Avaliação das fases sólidas poli(vinil-piridina) e aerogel de grafeno na pré-concentração de clorofenóis e íons cádmio em amostras ambientais

Abstract

The inadequate use of water resources, the unregulated application of chemicals, the inconsequential contamination and pollution of aquatic environments, food, flora and fauna associated with the lack of information regarding the actual toxicity of these compounds and Its processing products, tends to aggravate the risks to public health and the environment. This is because in certain forms, these organic or inorganic contaminants can represent high toxicity even at low concentrations. For example, chlorophenic compounds due to their persistence in the environment and important toxicological effects are targets of the first part of this study, where the results of the investigation of Poly polymer (4-vinylpyridine) and its adsorptive capacity of phenolic species, followed by High Performance Liquid Chromatography analysis with column switching coupling. For 2.4 dichlorophenol: LD of 0.9953 μg L-1, LQ of 3.0161 μg L-1 and linear analytical curve from 0.3 to 3.0 μg L-1 (r = 0.9879), Preconcentration factor of 75, and consumption index of 0.040 mL were achieved. For 2, 4, 6-trichloroophenol: LD of 0.1849 μg L-1, LQ of 0.5605 μg L-1, linear analytical curve from 0.3 to 3.0 μg.L-1 (r = 0.9951), Preconcentration factor of 85, consumption index of 0.035 mL. The samples collected in the Sapucaí arm and the Clube Náutico region in the Furnas Dam-MG, however, the study analytes were not detected. The evaluation of inorganic species focused on cadmium, which with its bioaccumulative power and carcinogenic effect has great relevance, so the second part of the work describes the performance of three-dimensional graphene aerogels (GA-3D) as an extractive phase of cadmium ions with detection by flame atomic absorption spectrometry. The experimental parameters were studied using multivariate optimization techniques such as factorial design and Doehlert matrix. The analytical characteristics found were: linear response from 5.0 to 300.0 μg L-1 (r = 0.9968), limit of detection and quantification, 1.67 and 5.58 μg L- 1, respectively, pre-concentration factor of 20, consumption index 1.18 mL, and analytical Frequency 20 h-1. The interference of concurrent ions was investigated and the accuracy was verified by means of addition and recovery tests. The samples were analyzed water from the reservoir point 1 (54 ± 0.08 μg L-1); Point 2 (108 ± 1.52 μg L-1) and mine water (57 ± 4.30 μg L-1).