that FeCl3 is a covalent compound and is easily polymerized into high-molecular-weight poly ferric trichloride in a water solution, the ferric trichloride solution is sprayed into fog, and as fog particles carrying poly ferric trichloride are heavy, the lift and the range of the fog particles are smallest; the lift and the range of pure H2O fog particles (water vapor) are largest; as the content of the fog particles carrying other chemical components (such as copper chloride, calcium chloride, zinc chloride and cadmium chloride) is small, the lift and the range of the fog particles are between those of the fog particles carrying poly ferric trichloride and those of the pure H2O fog particles, atomizing particles with different lifts are collected at different positions by means of the characteristic, and therefore the purpose of purifying and concentrating ferric trichloride and other solutions is achieved. According to the method, the problems that in a traditional process method, a large amount of energy is consumed, due to FeCl3 volatilization, pipeline blockage and absorption tower blockage are caused, and the content of impurities of FeCl3 solution products is high are solved.