Estudo da remediação de água contaminada com corantes por adsorção em compósitos de amido termoplástico (TPS) e lignina kraft

Abstract

The disposal of industrial effluents containing dyes creates a major environmental problem, both for aquatic life and for public health. In order to remove these dyes from effluents, adsorption is an easy and extremely viable technique, especially when it involves the use of bioadsorbents. A potential bioadsorbent for the removal of dyes are TPS starch compounds and kraft starch-lignin, since they can be obtained from renewable and low-cost raw materials. The objective of this work was the use of pure starch films (TPS) and the kraft starch-lignin compound (TPS-KL) for the adsorption of two dyes: methylene blue and methyl orange. The study was carried out through the results of adsorption and desorption for these two films obtained by UV-vis spectroscopy. Subsequently, the films were characterized by their morphological (Scanning Electron Microscopy), chemical (infrared Fourier transform and visible ultraviolet spectroscopy) and physicochemical (solubility and thickness) characteristics, before and after undergoing dye adsorption. The results obtained experimentally show that the TPS-KL starch biosorbent presented a high removal potential (~95%) for the methylene blue dye, with a maximum adsorption capacity of 175,92 mg g-1, but a low potential for removal (~22%) for the methyl orange dye, with a maximum adsorption capacity of 40,74 mg g-1, proving its efficiency for use in effluent treatments. Therefore, it is a viable process and less aggressive to the environment, since it uses lignin and starch, biomass components, as adsorbent.