Determination of pb concentration level in cathode ray tubes by atomic absorption spectrometry

Objectives: In the present work were employed methods for the determination of lead glass from cathode ray tubes. For the analysis, they used small pieces of CRT components (television and computer) from different manufacturers and dismantled by hand. After milling, vitreous samples were analysed by SEM, EDS and XRD to determine the particle size and the elemental composition of the investigated material. For this study was used a mixture ratio of 1: 1: 1: 4 by weight (electron gun neck, funnel and screen). For the analyzes by GFAAS samples were digested in acid medium (HCl 2.4 ml, 1.2 ml HNO3, 2.4 mL HF and 2.0 mL H2O), where about 125mg of the glass sample. They were added PTFE bottle. The total concentration of lead in CRTs and GFAAS was determined by the values found for two mixtures from different samples were (735.52 ± 6.12) mg kg -1 and (886.61 ± 5.49) mg kg -1 . The toxicity of the sample was evaluated using the standard NBR 10004: 2004 for solid waste. The mixture was subjected to leaching tests and the leaching extract was analysed by atomic absorption spectrometry flame (FAAS) and optical emission spectrometry with inductively coupled plasma (ICP OES). The results indicated that about 85% of Pb present in the leach residue. The leaching tests for CRTs waste reached the Class I values (hazardous waste) according to the ABNT NBR 10004: 2004, due to the high concentration of lead present in its composition.