Caracterização Físico-química dos resíduos líquidos gerados no laboratório de eletroquímica e corrosão do CES- UFCG.

Abstract

Research laboratories generate very significant amounts of effluents liquids with a high toxic load, consisting of heavy and complexing metals that when disposed of or improperly disposed of, they cause serious damage to the environment environment and human health. When choosing a method of treatment or disposal final and essential to know in detail the characteristics of the waste, its origin, and its constituents. As this knowledge is often not viable, indispensable preliminary tests of the process efficiency and feasibility studies technical-economic For this purpose, this work presents a whole investigation and a survey, regarding the quantity, variety, form of storage, identification of liabilities and form of disposal of these liquid residues generated in the Electrochemistry laboratory of UFCG- CES, Cuité campus. Soon the work was divided into three parts, where first there was a survey of the liabilities stored in the laboratory. On Monday stage, the identification and separation of the residues was carried out, by color, an analysis visual, making a superficial separation and storage. In the third, the characterization of the residue. In the fourth and last stage, precipitation tests were performed with Na OH and Na2HP04, as a proposal for a possible and subsequent treatment of these waste. We concluded that visual analysis allowed us to separate by colors, and made us deduct the main component of each container / color. The determination of ST by evaporation, proved to be efficient in reducing the liquid fraction, waste. The pH of liquid waste and similar to the pH values ​​used in the electrodeposition processes of the LEC, being in a range of 6.4 to 7.4. The density of the residues is proportional to the used in research electrodeposits. Of the precipitation analyzes, the highest percentage of metal removal was with the addition of 10.0mL of Na2HP04 to 20mL of liquid residue, which presented the lowest conductivity and pH. Therefore, we conclude that the precipitation process, in the treatment primary residue, proved to be efficient and satisfactory.