Produção de carvão ativado a partir do endocarpo lenhoso de Syagrus Romanzoffiana (jerivá): aplicação no tratamento de efluente

Abstract

The search for precursor materials for the production of activated carbon that are low cost has been investigated, along with the application of the charcoal for the treatment of effluents. In this way, the objective of this work was to produce activated charcoal from the woody endocarp of Syagrus Romanzoffiana (jerivá) and to evaluate its potential use in the treatment of liquid effluents by adsorption. The precursor material was characterized for ash content and evaluated for thermogravimetry (TGA). The charcoal were prepared by the chemical activation method, using phosphoric acid (H3PO4) as the activating agent. The yield of the activated carbon produced was calculated and was characterized as TGA, DSC, zero load point (PCZ), ion exchange capacity, ash content, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (MEV). Charcoal were applied in effluent adsorption tests. It was found that the precursor material had 0.6514% ash content and the yield of the charcoal produced was 43.53%. TGA analysis indicated a loss of mass in three stages of the precursor material, associated with water loss (81,65 ºC), degradation of cellulose (256,04 ºC) and lignin (430,06 ºC) until carbonization of the charcoal. PCZ equal to pH 2.0 characterized charcoal as acid and with higher content of acid groups. The ion exchange capacity with the charcoal surface was 0.13 mol / kg and the charcoal ash content was 0.9505%. In the surface area analysis (BET) and porosity, the predominance of mesopores and a relatively large surface area of 1526.56 m² / g were observed. Through the SEM it was observed that activated charcoal has a rough and irregular surface. By means of the adsorption tests it was verified that activated charcoal was efficient in the treatment of the effluent, an analysis of variance (ANOVA) was done followed by the comparison test of Tukey averages (p <0.05) in which all evaluated parameters (DBO, DQO, color and turbidity) were significantly affected. The woody endocarp of jerivá presented potential to be used as precursor material of the activated charcoal, presenting potential to be used for adsorption of effluent.