RECONHECIMENTO E CLASSIFICAÇÃO DE METAIS PESADOS EM ÁGUA ATRAVÉS DA MUDANÇA DE COR DA MOLÉCULA DIFENILTIOCARBOZONA

The present work reports a methodology of classification and recognition of metal ions of cadmium, chromium, mercury and zinc respectively. For this purpose we used a solution of Diphenylthiocarbazona in methanol as a sensitive system leveraging the photochrome property of this molecule when complexed with metal ions. The proposed classification method using principal component analysis of Fourier coefficients corresponding to the absorption curves fitting proved to be efficient. The read of the color shift of Diphenylthiocarbozona in methanol solution, after the addition of different concentrations of metal ions, was obtained with the RGB sensor integrated into a mobile system smartphone, the results of RGB levels reading by this process showed the possibility of using this system for in situ analysis of the concentration of metal ions in rivers. Index Terms - Heavy metal determination, Colorimetry, Optical sensors, Image processing, Mobile devices.