[en] The laser-induced chemical reaction process is a high-tech process which can be applied to the extraction of the precious elements from the polluted solutions, elimination of the radioisotopes with long half life. the recycling of the industrial water in various industries. In this project the optimum reaction process was established by using the 2nd harmonic as well as 3rd harmonic of the Nd:YAG laser. Once an optimal experimental condition is achieved with the use of TiO₂ as a catalyst and acidic solvent, the chromium was precipitated efficiently as the reaction proceeds. Europium was selected as a representing element for the lanthanide elements and the optimum reaction process was identified. For this sample balance state of +3 was transformed to +2 by the photo reaction. In order to apply the reaction process which was developed in the present study, polluted water collected from the garbage disposal site was tested. As a result heavy metal elements were efficiently extracted due to the photo-reaction. (author)