Análise química de elementos potencialmente tóxicos em baterias e pilhas por FAAS e ICP OES

• Autor(a) principal: Santana, Ariane Maziero [UNESP]
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/124472; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/18-06-2015/000837283.pdf
• topic: Baterias; Microondas; Quimica analitica; Batteries

In this work analytical methods applied to batteries were developed. The first stage work consisted in the characterization of the active material of the samples and batteries. With Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) it was possible to calculate the mean particle size with a range from 8.08 to 22.96 μm and verifying the presence of toxic metals such as Cd, Cr and Ni. The Cd was found only in the nickel-cadmium - NiCd batteries only, the other potentially toxic elements (Cd, Cr, Pb, As and Hg) were not detected. For the characterization of active material and the samples with the aid of X- Ray Diffraction (XRD) it was possible to identify the presence of chemical compounds. Leaching test was conducted to promote the extraction of toxic metals present in the active material of batteries. The leachates were analyzed by Flame Atomic Absorption Spectrometry (FAAS) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) for the quantification of metals Cr, Cd, Ni and Pb. The procedure used to promote the extractions was the ABNT NBR 10.005/2004 devised for evaluating the toxicity of solid waste. The results obtained by the two techniques were concordant between themselves, with the application of the Student's t-test with 95% confidence level and were adequate for the determination of the analytes in the leachate extract. The NiCd battery showed a high concentration of Cd in its composition and was considered a toxic waste according to NBR 10.005/2004. For total determination of the analytes in the NiCd sample, a procedure for sample preparation was developed that resulted in complete digestion of the same in order to quantify the toxic metals by ICP OES. Procedure B was more suitable to promote digestion of the samples with the determination of Cr, Cd, Ni and Pb. The accuracy using procedure B was evaluated using the NiCd battery and the ...