Toxicidade de solução aquosa de Pb (II) após tratamento por adsorção com nanopartículas de óxidos de ferro

Abstract

Contamination of water bodies has become an eminent problem, and treatments are being sought for pollutants that in order to de increase this contamination. In the present work, the use of the adsorption method with iron oxides, recovered from acid drainage of mines at Carbonifera de Criciúma, was used to treat an aqueous solution containing lead nitrate, and its efficiency monitored by mortality tests/ immobility with brine shrimp and escape with Eisenia fetida. The tests were carried out using samples of an aqueous solution of Pb (II) (100 mg of lead nitrate L-1 x distilled water) treated with goethite or hematite (50 g L-1) by the batch adsorption method, under pH 4 .0. After treatment, the mortality/immobility test with A. salina was performed with concentrations of 3.1; 6.2; 12.5; 25; 50 and 100% of the crude sample, treated with goethite or hematite, diluted in saline solution, for 24 hours. The escape test with E. fetida was carried out by exposing the worms to 48 hours of the treatment samples, in tropical artificial soil. For the two toxicity test tests, it was possible to observe the effectiveness, in terms of reduction or absence of toxicity, of the adsorption treatment for the goethite nano-oxide, making it important to carry out toxicity tests for effluents that have the presence of heavy metals.